Lunar and Planetary Institute






21st Lunar and Planetary Science Conference

TABLE OF CONTENTS

no.

Limits on the Compositional Variability of the Martian Surface
J. B. Adams, M. O. Smith
  1001

Aqueous Processing of Lunar Regolith for In-Situ Production of Structural Materials and Fuels
W. N. Agosto
  1002

Development of a Solid-state Mossbauer Spectrometer for Planetary Missions
D. G. Agresti, E. L. Wills, T. D. Shelfer, J. S. Iwanczyk, N. Dorri, R. V. Morris
  1003

Contribution to the Study of Thermal Erosion on Mars
J. Aguirre-Puente, F. M. Costard, R. Posado-Cano
  1004

Ion Probe Studies of Interstellar SiC in Ordinary Chondrites
C. M. O'd. Alexander, J. W. Arden, J. Pier, R. M. Walker, C. T. Pillinger
  1005

The Detection of SiC In Situ in CM Meteorites: A Progress Report
C. M. O'd. Alexander, P. D. Swan, R. M. Walker
  1006

Venera 15 and 16 Spacecraft: Some Results of Venus Surface Reflectivity Measurements
Yu. N. Alexandrov, A. P. Krivtsov, O. N. Rzhiga
  1007

Venera 15, 16 Spacecraft: an Efficiency of Joint Employment of SAR and Radar Altimeter for Exploration of Venus Surface
Yu. N. Alexandrov, I. L. Kucheryavenkova, G. M. Petrov, O. N. Rzhiga, A. I. Sidorenko
  1008

Chemical Weathering of Basaltic Rocks Under Cold Arid Conditions
C. C. Allen, J. L. Conca
  1009

Interstellar Graphite in Meteorites: Growing Complexity, Implied by its Noble-Gas Components
S. Amari, R. S. Lewis, E. Anders
  1010

Thermal State of Venus Inferred from Its Gravity and Surface Topography
J. Arkani-Hamed
  1011

Petrography and Trace Element Chemistry of Colomera (IIE) Silicate Inclusions: Rhyolitic Plums in the Pudding
J. T. Armstrong, A. K. Kennedy, P. K. Carpenter, A. L. Albee
  1012

Overview of the Geoscience Discipline Node of the Planetary Data System
R. E. Arvidson
  1013

Geologic Remote Sensing Field Experiment
R. E. Arvidson, D. L. Evans
  1014

Two-Dimensional Fragmentation Hydrocode
E. Asphaug, E. Ryan, H. J. Melosh
  1015

Arecibo-Venera Comparison of Domes in Guinevere Planitia, Venus
J. C. Aubele
  1016

Two Global Concentrations of Small Dome-like Hills on Venus
J. C. Aubele
  1017

Multi Kubelka Analysis of VIS-NIR Reflectance Spectra
H. Azuma, N. Fujii
  1018

Shock Metamorphic Effects Caused by Hypervelocity Impact of Meteorite Projectile into Quartz Target
D. D. Badjukov
  1019

Microdistribution and Correlation of Trace Elements in Mineral Grains of Semarkona (LL3.0) and Dhajala (H3.8) as Determined by PIXE Analysis
S. Bajt, E. Pernicka, K. Traxel
  1020

Ancient Ocean-Land-Atmosphere Interactions on Mars: Global Model and Geological Evidence
V. R. Baker, R. G. Strom, S. K. Croft, V. C. Gulick, J. S. Kargel, G. Komatsu
  1021

The Evolution of Tharsis: Implications of Gravity, Topography, and Tectonics
W. B. Banerdt, M. P. Golombek
  1022

Martian Impact Craters: Continuing Analysis of Lobate Ejecta Sinuosity
N. G. Barlow
  1023

High Pressure Experiments on Magnesian Eucrite Magmas: Constraints on Magmatic Processes in the Eucrite Parent Body
K. S. Bartels, T. L. Grove
  1024

The Vital Problems of Venus Geology and Outlooks of Their Resolving by Magellan and Post-Magellan Missions
A. T. Basilevsky
  1025

Pre-Magellan Mapping of Northern Venus: Completion of a Joint U.S./U.S.S.R. Project
A. T. Basilevsky, R. M. Batson, G. A. Burba
  1026

Soils in 15009 and the Geology of the Apollo 15 Site
A. Basu, S. J. Wentworth, D. S. McKay
  1027

The Metamorphic, Shock and Brecciation History of Eucrite Association Meteorites
J. D. Batchelor, D. W. G. Sears
  1028

Model Calculations of Solar Wind and SEP Neon Isotopic Distributions in Lunar Regolith Grains
R. H. Becker
  1029

Color Units on the Uranian Satellites: an Outer Solar System Analog to Lunar Vitrification Darkening?
J. F. Bell III
  1030

Can Iron Oxide/Oxyhydroxide Minerals be Identified on the Martian Surface from Groundbased VIS-NIR Spectra?
J. F. Bell III, T. B. McCord
  1031

Groundbased Imaging Spectroscopy of Mars During 1988 and 1990: Instrumentation and Methodologies for the Future of Planetary Spectroscopy
J. F. Bell III, P. G. Lucey, T. B. McCord, T. Ozoroski
  1032

Comparison of New Groundbased and Phobos-2 VSK Color Ratio Data for Mars
J. F. Bell III, M. S. Robinson, T. B. McCord, F. P. Fanale
  1033

Irradiation Effects on the Surface of Icy Bodies
J. Benit, J.-P. Bibring
  1034

Iron-enriched Smectite Clays as Mars Soil Analogs: Chemical Reactivity in the Labeled Release Experiment
T. Ben-Shlomo, A. Banin
  1035

Petrology of Newly Recovered Orthopyroxene-Bearing Antarctic Ureilites: A New Ureilite Type?
J. L. Berkley
  1036

Strange Clasts in Antarctic Howardites: Evidence for Advanced Differentiation and Complex Processes
J. L. Berkley
  1037

Martian Mantle Primary Melts
C. M. Bertka, J. R. Holloway
  1038

Digital Mosaic and Elevation Model of Central Valles Marineris, Mars
L. M. Bertolini, A. S. McEwen
  1039

Preliminary Quantitative Assessment and Analysis of PHOBOS 88 Termoskan Observations of Mars
B. H. Betts, T. Svitek, M. L. Santee, B. C. Murray, D. Crisp, D. A. Paige, M. Naraeva, A. Selivanov
  1040

The Observation of the Surface of Mars by the ISM Instrument on Board the PHOBOS 2 Spacecraft
J. P. Bibring, Y. Langevin, S. Erard, O. Forni, P. Masson, C. Sotin, M. Combes, V. Moroz, A. Coradini, V. Formisano, J. Head, L. Soderblom, F. Fanale, T. McCord, D. Cruikshank
  1041

Obliquity Histories of Earth and Mars: Influence of Inertial and Dissipative Core-Mantle Coupling
B. G. Bills
  1042

Origin and Evolution of the Tessera Terrain of Venus: Implications for Global Tectonics and Magellan
D. L. Bindschadler
  1043

Troughts Around Venusian Volcanoes: Implications for Properties of the Lithosphere
D. L. Bindschadler, E. R. Stofan
  1044

Long Term Variations of a Volatile Methane Reservoir on Pluto
R. P. Binzel
  1045

Proto-Jupiter Perturbations in the Primordial Asteroid Belt
C. Biral, M. Fabris, F. Marzari, V. Vanzani
  1046

Terrestrial Analog Studies of Early Martian Environments: Chemical Analysis of Sediments from Lake Hoare, Antarctica
J. L. Bishop, R. A. Wharton, C. Koeberl, C. P. McKay, L. A. Foster, P. A. J. Englert
  1047

Orbital Stability: Constraints on the Nature of Other Planetary Systems
D. C. Black, A. Eck, A. A. Jackson
  1048

Direct Determination of the Morphology, Structure and Composition of Planetary, Cometary and Interstellar Ice Analogs
D. F. Blake, L. J. Allamandola, G. Palmer
  1049

Implications of the Low Carbonate Abundance in the Optical Surface of Mars
D. L. Blaney
  1050

Earth-based Telescopic Observations of Mars in the 4.4 micron to 5.1 micron Region
D. L. Blaney, T. B. McCord
  1051

Processing of Mars Surface Images Received from Phobos-2 Space Station
I. M. Bockstein, P. A. Chochia, M. A. Kronrod, Yu. M. Gektin
  1052

The Chico, NM, L-6 Chondrite: A Large, 500 My-Old Impact Melt with a Long Cosmic Ray Exposure
D. D. Bogard, D. H. Garrison, E. R. D. Scott, K. Keil, G. J. Taylor, S. Vogt, G. F. Herzog, J. Klein
  1053

A Major-2.1 GA Impact Event Recorded in Some Apollo 15 KREEP Basalts Autolycus?
D. D. Bogard, G. Ryder, D. H. Garrison
  1054

K-T Spherules--Clarifying the Concept
B. F. Bohor, W. J. Betterton
  1055

REE Abundances of Tonsteins and K-T Boundary Claystones by ICP-MS
B. F. Bohor, A. L. Meier
  1056

Entry Corridor of Micrometeorites Containing Organic Material
P. Bonny, D. Balageas
  1057

Ammonia-Water Mixtures High Pressures Revisited
S. Boone, M. F. Nicol
  1058

Natural Detonations in the Earth and Theoretical Limits on Associated Shock Pressures
M. B. Boslough
  1059

Tidal Disruption of Inviscid Protoplanets
A. P. Boss, A. G. W. Cameron, W. Benz
  1060

Mapping Effects of Distant Peturbations on Particle-Planet Encounters
W. F. Bottke Jr., R. Greenberg, G. B. Valsecchi, A. Carusi
  1061

The Canteloupe Terrain of Triton
J. M. Boyce
  1062

Constraints on the Shock and Thermal Histories of some Components from the Unique Chondrite, Allan Hills 85085, and Their Implications
A. J. Brearley
  1063

Matrix Mineralogy of the Unequilibrated CO3 Chondrite, ALH A77307: Evidence for Disequilibrium Condensation Processes and Implications for the Origin of Chondrite Matrices
A. J. Brearley
  1064

The Spectral Effects of Dispersed Opaques in Optically Altered Ordinary Chondrites
D. T. Britt, C. M. Pieters
  1065

PHOBOS KRFM Spectral Results: Surface Heterogeneity and Meteorite Analogs
D. T. Britt, S. L. Murchie, C. M. Pieters, J. W. Head, P. C. Fisher, S. F. Pratt, L. V. Ksanfomality, A. Zharkov, G. Nikitin, B. S. Zhukov, A. Kuzmin
  1066

Comparison of Asteroid and Meteorite Spectra by Principal Components Analysis
D. T. Britt, D. J. Tholen, J. F. Bell, C. M. Pieters
  1067

The Estherville Mesosiderite: A Polymict Breccia Formed 4.42 to 4.55 GA Ago: U-Pb, Rb-Sr, and Sm-Nd Isotopic Evidence
M. Brouxel, M. Tatsumoto
  1068

The Composition of Picogram to Milligram Meteoritic Spherules
D. E. Brownlee, L. S. Schramm
  1069

Radiation Damage in Germanium Detectors: Implications for the Gamma-ray Spectrometer of the Mars Observer Spacecraft
J. Bruckner, M. Korfer, H. Waenke, A. N. F. Schroeder, D. Filges, P. Dragovitsch, P. A. J. Englert, R. Starr, J. I. Trombka, I. Taylor, D. Drake, E. Shunk
  1070

Preliminary Results of High Resolution UV-Visible Spectroscopy of Lunar Red Spots
B. C. Bruno, P. G. Lucey, B. R. Hawke
  1071

Clast Populations in Three Antarctic Achondrites
B. C. Buchanan, A. M. Reid, C. Schwarz
  1072

Hypervelocity Impact Penetration Experiments--A Guide to the Origin of Rims on Chondrules
T. E. Bunch, P. Schultz, D. Brownlee, M. Podolak, R. Reynolds, P. Cassen, S. Chang
  1073

Chemical Evolution and Oxidative Weathering of Magmatic Iron Sulfides on Mars
R. G. Burns, D. S. Fisher
  1074

Mossbauer Spectra of Olivine-rich Weathered Achondrites: II. Brachina, Chassigny, ALHA 77005, and Nakhla
R. G. Burns, S. L. Martinez
  1075

Venus: Tectonic and Volcanic Consequences of Subduction and Underthrusting
J. D. Burt, J. W. Head
  1076

Physiographic Characteristics of Martian Drainage Basins
N. A. Cabrol
  1077

Analysis of Mariner 6 and 7 Spectra for Weak Absorption Features from 2 to 6 microns.
W. M. Calvin, T. V. V. King
  1078

Heating During Asteroidal Collisions
A. G. W. Cameron, W. Benz, J. T. Wasson
  1079

Volcanic Deposits in Western Eisila Regio: Preliminary Results of Radar Polarization Studies
B. A. Campbell, D. B. Campbell
  1080

