Seventeenth Lunar and Planetary Science Conference

TABLE OF CONTENTS

no.

Lunar Sourced Inorganic Composites for Space Construction
W. N. Agosto 		  1001

Spectral Properties of Selected Soils from the Dry Valleys of Antarctica
D. G. Agresti, R. V. Morris, J. A. Newcomb, H. V. Lauer 		  1002

Evidence for Superparamagnetism in the Orgueil and Tieschitz Meteorites
D. G. Agresti, M. A. Qasem, T. J. Wdowiak 		  1003

Mars: Volcanic Plains in the Cratered Uplands and Possible Tectonic Associations
E. F. Albin, R. Greeley 		  1004

Cretaceous/tertiary Event: Iridium Distribution in Turkmenia Sections
A. S. Alekseev, L. D. Barsukova, G. M. Kolesov, M. A. Nazarov, K. N. Amanniyazov 		  1005

Shock Wave Experiments on Iron Sulfide and Sulfur in Planetary Cores
W. W. Anderson, T. J. Ahrens 		  1006

Zelda's Neighborhood: Xenophagia of an Equilibrated Fremdling by Spinel
J. T. Armstrong, I. D. Hutcheon, G. J. Wasserburg 		  1007

Cooling History of Apollo 17 Orange and Black Glasses: Implications for Their Formation
J. Arndt, W. V. Engelhardt 		  1008

On the Rate of Formation of Sedimentary Debris on Mars
R. E. Arvidson 		  1009

Shocked Quartz Grains from K/t Boundary Sediments
D. D. Badjukov, M. A. Nazarov, I. V. Suponeva 		  1010

Mass Independent Oxygen Isotopic Fractionation in the Microwave Region
S. K. Bains, M. H. Thiemens 		  1011

Lithospheric Modelling of Venus
W. B. Banerdt, M. P. Golombek 		  1012

Relative Ages of Martian Terrain Units
N. G. Barlow, R. G. Strom 		  1013

Impact Features and Projectile Flux on Returned Solar Max Material
R. A. Barrett, H. A. Zook, J. L. Warren, L. S. Schramm, D. S. McKay 		  1014

Mineral Composition of Venus' Soil at Venera 13, Venera 14, and VEGA 2 Landing Sites: Thermodynamic Prediction
V. L. Barsukov, S. P. Borunov, V. P. Volkov, M. Yu. Zolotov, Yu. I. Sidorov, I. L. Khodakovsky 		  1015

Mineral Compositions and Assemblages in Chondrules of Different Mineralogical-Structural Types of the Allende CV Carbonaceous Chondrite
G. V. Baryshnikova, S. A. Stakheeva, K. I. Ignatenko, A. K. Lavrukhina 		  1016

A Probabilistic Approach to Ballistic Differentiation of Surfacial Soils on Moon-Like Planets
A. Basu, R. N. Bhattacharya 		  1017

Digital Image Models of Planetary Surfaces
R. M. Batson 		  1018

Oxygen Fugacities in the Solar Nebula during Crystallization of Fassaite in Allende Inclusions
J. R. Beckett, L. Grossman 		  1019

IRAS Asteroid and Comet Ground-Based Data File
D. F. Bender, E. F. Tedesco 		  1020

The Origin of the Moon: 3d Numerical Simulations of a Giant Impact
W. Benz, W. L. Slattery, A. G. W. Cameron 		  1021

40AR-39AR Ages of Apollo 16 North Ray Crater Rocks and Dimict Breccias
T. J. Bernatowicz, M. M. Lindstrom, F. A. Podosek 		  1022

Diversity of Parent Magmas of Pristine Lunar Rocks
M. G. Bersch, G. J. Taylor, K. Keil 		  1023

Partial Melting of a Martian Mantle
C. Bertka, J. R. Holloway 		  1024

Mars: Gravity, Topography and Dynamic Compensation
B. G. Bills, M. A. Richards, W. S. Kiefer 		  1025

Characterization of Venera 15/16 Units Using Pioneer Venus Reflectivity and RMS Slope
D. L. Bindschadler, J. W. Head 		  1026

VEGA Landing Sites: Venera 15/16 Unit Analogs from Pioneer Venus Reflectivity and RMS Slope
D. L. Bindschadler, J. W. Head, J. B. Garvin 		  1027

Oxidation of Refractory Metal-Rich Assemblages at High Temperatures
A. Bischoff, H. Palme 		  1028

Extraterrestrial Olivines Brought Back from Space
G. E. Blanford, F. J. M. Rietmeijer, L. S. Schramm, D. S. McKay 		  1029

Cone Crater Consortium, Apollo 14: (1) Identification and Frequency Distribution of Rock Types in the Crater Basement
K. Bobe, S. Lingner, D. Stoffler 		  1030

Interactive Processing of Venus Images
I. Bockstein, P. Chochia, M. Kronrod 		  1031

Does Venus' Atmosphere Contain a Terrestrial-Like Component?
D. Bogard 		  1032

Noble Gases Implanted by Artificial Shock: Implications for Trapped Martian Gases in the EETA79001 Meteorite
D. D. Bogard, F. Horz, P. Johnson, R. Schmidt 		  1033

The Lunar Endogenic "monomineralic" Glasses
O. A. Bogatikov, N. A. Ashikhmina, D. I. Frikh-Khar 		  1034

Worldwide Size Distribution of Shocked Quartz at the K/t Boundary: Evidence for a North American Impact Site
B. F. Bohor, G. A. Izett 		  1035

Magnetic Properties of Shocked and Thermally Altered Nontronite
M. B. Boslough, E. L. Venturini, R. A. Graham 		  1036

Composition of Apatite and Biotite from the Stillwater and Bushveld Complexes. Part II
A. E. Boudreau, E. A. Mathez, I. S. McCallum 		  1037

The Aeolian Environment on Venus
S. Bougan, R. Greeley, J. Marshall 		  1038

Cosmic-Ray Tracks Versus 60CO: a Strong Discrepancy in Shielding Depths
M. Bourot-Denise, P. Pellas, C. Perron 		  1039

Trace Elements in Efremovka Fine-Grained Inclusion E14: Evidence for High Temperature, Oxidizing Fractionations in the Solar Nebula
W. V. Boynton, D. A. Wark, A. A. Ulyanov 		  1040

Solar Max Impact Particles: Perturbation of Captured Material
J. Bradley, W. Carey, R. M. Walker 		  1041

Small Valley Networks and the Past and Present Distribution of Subsurface Volatiles, Aeolis Quadrangle, Mars
G. R. Brakenridge 		  1042

The Effect of Preoxidation on the Rate and Extent of Reduction of Ilmenite
R. A. Briggs, A. Sacco 		  1043

Evidence for 26AL and MG Isotopic Heterogeneity in a Fine-Grained CAI
C. A. Brigham, I. D. Hutcheon, D. A. Papanastassiou, G. J. Wasserburg 		  1044

Multispectral Interpretation of Geologic Materials Exposed at the Viking Lander Sites
E. A. Bruckenthal, R. B. Singer, E. A. Guinness, R. E. Arvidson 		  1045

Allende: Profile of Parent Body Growth
T. E. Bunch, S. Chang, P. Cassen, R. Reynolds 		  1046

Ferric Hydrolysates on Mars: Basic Fe(iii) Sulfates
R. G. Burns 		  1047

Hisingerite and Iddingsite: Deuteric Alteration Products of Basalts on Mars
R. G. Burns 		  1048

The Hydrogen Content of Lunar Soils
R. Bustin, R. H. Carr, E. K. Gibson, M. A. Sommer 		  1049

Conformity as Measured by a Straight - Petrological Shibboleth Set Straight
J. C. Butler 		  1050

Pre-Compaction Irradiation of Meteorite Grains
M. W. Caffee, J. N. Goswami, C. M. Hohenberg, T. D. Swindle 		  1051

Density and Composition of the Mercury Mantle after Evaporative Mass Loss
A. G. W. Cameron, B. Fegley 		  1052

Gas Chromatographic Instrumentation for the Analysis of Aerosols and Gases in Titan's Atmosphere
G. C. Carle, D. R. Kojiro, B. J. O'Hara, T. W. Scattergood, J. R. Valentin 		  1053

Effusion Rates of High-Volume Lavas, Alba Patera, Mars
P. Cattermole 		  1054

High Volume Volcanic Flows at Alba Patera, Mars
P. Cattermole 		  1055

Linear Volcanic Features at Alba Patera, Mars
P. Cattermole 		  1056

Monte Carlo Simulation of Trapped Liquid Density: Implications for the Compaction of Igneous Cumulates
C. I. Chalokwu 		  1057

S (not Equal To) N (maybe Equal) C
J. H. Chen, G. J. Wasserburg 		  1058

Synchrotron X-Ray Fluorescence Analysis of ni, cu, zn, ga, ge, se, and Pb(as) in Unpolished Cosmic Spherules
P. Chevallier, C. Jehano, M. Maurette, S. Sutton, J. Wang 		  1059

Further Aspects of Lunar Palaeointensity Determinations and the Origin of the Ancient Lunar Magnetic Field
S. K. Chowdhary, S. K. Runcorn, D. W. Collinson, A. Stephenson 		  1060

New Molecular Species Ejected from Residues of Irradiated Volatiles: Implications for Comets
D. Chrisey, J. W. Boring, R. E. Johnson, W. L. Brown, L. J. Lanzerotti, G. Foti 		  1061

Charged-Particle Alteration of Volatiles on Outer Solar System Bodies
D. Chrisey, J. Phipps, J. W. Boring, R. E. Johnson, L. I. Lanzerotti, W. L. Brown 		  1062

