DESCRIPTION AND
DATA SHEET

Carmenta Farra
(Pancake Domes)
Eistla Regio, Venus

Among the unusual volcanic features observed on Venus by Magellan are these circular, flat-topped volcanic domes, called pancake domes. The largest of the domes in this scene is 65 kilometers across and roughly 1 kilometer high. This group of pancake domes is called Carmenta Farra.

A small crater can be found near the center of each dome. This may be the source vent for the extrusion. The center of the largest dome appears to be depressed below the elevation of the margin of the dome. Although the volcano may have once had a flat top, the weight of the volcano pushes down on the crust. The resulting collapse produces the observed depression in the center of the crater.

Although the composition of the these domes is not known, their unusual morphology suggests that they may have a different composition than shield volcanos (like Kunapipi) on Venus. The unusual thickness of these flows indicates they are stickier or more viscous than ordinary basalt. On Earth, thicker lava flows, such as those found at Mono Craters, are usually associated with lavas richer in silica, such as dacite or rhyolite. Whether this is true on Venus as well is not known. These domes could also be explained by basalt erupting at unusually slow rates.

DATA SHEET (Top)

Location:
    13.0 N, 8.0 E
Quadrangle:
    C1-MIDR 15N009
Mission:
    Magellan
Image Resolution
    243 meters/pixel
Image Width:
    150 kilometers
Vertical Exaggeration:
     ~6 × Normal
Convergence Angle:
    20°