High-Resolution Remote-Sensing Studies of Crater Ray Materials in Mare Serenitatis
B. A. Campbell, S. H. Zisk, J. F. Bell III, B. R. Hawke
  1081

Venus Southern Hemisphere: Age and Geologic Characteristics of Major Terrains in the THEMIS Regio-Alpha Regio-Lada Terra Region
D. B. Campbell, J. W. Head, D. A. Senske, A. A. Hine, N. J. Stacy, P. C. Fisher
  1082

Venus: Arecibo Radar Imagery from the 1988 Conjunction
D. B. Campbell, A. A. Hine, P. C. Fisher
  1083

A Method for the Extraction of Thermodynamic Properties of Alloys Which are Sparingly Soluble in Silicate Melts at High Temperature
C. J. Capobianco
  1084

Experimental Solubilities and Partitioning Behavior of Noble Metals Among Lithophile Magmatic Phases
C. J. Capobianco, M. J. Drake, P. S. Z. Rogers
  1085

The Effects of Floods, Volcanism and Polar Processes on the D/H Ratio in the Martian Atmosphere
M. H. Carr
  1086

KR and Xe Diffusion and Solubility in Silicate Melts and Glasses
M. R. Carroll, S. R. Sutton, D. Woolum, K. Lewtsky, P. S. Z. Rogers
  1087

Origin of Metal in Aubrites: Siderophile Element Abundances in Cm-Sized Nodules of Norton County
I. Casanova, H. E. Newsom, E. R. D. Scott, K. Keil
  1088

Crater Morphology Variations in the Elysium Region: Implications for Ice Distribution on Mars
J. A. Cave
  1089

Crosscutting, Periodically Spaced Wrinkle Ridges of Hesperia Planum
D. J. Chadwick, T. R. Watters, M. J. Tuttle
  1090

Experimental Determination of Oxide Activities in Silicate Melt: an Application to the Condensation of CAI Liquids
L. Chamberlin, J. R. Beckett, E. M. Stolper
  1091

Geologic Mapping of Lower Mangala Valles, Mars: Evidence of Flooding, Sapping, Debris Flow, and Volcanism
M. G. Chapman, K. L. Tanaka
  1092

Elysium Basin, Mars: Implications of a Deep, Intermittent Lake System
M. G. Chapman, D. H. Scott, K. L. Tanaka
  1093

A Possible K/T Impact Site at the India-Seychelles Boundary
S. Chatterjee
  1094

The Presence of Pd107 in the Early Solar System
J. H. Chen, G. J. Wasserburg
  1095

Multispectral Imaging of Crater Gassendi in Ten Bands (UV to Near-IR)
S. D. Chevrel, P. Pinet
  1096

Options for the Scientific Exploration of Mars in ESA
A. F. Chicarro
  1097

Mineral-Dependent Comminution During Impact Cratering
M. J. Cintala, F. Hoerz
  1098

Further Evidence for the Absence of Strong Magnetic Fields on the Achondrite Parent Body, and Implications for Heat Sources in the Early Solar System
S. M. Cisowski, J. R. Dunn, M. Fuller
  1099

Derivation of Mars Atmospheric Dust Opacities from Radiative Transfer Analysis of Viking IRTM Emission Phase Function Sequences
R. T. Clancy, S. W. Lee
  1100

Volatile Loss and Fractionation Trends in Eucrities
A. K. Clare, R. H. Hewins
  1101

The Distribution of Glass on the Moon
P. E. Clark, A. Basu
  1102

Nucleosynthesis Updates for Isotopic Anomalies
D. D. Clayton
  1103

Oxygen Isotopic Compositions of Ordinary Chondrites and Their Chondrules
R. N. Clayton, T. K. Mayeda, E. J. Olsen, J. N. Goswami
  1104

Clay-Hydrocarbon Mixtures: Spectral Properties and Implications for Remote Sensing Identification of Organic-bearing Surfaces
E. A. Cloutis
  1105

Cold Polar Deserts: Weathering Rates, Mechanisms, and Implications for Remote Sensing of Mars
E. A. Cloutis
  1106

Detection Limits for Remote Sensing Identification of Hydrocarbon-bearing Surfaces
E. A. Cloutis
  1107

Characteristics of the Martian Atmospheric Surface Layer
G. D. Clow, R. M. Haberle
  1108

Free Convection in the Martian Atmosphere
G. D. Clow, R. M. Haberle
  1109

A Planetary Small Missions Program Using Small Spacecraft
K. J. Cole, H. Feingold, J. McAdams, M. L. Stancati, J. R. French
  1110

Characterization of Metal Products of Silicate Melt Electrolysis
R. O. Colson
  1111

Redox Relationships in Silicate Melts and Silicate Melt Structure
R. O. Colson, C. R. Keedy
  1112

Scattering Properties and Minor Constituents in the Atmosphere of Mars from the ISM/Phobos Experiment
M. Combes, P. Drossart, Th. Encrenaz, E. Lellouch, J. Rosenqvist, J. P. Bibring, Y. Langevin, V. I. Morox, A. V. Grigoriev, N. F. Sanko, D. V. Titov
  1113

Image Processing/Analysis/Map Generation Using Image 1.22 on the Macintosh Computer
C. D. Condit
  1114

Calcium in Forsteritic Olivines in Type IA Chondrules: an Experimental Study
H. C. Connolly Jr., R. H. Hewins
  1115

The Reproduction of Chondrule Rims: A Preliminary Report
H. C. Connolly Jr., R. H. Hewins, J. S. Delaney
  1116

Pyroclastic Deposits in the Nectaris Region of the Moon
C. R. Coombs, B. R. Hawke, C. A. Peterson, P. G. Lucey
  1117

Regional Pyroclastic Deposits in the North-Central Portion of the Lunar Nearside
C. R. Coombs, B. R. Hawke, C. A. Peterson, S. H. Zisk
  1118

Distribution, Occurrence, and Crystallization of Chromite and Olivine in the Lowermost Peridotite Zone, Stillwater Complex, Montana
R. W. Cooper
  1119

Thermokarstic Depressions at the Mouth of Elysium Channels (Mars): New Evidence for the Presence of Massive Icy Beds
F. M. Costard
  1120

Rationale for a Mars Rover/Sample Return Mission to Chryse Planitia and the Viking 1 Lander
R. A. Craddock
  1121

Evidence for Widespread Resurfacing in the Martian Highlands
R. A. Craddock, T. A. Maxwell
  1122

Suspect Impact Structures in the United Republic of Tanzania
R. A. Craddock, T. F. Torries
  1123

Geologic History of the Southern Reaches of Mangala Valles, Mars
R. A. Craddock, J. R. Zimbelman, R. Greeley
  1124

Langmuir Probe Measurements of Impact-Generated Plasma
D. A. Crawford, P. H. Schultz
  1125

Fire and Ice on Triton: Models for Cryovolcanism and Glaciology
S. K. Croft
  1126

Physical Cryovolcanism on Triton
S. K. Croft
  1127

Triton: Geology and Geologic History
S. K. Croft
  1128

Styles of Volcanism, Tectonic Associations and Evidence for Magma-Water Interactions in Eastern Hellas, Mars
D. A. Crown, R. Greeley
  1129

Evolution of the East Rim of the Hellas Basin, Mars
D. A. Crown, K. H. Price, R. Greeley
  1130

Formation and Evolution of Plume Plateaus on Venus
L. S. Crumpler, J. W. Head
  1131

Calculation of Martian Gamma Ray Spectra
G. Dagge, P. Dragovitsch, D. Filges, J. Bruckner
  1132

Phosphates in the EL Sampal IIIA Iron Meteorite Have Excess Cr53 and Primordial Lead
A. M. Davis, E. J. Olsen
  1133

Effective Fassaite/Liquid Trace Element Distribution Coefficients for Type B CAI's
A. M. Davis, S. B. Simon, L. Grossman
  1134

Structure of Laima Tessera: Comparison with Earth's Oceanic Crust
A. V. Decharon, J. W. Head
  1135

Experimental Studies of Cathodoluminescence in Type 1 Chondrule Analogs
J. M. Dehart, G. E. Lofgren
  1136

Hydraulic Routing of the Maja Outflow Across Xanthe Terra
R. A. de Hon
  1137

Geologic Map of the Galaxias Region (MTM 35217) Northwest Elysium Region, Mars
R. A. de Hon, P. J. Mouginis-Mark
  1138

Cinder Cones on the Earth, Moon, Mars, and Venus: A Computer Model
J. Dehn, M. F. Sheridan
  1139

Laser-Fusion Ar40/Ar39 Ages of Acid Zhamanshinite
A. L. Deino, T. A. Becker, J. B. Garvin
  1140

Preliminary Petrographic Data for MAC88105: Anorthositic Microbreccia
J. S. Delaney
  1141

Petrography of Meteoritic VLT Basalt Breccia (87521) from Elephant Moraine, Antarctica
J. S. Delaney, S. R. Sutton
  1142

Constraints on the Highlands Source-Area of Lunar Meteorite ALHA 81005 Using Chemical Compositions of Glasses
J. W. Delano
  1143

Experimental Constraints on the Oxidation State of the Lunar Mantle
J. W. Delano
  1144

Geochemistry of Apollo 11 impact Glasses: Regolith Compositions
J. W. Delano, Y.-G. Liu, R. A. Schmitt
  1145

Sudbury Again: New and Old Isotope Data
A. Deutsch, P. Brockmeyer, D. Buhl
  1146

REE Partitioning Between Silicate Liquid and Immiscible Sulfide Liquid: The Origin of the Negative EU Anomaly in Aubrite Sulfides
T. L. Dickinson, G. E. Lofgren, G. A. McKay
  1147

Chesterfield Structure (Hudson Bay): Possible Astrobleme
R. S. Dietz, J. F. McHone
  1148

Investigation of Chemical Differentiation of Pyroxene During High-Temperature Pulsed Laser Heating. I. Bimodal Composition of Melt
Yu. P. Dikov, M. V. Gerasimov, L. M. Mukhin, F. Wlotzka
  1149

Investigation of Chemical Differentiation of Pyroxene During High-Temperature Pulsed Laser Heating. II. Chemical Composition and Structure of Condensate
Yu. P. Dikov, M. V. Gerasimov, L. M. Mukhin, F. Wlotzka
  1150

Minimum Estimates for Volume Removal from the Martian Fretted Terrain Between 270 deg W and 360 deg W
A. M. Dimitriou
  1151

Stratigraphy of the Ismenius Lacus SE Subquadrangle: Clues to an Upland/Lowland Boundary Forming Event?
A. M. Dimitriou
  1152

Laboratory Measurements of the Solid-state Greenhouse Effect in Glass Beads
R. W. Dissly, R. H. Brown, D. L. Matson
  1153

Video-Polarmetry of the Lunar Regolithic Surface
A. Dollfus
  1154

An Experimental Program to Study Impacts on Compressible Aggregates
B. Donn, D. Peak, S. Y. Lee, E. Fullar, L. Dankelman
  1155

Experimental Simulation of Martian Neutron Leakage Spectrum
D. M. Drake, S. Wender, R. Nelson, E. R. Shunk, W. Amian, P. Englert, J. Bruckner, M. Drosg
  1156

The Simpson Desert Depression--An Ancient Giant Impact Basin--Part 2
M. J. Duane, W. U. Reimold
  1157

The Structure and Composition of Taenite Particles in Two Type VI Ordinary Chondrites
C. E. Duffield, D. B. Williams, J. I. Goldstein
  1158

Planetary Ices: A Comparison of Rheologies at T<200 K
W. B. Durham, S. H. Kirby
  1159

A Gamma Ray Mode of the Alpha Particle Analytical Instrument
T. Economou, A. Turkevich
  1160

The X-ray Mode of the Alpha Particle Analytical Instrument
T. Economou, J. Iwanczyk, A. Turkevich
  1161

Possible Cinder cones Near the Summit of Pavonis Mons Mars
K. S. Edgett
  1162

Intercrater Sand on Mars: Physical Properties Related to Regional Winds, Sediment Supply
K. S. Edgett, P. R. Christensen
  1163

The Arsia Mons-Oti Fossae Thermal Anomaly: A Region with a Higher Thermal Inertia than the Rest of Tharsis
K. S. Edgett, J. R. Zimbelman
  1164

Photometric Techniques for Lander Site Certification
N. D. Efford
  1165

The Relationship Between Photometric Roughness and Fractal Dimension
N. D. Efford
  1166

Vigarano CAI 477B: Petrography and MG Isotopic Composition of the Core and Individual Rim Layers
A. El Goresy, C. Caillet, E. Zinner
  1167

Physico-Chemical State of Titan's Subsurface Layers
J. Eluszkiewicz, D. J. Stevenson
  1168

Simulation of Galactic Cosmic Ray Interactions with 'Martian soil': Implications for Cosmogenic Nuclide Studies and Planetary Gamma Ray Spectroscopy
P. A. J. Englert, D. M. Drake, E. R. Shunk, M. Drosg, R. C. Reedy, J. Bruckner
  1169