Seasonal Variability of Martian Surface Albedos: Implications for Dust Deposition and Removal
P. R. Christensen 		  1063

Seasonal and Diurnal Variability of Mars Water-Ice Clouds
P. R. Christensen, R. W. Zurek, L. L. Jaramillo 		  1064

Geomorphic Evidence for Subsurface Volatile Reservoirs in the Elysium Region of Mars
E. H. Christiansen, J. A. Hopler 		  1065

Spray: a Chondritic Interplanetary Dust Particle Containing Refractory Minerals
R. Christoffersen, P. R. Buseck 		  1066

FMR and Mossbauer Measurements of the Iron Distribution in the Luna 16, 20, and 24 Grain Size Fractions
A. Cimbalnikova, Z. Frait, O. D. Rode, T. Zemcik 		  1067

Impact Experiments on the NASA KC-135 Reduced-Gravity Aircraft: Early Results
M. J. Cintala, F. Horz, T. H. See 		  1068

Venus: Images of Rolling Hills Terrane from Tristatic S-Band Radar Observation
P. E. Clark, R. F. Jurgens, M. Kobrick 		  1069

Mercury: New Results from Dual Polarization Measurements at X-Band
P. E. Clark, R. F. Jurgens, T. W. Thompson, L. Robinett, F. Chan, S. Brokl, C. Franck, E. Stone 		  1070

Carbon Isotopes in Interstellar Aluminium
D. D. Clayton 		  1071

Oxygen, Silicon, and Magnesium Isotopes in Leoville Refractory Inclusions
R. N. Clayton, T. K. Mayeda, H. Palme, J. Laughlin 		  1072

Oxygen Isotope Confirmation of a Genetic Association Between Achondrites and IIIAB Iron Meteorites
R. N. Clayton, T. K. Mayeda, M. Prinz, C. E. Nehru, J. S. Delaney 		  1073

The Mars Thermal Model (marstherm): a FORTRAN 77 Finite-Difference Program Designed for General Distribution
S. M. Clifford, C. J. Bartels 		  1074

Predictive Thermodynamic Modeling for Trace Element Partitioning in Magmatic Systems
R. O. Colson, L. A. Taylor, G. A. McKay 		  1075

Preliminary Hypervelocity Impact Calibration of Solar Max Thermal Blankets and Louvers
B. Cour-Palais 		  1076

Thermal Models of Marginal Differentiation on Ganymede and Callisto
S. K. Croft 		  1077

Isotopic Provenance of Aluminous Mare Basalt from the Fra Mauro Formation
E. J. Dasch, C.-Y. Shih, B. M. Bansal, H. Wiesmann, L. E. Nyquist 		  1078

Eruption Pressures during Phase 23 OF the Pu'u 'o'o Eruption on Kilauea, Hawaii: Planetary Implications
A. G. Davies, L. Wilson 		  1079

Magnesium and Titanium Isotopic Compositions and Trace Element Chemistry of Refractory Inclusions in the Ornans Carbonaceous Chondrite
A. M. Davis, R. W. Hinton 		  1080

Experimental Studies of Catastrophic Disruption
D. R. Davis, S. J. Weidenschilling, E. V. Ryan, B. L. Williams 		  1081

Global Petrologic Variations on the Moon: a Ternary Diagram Approach
P. A. Davis, P. D. Spudis 		  1082

Cathodoluminescence of Type 3 Ordinary Chondrites
J. Dehart, D. W. G. Sears 		  1083

Ring Furrows of the Martian Highlands
R. A. de Hon, E. E. McDaniel 		  1084

Phase Equilibria for Basaltic Achondrites
J. S. Delaney 		  1085

The Basaltic Achondrite Planetoid
J. S. Delaney 		  1086

A New Aspect of Apollo 14 Regolith Breccias: Different Glass Populations and Their Potential for Charting Space/time Variations
J. W. Delano 		  1087

Chemical Variations among the Moldavite Tektites: Major-Element Data
J. W. Delano, V. Bouska, M. M. Fernandez 		  1088

Collaborative Study of the Apollo 15 Pristine Yellow/brown Glasses: an Interim Report
J. W. Delano, S. S. Hughes, R. A. Schmitt 		  1089

Warning to Lunar Glass Students: Possible Contamination from Colored Ovoids Produced by Gas Lighter-Misch Metal Flints
J. W. Delano, P. L. Verplanck, S. S. Hughes, R. A. Schmitt 		  1090

Rb-Sr Studies of Apollo 16 Impact Melt Rocks
A. Deutsch 		  1091

On the Age of Lunar Anorthosites
A. Deutsch, H. Palme, D. Stoffler 		  1092

The Isotopic Composition of Hydrogen in Some Carbonaceous Chondrites
A. L. Devirts, A. A. Ulyanov, A. V. Ivanov, E. P. Lagutina, Yu. A. Shukolyukov 		  1093

A Possible Origin for Chondrule-Like Particles in the 3.6-3.3 GA Barberton Greenstone Belt, South Africa
M. J. de Wit 		  1094

Platinoids in a 3.6 GA Nickel-Iron Occurrence: Implications for Early Terrestrial Evolution and Iridium Anomalies
M. J. de Wit, M. Tredoux, R. J. Hart, R. Armstrong, J. P. F. Sellschop 		  1095

Calculations of Martian Cosmic Ray Induced Neutron Spectra
D. M. Drake, W. C. Feldman, B. M. Jakosky 		  1096

Site Selection for a Lunar Base; Science Considerations
M. B. Duke, D. S. McKay, W. W. Mendell 		  1097

The Oxygen Isotope Geochemistry of the Stillwater Complex
J. T. Dunn, I. S. McCallum 		  1098

Can Cratering Periodicities BE Produced AD Lib?
R. J. Durrheim, W. U. Reimold 		  1099

The Effects of Composition, Oxygen Fugacity, and Crystal Structure on the Color of Hibonite
M. D. Dyar, T. C. Solberg, R. G. Burns 		  1100

A New Instrument to Measure Charged and Neutral Cometary Dust Particles at Low and High Impact Velocities
T. Economou, J. A. Simpson, A. J. Tuzzolino 		  1101

Geophysical Results from Ramso Island in Lake Mien, an Impact Site in Southern Sweden
A. Ekelund 		  1102

Space Photographs of Drought in Africa
F. El-Baz 		  1103

Planetary Metamorphic Events in Unequilibrated EH Chondrites
A. El Goresy, D. S. Woolum, K. Ehlers, A. V. Ivanov 		  1104

Bushveld Complex, South Africa: is Rooiberg Felsite an Impactite?
W. E. Elston, D. Twist 		  1105

High-Pressure Crystal-Liquid Fractionation of Basaltic Magmas: a Phase-Equilibria Framework
D. Elthon 		  1106

Anomalies Induced in MG Isotopes by Sputtering
T. M. Esat, S. R. Taylor 		  1107

MG Isotope Composition of Ivory Coast Microtektites
T. M. Esat, S. R. Taylor 		  1108

Noble Gases in Grain Size Fractions of Lunar Anorthosite 60018: Trapped Xenon Isotopically Similar to Terrestrial Atmospheric Xenon
O. Eugster 		  1109

Single-Stage Exposure of the Lunar Highland Breccias 60018, 67435, and 67455
O. Eugster, S. Niedermann 		  1110

TI and MG Isotopic Measurements in CM and CV Meteorites
A. Fahey, J. N. Goswami, K. D. McKeegan, E. Zinner 		  1111

A Calculated Relative Volatility Sequence for Lithophile Refractory Trace Elements in the Solar Nebula
B. Fegley 		  1112

A Comparison of REE and Refractory Metal Oxidation State Indicators for the Solar Nebula
B. Fegley 		  1113

Predicted Chemical Models of the Deep Atmosphere of Uranus
B. Fegley, R. G. Prinn 		  1114

Discriminant Analysis of the Pristine Lunar Glasses: Implications for a Magma Ocean
M. M. Fernandez, J. W. Delano 		  1115

Uranium-Series Dates for Ice from Two Allan Hills Locations
E. L. Fireman 		  1116

The Assemblage Metal-Ca Inclusion in the Efremovka CV Chondrite
A. V. Fisenko, K. I. Ignatenko, L. F. Semjonova, A. K. Lavrukhina 		  1117

Distribution Coefficient of Argon in a Basalt/felspar System
D. E. Fisher 		  1118

Metamorphic Temperatures and Enstatite Chondrites
R. A. Fogel, P. C. Hess, M. J. Rutherford 		  1119

Nitrogen Isotope Studies of the Bencubbin Meteorite
I. A. Franchi, I. P. Wright, C. T. Pillinger 		  1120

Ancient Fractures in the Tharsis Region
R. A. Francis 		  1121

Apollo 16 Highland Rocks from Sample 63500: Preliminary Results of Geochemical Thermometry
M. Ya. Frenkel, M. I. Korina, E. V. Koptev-Dvornikov, A. A. Ariskin, A. A. Yaroshevsky 		  1122

Pseudocraters as Indicators of Ground Ice on Mars
H. Frey 		  1123

The Martian Crustal Dichotomy: Product of Accretion and not a Specific Event?
H. V. Frey, R. A. Schultz, T. A. Maxwell 		  1124

Crater Counts in the Transition Zone in Eastern Mars: Evidence for Common Resurfacing Events
H. Frey, A. M. Semeniuk, J. A. Semeniuk, S. Tokarcik 		  1125

Effects of Grain Sizes on the Spectral Reflectance of Mineral Mixtures -- Towards an Inversion Problem for Three Components Mixtures
N. Fujii, H. Azuma, K. Ito, M. Miyamoto 		  1126

