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- MAGELLAN PROJECT OFFICE
-
- P-38173
- 5/01/91
-
-
- This image, centered at 21.5 degrees north, 359.5 degrees east
- is part of an F-MIDR (Full-resolution Mosaicked Image Data Record)
- covering Magellan orbits 492-523. This is a close look at Gula
- Mons, a shield volcano 4 kilometers (13100 feet) in height in
- northwestern Eistla Regio on Venus. This type of volcanism is
- similar to that of the Hawaiian islands in that it is thought have
- resulted from hot material rising from the interior and heating the
- crust. Both volcanoes formed from hot, fluid lava which erupted
- non-explosively. The radar-bright area consists of both the summit
- (circular southwestern part) and radial troughs and scarps trending
- to the northeast down the slope of Gula Mons. Evidence of regional
- expansion of the crust is expressed in this area by the radial
- troughs or graben and a larger scale fracture complex which trends
- southeast from the bottom right corner of the image. The very thin
- lineations which extend outward from the summit before bending
- southward are thought to be the surface expression of a dike system
- (planes of solidified molten rock within bedrock). The dikes
- formed between intermittent outflows of lava which descend from the
- summit of Gula Mons. This is apparent from the observation that
- some dikes cut the flows while others are covered by them.
-
-
- Jet Propulsion Laboratory
- California Institute of Technology
- National Aeronautics and Space Administration
- Pasadena, Calif. 91109
-