Determination of Spectral Units in the Syrtis Major-Isidis Planitia Region from Phobos/ISM Observations
S. Erard, J.-P. Bibring, Y. Langevin, M. Combes, S. Hurtrez, C. Sotin, J. W. Head, J. F. Mustard
  1170

Constraints Placed on Bulk Moon Composition from MG Isotope Fractionation in Vaporised Pyrolite
T. M. Esat, A. E. Ringwood
  1171

MG Isotope Fractionation in Lunar Soils
T. M. Esat, S. R. Taylor
  1172

MG Isotopic Composition of Chondrules from the Unequilibrated Ordinary Chondrite Semarkona
T. M. Esat, S. R. Taylor
  1173

Angrites LEW87051 and LEW86010: Transport Time to Earth and Comparison with Angra DOS Reis
O. Eugster
  1174

Lunar Meteorite MAC88105: History Derived from Cosmic-Ray Produced and Solar Wind Trapped Noble Gases
O. Eugster
  1175

Chinese and Other Chondrites: Exposure Ages, Radiogenic and Trapped Noble Gases and Mineralogy
O. Eugster, Th. Michel, D. Wang
  1176

Yield Strengths of Terrestrial, Martian and Lunar Flows: A Reassessment
S. A. Fagents, L. Wilson
  1177

Heat Flow vs. Atmospheric Greenhouse on Early Mars
F. P. Fanale, S. E. Postawko
  1178

On the Collisional Evolution of Asteroid Rotation Rates
P. Farinella, D. Davis, P. Paolicchi, A. Cellino, V. Zappald
  1179

Analysis of Poorly Crystalline clay Mineralogy: Near infrared Spectrometry versus X-Ray Diffraction
W. H. Farrand, R. B. Singer
  1180

Ammonia Depletion Mechanisms on Uranus
B. Fegley Jr.
  1181

New Chemical Models of the Atmosphere of Uranus. I. Carbon and Nitrogen Bearing Gases
B. Fegley Jr.
  1182

New Chemical Models of the Atmosphere of Uranus. II. Chemical Probes of Atmospheric Dynamics
B. Fegley Jr.
  1183

The Chemistry of Deuterium Bearing Gases in the Atmosphere of Uranus
B. Fegley Jr.
  1184

Water Cloud condensation in the Atmosphere of Uranus
B. Fegley Jr.
  1185

Lunar Volcanic Gases: Further Thermodynamic Modeling Results for the Transport of Trace Metals and Volatile Elements
B. Fegley Jr., D. Kong
  1186

Thermal Neutron Leakage from Martian Carbonates
W. C. Feldman, B. M. Jakosky
  1187

Predicting Extra-Terrestrial Lava Flow Morphology
J. Fink, N. Bridges
  1188

The Lewis Cliff Meteorite Stranding Area, Polar Ice Cores, and Wisconsin Period Impacts
E. L. Fireman
  1189

Guinevere Planitia, Venus: Radar Characteristics of Volcanic Plains
P. C. Fisher
  1190

Isotope Ratio Imaging of Interplanetary Dust Particles
R. H. Fleming, G. P. Meeker, F. Radicati di Brozolo, D. F. Blake, L. D. White
  1191

Chemical Purity of Proposed Capture Materials: Implications for Trace Element Analyses on Captured Particles
G. J. Flynn, S. R. Sutton
  1192

Element Abundances in Seven Particles from the Large Area Collectors
G. J. Flynn, S. R. Sutton
  1193

Evidence for a Bimodal distribution of cosmic Dust Densities
G. J. Flynn, S. R. Sutton
  1194

Strength in the Lithosphere of a Small Icy Satellite
O. Forni, A. Coradini, C. Federico
  1195

A Case for Martian Salars and Saline Lakes During the Noachian
R. D. Forsythe
  1196

Polyphase Noachian Tectonism of the Memnonia/Aeolis Region: Evidence for Greater Pre-Tharsis Lithospheric Mobility of Mars
R. D. Forsythe
  1197

A Discussion of Mars' Western Equatorial Dichotomy Boundary Zone: Enigmas, Anomalies and controversies
R. D. Forsythe, J. R. Zimbelman
  1198

Experimental Petrology of Dikes Related to Anorthosite complexes
M. S. Fram, J. Longhi
  1199

Two Possible Subduction Zones on Venus
S. L. Frank, J. W. Head
  1200

MEVTV Study: Early Tectonic Evolution of Mars--Crustal Dichotomy to Valles Marineris
H. Frey, R. A. Schultz
  1201

Are Noachian-age Ridged Plains (NPIR) Actually Early Hesperian in Age?
H. Frey, C. E. Doudnikoff, A. M. Mongeon
  1202

Hardness and Shape Irregularity of Metallic Particles in Antarctic Ordinary Chondrites
N. Fujii, Y. Horii, H. Takeda
  1203

Aircraft Radar Analyses of Flow Textures and Aeolian Mantling Deposits, Pisgah, CA
L. R. Gaddis, R. Greeley
  1204

Mineralogical Variations Within the S-Asteroid Population
M. J. Gaffey, J. F. Bell, R. H. Brown, T. Burbine
  1205

Sulfur Isotopic Studies in Meteorites
X. Gao, M. H. Thiemens
  1206

Topographic Cross-Sections and Interior Volumes of Craterform Structures
J. B. Garvin
  1207

Martian Surface Simulations
R. W. Gaskell
  1208

Shock-Induced Devolatilization of Noble Gases: Solid Recovery Experiments with Vitreous Carbon
C. A. Gazis, T. J. Ahrens
  1209

Exsolution of Spinel and Ilmenite in Magnetites from Type 4-5 Carbonaceous Chondrites-Indications for Metamorphic Processes
T. Geiger, A. Bischoff
  1210

Isotopic Composition of Osmium from a Mantle Volcano
M. Geissbuehler, U. Kraehenbuehl, F. Buehler, P. Eberhardt, D. L. Finnegan
  1211

Dark Materials in Valles Marineris: Indications of the Style of Volcanism and Magnetism on Mars
P. E. Geissler, R. B. Singer, B. K. Lucchitta
  1212

A Comparative Study of "Layer Silicate" Interplanetary Dust Particles (IDPs) and CI/CM Carbonaceous Chondrites
M. S. Germani, J. P. Bradley, D. E. Brownlee
  1213

Chloride Lavas: A Possible Magmatic Differentiation Product Under Anhydrous Conditions?
S. L. Gillett
  1214

Ejecta Fallout as a Killing Mechanism at the K-T Boundary: Evidence from a Volcanic Ash Layer
I. Gilmour
  1215

Does Wrinkle Ridge Formation on Mars Involve Most of the Lithosphere?
M. P. Golombek, J. Suppe, W. Narr, J. Plescia, B. Banerdt
  1216

Volatile Compounds in Shergottite and Nakhlite Meteorites
J. L. Gooding, K. E. Aggrey, D. W. Muenow
  1217

Sm-Nd Isotopic Systematics of Ureilites: A 3.74 GA Isochron for Kenna, Novo Urei, and ALHA77257
C. A. Goodrich, P. J. Panchett, G. W. Lugmair, M. J. Drake
  1218

Stable Isotope Geochemistry of MAC 88105: Comparison with Apollo Soils and Other Lunar Meteorites
M. M. Grady, C. T. Pillinger
  1219

Fractal Grainshape Analysis of Lunar Soils 67941 and 68501
J. Graf
  1220

Exposure Ages and Collisional History of L-Chondrite Parent Bodies
T. Graf, K. Marti
  1221

Amounts and Styles of Ejecta Erosion at Meteor Crater, Arizona
J. A. Grant, P. H. Schultz
  1222

Planetary Accretion Rates: Analytic Formulae Confirmed by a Variety of Numerical Simulations
R. Greenberg, W. F. Bottke
  1223

Description and Preliminary Tectonic Evaluation of the Eastern Ishtar Syntaxis of Venus
E. B. Grosfils, J. W. Head
  1224

Description and Preliminary Tectonic Evaluation of the Eastern Ishtar Syntaxis of Venus
E. B. Grosfils, J. W. Head
  1225

Use of Aircraft Multispectral and Multiple Emission Angle Data to Determine Surface Roughness and Composition at the Lunar Lake Playa in Nevada
E. A. Guinness, R. E. Arvidson, J. R. Irons, D. J. Harding
  1226

Valley Development on Mars: A Global Perspective
V. C. Gulick, V. R. Banker
  1227

A Compositional Study of Whole-Rock Fragments of the L6 Chondrite Bruderheim
J. R. Haas, L. A. Haskin
  1228

Origin of Anomalous Crater Chains and Their Implications for the Cratering Record
C. W. Halfen, P. H. Schultz, D. E. Gault
  1229

Lunar-type Pyroxenes in Terrestrial Tholeiites?
R. P. Hall, D. J. Hughes
  1230

Complex Pyroxenes in Wyoming Diabase Dikes: Lunar Analogues
R. P. Hall, D. J. Hughes, L. Joyner, G. L. Snyder
  1231

Zirconium Isotopes as an Astrophysical Probe of the Nucleosynthetic Source Conditions of Primitive Solar System "Components"
C. L. Harper, L. E. Nyquist, C.-Y. Shih, H. Weismann
  1232

On the Tidal Evolution of Binary Asteroids
A. W. Harris
  1233

PHOBOS and the Scattering of C Asteroids at the End of Planet Formation
W. K. Hartmann
  1234

Volatiles Present in Interplanetary Dust Particles and Contaminants Collected on the Large Area Collectors
C. P. Hartmetz, E. K. Gibson Jr.
  1235

LEW86018: A Rare L3. 1 Unequilibrated Ordinary Chondrite
C. P. Hartmetz, J. M. Dehart, F. A. Hasan
  1236

A Study of Aerogel's Suitability as an IDP Collection Substrate: Potential Solutions to Volatile Contamination Problems
C. P. Hartmetz, E. K. Gibson Jr., H. V. Lauer
  1237

Manson Impact Structure Rocks: Evidence for Impact Melting
J. B. Hartung, R. R. Anderson
  1238

The Best Cosmic Dust Source in the World? The Origin and Significance of the Walcott Neve, Antarctica Micrometeorites
R. P. Harvey, M. Maurette
  1239

Fragment of Terrestrial Origin in Regolith Breccia Sample 14313.108
L. A. Haskin, B. L. Jolliff, R. L. Korotev
  1240

Color Decorrelation for the PHOBOS Mission Camera Experiment
E. Hauber, G. Schwarz, P. Regner, K. Schmidt, G. Neukum
  1241

The Composition of the Crust in the Orientale Region of the Moon: A Pre-Galileo View
B. R. Hawke, P. D. Spudis, P. G. Lucey, J. F. Bell
  1242

Morphometry of Fresh Impact Craters in Hesperia Planum, Mars
J. Hayashi-Smith, P. J. Mouginis-Mark
  1243

Venus Crustal Formation and Evolution: an Analysis of Topography and Crustal Thickness Variations
J. W. Head
  1244

Venus Hypsometric Curve: an Assessment of its Components and Comparison to Earth
J. W. Head
  1245

The Danu Montes Deformation Zone of Southern Ishtar Terra: Evidence for Convergence and Crustal Underthrusting
J. W. Head, J. D. Burt
  1246

A Crustal Spreading/Mantle Plume Model for the Tectonics of Venus
J. W. Head, L. S. Crumpler
  1247

The Geology of Venus: A Pre-Magellan Synthesis and Key Questions for Magellan
J. W. Head, L. S. Crumpler
  1248

CE Anomalies in the Antarctic Eucrite LEW 85300
C. F. Heavilon, G. Crozaz
  1249

Oberon: Color Photometry and its Geological Implications
P. Helfenstein, J. Hillier, C. Weitz, J. Veverka
  1250

Comets Discovered by PCAS in 1989
E. F. Helin, B. P. Roman, J. T. Alu
  1251

The Martian South Polar Cap: Stability and Water Transport at Low Obliquities
B. G. Henderson, B. M. Jakosky
  1252

Weathering and Erosion of the Polar Layered Deposits on Mars
K. E. Herkenhoff
  1253

The Initiation of Subduction: Thermal and Compositional Considerations with Application to Venus
D. L. Herrick, E. M. Parmentier
  1254

Planform of Global Mantle Convection Pattern for Venus
R. R. Herrick, R. J. Phillips
  1255

Komatities and the Archean Mantle
P. C. Hess
  1256

Spreading Center Processes Under Venus Conditions: Implications for Crustal Formation, Petrology, and Structure
P. C. Hess, J. W. Head
  1257

Phosphate Equilibria in Lunar Basalts
P. C. Hess, P. Horzempa, M. J. Rutherford, J. Devine
  1258

Chondrule Evolution Revisited: Semarkona and Chainpur
R. H. Hewins
  1259

Geologic History of LEW 85300, 85302 and 85303 Polymict Eucrites
R. H. Hewins
  1260

Raman Study of Olivines in Thirty Seven Heavily and Moderately Shocked Ordinary Chondrites
D. Heymann
  1261

On the Location of the K/T Boundary Impact Site
A. R. Hildebrand, W. V. Boynton
  1262