Limits on the Extent of Chemical and Convective Isolation in the Earth's Interior
S. J. G. Galer, S. L. Goldstein, R. K. O'Nions 		  1127

Possible Impact Structures in Central Africa
J. B. Garvin 		  1128

A Remote Sensing of the Elgygytgyn Impact Crater
J. B. Garvin, R. A. F. Grieve 		  1129

Characteristics of the Venera and VEGA Landing Sites from Pioneer Venus Radar Data
J. B. Garvin, J. W. Head 		  1130

Dielectric Properties of Venus Landing Sites
J. B. Garvin, J. W. Head 		  1131

The Spacewatch Camera: a Progress Report
T. Gehrels, J. E. Frecker, R. S. McMillan, J. V. Scotti 		  1132

Earth's Atmosphere during the Archean as Seen from Carbon and Nitrogen Isotopic Analysis of Sediments
E. K. Gibson, L. P. Carr, I. Gilmour, C. T. Pillinger 		  1133

Laser Microprobe Study of Cosmic Dust (idps) and Potential Source Materials
E. K. Gibson, M. S. Sommer 		  1134

No Evidence for a 0.8-0.9 M.Y. Old Micro-Australite Layer in Deep-Sea Sediments
B. P. Glass 		  1135

Tectites and Impact Glasses: Specific Features of Microstructure
L. I. Glazovskaya, V. V. Golubkov 		  1136

Lithospheric Flexure and Shallow Faulting on the Moon
M. P. Golombek 		  1137

Extensional Tectonic Features as Indicators of Lithospheric Strength and Early Thermal Profiles on Ganymede
M. P. Golombek, W. B. Banerdt 		  1138

Carbonaceous Chondrites: Thermal Analysis by Differential Scanning Calorimetry (dsc)
J. L. Gooding 		  1139

Water-Ice in the Martian Regolith: Experimental Investigation of Lithologic Effects
J. L. Gooding 		  1140

Trapped Primary Silicate Liquid in Ureilites
C. A. Goodrich 		  1141

Micromorphometry of Lunar Breccias
B. Grabowska-Olszewska, M. Zbik 		  1142

A Search for Circum-Asteroidal Material Using a Stellar Coronagraph
J. Gradie 		  1143

Sulfur Deposition on Silicates: Effects on Band Strengths
J. Gradie 		  1144

Analytical Simulation of a 10-KM-DIAMETER Asteroid Impact Into a Terrestrial Ocean: Part 3--CRATERING Mechanics
L. B. Grant, S. Schuster, D. J. Roddy 		  1145

Microtektites at the Cretaceous/tertiary Boundary
G. Graup, J. Huth, U. Rast, B. Spettel 		  1146

Observations of Active Sulfur Flows: Implications for IO
R. Greeley, S. W. Lee 		  1147

Two-Body Models for Planetary Encounters: Failure Criteria and a Strategy for Their Systematic Evaluation
R. Greenberg, A. Carusi, G. B. Valsecchi 		  1148

The K/t Impact Event: Some Implications from the Evidence
R. A. F. Grieve, V. L. Sharpton 		  1149

Kamacite-Perryite Assemblages in the Kaidun III Meteorite
V. I. Grokhovsky, A. V. Ivanov 		  1150

The Origin of Chondrules and Clasts Bearing Calcic Plagioclase in Ordinary Chondrites
J. N. Grossman, A. E. Rubin 		  1151

Bulk Chemical Composition of a Fremdling from an Allende Type B Inclusion
L. Grossman, A. M. Davis, V. Ekambaram, J. T. Armstrong, I. D. Hutcheon, G. J. Wasserburg 		  1152

A Study of the Effect of Devitrification on Thermoluminescence in Type 3.4 Ordinary Chondrites
R. K. Guimon, G. E. Lofgren, D. W. G. Sears 		  1153

Laboratory Metamorphism of a Primitive Meteorite
R. K. Guimon, D. W. G. Sears, G. E. Lofgren 		  1154

Elgygytgyn Crater Glassy Bombs: from Impactites to Tektites
E. P. Gurov 		  1155

Implications for Substrate Volatile Distributions on Mars from Complex Crater Morphology and Morphometry
W. S. Hale-Erlich 		  1156

Lithospheric Loading and Tectonics of the Lunar Irregular Maria
J. L. Hall, S. C. Solomon 		  1157

Shock History of Ordinary Chondrites: Some H and L Antarctic-Non Antarctic Comparisons
M. Haq, F. A. Hasan, D. W. G. Sears 		  1158

Suspected Burnt-Out Comets: Outer Solar System Origin Confirmed
W. K. Hartmann, D. J. Tholen, D. P. Cruikshank 		  1159

Thermoluminescence Studies of Shock Loaded Oligoclase and Bytownite
C. P. Hartmetz, D. W. G. Sears, R. Ostertag 		  1160

The Manson, Iowa, Impact Structure and the Cretaceous-Tertiary Boundary Event
J. B. Hartung, G. A. Izett, C. W. Naeser, M. J. Kunk, J. F. Sutter 		  1161

Natural Thermoluminescence of Antarctic Meteorites: a Study of Thermal/radiation History and Pairing
F. A. Hasan, M. Haq, D. W. G. Sears 		  1162

A Hibonite-Rich Murchison Inclusion with Anomalous Oxygen Isotopic Composition
A. Hashimoto, R. W. Hinton, A. M. Davis, L. Grossman, T. K. Mayeda, R. N. Clayton 		  1163

Chemical Trends in Anorthosites of the Etagaulet Massif
L. A. Haskin, P. A. Salpas 		  1164

Analytical Simulation of a 10-KM-DIAMETER Asteroid Impact Into a Terrestrial Ocean: Part 2--ATMOSPHERIC Response
P. J. Hassig, M. Rosenblatt, D. J. Roddy 		  1165

Ishtar Terra, Venus: a Simple Model of Large-Scale Tectonic Convergence, Crustal Thickening, and Possible Delamination
J. W. Head 		  1166

Venus Global Tectonics: Tectonic Style and Evidence for Latitudinal Distribution of Tectonic Features
J. W. Head 		  1167

VEGA Landing Sites: Geological Characteristics of the Surrounding Region, Rusalka Planitia, Venus
J. W. Head, J. B. Garvin, D. B. Campbell, G. H. Pettengill, H. Masursky, R. S. Saunders, V. L. Barsukov, A. T. Basilevsky, Y. A. Surkov 		  1168

The Effect of Isotopic Abundance on Nomadic Chemistry
J. E. Heidenreich, M. H. Thiemens 		  1169

Dark-Floored Craters on Ganymede: Evidence for Devolatilized Impact Melt
P. Helfenstein 		  1170

Photometrically Determined Surface Physical Properties of Terrains on Ganymede
P. Helfenstein 		  1171

Dynamics of a Confined Lava Flow on Kilauea - of Rheology and Eruption Conditions
S. E. Heslop, H. Pinkerton, L. Wilson, J. W. Head 		  1172

Buckminsterfullerene, C60, and Siblings: Their Properties as Traps for Inert Gas Atoms
D. Heymann 		  1173

A Qualitative Laser-Raman Study of Graphitic Carbon in Allende
D. Heymann, E. Burke, J. Touret 		  1174

Carbon in Dark Inclusions of the Allende Meteorite
D. Heymann, C. C. A. H. van der Stap, R. D. Vis, H. Verheul 		  1175

Lunar Surface Neutrons and Gamma Rays Revisited
J. C. Higdon, E. F. Plechaty, E. H. Canfield, R. E. Lingenfelter 		  1176

Trace Elements and Calcium Isotopes in the Murchison Corundum-Hibonite Inclusion GR-1
R. W. Hinton, A. M. Davis 		  1177

The Search for the Scaling Laws of Impact Cratering: Recent Numerical Results
K. A. Holsapple 		  1178

Solar-Like Noble Gases in Terrestrial Diamonds
M. Honda, P. McConville, J. H. Reynolds, E. Roedder 		  1179

Magnetosphere Influences on the Evolution of Planetary Rings
L. L. Hood 		  1180

Lunar Composition and Structure: II. Theoretical Seismic Velocity Models
L. L. Hood, J. H. Jones 		  1181

Lunar Composition and Structure: III. Mantle Density Models and Implications for the Existence of a Metallic Core
L. L. Hood, J. H. Jones 		  1182

Distribution of Lunar Craters and Multi-Ring Basins: a Test for Lunar Polar Wandering
D. M. Hooper, T. A. Maxwell 		  1183

Effects of Elevation and Plains Thicknesses on Martian Crater Ejecta Morphologies for the Ridged Plains
V. M. Horner, R. Greeley 		  1184

Viking IRTM Studies of the Crater Curie
V. M. Horner, J. R. Zimbelman 		  1185

How do Collisional Outcomes Depend on Size Scale?
K. R. Housen, K. A. Holsapple 		  1186

Laboratory Simulations Relevant to CV Parent Body Alteration
R. M. Housley 		  1187

Possible CV Parent Body Alteration Processes
R. M. Housley 		  1188

A Spectroscopic Analog to the Silicate Component of Martian Dust
R. Huguenin, S. Harris, R. Carter 		  1189

On the Origin of Planetary Noble Gases
G. R. Huss, E. C. Alexander 		  1190

MG Isotopic Studies of CAI in C3V Chondrites
I. D. Hutcheon, J. T. Armstrong, G. J. Wasserburg, A. El Goresy 		  1191

New Data on the Bencubbin Polymict Stony-Iron Breccias
R. Hutchison 		  1192

ALUMINIUM-26 in a Murchison Hibonite?
T. R. Ireland 		  1193

Laboratory Synthesis of Calcium Dialuminate and Hibonite
T. R. Ireland 		  1194

Magnesium Isotopic Systematics of Murchison Refractory Inclusions
T. R. Ireland, T. M. Esat, W. Compston 		  1195