Differential Thermal Stresses: A Source for Early Extensional Tectonism on the Saturnian and Uranian Satellites
J. K. Hillier, S. W. Squyres
  1263

The S-Type Reflectance Spectrum Simulated by a Chondrite and an Iron Meteorite
T. Hiroi, H. Takeda
  1264

Formation of Earth Atmosphere: Impact Degassing
H. Hiyagon, M. Ozima
  1265

Chemical Versus Mineralogical Influence on Reflectance Spectra of Andesitic Whole Rock Powders
H. Hoffmann, R. Jaumann, G. Neukum
  1266

Ammonia-Water Densities and Phase Relations to Four Kilobars
D. L. Hogenboom, J. S. Kargel
  1267

Comparative Xenology of Two Angrites
C. M. Hogenberg, T. J. Bernatowicz
  1268

Interstellar Noble Gas Components in Inman and Tieschitz
C. M. Hohenberg, R. H. Nichols Jr., C. M. O'd. Alexander, C. T. Olinger, J. W. Arden
  1269

Martian Magmas and Mantle Source Regions: Current Experimental and Petrochemical Constraints
J. R. Holloway
  1270

Long-Sought Primordial Fine-Grained Inclusion Discovered
B. B. Holmberg, A. Hashimoto
  1271

Scaling issues for Impact Cratering
K. A. Holsapple
  1272

Magnetic Effects of Large-Scale Impacts on Airless Planetary Bodies
L. L. Hood
  1273

Thin-film Penetration Experiments at Oblique Impact Angles
F. Hoerz, M. J. Cintala, R. P. Bernhard, F. Cardenas, J. Haynes, W. E. Davidson, T. H. See
  1274

Diffusion of Volatiles in Cometary Analogs
P. Hsiung, K. Roessler
  1275

Petrogenesis of Apollo 14 High (HA) Parental Basaltic Magma
S. S. Hughes, C. R. Neal, L. A. Taylor
  1276

Interstellar Diamonds and Silicon Carbide in Enstatite Chondrites
G. R. Huss, R. S. Lewis
  1277

Titan Radar Mapper for the Cassini Mission
E Im, C. Werner, L. Roth
  1278

Trace-Element Inventory of the Allende (CV3) Meteorite
T. R. Ireland, H. Palme, B. Spettel
  1279

A Temperature Rise Associated with Low Velocity Impact Experiments
T. Ishibashi, S. Kitabayashi, H. Azuma, N. Fujii, K. Sangen
  1280

Water Distribution on Martian Soils in Region Southward Olympus Mons, Mars (Preliminary Results)
M. A. Ivanov, V. I. Moroz, Yu. A. V. Grigoryev, V. Nicolsky, N. F. San'ko, I. V. Khatuntsev, A. V. Kiselev, J.-P. Bibring, M. Combes, Y. Langevin, A. Soufflot
  1281

Long Time Orbital Dynamics of Dust Grains from Comets: Encke and Halley
A. A. Jackson, H. A. Zook
  1282

On the Excess Lead in Carbonaceous Chondrites
E. Jagoutz, Q. Z. Yin, H. Waenke
  1283

The Thermal Inertia of Mars: Re-Interpretation Using a Better Atmospheric Model
B. M. Jakosky, R. M. Haberie
  1284

Mineralogy, Petrology and Chemistry of Splits from Lunar Ferroan Anorthosite 60025
O. B. James, J. J. McGee, M. M. Lindstrom
  1285

Finite Element Modeling of Venusian Coronae
D. M. Janes, H. J. Melosh
  1286

What's Wrong with Photoclinometry?
D. G. Jankowski, S. W. Squyres
  1287

Partitioning of Ni, P, Ir, AU and GE Between Taenite and P-rich Kamacite
P. E. Janney, J. H. Jones
  1288

Constraints on the Origin of Type II Chondrules from Chromite Compositions
C. A. Johnson, M. Prinz, M. K. Weisberg
  1289

Estimates of Lunar Mare Titanium Abundances from CCD Imaging and Spectroscopy
J. R. Johnson, S. M. Larson, R. B. Singer
  1290

Igneous Origin for NA in the Cloud of Io
M. L. Johnson, D. S. Burnett
  1291

Fragments of Quartz Monzodiorite and Felsite in Apollo 14 Soil Particles
B. L. Jolliff
  1292

General Petrography and Bulk Composition of Lunar Meteorite MAC88105
B. L. Jolliff
  1293

The Search for Igneous Precursors of Apollo 14 Impact Melt Breccias: Clues in Soil Particles
B. L. Jolliff
  1294

Petrography and Geochemistry of Ferroan Troctolitic Anorthosite in Lunar Meteorite MAC88105
B. L. Jolliff, L. A. Haskin, R. L. Korotev
  1295

Thermal Diffusion in Fe-Ni-S-P Metallic Liquids
J. H. Jones, D. Walker
  1296

Experimental Constraints on the Composition of the Eucrite Parent Body
J. H. Jones, C. R. Paslick, G. A. McKay
  1297

Thermal Metamorphism in CO3 Chondrites: Application of Olivine Diffusion Modelling to Post-Accretionary Metamorphism
R. H. Jones, D. C. Rubie
  1298

Further Evidences for Horizontal Block/Plate Movements or Nappe Tectonics Within the Tanova Updoming, Mars
H.-P. Jons
  1299

The Planet Mars: Presentation of a Global Map
H.-P. Jons
  1300

Carbon-14 Terrestrial Age of the MAC88105 Lunar Meteorite
A. J. T. Jull, D. J. Donahue
  1301

Terrestrial Age and Petrologic Type of Meteorites from the Libyan Desert
A. J. T. Jull, F. Wlotzka, H. Palme, D. J. Donahue
  1302

Radar Observations of Tinatin Planitia: Goldstone 1988 Observations of Venus
R. F. Jurgens, C. Franck, W. Greiner, D. Howard, L. Robinett, M. A. Slade, K. Wyss, R. E. Arvidson, J. Plaut
  1303

Scientific and Engineering Applications of the Mars-Global Reference Atmospheric Model (Mars-GRAM)
C. G. Justus, B. James
  1304

Ancient Glaciation on Mars
J. S. Kargel, R. G. Strom
  1305

Cryovolcanism on Triton
J. S. Kargel, R. G. Strom
  1306

Pre-Accretion Irradiation of Crystals in the Tieschitz H3.6 Chondrules
L. L. Kashkarov, G. V. Kalinina
  1307

Chondrule Thermoluminescence: Implication for the Thermal History of Type 3-5 Ordinary Chondrites
L. L. Kashkarov, V. G. Kashkarova
  1308

Thermoluminescence and Track Parameters for the Chondrules from the Tieschitz H3.6 Ordinary Chondrite
L. L. Kashkarov, G. V. Kalinina, V. G. Kashkarova, G. V. Baryshnikova
  1309

Thermoluminescence Dating of Glasses from Zhamanshine Crater
L. L. Kashkarov, V. G. Kashkarova, E. P. Izokh
  1310

Study of Nikol'skoe L4-5 Chondrite Olivine Chondrule by Track and Thermoluminescence Methods
L. L. Kashkarov, N. N. Korotkova, V. G. Kashkarova, A. Ya. Skripnik
  1311

The Glass Inclusions from Kaidun CV2 Carbonaceous Chondrite as Indicator of Its Thermal History on Data of Track and TL Studies
L. L. Kashkarov, N. N. Korotkova, V. G. Kashkarova, A. Ya. Skripnik
  1312

Venus: A Contrast in Evolution to the Earth
W. M. Kaula
  1313

Volcanic Centers in Northern Lavinia Planitia
S. T. Keddie, J. W. Head, D. B. Campbell
  1314

A Study of Redox Behavior of NI in Silicate Melts of Diopsidic to Anorthitic Composition
C. R. Keedy, R. O. Colson, L. A. Haskin
  1315

Aqueous Alteration Products in CV3 and CO3 Carbonaceous Chondrite Meteorites: Phyllosilicates
L. P. Keller, P. R. Buseck
  1316

Trace Element and Isotopic Constraints on the Formation and Crystallization of a Type BL CAI from Allende
A. K. Kennedy, J. R. Beckett, I. D. Hutcheon
  1317

Lunar and Solar Nitrogen from 3.7 GYR Ago
J. F. Kerridge, O. Eugster, J. S. Kim, K. Marti
  1318

Why are the Carrizizo Lava Flows 75 KM Long?
L. P. Keszthelyi, D. Pieri
  1319

Optical Constants of Kerogen from 0.15 to 40 microns: Comparison with Meteoritic Organics
B. N. Khare, W. R. Thompson, C. Sagan, E. T. Arakawa, C. Meisse, I. Gilmour
  1320

Crustal Convergence and Mantle Downwelling in the Ishtar Terra Region of Venus
W. S. Kiefer, B. H. Hager
  1321

Diffusion Kinetics of Solid Methane and Nitrogen: Implications for Triton
R. L. Kirk
  1322

Thermal Models of Insolation-Driven Nitrogen Geysers on Triton
R. L. Kirk
  1323

Average SCR Flux During Past 105 Years: Inference from 41Ca in Lunar Rock 74275
J. Klein, D. Fink, R. Middleton, S. Vogt, G. F. Herzog, R. C. Reedy, J. M. Sisterson, A. M. Koehler, A. Magliss
  1324

Olivine Compositions in Anhydrous and Hydrated IDPs Compared to Olivines in Matrices of Primitive Meteorites
W. Kloeck, K. L. Thomas, D. S. McKay, M. E. Zolensky
  1325

Radar-bright Haloes of Loukha Plantia: Implications for Venus Volcanic Style
K. B. Klose
  1326

Angular Distribution and Velocities of Dust Emissions Observed at Artificial Comets
H. Kochan, K. Seidensticker, W. Koerver
  1327

Post-Flooding Modifications to Chryse Basin Channels, Mars: Implications for Sources Volumes and Evolution of the Channels
R. C. Kochel, J. R. Miller
  1328

MAC88105--A New Meteorite from the Lunar Highlands: Preliminary Mineralogical, Petrological, and Geochemical Studies
C. Koeberl, G. Kurat, F. Brandstaetter
  1329

Roter Kamm Impact Crater, SWA/Namibia: New Geochemical and Isotopic Studies and Further Evidence for Post-Impact Hydrothermal Activity
C. Koeberl, W. U. Reimold, J. Bishop, R. McG. Miller
  1330

Current Results of Potassium-Argon Dating of the Kara Impact Structure
E. M. Kolesnikov, M. A. Nazarov, D. D. Badjukov, L. M. Lebedeva, V. L. Myasnikova
  1331

Layered Deposits with Volcanic Instructions in Gangis Chasma, Mars
G. Komatsu, R. G. Strom
  1332

A Hydrodynamic Model of Dusty Gas Flows in Comet Comae with Dust Fragmentation
I. Konno, W. F. Huebner, D. C. Boice
  1333

Relationship of Poroshity and Impact Melt Rocks Composition (Zhamanshin Astrobleme, USSR)
N. N. Korotayeva, L. V. Sazonova
  1334

Are Apollo 16 Soils Foreign to the Apollo 16 Site?
R. L. Korotev
  1335

Correction for Loss of Metallic Iron in "Fused-Bead" Analysis of Metal-Bearing Silicate Samples
R. L. Korotev
  1336

Provenance of Ropy Glasses from Shorty Crater at Apollo 17
R. L. Korotev
  1337

Compositional Survey of Particles from the Luna 16 Regolith, part 2
R. L. Korotev, B. L. Jolliff, L. A. Haskin
  1338

Compositional Survey of Particles from the Luna 24 Regolith
R. L. Korotev, B. L. Jolliff, L. A. Haskin
  1339

Preliminary Report on Geochemical Study of Lunar Meteorites MAC88104 and MAC88105
R. L. Korotev, B. L. Jolliff, L. A. Haskin
  1340

Roughness of Lava Flows in Sedna Planitia (Venus)
M. A. Kreslavsky, V. P. Kryuchkov
  1341

Evidences of Eastward Displacements on the Surface of Venus
V. P. Kryuchkov
  1342

Early Thermal History and Atmospheric Evolution of Titan
K. Kuramoto, T. Matsui
  1343

Variation of the Bound Water Contents on the Martian Surface from ISM-Experiment Data on Phobos-2: Preliminary Results
R. O. Kuzmin, V. I. Moroz, Yu. A. V. Grigoryev, Y. V. Nikolsky, N. F. San'ko, I. V. Khatuntsev, A. V. Kiselev, J.-P. Bibring, Y. Langevin, A. Soufflot, M. Combes
  1344

Distribution of Impact Induced Phenomena in Complex Terestrial Impact Structures: Implications for Transient Cavity Dimensions
R. Lakomy
  1345

Implications for Cratering Mechanics from Breccias in the Basement of the Subbury Impact Crater, Canada
R. Lakomy
  1346

Organic Compounds in Cometary Dust: Their Chemical Systematics Using Similarity of Molecular Graphs
B. Land, T. Grochowski
  1347