Are Hills Comet Showers the Cause of Geologic Cooling Events?
A. A. Jackson 		  1196

Sm-Nd and Rb-Sr Systematics of the SNC Meteorite ALHA 77005
E. Jagoutz 		  1197

Thermal Conductivity of Comet Surface Ice
B. M. Jakosky 		  1198

Are the Viking Lander Sites Representative of the Surface of Mars?
B. M. Jakosky, P. R. Christensen 		  1199

The Observed Day-To Variability of Mars Water Vapor
B. M. Jakosky, M. R. Lapointe, R. W. Zurek 		  1200

A New Look at Rnaa Data for Lunar Fragment-Laden Impact Melts
O. B. James 		  1201

A Review of Recent Research on the Apollo 16 Site
O. B. James 		  1202

A Potpourri of Regolith Breccias: Distinctive "new" Samples of the Lunar Surface
E. A. Jerde, P. H. Warren, G. H. Heiken, D. T. Vaniman 		  1203

Quantitative Spectral Mixture Modeling Applied to Viking Lander Images
P. E. Johnson, M. Smith, J. B. Adams 		  1204

Experimental Partitioning of ag, mo, PB and pd Between Iron Metal and Troilite
J. H. Jones, T. M. Benjamin, C. M. Maggiore, C. J. Duffy, S. R. Hart 		  1205

Lunar Composition and Structure: I. a Method for Calculating Mantle Mineralogies
J. H. Jones, L. L. Hood 		  1206

Arcuate Ground Undulations, Gelifluxion-Like Features and "front Tori" in the Northern Lowlands on - do they Indicate?
H.-P. Jons 		  1207

Volatile/mobile Trace Elements in LL4-6 Chondrites
P. W. Kaczaral, M. E. Lipschutz 		  1208

Compositional Characterization of Enstatite Chondrites
G. W. Kallemeyn, J. T. Wasson 		  1209

Morphologic Variations of Martian Rampart Crater Ejecta and Their Dependencies and Implications
J. S. Kargel 		  1210

Thermoluminescence and the Metamorphic History of the CO Chondrites
B. D. Keck, D. W. G. Sears 		  1211

Deuterium Exchange during Acid-Demineralisation
J. F. Kerridge, R. Shipp, S. Chang 		  1212

Smooth Plains Formation on Mercury
W. S. Kiefer, B. C. Murray 		  1213

Dynamic Models for Venus' Long-Wavelength Geoid
W. S. Kiefer, M. A. Richards, B. H. Hager, B. G. Bills 		  1214

Origin of the Moon: a Preliminary Numerical Study of Colliding Planets
M. E. Kipp, H. J. Melosh 		  1215

Identification of Cosmogenic Argon Components in Allende by Laser Microprobe
C. Kirschbaum 		  1216

Morphology of Large Valleys on Hawaii: Implications for Groundwater Sapping and Comparisons to Martian Valleys
R. C. Kochel, J. O. Piper 		  1217

St. Helena Island, Cameroon, Darfur, Rungwe Volcanoes, Walvis Ridge, Benue Trough, Bangui Anomaly: Different Features Tied to One Radial-Concentric Superstructure of the Congo Craton
G. G. Kochemasov 		  1218

Muong Nong Type Tektites from the Moldavite and North American Strewn Fields?
C. Koeberl 		  1219

Blue Glass from Zhamanshin Impact Crater (ussr)
C. Koeberl, D. D. Badyukov, M. A. Nazarov 		  1220

Apollo 16 Lunar Highland Rocks from Sample 63500: Bulk Composition and Mineral Chemistry
M. I. Korina, N. N. Kononkova 		  1221

Was Hibonite the Carrier of the Super-Refractory REE Component in the Solar Nebula?
A. S. Kornacki 		  1222

Fractionation Patterns among Siderophile and Lithophile Refractory Trace Elements in Cai's: Implications for Grain Transport in the Solar Nebula
A. S. Kornacki, B. Fegley 		  1223

Non-Chondritic Ni/co Ratios in Metal Associated with Apollo 16 Regolith and Other Samples from the Lunar Highlands. Part 1. the Observation and Problem
R. L. Korotev 		  1224

Non-Chondritic Ni/co Ratios in Metal Associated with Apollo 16 Regolith and Other Samples from the Lunar Highlands. Part 2. Possible Reasons and Implications
R. L. Korotev 		  1225

Trace Element Concentrations in the Fine Grain-Size Fractions of Experimental Regoliths
R. L. Korotev, T. H. See, F. Horz 		  1226

Gravity-Spreading Origin of the Venusian Tesserae
R. C. Kozak, G. G. Schaber 		  1227

Microdistribution of Germanium in the Allan Hills A77081 Winonaite
A. Kracher 		  1228

Ice in Solar System
M. S. Krass 		  1229

O/h in the Solar Nebula Gas in the Zones of C2, C3, and UOC Chondrule Formation
D. A. Kring 		  1230

Accretion Rate of Extraterrestrial Matter: an Iridium Profile for the Last 67 MA
F. T. Kyte 		  1231

Fractal Phenomena in the Solar System: a Heuristic Suggestion
B. Lang, A. V. Vityazev 		  1232

Ion Microprobe Sensitivities and Their Application to Multielement Analysis of LDEF Impact Residues
G. Lange, S. Eigner, E. Igenbergs, E. K. Jessberger, H. Kuczera, D. Maas, S. Sutton, U. Weishaupt, E. Zinner 		  1233

Impact Vaporization and the Accretion of Icy Planets
M. A. Lange, T. J. Ahrens 		  1234

An Overview of the Shergotty Consortium Studies
J. C. Laul 		  1235

Chemistry of Luna 24 Grain Size Separates
J. C. Laul, O. D. Rode 		  1236

Rare Earth Patterns in Shergottite Phosphates
J. C. Laul, M. R. Smith 		  1237

Elemental Composition of Chondrules of Some Structural Types in the Ochansk H4, Saratov L3-4, Kainsaz CO Chondrites
A. K. Lavrukhina, A. Yu. Ljul, G. V. Baryshnikova, G. M. Kolesov 		  1238

H2O, c, xe, in the Impact-Metamorphosed Specimens of Carbonaceous Chondrites Murray, Murchison CM
A. K. Lavrukhina, Z. K. Milnikova, S. V. Pershin, D. Vu. Minh, Yu. A. Shukolyukov 		  1239

IRTM Thermal and Albedo Observations of Syrtis Major
S. W. Lee 		  1240

Collisional Sticking Phenomena as Related to Growth of Planetary Embryo
J. Leliwa-Kopystynski, Z. Czechowski 		  1241

Thermal Inertias for the Elysium and Aeolis Quadrangles of Mars
L. A. Leshin, J. R. Zimbelman 		  1242

Diffusive Mass Fractionation of Atmospheric Xenon
K. Liffman, D. Heymann 		  1243

Mass Fractionation of Noble Gases due to Adsorption
K. Liffman, D. Heymann 		  1244

Lunar Magnetization Concentrations (magcons) Antipodal to Young Large Impact Basins
R. P. Lin, K. A. Anderson, L. L. Hood 		  1245

Conductivities of Silicate Melts; Applications to Lunar Smelting
D. J. Lindstrom, L. A. Haskin, K. W. Semkow, R. H. Lewis 		  1246

Electrochemical Monitoring of Crystal Growth from Silicate Melts; Preliminary Conductivity Studies
D. J. Lindstrom, K. W. Semkow 		  1247

Diversity of Rock Types in Apennine Front Breccias
M. M. Lindstrom 		  1248

TI3+ in Meteoritic and Synthetic Hibonite: a New Oxygen Barometer
D. Live, J. R. Beckett, F.-D. Tsay, L. Grossman, E. Stolper 		  1249

Fractional Crystallization of Ultramafic Mare Magmas
J. Longhi 		  1250

The Architecture of the Ol-Pl Pseudoternary Liquidus Diagram
J. Longhi, V. Pan 		  1251

Physiographic Features on Venus and Earth: a Photogeologic Comparison
P. D. Lowman, J. B. Garvin 		  1252

More on RECENT(?) Dark Volcanic Patches in the Valles Marineris, Mars
B. K. Lucchitta 		  1253

Northern Sinks on Mars?
B. K. Lucchitta, H. M. Ferguson, C. Summers 		  1254

Hydrogen Cyanide Polymers in the Solar System
R. Ludicky, J. Nelson, C. Matthews 		  1255

High Resolution Electron Microscopy of Carbonaceous Material from ci, cm, cv, and H Chondrites
G. R. Lumpkin 		  1256

Influence of Pressure and Temperature on Natural Graphitization: Thermal Histories of Some Carbonaceous Meteorites
G. R. Lumpkin 		  1257

Ubiquitous Feo-Rich Pyroxenes in Enstatite Chondrites: Implications for Metamorphism and Brecciation
D. Lusby, E. R. D. Scott, K. Keil 		  1258

Sand-Grain Response in Planetary Atmospheres
D. J. MacKinnon 		  1259

Refinements and Developments on the Stratospheric Dust Database and Classification Scheme
I. D. R. MacKinnon, D. S. McKay 		  1260

Surface Morphology of Cometary Nuclei
M. C. Malin, J. R. Zimbelman 		  1261

Experimental Partitioning Studies of Siderophile Elements amongst Lithophile Phases: Preliminary Results Using PIXE Microprobe Analysis
D. J. Malvin, M. J. Drake, T. M. Benjamin, C. J. Duffy, M. Hollander, P. S. Z. Rogers 		  1262