Observations of PHOBOS from 8 to 3.15 microns with the ISM Experiment On-Board the Soviet "Phobos II" Spacecraft
Y. Langevin, J.-P. Bibring, B. Gondet, M. Combes, A. V. Grigoriev, B. Joukov, Y. V. Nikolsky
  1348

Actinide Element Fractionation in Solar System Processes: The Role of Oxygen Fugacity
T. Z. La Tourrette, M. L. Johnson, D. S. Burnett
  1349

Inspection of the Long Duration Exposure Facility and Plans to Characterize the Dust Environment in Low-Earth Orbit
Ldef Meteoroid, Debris Spec. 
  1350

The Effects of Atmospheric Dust on Observations of the Surface Albedo of Mars
S. W. Lee, R. T. Clancy
  1351

Numerical Simulations of Mantle Convection of Venus
A. M. Leitch, D. A. Yuen
  1352

Orbital Evolution of a Triton Captured by Gas Drag
A. C. Leith, W. B. McKinnon
  1353

The Utility to Geochemistry of Inductively Coupled Plasma Mass Spectrometry (ICP-MS) with Laser Ablation: A Progress Report
F. E. Lichte, W. I. Ridley
  1354

Solar and IR Radiation Near the Martian Surface: A Parameterization for CO2 Transmittance
B. L. Lindner, T. P. Ackerman, J. B. Pollack, O. B. Toon, G. E. Thomas
  1355

Compositional Variations in Cosmic Dust-sized Pieces of Murchison Matrix
D. J. Lindstrom, M. E. Zolensky, R. R. Martinez
  1356

INAA of Cosmic Dust Particles from the Large Area Collector
D. J. Lindstrom, M. E. Zolensky, R. R. Martinez
  1357

A Geochemical-Petrologic Study of the Populations of Coarse-fines Particles in Apennine Front Soils
M. M. Lindstrom, U. B. Marvin
  1358

Geochemistry of Lunar Meteorites MAC88104 and MAC88105
M. M. Lindstrom, R. R. Martinez, D. W. Mittlefehldt
  1359

Multivariate Statistical Analysis of Compositional Data from Ordinary Chondrites
M. E. Lipschutz, S. M. Samuels
  1360

Fluids in Depleted Mantle and Origin of Diamonds
K. I. Lochov, L. K. Levsky
  1361

Fractionation of REE During Aubrite Formation: The Influence of FeS and CaS
K. Lodders, H. Palme
  1362

The Crystallization of a Melt Droplet Chondrule
G. E. Lofgren
  1363

Dynamic Crystallization Characteristics of ADOR
G. E. Lofgren, A. B. Lanier
  1364

Magmatic Processes on Mars: Insights from SNC Meteorites
J. Longhi
  1365

Isotope Anomalies in Vigarano CAI's - HIC et Ubique
R. D. Loss, G. W. Lugmair, G. J. MacPherson, A. M. Davis
  1366

Semarkona Type I Chondrules Compared with Similar Chondrules in Other Classes
J. Lu, D. W. G. Sears, B. D. Keck, M. Prinz, J. N. Grossman, R. N. Clayton
  1367

Valles Marineris, Mars: Are Pit Chains Formed by Erosion and Troughs by Tectonism?
B. K. Lucchitta, R. A. Blaser, L. M. Bertolini
  1368

Comparison of Thermal Emission Spectroscopic Measurements of the Lunar Surface
P. G. Lucey
  1369

Preliminary Results of Imaging Spectroscopy of the Humorum Basin Region of the Moon
P. G. Lucey, B. R. Hawke, B. C. Bruno
  1370

A Physical Model of the Impacted Martian Crust: Hydrologic and Mechanical Properties and Geologic Implications
D. J. MacKinnon, K. L. Tanaka
  1371

Intact Planetoid Capture: Identification of Some Favourable Capture Orientations for a Lunar-Like Planetoid
R. J. Malcuit, D. M. Mehringer, R. R. Winters
  1372

On the Formation of Cometary Atmosphere
M. Ya. Marov, A. V. Kolesnichenko, Yu. V. Skorov
  1373

Volatile Molecules Produced from Carbides of Iron, Calcium, and Manganese by Laser Pulse
C. Marquez, C. P. Hartmetz, E. K. Gibson Jr., J. Oro
  1374

Mossbauer Spectra of Olivine-rich Weathered Achondrites: I Ureilites
S. L. Martinez, R. G. Burns
  1375

New Pieces of the Lunar Granite-Quartz Monzodiorite Puzzle
U. B. Marvin, B. B. Holmberg, M. M. Lindstrom
  1376

Evolution of Proto-CO2-Atmosphere on the Earth
T. Matsui, E. Tajika
  1377

Measurement of the Volatile Component in Particles Emitted from an Artificial Comet
K. Mauersberger, H.-J. Michel, D. Krankowsky, P. Lammerzahl, P. Hesselbarth
  1378

Martian Crater Counts on Elysium Mons
K. McBride, N. G. Barlow
  1379

Small Volcanic Features in Western Elysium Plantia
K. McBride, J. R. Zimbelman
  1380

Slope Properties of Some Terrestrial Surfaces and Implications for Planetary Radar Interpretation
T. M. McCollom, B. M. Jakosky
  1381

Metallographic Cooling Rates Correlated with Petrologic Type in LL3.0-4 Chondrites: Implications for Parent Body Structures
T. J. McCoy, G. J. Taylor, E. R. D. Scott, K. Keil
  1382

First Results from LDEF's Multiple Foil Microabrasion Package
J. A. M. McDonnell, T. J. Stevenson
  1383

Development of the Southwest Elysium Canyon Complex, Mars
J. H. McDonnell
  1384

Global Color and Albedo Variations on Triton
A. S. McEwen
  1385

Valles Marineris Landslides: Evidence for Mechanics of Large Rock Avalanches
A. C. McEwen
  1386

Olivine, Beta Spinel and Majorite/Melt Partitioning and the Early Thermal History of the Earth
E. A. McFarlane, M. J. Drake, C. Herzberg
  1387

Mineralogy and Compositional Variations in Lunar Ferroan Anorthosites
J. J. McGee
  1388

Polygonal Terrane of Mars: Stresses from Drape Folding
G. E. McGill, L. S. Hills
  1389

State of Stresses and Eruption Characteristics of Martian Volcanoes
P. J. McGovern, S. C. Solomon
  1390

Light Scattering by Large, Irregular Particles
A. V. McGuire, B. Hapke
  1391

Natural Reduction of Lunar Iron Oxide
D. S. McKay, S. J. Wentworth
  1392

A Petrographic, Electron Microprobe, Study of Mini-Angrite Lewis Cliff 87051
G. McKay, G. Crozaz, I. Wagstaff, S. R. Yang, L. Lundberg
  1393

REE Distribution Coefficients for Pigeonite: Constraints on the Origin of the Mare Basalt Europium Anomaly
G. McKay, J. Wagstaff, L. Le
  1394

Diffusion of Oxygen in Diopside and Spinel: Implications for Oxygen Isotopic Anomalies in CAls
K. D. McKeegan, F. J. Ryerson
  1395

Triton's Post-Capture Thermal History
W. B. McKinnon, L. A. M. Benner
  1396

Kinetic Pathways to Chondrite Petrologic Types
H. Y. McSween Jr.
  1397

Evidence for Low Temperature Equilibration in Allende CAI
G. P. Meeker
  1398

On the Ablation of Flanged Australian Tektites
W. L. Melinik, J. A. O'Keefe
  1399

On the Origin of the Carbon-rich Aggregates in the Ordinary Chondrites
R. A. Mendybaev, N. S. Kuyunko, M. V. Mironenko, A. K. Lavrukhina
  1400

Volcanism and Tectonics on Venus and Earth
Z. U. Mian, D. C. Tozer
  1401

Chromite and Ilmenite in the Eucrite Pomozdino
L. F. Migdisova, A. A. Yaroshevsky
  1402

Geochemistry of LEW87051 and Comparison of the Angrites
D. W. Mittlefehldt, M. M. Lindstrom
  1403

Mineralogical Data of Shocked Quartz Grains from K-T Boundary
Y. Miura
  1404

Pagioclase (-like) Compositions of Yamato-691 Chondrite
Y. Miura, Y. Hanaura
  1405

Heating Experiments (300-700.C) of the Murchison (CM2) Meteorite: Infrared Spectroscopy
M. Miyamoto
  1406

Infrared Diffuse Reflectance Spectra of Some Antarctic Carbonaceous Chondrites
M. Miyamoto
  1407

Infrared Diffuse Reflectance Spectra of Some Hydrous Carbonates
M. Miyamoto, A. Kato
  1408

Continental Drift on Venus?
H. Mizutani, A. Fujimura, R. Moroto
  1409

Analyses and Morphology of a Lava Flow, Ascraeus Mons, Mars
H. J. Moore, P. A. Davis
  1410

Surface-Material Maps of Viking Landing Sites on Mars
H. J. Moore, J. M. Keller
  1411

Rhenium-Osmium Isotope Systematics in Enstatite Chondrites
J. W. Morgan, R. J. Walker, J. N. Grossman
  1412

Iron Mineralogy of a Hawaiian Palagonitic Soil with Mars-like Spectral and Magnetic Properties
R. V. Morris, J. L. Gooding, H. V. Lauer Jr., R. B. Singer
  1413

Can Metastable Sulfur Allotropes Exist on Io?
J. I. Moses, D. B. Nash
  1414

Evolution of the Olympus Mons Caldera, Mars
P. J. Mouginis-Mark, M. S. Robinson, M. T. Zuber
  1415

Illmenite in High-Ti Apollo 17 Basalts: Variations in Composition with Degree of Exsolution
T. Muhich, D. Vaniman, G. Heiken
  1416

Relationship of Decan Volcanism to Global K-T Biotic Extinctions: A Case of Unfounded Assumptions?
A. V. Murali, D. P. Blanchard, N. Bhandari, J. D. MacDougall
  1417

Ramgarh Crater, Rajasthan, India: Study of Multispectral Data Obtained by Indian Remote Sensing Satellite (IRS-IA)
A. V. Murali, S. Williams, K. Lulla
  1418

Calibration of Multicolor TV Imaging and KREFM Spectrometer Observations of PHOBOS
S. L. Murchie, D. Britt, J. Head, S. Pratt, P. Fisher, B. Zhukov, A. Kuzmin, L. Ksanfomality, G. Nikitin, A. Zharkov, F. Fanale, D. Blaney, M. Robinson
  1419

Color Variations on the Surface of PHOBOS and Their Relationship to Geologic Features
S. L. Murchie, D. Britt, J. Head, S. Pratt, P. Fisher, B. Zhukov, A. Kuzmin, L. Ksanfomality, G. Nikitin, A. Zharkov, F. Fanale, D. Blaney, M. Robinson
  1420

Updated Mapping of the Surface of PHOBOS Using PHOBOS 2 Images: A Progress Report
S. L. Murchie, J. W. Head, B. S. Zhukov
  1421

Cosmogenic Nitrogen in Kapoeta: an Attempt to Isolate Solar Cosmic Ray Produced Component
S. V. S. Murty
  1422

Clathrate Storage of Volatiles on Mars
D. S. Musselwhite, J. I. Lunine
  1423

Early Outgassing of the Earth and Mars: Inferences from the Geochemical Behaviour of Iodine and Xenon
D. S. Musselwhite, M. J. Drake, T. D. Swindle
  1424

Interpretation of Spectral Units of Isidis-Syrtis Major from ISM-Phobos-2 Observations
J. F. Mustard, J.-P. Bibring, S. Erard, E. M. Fischer, J. W. Head, S. Hurtrez, Y. Langevin, C. M. Pieters, C. J. Sotin
  1425

Vaporization Experiments in the System Plagioclase-Hydrogen: 2 Composition of the Gas
H. Nagahara
  1426

Non-Axisymmetric Gravitational Instabilities in a Dust Layer in a Solar Nebula
Y. Nakagawa, M. Sekiya
  1427

Disk Self-Gravity Effects on the Time Evolution of the Solar Nebula
T. Nakamoto, Y. Nakagawa
  1428

Thermal Evolution of Venus Mountain Belts
N. Namiki, S. C. Solomon
  1429

Infrared Reflectance Spectra of Plagioclase Feldspars
D. B. Nash, J. W. Salisbury
  1430

The Kara Impact Structure: Distribution of Shocked Quartz Grains Through the Suevite Complex
M. A. Nazarov, D. D. Badjukov, I. V. Suponeva, A. S. Alekseev
  1431

The Kara Impact Structure: Iridium Abundances in the Crater Rocks
M. A. Nazarov, L. D. Barsukova, D. D. Badjukov, G. M. Kolesov, I. V. Nizhegorodova
  1432

"REEP" Metasomatism of the Apollow 14 Highlands: Evidence from the Mg-Suite
C. R. Neal, L. A. Taylor
  1433

Strontium Isotope and Major Element Evidence for AFC in the Petrogenesis of Apollo 14 High-Alumina Basalts
C. R. Neal, L. A. Taylor
  1434

Two New Type C Basalts: Petrogenetic Implications for Source Evolution and Magma Genesis at the Apollo 17 Site
C. R. Neal, J. B. Paces, L. A. Taylor, S. S. Hughes, R. A. Schmitt
  1435