Neutron Exposure Age of the Cape York Iron Meteorite
K. Marti, S. V. S. Murty, K. Nishiizumi 		  1263

Breccia 67015: a Comparison with Other North Ray Crater Ejecta
U. B. Marvin, M. M. Lindstrom 		  1264

Ages of Rocks and Channels in Prospective Martian Landing Sites of Mangala Valles Region
H. Masursky, M. G. Chapman, A. L. Dial, M. E. Strobell 		  1265

The IRAS Asteroid and Comet Survey: a Progress Report
D. L. Matson, G. J. Veeder, E. T. Tedesco, L. A. Lebofsky 		  1266

Evolution of the Terrestrial Planets: Accretion, Atmosphere Formation and Thermal History
T. Matsui, Y. Abe 		  1267

Oxygen Isotope Variations Within Allende Refractory Inclusions
T. K. Mayeda, R. N. Clayton, H. Nagasawa 		  1268

Cosmogenic Nuclide Production in Ellipsoidal Meteoroids
A. F. McDowell, L. E. Nyquist 		  1269

High-Resolution Color Images of Mars
A. S. McEwen 		  1270

Petrology of Granulitic Breccia Clasts from Feldspathic Fragmental Breccia 67975
J. J. McGee 		  1271

Precursor(s) of Lunar Granulitic Rock 67415: Monomict Noritic Anorthosite or Polymict Breccia?
J. J. McGee 		  1272

Nature of Early Deformation in the Southwestern Part of the Michipicoten Greenstone Belt, Ontario
G. E. McGill, C. H. Shrady 		  1273

Pyroxene Distribution Coefficients, the Shergotty Parent Melt, and Metasomatic Alteration
G. McKay, J. Wagstaff, L. Le 		  1274

Hydrogen and Magnesium Isotopic Abundances in Aluminum-Rich Stratospheric Dust Particles
K. D. McKeegan 		  1275

Complex Igneous Processes on the Shergottite Parent Body
H. Y. McSween 		  1276

Evidence for Liquid Water "lava" Eruptions on Europa in the White Line Feature Agenor Linea
T. A. Meier 		  1277

Spectral Classification of Dark Lineations on Europa and Evidence for Plume-Style Water Eruption Resurfacing
T. A. Meier 		  1278

A Martian Large-Crater Origin for the SNC Meteorites
H. J. Melosh, A. M. Vickery 		  1279

The Application of Gamma-Ray Spectroscopy to the Climatology of Mars
A. E. Metzger, J. R. Arnold, R. C. Reedy, J. I. Trombka, E. L. Haines 		  1280

Precise Determination of REE and Other Elements in Individual Chondrules from the Allende (CV3) Chondrite
K. Misawa, N. Nakamura 		  1281

Petrology, Chronology and Chemistry of Basaltic Clasts from Mesosiderites
D. W. Mittlefehldt, B. M. Bansal, C.-Y. Shih, H. Wiesmann, L. E. Nyquist 		  1282

Anomalous Total Dose of Esr Data in Danish Calcite at K-T Boundary
Y. Miura 		  1283

Differences in Formation Condition and Process of Terrestrial and Extraterrestrial Plagioclases
Y. Miura 		  1284

Terrestrial and Extraterrestrial Osumilite-Group Minerals and Potash Feldspars
Y. Miura 		  1285

Infrared Diffuse Reflectances (2.5-25UM) of the Murchison and Allende Meteorites
M. Miyamoto 		  1286

Melting Experiments on an LL Chondrite
M. Miyamoto, D. S. McKay, G. E. Lofgren, M. B. Duke 		  1287

Landform Identification in Lunar Radar Images
H. J. Moore, T. W. Thompson 		  1288

Oxygen Isotope Fractionation in the Primitive Solar Nebula: Bulk Properties
G. E. Morfill, R. N. Clayton 		  1289

Oxygen Isotope Fractionation in the Primitive Solar Nebula: Theory
G. E. Morfill, R. N. Clayton 		  1290

Dislocation Substructures of Olivine Crystals from Pallasite Meteorites
H. Mori 		  1291

Evidence for Hematite on Mars: Spectral Properties of Ferric Iron Phases in Annealed, Al-Rich Precipitates of Fe-Al Sulfate Salt Solutions
R. V. Morris, H. V. Lauer 		  1292

Implications for Lunar Composition from an Investigation of the Nakamura Seismic Velocity Model
S. W. Mueller, R. J. Phillips 		  1293

Remote Sensing and Geologic Studies of the Lassell Region of the Moon
A. Muller, B. R. Hawke, P. G. Lucey, C. M. Pieters 		  1294

Tektite-Like Bodies from Lonar Crater, India
A. V. Murali, M. E. Zolensky, M. A. Sommer, D. P. Blanchard 		  1295

Break-Up of Dark Terrain and the Formation of Bright Terrain on Ganymede: Evidence for Strike-Slip Faulting
S. L. Murchie, J. W. Head 		  1296

CO2-DRIVEN Water Volcanism on Ganymede and its Implications for Volcanic and Tectonic Styles
S. L. Murchie, J. W. Head 		  1297

Global Reorientation of Ganymede by the Basin Gilgamesh: Models and Evidence from Tectonic Patterns
S. L. Murchie, J. W. Head 		  1298

Sequence of Grooved Terrain Formation on Ganymede
S. L. Murchie, J. W. Head, P. Helfenstein, J. B. Plescia 		  1299

Spinel-Perovskite Rims: Constraints on the Thermal Histories of Ca-Al Inclusions
M. T. Murrell, D. S. Burnett 		  1300

Pursuit of Solar Nitrogen: Nitrogen Components in the Pesyanoe Meteorite
S. V. S. Murty, K. Marti 		  1301

Deconvolution of Spectra for Intimate Mixtures
J. F. Mustard, C. M. Pieters, S. F. Pratt 		  1302

Reduction Kinetics of Olivine and Oxygen Fugacity Environment during Chondrule Formation
H. Nagahara 		  1303

Trace Element Concentrations in Microtektites from Barbados and Dsdp-Core from the Caribbean Sea and Gulf of Mexico
H. Nagasawa, T. Fukuoka, B. P. Glass 		  1304

CE Anomaly in Chemically Separated Fractions of Sedimentary Rocks as an Indicator for Redox Environment: a Preliminary Study
H. Nagasawa, M. Kakiuchi, T. Fukuoka, K. Suwa 		  1305

REE Abundances and Pb-Pb Isotopic Systematics of the Lunar Meteorite, YAMATO-82192
N. Nakamura, D. M. Unruh, M. Tatsumoto, T. Fujiwara 		  1306

Solid Sulfur in Vacuum: Sublimation Effects on Surface Microtexture, Color, and Spectral Reflectance, and Applications to Planetary Surfaces
D. B. Nash 		  1307

Cretaceous/tertiary Event: Geochemistry of Turkmenia K/t Sections
M. A. Nazarov, L. D. Barsukova, G. M. Kolesov, I. V. Nizhegorodova, A. S. Alekseev, K. N. Amanniyazov 		  1308

Properties of Materials in the Interiors of Uranus and Neptune
W. J. Nellis, D. C. Hamilton, N. C. Holmes, A. C. Mitchell, H. B. Radousky, F. H. Ree, M. Ross, M. Nicol 		  1309

The Role of Fluidization in the Emplacement and Alteration of the Suevite Impact Melt Deposit at the Ries Crater, West Germany
H. E. Newsom, G. Graup, T. Sewards, K. Keil 		  1310

Titanium Isotopes in Chondrules and Other "separates" from Carbonaceous Chondrites
S. Niemeyer 		  1311

Mass Spectrometric Study of the Mercury Isotopes in the Allende Meteorite: a Preliminary Investigation
A. O. Nier, D. J. Schlutter 		  1312

Hot SPOT Tectonics on Venus: Implications for Rifting and Doming
A. M. Nikishin 		  1313

The Statistics of Circular Features on the Plains of Venus
O. V. Nikolaeva, L. B. Ronca, A. T. Basilevsky 		  1314

Depth Variation in Cosmogenic Radionuclide Production in Very Large Meteorites: Allende and DRP78002-9
K. Nishiizumi, D. Elmore, P. W. Kubik, J. R. Arnold 		  1315

Age of Antarctic Meteorites and Ice II
K. Nishiizumi, D. Elmore, P. W. Kubik, G. Bonani, M. Suter, W. Wolfli, J. R. Arnold 		  1316

Kinetic Studies of the Hydration of Amorphous Mg-Sio Smokes
J. A. Nuth, R. Nelson, B. Donn, R. K. Khanna 		  1317

SR Isotopic Systematics of EETA 79001 Glass
L. Nyquist, H. Wiesmann, C.-Y. Shih, B. Bansal 		  1318

Design Considerations for a Titan Aerosol Collector
V. R. Oberbeck, D. P. O'Hara, G. C. Carle 		  1319

Preliminary Identification of Different Meteoroid Families Impacting the Lunar Surface
J. Oberst, Y. Nakamura 		  1320

Eocene Microtektites and Clinopyroxene-Bearing Spherules
J. A. O'Keefe 		  1321

Effect of Planetary Gravity and Impact Size on Crater Maximum Penetration and Excavation Depth
J. D. O'Keefe, T. J. Ahrens 		  1322

Shapes of Asteroids from Radar
S. J. Ostro, R. Connelly 		  1323

What can a Lightcurve Tell us about an Asteroid's Shape?
S. J. Ostro, R. Connelly 		  1324

A Gas-Rich Fragment of the Allende Meteorite: "solar" and "planetary" Trapped Gases
R. L. Palma, D. Heymann 		  1325

Trace Elements in Forsterite-Rich Inclusions in Allende
H. Palme, B. Spettel, I. M. Steele 		  1326

A Pre-Phobos Assessment of the Composition of the Martian Moons Based on Viking, Mariner 9 and Groundbased Data
K. D. Pang, J. M. Ajello, J. I. Lunine, J. Wagner, B. Hapke, E. Wells 		  1327

CR Isotopic Anomalies in FUN and Non-Fun Refractory Inclusions
D. A. Papanastassiou, G. J. Wasserburg 		  1328

A New Ca-Al in Coarse-Grained Ca-Al Inclusions
J. M. Paque, J. R. Beckett, E. Stolper 		  1329

Topography due to Horizontal Stresses in a Ductile Lithosphere of Variable Thickness: Application to Venus
E. M. Parmentier 		  1330

Continental Crust Genesis on Earth: Need for Systematic nd Isotopic Study of Terrains 3.8 GA to Present
J. Patchett, N. Arndt 		  1331

Terrace Width Variations in Complex Lunar Craters
S. J. Pearce, H. J. Melosh 		  1332

The Origin of Ferrous Zoning in Allende Chondrule Olivines
J. A. Peck 		  1333

Volatile Inventory of Mars
R. O. Pepin 		  1334

Isostatic Uplift in Magmatic Systems: Application to the Tharsis Region of Mars
R. J. Phillips, A. A. Finnerty 		  1335

Compositional Information for the Moon: Some Characteristics of Current Near-Ir Spectra (telescopic and Laboratory)
C. M. Pieters 		  1336

Oxidized Basalts on the Surface of Venus: Compositional Implications of Measured Spectral Properties
C. M. Pieters, W. Patterson, S. Pratt, J. W. Head, J. Garvin 		  1337

Mapping Geomorphic Provinces on Solid Planets: a Quantitative Example from Earth
R. J. Pike 		  1338

Scale Dependence of Planetary Surface Slope is Curvilinear
R. J. Pike 		  1339

Variance Spectra of Representative 1:62,500-SCALE Topographies: a Terrestrial Calibration for Planetary Roughness at 0.3 KM to 7.0 KM
R. J. Pike 		  1340

Secular Change in South Polar Sedimentary Processes Inferred from the Morphologies and Ages of Layered and Pitted Terrain
J. Plaut, E. Guinness, R. Arvidson, R. Kahn 		  1341

Tectonics of the Elysium Region, Mars
J. B. Plescia 		  1342

Rare Gas Reservoirs and Earth Degassing
D. R. Porcelli, J. O. H. Stone, R. K. O'Nions 		  1343

Further Observations of Sodium on Mercury
A. E. Potter, T. H. Morgan 		  1344

Deposition and Erosion on Martian Cratered Terrains as Determined by Viking Orbiter Multispectral Image and Thermal Observations
M. Presley, R. Arvidson 		  1345

ALHA84025: a Second Brachina-Like Meteorite
M. Prinz, M. K. Weisberg, C. E. Nehru, J. S. Delaney 		  1346

North Haig and Nilpena: Paired Polymict Ureilites with Angra DOS Reis-Related and Other Clasts
M. Prinz, M. K. Weisberg, C. E. Nehru, J. S. Delaney 		  1347

Mineralogical Studies of Ureilites: Minor Phases and Inclusions and Their Implications
M. Prinz, M. K. Weisberg, C. E. Nehru, J. S. Delaney, K. Yanai 		  1348

Search for Correlated Isotope Effects in Allende Cais
C. A. Prombo, G. W. Lugmair 		  1349

Dynamic Crystallization Experiments on a Pyroxene-Olivine Chondrule Composition
P. M. Radomsky, R. P. Turrin, R. H. Hewins 		  1350

Crustal Block Model of the Tharsis Region, Mars
J. Raitala, R. S. Saunders 		  1351

Origin of Compressional Lithospheric Stresses of the Tharsis Region, Mars
J. T. Raitala, R. S. Saunders 		  1352

Fragments of Rock from a Probable Impact Ejecta Deposit in Ordovician Sediments of Northern Illinois
W. F. Read 		  1353

Nuclide Production by Primary Galactic-Cosmic Protons
R. C. Reedy 		  1354

Deformation, Transformation, and Thermal Annealing of Experimentally Shocked Single Crystal Quartz
A. Rehfeldt-Oskierski, D. Stoffler, U. Hornemann 		  1355

First Results of a Petrographic Comparison of Pseudotachylite from Vredefort, Sudbury, and from Endogenic-Tectonic Settings
W. U. Reimold, B. O. Dressler, D. Tao 		  1356

- General Witwatersrand Basin PHENOMENON!
W. U. Reimold, P. Fletcher, P. A. Snowden, J. D. Wilson 		  1357

Textures of Experimentally Shocked (5.1-35.5 Gpa) Witwatersrand Quartzite
W. U. Reimold, F. Horz 		  1358

Low Temperature Structures in the Iron Meteorite Dayton
K. B. Reuter, J. A. Kowalik, J. I. Goldstein 		  1359

Layered Convection in Proto-Stellar Nebula: Implications for Planetary Formation and Titus-Bode Laws
A. Rice 		  1360

Silica-Rich Glass and Trydimite in a Chondritic Porous Aggregate: Evidence for Stratospheric Contamination of Interplanetary Dust Particles
F. J. M. Rietmeijer 		  1361

Fine-Grained Silicates in a Chondritic Interplanetary Dust Particle are Evidence for Annealing in the Early History of the Solar System
F. J. M. Rietmeijer, D. S. McKay 		  1362

The Earth-Moon Connection
A. E. Ringwood 		  1363

The Making of the Moon
A. E. Ringwood 		  1364

A Method for Calculating the Non-Mass Isotopic Fractionation Factor
F. Robert 		  1365

Digital Inventory of Martian Impact Craters, Ejecta Blankets and Selected Morphologic Parameters
D. J. Roddy, N. K. Robertson, C. L. Mardock 		  1366

Analytical Simulation of a 10-KM-DIAMETER Asteroid Impact Into a Terrestrial Ocean: Part 1--SUMMARY
D. J. Roddy, S. Schuster, M. Rosenblatt, L. B. Grant, P. J. Hassig, K. N. Kregenhagen 		  1367

A Morphological Catalogue of Lunar Craters: a Preliminary Study
Zh. F. Rodionova, V. V. Shevchenko, A. A. Karlov, T. F. Smolyakova 		  1368

Tidal Heating in Viscoelastic Models of io and Europa
M. N. Ross, G. Schubert 		  1369

Ground Patterns on Earth and Mars
L. A. Rossbacher 		  1370

The G-Scale and Planetary Megageomorphology: how Big is it Really?
L. A. Rossbacher 		  1371

Mars: Seasonally Variable Radar Reflectivity II
L. E. Roth, R. S. Saunders, G. S. Downs, G. Schubert 		  1372

Carbonates on Mars: Searching the Mariner 6 and 7 IRS Measurements
T. L. Roush, D. Blaney, T. B. McCord, R. B. Singer 		  1373

The Continuous Nebular Fractionation Sequence Within H-Group Chondrites
A. E. Rubin, G. W. Kallemeyn, J. T. Wasson 		  1374

Primaevel Lunar Satellites
S. K. Runcorn 		  1375

Analyses of Apollo 15 Green Glasses: Groupings and Their Spatial Relationships
G. Ryder 		  1376

Apollo 15 Olivine-Normative Mare Basalts on the Apennine Front: Observations and Possible Interpretations
G. Ryder 		  1377

The Volcanic and Local Origin of Apollo 15 KREEP Basalts
G. Ryder 		  1378

Diversity of Impact Melt Compositions at the Apennine Front
G. Ryder, P. D. Spudis 		  1379

Additional Basalts from Consortium Breccia 14321
P. A. Salpas, L. A. Taylor, M. M. Lindstrom 		  1380

Apollo 17 Kreepy Basalts: Pristine Basaltic Breccias
P. A. Salpas, L. A. Taylor, M. M. Lindstrom 		  1381

A Potpourri of Clasts from Apollo 14 Including Troctolite and Granite
P. A. Salpas, L. A. Taylor, M. M. Lindstrom 		  1382

The First Apollo 17 Ferroan Anorthosite: its Significance Relative to Mg-Suite Highland Clasts
P. A. Salpas, L. A. Taylor, M. M. Lindstrom 		  1383

Laboratory Heating of an Interplanetary Dust Particle: Comparisons with an Atmospheric Entry Model
S. A. Sandford 		  1384

The World's Smallest Acid Residue: the Source of the 6.8 um Band Seen in Some IDP Spectra
S. A. Sandford 		  1385

Io: Shield Volcanism, Tidally Forced Viscous Heating, and the Shift of Active Volcanism Eastward from the Sub-Jupiter and Anti-Jupiter Points
G. G. Schaber 		  1386

Venera 15/16 and Arecibo Radar Images of Venus: Complementary Data Sets
G. G. Schaber, R. C. Kozak 		  1387

Cleopatra Crater on Venus: New Evidence for a Volcanic Origin
G. G. Schaber, R. C. Kozak, H. Masursky 		  1388

The Geometry of Furrows on Ganymede
P. M. Schenk, W. B. McKinnon 		  1389

Experimental Investigation of Crater Formation Dynamics
R. M. Schmidt, C. R. Wauchope, H. E. Watson 		  1390

Determination of Carbon Isotopes in Lunar Soil by Accelerator Mass Spectrometry
R. J. Schneider 		  1391