The Importance of Fractional Crystallization in the Petrogenesis of Apollo 17 Type A and B High-Ti Basalts
C. R. Neal, L. A. Taylor, S. S. Hughes, R. A. Schmitt
  1436

An Apollo 17 Safari: Exciting New Clasts from Breccia "Pull-Apart" Efforts
C. R. Neal, L. A. Taylor, A. D. Patchen
  1437

New Lunar Meteorite MAC88105: A Ferroan Anorthosite Breccia with Mare Tendencies
C. R. Neal, L. A. Taylor, A. D. Patchen
  1438

The Dichotomy Between Primitive Highland Cumulates and Evolved Interstitial Whitlockites: The Process of "REEP-Fraction" Metasomatism
C. R. Neal, L. A. Taylor, A. D. Patchen
  1439

Production of Evolved Planetary Crust Through Partial Melting of Basalt
D. O. Nelson, W. C. Phinney
  1440

Open-System Evolution of Basaltic Magmas Emplaced in a Predominantly Mafic Crust: Matachewan Dikes, Superior Province of Canada
D. O. Nelson, W. C. Phinney, D. A. Morrison
  1441

Sensitivity of Hapke Modeling of Mixtures to Grain Size
M. L. Nelson
  1442

Non-Mass Dependent Oxygen Isotopic Fractionation During the Condensation of Simple Oxide Smokes
R. N. Nelson, W. D. Qing, M. H. Thiemens, J. A. Nuth III
  1443

Radiative Processes in the Earth's Atmosphere Resulting from Comet Impact
I. V. Nemtchinov, V. V. Svetsov
  1444

Geochemical Constraints on the Origin of the Moon
H. E. Newsom, T. B. Beserra
  1445

Impact Cratering on Mars and the Formation of Crater Lakes: A Possible Environment for the Origin of Life
H. E. Newsom, G. E. Brittelle
  1446

Allende Chondrules and Rims: I-Xe Systematics
R. H. Nichols Jr., C. M. Hohenberg, C. T. Olinger, A. E. Rubin
  1447

Anomalous KR and Xe Adsorption on Lunar Anorthositic Breccia 65315
S. Niedermann, O. Eugster
  1448

Helium and Neon Isotopes in Individual Stratospheric Particles--A Further Study
A. O. Nier, D. J. Schlutter
  1449

Formation Model of Northern Fan of Ridge Belts, Venus
A. M. Nikishin
  1450

Ishtar Terra on Venus: Stages of Formation
A. M. Nikishin
  1451

Preliminary Tectonic Map of Venus
A. M. Nikishin
  1452

Crustal Dichotomy: Universal for Terrestrial Planets?
O. V. Nikolaeva, M. A. Ivanov, V. K. Borozdin
  1453

Depth Profile of 41Ca in the Apollo 15 Long Core
K. Nishiizumi, J. R. Arnold, D. Fink, J. Klein, R. Middleton
  1454

New Results on History of Gardening in Lunar Cores 15008 and 76001 Using Cosmogenic Radionuclides
K. Nishiizumi, J. R. Arnold, P. W. Kubik, P. Sharma
  1455

Exposure Histories of Lunar Meteorites MAC88104 and MAC88105
K. Nishiizumi, J. Klein, D. Fink, R. Middleton, P. W. Kubic, P. Sharma, R. C. Reedy, J. R. Arnold
  1456

Trace Element Geochemistry of Lunar Breccia 67016
M. D. Norman, S. R. Taylor
  1457

New Measurements on the Physico-Chemical Properties of Natrocarbonatite Lavas
G. E. Norton, H. Pinkerton, J. B. Dawson
  1458

Ar-Ar, Rb-Sr, and Sm-Nd Studies of Eucritic Clast LEW85300.55
L. E. Nyquist, D. D. Bogard, B. M. Bansal, H. Wiesmann, C.-Y. Shih
  1459

A Model for Chemical Evolution of Life on Mars
V. R. Oberbeck, J. R. Marshall, D. E. Schwartz
  1460

Search for Life: A Science Rationale for a Permanent Base on Mars
V. R. Oberbeck, J. R. Marshall, D. E. Schwartz, R. L. Mancinelli
  1461

Recovery of Photometric Functions from Monoscopic Images of Craters--A Feasibility Study
J. Oberst, P. Regner, G. Neukum
  1462

Stability, Composition and Phase Relations of Martian Mantle Carbonates
M. I. Odezynskyi, J. R. Holloway
  1463

Collisional Dynamics of Ring Particles in the Gravitational Field of Saturn
K. Ohtsuki
  1464

Large Scale Oblique Impacts on the Earth
J. D. O'Keefe, T. J. Ahrens
  1465

Implanted Solar Neon in Greenland Micrometeorites
C. T. Olinger
  1466

Heat Loss by Basaltic Crust Formation on Venus
P. Olson, S. Weinstein, Z. Ying
  1467

S-Process Material in Murchison: SR and More on BA
U. Ott, F. Begemann
  1468

224Pu Fissiogenic Xe in Mantle
M. Ozima, S. Azuma, S. Zashu, H. Hiyagon
  1469

Resolution of Ages and Sr-Nd Isotopic Characteristics in Apollo 17 High-Ti Basalts
J. B. Paces, S. Nakai, C. R. Neal, L. A. Taylor, A. N. Halliday, D.-C. Lee, M. L. McKinney
  1470

Open-and Closed-System Magma Evolution of Apollow 17 High-Ti Basalts and Origin of Source Heterogeneities at 4.1 Ga: Sr-Nd Isotopic Evidence
J. B. Paces, C. R. Neal, S. Nakai, L. A. Taylor, A. N. Halliday
  1471

Neon in Material Separates of the Allende and Orgueil Meteorites
R. L. Palma, D. Heymann
  1472

Big MAC, Little MAC and the Composition of the Lunar Crust
H. Palme, B. Spettel, A. Burghele, G. Dreibus, G. Weckwerth, H. Waenke, K. P. Jochum, H. Weber, A. Bischoff, D. Stoeffler
  1473

RELICT Grains in a Ca-Al-rich Inclusion from Allende
J. M. Paque
  1474

Dike Emplacement in Volcanic Rift Zones
E. A. Parfitt
  1475

Constraints on the Partial Melt Model of Eucrite Genesis Through Investigation of SC Partition Coefficients for Olivine and Pyroxene
C. R. Paslick, J. H. Jones, G. McKay
  1476

Toward an Understanding of the Bulk Composition of Thick Stillwater Anorthosite Unit AN-II
K. D. Pass, P. A. Salpas
  1477

Adsorption of Nebular Gases on Protoplanetary Cores
R. O. Pepin
  1478

Noble Gas Components and Mineral Inclusions in Chondritic Metal: The Early History of FeNi
C. Perron, B. M. Denise, J. S. Kim, K. Marti, P. Pellas, G. Sagon
  1479

Chromite-Troilite Distribution of Fe and CR in Highly Shocked Chondrite Novosibirsk (H4-5)
M. I. Petaev
  1480

The Divnoe Meteorite. V. Classification, Proposed Genesis, Relation with Other Meteorite Types
M. I. Petaev, N. I. Zaslavskaya
  1481

The Divnoe Meteorite. III Bulk Chemistry
M. I. Petaev, L. D. Barsukova, G. M. Kolesov, N. I. Zaslavskaya
  1482

The Divnoe Meteorite. IV. Oxygen Isotopes and Track Studies
M. I. Petaev, V. I. Ustinov, V. P. Perelygin, Yu. A. Shukolyukov
  1483

Spectral Emissivity of the Silver and Lunar Lake Playas - Relevance to Analyses of Mars TIR Data
S. B. Petroy, R. E. Arvidson
  1484

Erosional Landforms and Morphotectonic Development in Valles Marineris (Mars): Melas Chasma
J. P. Peulvast
  1485

Geophysics at Mars: Issues and Answers
R. J. Phillips
  1486

Generation of Basaltic Crust on Venus
R. J. Phillips, R. E. Grimm
  1487

Anorthosites, Melts and the Bulk Moon
W. C. Phinney
  1488

Petrology of the Olivine Mountains at Copernicus
C. M. Pieters, S. F. Pratt, J. M. Sunshine
  1489

Thermal Erosion--Observations on Terrestrial Lava Flows and Implications for Planetary Volcanism
H. Pinkerton, L. Wilson, G. Norton
  1490

Radar Backscattering Behavior in the Equatorial Region of Venus--Goldstone Observations
J. J. Plaut, R. F. Jurgens
  1491

Photoclinometric Analysis of Wrinkle Ridges on Lunae Planum, Mars
J. B. Plescia
  1492

Young Flood Lavas in the Elysium Region, Mars
J. B. Plescia
  1493

Chondrite Chronology by Initial 87Sr/86Sr in Phosphates?
F. A. Podosek, J. C. Brannon
  1494

Formation of Rhyolitic Ridges on Martian Basalts
T. K. Porter, P. H. Schultz
  1495

The Cratering Record and Geological History of Enceladus
S. Pozio, J. S. Kargel
  1496

PB Isotopes in Norite 78235
W. R. Premo, M. Tatsumoto
  1497

LEW 87051, a New Angrite: Origin in a Ca-Al-enriched Eucritic Planetesimal?
M. Prinz, M. K. Weisberg, C. E. Nehru
  1498

Relationship Between Extinct and Live Chronometers: Sm-Nd in Meteorites
A. Prinzhofer, D. A. Pupanastassiou, G. J. Wasserburg
  1499

Titanium Isotopes in Allende Fine Grained Inclusions
C. A. Prombo, L. E. Nyquist, H. Weismann
  1500

Petrography and Bulk Compositions of Allende Fine Grained Aggregates
C. A. Prombo, S. V. Yang, P. C. Buchanan
  1501

Lakshmi Planum on Venus: Locus Convergence or Radial Spreading?
A. A. Pronin
  1502

Tectonics of Ridge Belt-Protocoronae Association of Ganiki Planitia on Venus
J. Raitala, K. Kauhanen
  1503

Rotational, Strike-Slip and Compressional Aspects of the Tectonics of Meshkenet Tessera on Venus
J. Raitala, T. Tormanen
  1504

Activity of the Ancient Sun Based on Noble Gas Studies of Etched Kapoeta Mineral Separates
M. N. Rao, D. H. Garrison, D. D. Bogard, A. V. Murali, D. C. Black
  1505

Composition of Solar Flare Argon Deduced from Kapoeta Etched Mineral Separates
M. N. Rao, D. H. Garrison, D. D. Bogard, A. V. Murali, D. C. Black
  1506

Characterization of Soil Components from the 79001/2 Core
M. N. Rao, D. S. McKay, D. H. Garrison, S. J. Wentworth, D. D. Bogard
  1507

Megaregolith Insulation and the Duration of Cooling to Isotopic Closure Within Differentiated Asteroids and the Moon
K. L. Rasmussen, H. Haack, P. H. Warren
  1508

Cosmogenic-Radionuclide Production Rates in Mini-Spherules
R. C. Reedy
  1509

Solar-Alpha-Particle Production of Nickel-59 in the Moon
R. C. Reedy
  1510

Fracture Density Statistics Along Radial Traverses Through the Crystalline Basement of the Vredefort Dome, South Africa--New Data from a NNW-Traverse
W. U. Reimold, R. J. Hart, M. A. G. Andreoli
  1511

Search for Dynamic Deformation Effects in Contact Breccias from South African Kimberlite Pipes
W. U. Reimold, T. McGee, G. Graup
  1512

Observations on Granitic Clasts in Granphyre from the Vredefort Dome, South Africa
W. U. Reimold, A. M. Reid, A. M. Therriault
  1513

Mid-Infrared Spectra of Komatiite vs. Basalt
D. P. Reyes, P. R. Christensen
  1514

Turbostratic Carbon with Remnant Precursor Material in Individual Chondritic Porous Interplanetary Dust Particles
F. J. M. Rietmeijer
  1515

Scanning Electron Microscope Analyses of Forsterite Powders Shocked at 14.8 51.4 and 78.8 GPa
F. J. M. Rietmeijer, A. Albrecht
  1516

Analytical Electron Microscope Analyses of Refractory Circumstellar, Interstellar and Interplanetary Dust Analogs
F. J. M. Rietmeijer, J. A. Nuth
  1517

Lakshmi Planum Volcanism: Basal Melting of Thickened Crust?
K. M. Roberts, J. W. Head
  1518

Models for the Origin of Lakshmi Planum, Venus
K. M. Roberts, J. W. Head
  1519

Discovery of Non-Contaminated Unmelted Cosmic Particles in Antarctica and Northern Canada Territories
E. Robin, C. Jehanno, R. M. Koerner, J. Pilon, R. Rocchia
  1520

The Highland-Lowland Boundary Formed on Mars Between the Late Noachian and the Early Hesperian
C. A. Robinson
  1521

Precise Topographic Measurements of Apollinaris and Tyrrhena Patera, Mars
M. S. Robinson
  1522