Particles Associated with Impact Features in the Main Electronics Box (meb) Thermal Blanket from the Solar Max Satellite
L. S. Schramm, R. A. Barrett, M. L. Lieurance, D. S. McKay, S. J. Wentworth 		  1392

Internal Electron Exchange Reactions in Synthetic Magmas
H. E. Schreiber 		  1393

Oxygen Diffusion and Redox Kinetics in a Geochemical Melt System
H. D. Schreiber, S. J. Kozak, K. K. McManus 		  1394

Early Changes in Gradation Styles and Rates on Mars
P. H. Schultz, D. Britt 		  1395

Experimental Evidence for Non-Proportional Growth of Large Craters
P. H. Schultz, D. E. Gault 		  1396

Impact Vaporization: Late-Time Phenomena from Experiments
P. H. Schultz, D. E. Gault 		  1397

Momentum Transfer from Oblique Impacts
P. H. Schultz, D. E. Gault 		  1398

Impacts of Hemispherical Granular Targets: Implications for Global Impacts
P. H. Schultz, D. E. Gault, D. Crawford 		  1399

Chondritic Impact Melts and Cratering Processes on Asteroids
E. R. D. Scott, P. Maggiore, G. J. Taylor, K. Keil, D. Szuwalski 		  1400

Experimental Regolith Evolution at High Impact Velocities
T. H. See, S. Smrekar, F. Cardenas, F. Horz, M. J. Cintala 		  1401

Depletions of Chromium and Vanadium in the Lunar Mantle
S. Seifert, A. E. Ringwood 		  1402

Characteristic Structures of the Highland Boundary on Mars: Evidence against a Single Mega-Impact Event?
A. M. Semeniuk, H. Frey 		  1403

Rb-Sr Chronology of Two High-K Mare Basalt Clasts from Breccia 14304
C.-Y. Shih, B. M. Bansal, H. Wiesmann, E. J. Dasch, L. E. Nyquist 		  1404

Elemental Analysis of Iron Meteorites by Glow Discharge Mass Spectrometer
T. Shimamura, H. Nagai, M. Honda 		  1405

Connolly Basin: a Probable Eroded Impact Crater in Western Australia
E. M. Shoemaker, C. S. Shoemaker 		  1406

Extinct Jupiter-Family Comets and Cratering Rates on the Galilean Satellites
E. M. Shoemaker, R. F. Wolfe, C. S. Shoemaker 		  1407

Petrology of Luna 24 Grain Size Separates
S. B. Simon, J. J. Papike, D. C. Gosselin 		  1408

Agglutinate Melting Mechanisms II: Shocked Lunar Soil Mixtures
S. B. Simon, J. J. Papike, F. Horz, T. H. See 		  1409

73235,82 (pomegranate): an Assemblage of Lunar Zircon with Unique Overgrowth
J. M. Smith, C. Meyer, W. Compston, I. S. Williams 		  1410

Separation Effects of Composition, Illumination Geometry, and Calibration in Viking 1 and 2 Multispectral Images
M. O. Smith, J. B. Adams, P. E. Johnson 		  1411

Refined Strain Analysis and Magnetic Anisotropy Measurements for the Parnallee Chondrite
D. S. Sneyd, H. Y. McSween, N. B. Woodward, N. Sugiura, D. W. Strangway 		  1412

Secular Cooling of the Earth as a Source of Intraplate Stress
S. C. Solomon 		  1413

A Test of the Hypothesis that Impact-Induced Fractures are Preferred Sites for Later Tectonic Activity
S. C. Solomon, E. D. Duxbury 		  1414

Volatile Determinations of Individual Fluid Inclusions Within the 3.4 B.Y. North Pole Barites from the Warrawoona Group, Northwestern Australia
M. A. Sommer, E. K. Gibson 		  1415

Io's Present High Dissipation State may BE Stable: Results of a Coupled Orbital-Thermal Evolution Calculation
T. Spohn, H. J. Fischer 		  1416

A Chemical and Petrological Model of the Lunar Crust
P. D. Spudis, P. A. Davis 		  1417

Olivine in Extraterrestrial Samples: Observations Allowing Determination of Affinity of Single Olivine Grains
I. M. Steele 		  1418

Contrasting Forsterite Compositions for C2, C3, and UOC Meteorites: Evidence for Divergence from Common Parent
I. M. Steele, J. V. Smith 		  1419

The Mechanical Interaction of Comets with the Interstellar Medium
S. A. Stern 		  1420

The SPARTAN and Champs Data - and Assessment
S. A. Stern, C. A. Barth 		  1421

New Formulas for the Evolution of Planetesimal Velocities
G. R. Stewart, G. W. Wetherill 		  1422

Cone Crater Consortium, Apollo 14: (2) Precursor Igneous Rocks and Ages of Polymict Breccias
D. Stoffler, S. Lingner, K. Heusser, E. K. Jessberger, H. Palme, B. Spettel, H. Wanke 		  1423

Terrestrial Noble Gas Inventories and Early Earth History
J. O. H. Stone, D. R. Porcelli, R. K. O'Nions 		  1424

Fault Tectonics of Terrestrial Planetary Bodies
N. Stovickova 		  1425

Color/albedo Distribution of Soil and Rock Surfaces at the Viking 1 Landing Site
E. L. Strickland 		  1426

Global Dust-Storm Fallout and Current Dust Accumulation in Low Thermal Inertia Regions on Mars: not Proven
E. L. Strickland 		  1427

Properties of Surface Units of the Central Equatorial Region of Mars
E. L. Strickland 		  1428

Are Comets Responsible for the Period of Heavy Bombardment?
R. G. Strom 		  1429

On the Possible Transport of Volatile Trace Elements in Meteorite Parent Bodies
N. Sugiura, J. Arkani-Hamed, D. W. Strangway 		  1430

Stability of Salt Hydrates in Martian Regolith
O. M. Suleimenov, M. Yu. Zolotov, I. L. Khodakovsky 		  1431

Uranium, Thorium, and Potassium in the Venusian Rock at the Landing Sites of Vegas 1 and 2
Yu. A. Surkov, F. F. Kirnozov, V. N. Glazov, A. G. Dunchenko, L. P. Tatsy, O. P. Sobornov 		  1432

Venus Rock Composition at the VEGA 2 Landing Site
Yu. A. Surkov, L. P. Moskalyova, V. P. Kharyukova, A. D. Dudin, G. G. Smirnov, S. Ye. Zaitseva 		  1433

Water Vapor Content Profile in the Venusian Atmosphere According to the Results of Measurements from Vegas 1 and 2
Yu. A. Surkov, O. P. Shcheglov, M. L. Ryvkin 		  1434

PIXE Trace Element Analyses of Metal, Troilite and Schreibersite in Iron Meteorites
S. R. Sutton, J. S. Delaney, J. V. Smith, M. Prinz 		  1435

Collapse Structures in the Appenine Bench Formation and Their Influence on the Formation of Mozart and Hadley Rilles
G. A. Swann 		  1436

I-Xe and 40AR-39AR Ages of Chainpur Chondrules
T. D. Swindle, M. W. Caffee, C. M. Hohenberg 		  1437

Melting of Mafic and Felsic Sources to Produce the Hree-Depleted Dacites of the Michipicoten Greenstone Belt, Ontario
P. J. Sylvester, K. Attoh, K. J. Schulz 		  1438

Mineralogical Studies of Augite-Bearing Clasts in Lunar Highland Regolith Breccia, 60019 and Lunar Meteorites
H. Takeda, M. Miyamoto, C. Galindo, T. Ishii 		  1439

Mineralogy of Augite-Bearing Ureilites, and Some Hypotheses on the Origin of Ureilites
H. Takeda, O. Tachikawa, H. Toyoda 		  1440

The Youngest Channel System on Mars
K. L. Tanaka, D. H. Scott 		  1441

Water in Ancient Moon?: Possible Oxic Alteration of 14310
T. Tanaka, H. Shimizu, K. Shibata, A. Masuda 		  1442

Valles - and Tectonics
K. L. Tanaka, N. E. Witbeck, D. H. Scott 		  1443

VLT Basalts from Apollonious Region: Geochemical Identification
L. S. Tarasov, A. F. Kudryashova, V. B. Baryshev, G. N. Kulipanov, A. N. Skrinsky 		  1444

Geochemistry of Incompatible Elements in Mineral-Rock Systems of Luna 24 Basalts
L. S. Tarasov, A. F. Kudryashova, A. S. Semenova, A. V. Ivanov, V. B. Baryshev, G. N. Kulipanov, A. N. Skrinsky 		  1445

Lead Isotopes from Green Glass of an Apollo 15 Soil: a Search for Primitive Lunar Lead
M. Tatsumoto, W. R. Premo, D. M. Unruh 		  1446

Viscous Flow in the System Albite-Diopside
P. Tauber, J. Arndt 		  1447

Olivine/melt Fe/mg Kd's <0.3: Rapid Cooling of Olivine-Rich Chondrules
L. A. Taylor, E. H. Cirlin 		  1448

Cutting the Gordian Knot: Lunar Compositions and Mars-Sized Impactors
S. R. Taylor 		  1449

Micromanipulation of Extraterrestrial Particles
A. Teetsov, J. Bradley 		  1450

Modeling of Pressure Ridge Formation on Compound Pahoehoe Lava Flows
E. Theilig, R. Greeley 		  1451

10BE and 26AL Production from mg, al, si, and O by 600-MEV Protons in Granodiorite Spheres
S. Theis, P. Englert, R. Michel, D. Aylmer, G. F. Herzog, T. H. Kruse, R. K. Moniot, C. Tuniz, A. Jermakian, J. Klein, R. Middleton 		  1452

The Effect of Variable Wavelength Ultraviolet Light on the Production of Oxygen Isotopic Anomalies
M. H. Thiemens, T. Jackson 		  1453

Non-Newtonian Crater Relaxation in Ice
P. J. Thomas, G. Schubert 		  1454

The Role of Alumina Polymorphs as Catalysts for Hydrocarbon Reactions in the Solar Nebula and Early Solar System
K. L. Thomas-Ver Ploeg, F. J. M. Rietmeijer 		  1455

High Resolution Radar Map of the Moon
T. W. Thompson 		  1456

Lunar and Venusian Radar Bright Rings
T. W. Thompson, R. S. Saunders 		  1457

Phyllosilicates in the Mokoia CV3 Carbonaceous Chondrite: Petrographic and Transmission Electron Microscope Observations
K. Tomeoka, P. R. Buseck 		  1458

Core Formation in the Shergottite Parent Body (spb)
A. H. Treiman, J. H. Jones, M. J. Drake 		  1459

Capturing of Hypervelocity Particles
P. Tsou, D. E. Brownlee, A. L. Albee 		  1460

A Fractal Approach to Planetary Spectra
D. L. Turcotte 		  1461

Impact-Induced Devolatization of Murchison Carbonaceous Chondrite
J. A. Tyburczy, B. Frisch, T. J. Ahrens 		  1462

Possible Point Source of Mantle Upwelling, Galileo Regio, Ganymede
J. R. Underwood, A. Woronow, R. Casacchia, M. J. Teeling 		  1463

Fusing Lunar Materials with Microwave Energy. Part II: Melting of a Simulated Glassy Apollo 11 Soil
D. T. Vaniman, T. T. Meek, R. D. Blake 		  1464

Continued Studies of Outer-Belt - CCD Reflectance Spectra
F. Vilas 		  1465

Sulfur Cycle on Venus
V. P. Volkov 		  1466

Cross-Strike on Maxwell Montes, Venus: Evidence for Large-Scale Strike-Slip Faulting
R. W. Vorder Bruegge, J. W. Head, D. B. Campbell 		  1467

ALHA 77005 and on the Chemistry of the Shergotty Parent Body (mars)
H. Wanke, G. Dreibus, E. Jagoutz, H. Palme, B. Spettel, G. Weckwerth 		  1468

Efremovka Fine-Grained Inclusion E14: Comparisons with Allende
D. A. Wark, A. S. Kornacki, W. V. Boynton, A. A. Ulyanov 		  1469

Compositional Contrast Between Martian Regolith and SNC Meteorites: Evidence for Buried Massive Carbonates?
P. H. Warren 		  1470

"new" Nonmare Rocks from Apollo 12 and 17: Still Few Ferroan Anorthosites
P. H. Warren, E. A. Jerde, G. W. Kallemeyn 		  1471

A Nonmagmatic Origin of Group-Iie Iron Meteorites
J. T. Wasson, J. Wang 		  1472

Strain Estimates for Basalt Plains Ridges on Mars, Earth, and the Moon
T. R. Watters, T. A. Maxwell 		  1473

Oblique Impacts: Ejecta Mass and Velocity Distributions
S. J. Weidenschilling, D. R. Davis 		  1474

Barred Olivine Chondrules in Ordinary Chondrules: Petrologic Constraints and Implications
M. K. Weisberg 		  1475

Dynamics of Cometary Showers
P. Weissman, P. Hut 		  1476

Grain Size and Petrographic Analysis of Disaggregated Apollo 15 and 16 Regolith Breccias
S. J. Wentworth, D. S. McKay 		  1477

The Early Stages of Planetesimal Accumulation
G. W. Wetherill, G. R. Stewart 		  1478

The Geology of the Lunar Mare Fecunditatis
J. L. Whitford-Stark 		  1479

Timing of Ancient Extensional Tectonic Features on Mars
R. Wichman, P. H. Schultz 		  1480

Laboratory Shock Emplacement of Nitrogen and Noble Gases Into Basalt
R. C. Wiens, R. O. Pepin 		  1481

Lava-Ice Interactions on Mars
D. E. Wilhelms 		  1482

Relation Between Gullying and Crater Degradation in the Martian Uplands
D. E. Wilhelms, R. J. Baldwin 		  1483

Areas of Gullied Terrain and Possible Volcanic Deposits in the Martian Uplands
D. E. Wilhelms, C. J. Hayden 		  1484

Wind Erosion on Mars: Impairment by Poor Saltation Cloud Development
S. H. Williams, R. Greeley 		  1485

Salt Tectonics on Venus
C. A. Wood, D. L. Amsbury 		  1486

High Temperatures and Chondrule Formation in a Turbulent Shear Zone Beneath the Nebula Surface
J. A. Wood 		  1487

Fusing Lunar Materials with Microwave Energy. Part i: Studies of Doping Media
R. A. Wright, F. H. Cocks, D. T. Vaniman, R. D. Blake, T. T. Meek 		  1488

Burkhala: a New Anomalous Iron Meteorite
N. I. Zaslavskaya, L. F. Migdisova, N. N. Kononkova 		  1489

Adsorption of H2O and CO2 on Mauna Kea Palagonites
A. P. Zent, F. P. Fanale 		  1490

Spatial Resolution and the Geologic Interpretation of Martian Morphology
J. R. Zimbelman 		  1491

Comparisons Between High Resolution Thermal Inertias and Mars Consortium Data for the Elysium and Aeolis Quadrangles of Mars
J. R. Zimbelman, L. A. Leshin 		  1492

Heavy Carbon in Individual Oxide Grains from Murchison Acid Residue Cfoc
E. Zinner, S. Epstein 		  1493

Stratospheric Particle Abundance and Variations Over the Last Decade
M. E. Zolensky, L. Kaczor 		  1494

Oxidation of Iron-Bearing Silicates on Venus Surface
M. Yu. Zolotov 		  1495

Venus Weathering Crust: Structure and Development
M. Yu. Zolotov 		  1496

Nitrates in Martian Soil?
M. Yu. Zolotov, Yu. I. Sidorov 		  1497

On the Asteroidal Component of Cosmic Dust
H. A. Zook, D. S. McKay 		  1498

A Dynamic Model for Ridge Belts on Venus and Constraints on Lithospheric Structure
M. T. Zuber 		  1499

Asteroid Dynamical Families: Mostly Mythical?
J. F. Bell 		  1500

Mineralogical Evolution of Meteorite Parent Bodies
J. F. Bell 		  1501

Neutron Activation Analysis of Iridium and Other Elements (cr, fe, ni, sc, Co) in Individual Cosmic Spherules from the Melt Zone of the Greenland Ice CAP
Ph. Bonte, C. Jehanno, M. Maurette 		  1502

A Test of Solar System Abundance Smoothness
D. S. Burnett, D. S. Woolum, T. M. Benjamin, P. S. Z. Rogers, C. J. Duffy, C. J. Maggiore 		  1503

Ice Lenses on Mars
F. Costard, A. Dollfus 		  1504

Physics of the Martian Soil by Optical Polarimetry and Thermal Measurements
A. Dollfus, M. Deschamps 		  1505

Carbon and Nitrogen Isotopic Variations in the Organic Matter of CM2 Carbonaceous Chondrites
I. Gilmour, I. P. Wright, C. T. Pillinger 		  1506

Progress in Diamond Cell Experiments: Pressures above Three Megabars
K. A. Goettel, W. C. Moss, R. Reichlin, S. Martin 		  1507

Spectral Reflectance Studies of TYCHO Crater: Preliminary Results
B. R. Hawke, P. G. Lucey, J. F. Bell, R. Jaumann, G. Neukum 		  1508

Cosmogenic Helium in Terrestrial Basalts
M. D. Kurz 		  1509

An Improved "fractal" Characterization of Projectile Impact Microcraters. Preliminary Implications to Micrometeorites
M. Maurette, D. E. Passoja, D. Maas, M. Laurence 		  1510

The Size Distributions of Fragments Ejected at a Given Velocity from Impact Craters
J. D. O'Keefe, T. J. Ahrens 		  1511

An Iridium Anomaly in the Middle Jurassic of the Venetian Region, Northern Italy
R. Rocchia, D. Boclet, A. Castellarin, C. Jehanno 		  1512

Collisional Evolution of Rotating Particles: Application to Saturn's Rings
H. Salo 		  1513

Mercury's Magnetic Field Revisited: a New Model
D. J. Stevenson 		  1514

The Uranus-Neptune Dichotomy: the Role of Giant Impacts
D. J. Stevenson 		  1515

Interplanetary Dust: Arguments in Favour of a Late Stage Nebular Origin of the Chondritic Aggregates
C. C. A. H. van der Stap, R. D. Vis, H. Verheul 		  1516

Pioneer Venus Radar Characteristics of the Parquet Terrain
D. L. Bindschadler, J. W. Head 		  1517

Caldera Structure on IO
L. S. Crumpler 		  1518

Cross-Strike Discontinuities in Western Aphrodite Terra, Venus
L. S. Crumpler, J. W. Head, D. B. Campbell 		  1519

Evidence for Large-Scale Horizontal Motions in Northwest Ishtar Terra, Venus
L. S. Crumpler, J. W. Head, D. B. Campbell 		  1520

Pioneer Venus Characteristics of Ovoids on Venus: Preliminary Results
E. R. Stofan, J. W. Head 		  1521

Beta Regio Rift Zone, Venus: Analysis of Arecibo and Venera Data
E. R. Stofan, J. W. Head, D. B. Campbell, S. H. Zisk, A. F. Bogomolov, O. N. Rzhiga, A. T. Basilevsky 		  1522