Saratov Meteorite: Grain Size Study
O. D. Rode
  1523

The Boundary of an Ancient Depression as Indicated by Crater Statistics
Zh. F. Rodionova, V. V. Shevchenko
  1524

Dependence on the Density of Lunar Crater Distribution on Relief
Zh. F. Rodionova, V. V. Shevchenko, P. M. Zazulyak, V. E. Zinger
  1525

Polycyclic Aromatic Hydrocarbons via Multicenter Reactions Induced by Solar Radiation
K. Roessler, G. Eich, A. Patnaik, E. Zddor
  1526

Chromium Isotopes in C Chondrites: Isotopic Heterogeneity and Further Evidence for Extinct 53Mn
M. Rotaru, J. L. Birck, C. J. Allegre
  1527

Collapsed "Lava" Tubes on Ariel?
D. A. Rothery
  1528

Estimates of Absolute Flux and Radiance Factor of Localized Regions on Mars in the 2-4 micron Wavelength Region
T. L. Roush, R. B. Singer
  1529

Derivation of Mid-Infrared (5-25 microns) Optical Constants of Some Silicates and Palagonite
T. L. Roush, J. Pollack, J. Orenberg
  1530

A Unique Carbonaceous Chondrite: Lewis Cliff 85332
A. E. Rubin, G. W. Kallemeyn
  1531

Sinuous Ridges of the South Polar Region, Mars: Possible Origins
S. W. Ruff, R. Greeley
  1532

On the Existence of Occluded Isotopically Light Carbon in Allende?
S. S. Russell, R. D. Ash, C. T. Pillinger, J. W. Arden
  1533

Nitrogen Concentration of Interstellar Diamond
S. S. Russell, C. T. Pillinger, J. W. Arden
  1534

Chondrule Formation in the Accretional Shock
T. V. Ruzmaikina
  1535

Impact Experiments: Catastrophic Fragmentation of Aggregate Targets
E. V. Ryan, D. R. Davis, W. K. Hartmann
  1536

Origin of a 6 MM Glass Sphere from the Apennine Front: Debris in the Rind
G. Ryder
  1537

On Application of SAR-Method for the Geological Nature of Mars Exploration
O. N. Rzhiga, A. S. Selivanov
  1538

Occurrence of Zircon in Magnesian Non-Cumulate Eucrite Yamato 791438
K. Saiki, H. Takeda, K. Toyoda, T. Tagai
  1539

Information of Elemental Distributions in Heavily Shocked Ureilites as a Guide to Deduce the Ureilite Formation Process
J. Saito, H. Takeda
  1540

Geochemistry of the Base of the Main Anorthosite-Bearing Series Stillwater Complex
P. A. Salpas, K. D. Pass
  1541

Heating of an Accreting Protoplanet by Blanketing Effect of a Primary Solar-Composition Atmosphere
S. Sasaki
  1542

Origin of Phobos--Aerodynamic Drag Capture by the Primary Atmosphere of Mars
S. Sasaki
  1543

Magellan Venus Radar Mapping Mission: Geologic Questions for the First Weeks of Operations
R. S. Saunders, E. R. Stofan
  1544

Peculiarities of Cation Diffusion in Shock Plagioclase Melts (Popigal Astrobleme, USSR)
L. V. Sazonova
  1545

New USGS Open-File Geomorphic/Geologic and Tectonic Maps of the Northern Quarter of Venus
G. G. Schaber, R. C. Kozak
  1546

Chemical Evolution of the Early Martian Hydrosphere
M. W. Schaefer
  1547

Central Pit Formation in Craters on Icy Satellites
P. M. Schenk
  1548

Crater Morphology and Modification on Ganymede, Callisto, and Tethys
P. M. Schenk
  1549

Crater Simulations in Subscale Jointed Rock: Preliminary Results
R. M. Schmidt
  1550

A General Theory of Mass Extinctions in the Phanerozoic, I. Observations and Constraints
R. A. Schmitt
  1551

A General Theory of Mass Extinctions in the Phanerozoic, II. A Brief Outline
R. A. Schmitt
  1552

Reducing Conditions in the Pacific Ocean Before, At, and After the K/T (Cretaceous/Tertiary) Boundary, III
R. A. Schmitt
  1553

Global Relationships Between Volcanic Vents and Fractures Radial to Large Impact Basins on Mars
B. D. Schneid, R. Greeley
  1554

Iron-Nickel Sulfides in Interplanetary Dust
L. S. Schramm, D. E. Brownlee
  1555

Atmospheric Effects on Cratering Efficiency
P. H. Schultz
  1556

Evidence for Atmospheric Effects on Martian Crater Shape
P. H. Schultz
  1557

Decapitated Impactors in the Laboratory and on the Planets
P. H. Schultz, D. E. Gault
  1558

Impact Generation of Orbiting Debris Around Mars
P. H. Schultz, D. A. Crawford, D. E. Gault
  1559

Complex Early Rifting in Valles Marineris: Results from Preliminary Geologic Mapping of the Ophir Planum Region of Mars, 1:500,000 Scale
R. A. Schultz
  1560

Origin of the Echelon Geometries of Joints and Faults on Planetary Surfaces
R. A. Schultz
  1561

Possible Deficiency of Large Martian Craters and Relative Cratering of the Terrestrial Planets
R. A. Schultz
  1562

Strike-Slip Faulting, Wrinkle Ridges, and Time Variable Stress States in the Coprates Region of Mars
R. A. Schultz
  1563

Geology, Structure, and Statistics of Multi-Ring Basins on Mars
R. A. Schultz, H. V. Frey
  1564

An Evaluation of the Reliability and Usefulness of Microprobe Fused Bead Analyses for Petrogenetic Interpretations
B. C. Schuraytz, G. Ryder
  1565

Evidence for Multiple Flooding Episodes in Kasei Valles, Mars
D. H. Scott, J. M. Dohm
  1566

Mottled Terrain: A Continuing Martian Enigma
D. H. Scott, J. R. Underwood
  1567

Origins of Pallasites at the Core-Mantle Boundaries of Asteroids
E. R. D. Scott, G. J. Taylor
  1568

The Natural TL Survey of the 1987/1988 Antarctic Meteorite Collections: Pairing, an Unusual Carbonaceous Chondrite Group and the Lunar Meteorites
D. W. G. Sears, H. Sears, B. M. Myers
  1569

Projectile Dissemination and Fractionation at Wabar Crater, Saudi Arabia
T. H. See, D. W. Mittlefehldt, F. Hoerz, J. Wasson
  1570

Thermoscanning of the Mars Surface
A. Selivanov, M. Naraeva
  1571

Olivine-Hypersthene Chondrite in the Luna 16 Soil
A. S. Semenova, N. N. Kononkova, E. V. Guseva
  1572

Geology and Structure of Beta Regio: Results from New Arecibo Data
D. A. Senske, J. W. Head, E. R. Stofan, D. B. Campbell
  1573

La/Sm Ratios in Mare Basalts as a Consequence of Mafic Cumulate Fractionation from an Initial Lunar Magma
E. E. Shaffer, J. G. Brophy, A. Basu
  1574

The Relation of the Lava Complexes of the Olympus Mons on Mars
I. V. Shalimov
  1575

Distribution According to the Size of Volcanic Ring Structures in the North of Venus
I. V. Shalimov, A. M. Nikishin
  1576

The Marquez Dome Impact Structure, Leon County, Texas
V. L. Sharpton, J. W. Gibson Jr.
  1577

MG Isotope Heterogeneity in Plagioclase Olivine Inclusions
Y. J. Sheng, I. D. Hutcheon, G. J. Wasserburg
  1578

The Western Highland Province at the Apollo 14 Site
J. W. Shervais
  1579

Lunar Mare Volcanism: Mixing of Distinct, Mantle Source Regions with KREEP-like Component
J. W. Shervais, S. K. Vetter
  1580

A Possible Lunar Science Objective for Galileo
V. V. Shevchenko
  1581

Sm-Nd Age of a Pristine Norite Clast from Breccia 15445
C.-Y. Shih, B. M. Bansal, H. Wiesmann, E. J. Dasch, L. E. Nyquist, D. D. Bogard
  1582

Rb-Sr and Sm-Nd Isotopic Studies of an Apollo 17 KREEPy Basalt
C.-Y. Shih, B. M. Bansal, H. Wiesmann, L. E. Nyquist
  1583

Implications of the Reported Amino Acid Concentrations in the Murchison Meteorite
E. L. Shock, M. D. Schulte
  1584

Survey for Bright Trojan Asteroids
C. S. Shoemaker, E. M. Shoemaker
  1585

Earth-Crossing Asteroids, 1989
E. M. Shoemaker, C. S. Shoemaker, R. F. Wolfe, H. E. Holt
  1586

Compositionally Zoned Fassaite in an Allende Coarse-grained Inclusion
S. B. Simon, L. Grossman
  1587

Comparative Petrology of Lunar Regolith Breccias and Soils, and Implications for the Howardite Parent Body Regolith
S. B. Simon, J. J. Papike
  1588

"Relict" Fassaite in Type B1 CAI's: Products of Late-Stage Liquids?
S. B. Simon, A. M. Davis, L. Grossman
  1589

Two-Dimensional Position-Sensing PVDF Dust Detector for Measurement of Dust Particle Trajectory
J. A. Simpson, A. J. Tuzzolino
  1590

Visible and Near-IR Spectral Imaging of Mars During the 1988 Opposition
R. B. Singer, J. S. Miller, K. W. Wells, E. S. Bus
  1591

Bipolar Outflows and a New Model of the Early Solar System. Part I: Overview and Implications of the Model
W. R. Skinner
  1592

Bipolar Outflows and a New Model of the Early Solar System. Part II: The Origins of Chondrules, Isotopic Anomalies, and Chemical Fractionations
W. R. Skinner
  1593

Akkruva-Allat Volcanic Belt on Venus
E. N. Slyuta
  1594

Large Shield Volcanoes ( > 100 KM in Diameter) on Venus: Morphologic Types
E. N. Slyuta
  1595

Intermediate (20-100 KM ) Sized Volcanic Edifices on Venus
E. N. Slyuta, M. A. Kreslavsky
  1596

Geoid to Topography Ratios for 14 Venusian Features: Implications for Compensation Mechanisms
S. E. Smrekar, R. J. Phillips
  1597

Issues in Venus Tectonics: Retrospect and Prospect
S. C. Solomon
  1598

TEPEV Mons and the Elastic Lithosphere of Venus: an Assessment of Flexure Models
S. C. Solomon, J. W. Head
  1599

Disk-resolved Ground Based Infrared Imaging of Io
J. R. Spencer, M. A. Shure, M. E. Ressler, D. Toomey, A. Denault, W. M. Sinton, J. D. Goguen
  1600

Siderophile Elements in the Primitive Upper Mantle
B. Spettel, H. Palme, H. Waenke
  1601

Comparison of Tessera Grabens on Venus and Grabens of Baikal Region and Basin and Range Province on Earth
V. V. Spiricheva, A. M. Nikishin
  1602

Clasts in Lunar Impact Melts and the Origin of Low-K Fra Mauro Basalt
P. D. Spudis, G. J. Taylor, K. A. McCormick, G. Ryder, K. Keil, R. A. F. Grieve
  1603

Stratospheric Dust Collection: an Isotopic Survey of Terrestrial and Cosmic Particles
F. J. Stadermann, R. M. Walker, E. Zinner
  1604

Radiation-induced Formation of Polycyclic Aromatic Hydrocarbons (PAH's) on Graphite Surface: Implication for Cosmic Dust and Bodies
L. V. Starukhina, Yu. G. Shkuratov, L. A. Kodina, A. I. Ogloblina, N. P. Stankevich, T. I. Peregon, L. P. Tishchenko
  1605

Crystal Structure of Yoshiokaite Based on Synthetic Sample--Relation to Nepheline
I. M. Steele
  1606

Micro-Textural and -Chemical Features of Isolated Forsterites of C3 Meteorites with Implications for Origin
I. M. Steele
  1607

Dry Carbonate Formation on Mars: A Plausible Sink for an Early Dense CO2 Atmosphere?
S. K. Stephens, D. J. Stevenson
  1608

Why Existing Terrestrial Planet Thermal History Calculations Should Not Be Believed (and What To Do About It)
D. J. Stevenson, S. S. Bittker
  1609

Puzzles of Triton
D. J. Stevenson, A. S. Gandhi
  1610

The Isotopic Signature of Hydrogen in Lunar Basalts: Spallogenic or Primordial?
M. Stievenard, J. Jouzel, F. Robert
  1611

Coronae on Venus: Predictions for Magellan
E. R. Stofan
  1612

Beta-Eisila Deformation Zone: Analysis from Recent Arecibo Images
E. R. Stofan, J. W. Head, D. B. Campbell
  1613

THEMIS Regio, Venus: Analysis from High Resolution Arecibo Images
E. R. Stofan, J. W. Head, D. B. Campbell
  1614

SI Isotopes in SiC from Carbonaceous and Enstatite Chondrites
J. Stone, I. D. Hutcheon, S. Epstein, G. J. Wasserburg
  1615

Ferrolysis of Iron-bearing Martian Brines: Origin of Dust-Storm Particulates on Mars
D. W. Straub, R. G. Burns
  1616

Oxidized Pyroxenes and Degradation of Their Visible-Near Infrared Spectra: Implications to Remote-Sensing of Mars
D. W. Straub, R. G. Burns
  1617

The Cratering Record on Triton
R. G. Strom, S. K. Croft, J. M. Boyce
  1618

Nitrogen Components and Isotopic Signatures in the Acapulco Meteorite
G. Sturgeon, K. Marti
  1619

Heavy Nitrogen in Y74191 (L3) Chondrite
N. Sugiura, K. Hashizume
  1620

Extraction of Compositional Information from Olivine Reflectance Spectra: A New Capability for Lunar Exploration
J. M. Sunshine, C. M. Pieters
  1621

Trace Element Compositions and Mineralogy of Low-Nickel Stratospheric Particles
S. R. Sutton, J. P. Bradley, G. J. Flynn
  1622

Noble Gases in the Amorphous Carbon 6 Synthesized by Glow-Discharge CVD
K. Suzuki, J. Matsuda
  1623

Searching for Crisium Basin Ejecta: Chemistry and Ages of Luna 20m Impact Melts
T. D. Swindle, P. D. Spudis, G. J. Taylor, R. Korotev, R. H. Nichols, C. T. Olinger
  1624

Chemical Compositions of Leoville and Vigarano Inclusions
P. J. Sylvester, L. Grossman, G. J. MacPherson
  1625

Mineralogical Comparisons of Two Large Lunar Meteorites MAC88105 and Y86032
H. Takeda, J. Saito, H. Mori, O. Tachikawa, M. Miyamoto
  1626

Lunar-Outpost Astronomy: A Scenario for Paced, High-Return Growth
D. L. Talent, H. J. Smith, F. Vilas
  1627

Martian Geologic "Revolutions". A Tale of Two pricesses
K. L. Tanaka
  1628

Hypervelocity Impact Studies Conducted to Analyze the Dynamics of Fragmentation and Dispersion of Micron-sized Fragments of an Imterplanetary Dust Particle Analog
W. G. Tanner, R. A. McDonald, W. M. Alexander, F. Hoerz
  1629

Lunar Meteorite MacAlpine Hills 88105 and the Bombardment History of the Moon
G. J. Taylor
  1630

Magnetic Benefication of Highlands Soils: Concentrations of Anorthite and Agglutinates
L. A. Taylor, R. R. Oder
  1631

Magnetic Benefication of Hi-Ti Mare Soils: Concentrations of Ilmenite and Other Components
L. A. Taylor, R. R. Oder
  1632

Recent Results of the Comet Simulation Project (KOSI): Implications for the Dust Components of Comets
K. Thiel, G. Kolzer, H. Kochan, E. Grun, H. Kohl
  1633

Excess 33S and 36S in Iron Meteorites
M. H. Thiemens, X. Gao
  1634

Mineralogical Descriptions of Eight Hydrated Interplanetary Dust Particles and Their Relationship to Chondrite Matrix
K. L. Thomas, M. E. Zolensky, W. Kloeck, D. S. McKay
  1635

A Radar-Echo Model for Mars
T. W. Thompson, H. J. Moore
  1636

The Ultramafic Series -Banded Series Contact in the Stillwater Complex: Evidence for Thermal Erosion
M. W. Thurber, I. S. McCallum
  1637

Matrix Compositions and Mineralogy of the Alais and Ivuna CI Carbonaceous Chondrites
K. Tomeoka
  1638

X-Ray Micro-Analysis of Micro-Inclusions in a Zaire Coated Diamond
K. Tomeoka, M. Ozima, S. Zashu, S. Sato, S. Yazu
  1639

The Fate of Ejected Mercury Mantle Material from a Giant Impact
W. B. Tonks, H. J. Melosh, W. B. McKinnon
  1640

Crystallization of Angrites, CAIS and Ca-Al Chondrules: Fassaite-Spinel Liquidi in CMAST
A. H. Treiman
  1641

Intact Capture of Cosmic Dust Analogs in Aerogel
P. Tsou, J. P. Bradley, D. E. Brownlee, H. Fechitg, F. L. Hrubesh, P. W. Keaton, M. Laurance, C. G. Simon, G. L. Stradling, A. Teetsov, A. L. Albee
  1642

Implications of Crustal Formation on Mars from Parameterized Convection Calculations
D. L. Turcotte, J. Huang
  1643

Phase Equilibria Constraints on Archean Crustal Genesis from Crystallization Experiments on Trondhjemite with Water at 10-17 kbar
S. R. V. D. Lann, A. D. Johnson, P. J. Wyllie
  1644

Interaction Between Ejecta Vapor Plumes and Atmospheres, with Application to the KT Extinctions
A. M. Vickery
  1645

CCD Reflectance Spectra of Selected Asteroids
F. Vilas, L. A. McFadden
  1646

Cosmogenic Radionuclides in three Lunar Meteorites from Antarctica: Yamato 86032 MacAlpine Hills 88104 and MacAlpine Hills 88105
S. Vogt, G. F. Herzog, D. Fink, J. Klein, R. Middleton
  1647

Zinc Isotope Anomalies and Neutron-rich Statistical Equilibrium Synthesis
J. Volkening, D. A. Papanastassiou
  1648

A Model for the Shape of Overthrust Zones on Venus
R. W. Vorder Bruegge, R. C. Fletcher
  1649

Formation of Eastern Ishtar Terra, Venus: A Comparison of Models
R. W. Vorder Bruegge, J. W. Head
  1650

Formation of Eastern Ishtar Terra, Venus, Though Accretion of Crustal Terranes
R. W. Vorder Bruegge, J. W. Head
  1651

Radiometric Calibration of the Magellan Radar
S. D. Wall, T. K. Johnson
  1652

Labile Trace Elements in Angrites
M.-S. Wang, M. E. Lipschutz
  1653

Labile Trace Elements in Lunar Meteorite MAC 88105
M.-S. Wang, M. E. Lipschutz
  1654

Lunar Siderophiles
H. Waenke, G. Dreibus, H. Palme
  1655

Did Mars Pass Through a Secular Spin-Orbit Resonance?
W. R. Ward, D. J. Rudy
  1656

OLivine-Porphyritic Vitrophyre 12024,15: A Sample of the Margin of a Lunar Lava Flow
P. H. Warren, E. A. Jerde
  1657

Geochemistry of the LEW87051 Angrite and Other Basaltic Achondrites
P. H. Warren, G. W. Kallemeyn
  1658

Compositional-Petrographic Investigation of Two Newly-Acquired Moon Rocks
P. H. Warren, G. W. Kallemeyn, E. A. Jerde
  1659

Magnetic Record in Primitive Materials
P. J. Wasilewski, J. Nuth
  1660

Bimodal IR Distribution in the Canyon Diablo Meteoroid
J. T. Wasson
  1661

Collision and Tidal Interaction Between Planetesimals
S. Watanabe, S. M. Miyama
  1662

The Nature and Origin of Periodically Spaced Wrinkle Ridges on Mars
T. R. Watters
  1663

Domains of Regional Pure Shear on the Terrestrial Planets
T. R. Watters, M. J. Tuttle
  1664

Origin of Curvilinear Graben in Southwest Lunae Planum, Mars
T. R. Watters, M. J. Tuttle
  1665

Distribution of Strain in the Floor of the Olympus Mons Caldera
T. R. Watters, D. J. Chadwick, M. C. Liu
  1666

Symmetry of Inferred Stress Fields in the Tharsis Region of Mars
T. R. Watters, M. J. Tuttle, F. J. Kiger
  1667

Simulants for Martian Surface Minerals
P. W. Weiblen
  1668

Refractory-rich Inclusions in CR2 (Renazzo-type) Chondrites
M. K. Weisberg, M. Prinz
  1669

Thermal Infrared Remote Sensing of Modification Processes at Cima Volcanic Field, California
C. M. Weitz, T. G. Farr
  1670

A New Isotope Effect and its Possible Importance in Meteoritics
J. Wen, M. H. Thiemens
  1671

Pre-Terrestrial Origin of "Rust" in the Nakhla Meteorite
S. J. Wentworth, J. L. Gooding
  1672

Lunar Meteorite MAC88104/5: Petrography and Glass Compositions
S. J. Wentworth, D. S. McKay
  1673

Runway Planetesimal Growth: Agreement Between Analytical Solution of the Coagulation Equation and the Results of Numerical Physical Modelling
G. W. Wetherill
  1674

An Ion Microprobe Study of REE Distributions in Sulfide and Silicate Minerals in the Norton County Aubrite
M. M. Wheelock, C. F. Heavilon, K. Keil
  1675

The Early Siliceous component of Planetary Crusts: Experimental Petrology of the Tonalite-Trondhjemite Rock Series
B. S. White, S. van der Laan, P. J. Wyllie
  1676

A Model for Crustal Subduction by Large Impacts
R. W. Wichman, P. H. Schultz
  1677

Large Scale Compression Structures in the Eridania-Phaethontis Region: More Evidence for Polar Wandering
R. W. Wichman, P. H. Schultz
  1678

Noble Gas, 26Al, 10Be, and 14C Concentrations and Track Densities of Bur Gheluai: Evidence for a Two-Stage Exposure History
R. Wieler, P. Signer, A. J. T. Jull, P. Pellas, C. Tuniz, A. Maras, D. Fink, J. Klein, R. Middleton, G. F. Herzog, S. Vogt
  1679

A Tectonic Model for Tellus Regio, Venus, Based on Stress Analysis and Comparison with Venera 15/16 Radar Images
D. R. Williams, R. Greeley
  1680

Possible Aeolian Megaripples on Mars
S. H. Williams
  1681

Preliminary Geologic Mapping Near the Nilosyrtis Mensae, Mars
S. H. Williams, J. R. Zimbelman
  1682

Factors Controlling the Structures of Magma Chambers in Basaltic Volcanoes
L. Wilson, J. W. Head
  1683

Widths of Dikes on Earth and Mars
L. Wilson, E. A. Parfitt
  1684

Lava Flow Morphologies and Eruption Conditions on Venus
L. Wilson, J. W. Head, D. B. Campbell
  1685

Proposed New Asteroid Families
R. F. Wolfe
  1686

Meridional Symmetry of the Venus Polar Complex
C. A. Wood, C. R. Coombs
  1687

A Search for Carbonate Minerals in Chassigny
I. P. Wright, M. M. Grady, C. T. Pillinger
  1688

Volumetric Distributions of Mars Topography
S. S. C. Wu, A. E. Howington-Kraus
  1689

Topographic Mapping of PHOBOS
S. S. C. Wu, F. J. Schafer, R. Jordan
  1690

Diamond Synthesis by Shock Transformation and Noble Gas Studies
H. Yajima, J. Matsuda, Y. Syono, K. Kusaba
  1691

Efficiency of Angular Momentum Transfer in Low Velocity Oblique Impacts
M. Yanagisawa, J. Eluszkiewicz, T. J. Ahrens
  1692

Anorthositic Gabbro: Cumulate Meteorite from Antarctica
K. Yanai
  1693

Carbon Isotope Fractionation in Fischer-Tropsch Type Reactions
G. U. Yuen, J. A. Pecore, J. K. Kerridge, T. J. Pinnavaia, E. G. Rightor, J. Flores, K. Wedeking, R. Mariner, D. J. Des Marais, S. Chang
  1694

The Divnoe Meteorite I. Petrology and Mineralogy
N. I. Zaslavskaya, M. I. Petaev
  1695

The Divnoe Meteorite II. Mineral Chemistry
N. I. Zaslavskaya, M. I. Petaev, N. N. Kononkova, G. M. Kolesov
  1696

Geologic Mapping of the Central Mangala Valles Region, Mars
J. R. Zimbelman
  1697

Henry Crater, Mars: Thick, Layered Deposit Preserved on a Crater Floor in the Martian Highlands
J. R. Zimbelman
  1698

An Evaluation of the Possible Extent of Bedrock Exposure in the Sinus Meridiani Region of the Martian Highlands
J. R. Zimbelman, R. A. Craddock
  1699

Interstellar Graphite and Other Carbonaceous Grains from the Murchison Meteorite: Structure, Composition and Isotopes of C, N, and NE
E. Zinner, B. Wopenka, S. Amari, E. Anders
  1700

Cosmic Dust Capture Simulation Experiments Using Silica Aerogels
M. E. Zolensky, R. A. Barrett, L. Hrubesh, F. Hoerz, D. Lindstrom
  1701

The Mineralogy of Matrix and Chondrule Rims in CM Chondrites
M. E. Zolensky, R. A. Barrett, W. Kloeck, J. L. Gooding
  1702

Flux VS Direction of Impacts on LDEF by Meteoroids and Orbital Debris
H. A. Zook
  1703

Constraints on the Depth and Geometry of the Magma Chamber of the Olympus Mons Volcano, Mars
M. T. Zuber, P. J. Mouginis-Mark
  1704