Venus Volcanism: Initial Analysis from Magellan Data
Abstract
Magellan images confirm that volcanism is widespread and has been fimdamentally important in the formation and evolution of the crust of Venus. High-resolution imaging data reveal evidence for intrusion (dike formation and cryptodomes) and extrusion (a wide range of lava flows). Also observed are thousands of small shield volcanoes, larger edifices up to several hundred kilometers in diameter, massive outpourings of lavas, and local pyroclastic deposits. Although most features are consistent with basaltic compositions, a number of large pancake-like domes are morphologically similar to rhyolite-dacite domes on Earth. Flows and sinuous channels with lengths of many hundreds of kilometers suggest that extremely high effusion rates or very fluid magmas (perhaps komatiites) may be present. Volcanism is evident in various tectonic settings (coronae, linear extensional and compressional zones, mountain belts, upland rises, highland plateaus, and tesserae). Volcanic resurfacing rates appear to be low (less than 2 Km^3/yr) but the significance of dike formation and intrusions, and the mode of crustal formation and loss remain to be established.
Additional Information
© 1991 American Association for the Advancement of Science. Received 22 January 1991; accepted 20 March 1991. We gratefully acknowledge the Magellan Team at JPL, Martin-Marietta, and Hughes for their dedication to obtaining the data. D. Senske prepared the maps of Sif Mons and contributed to the discussion of Western Eistla Regio. K. Roberts prepared the maps of Sacajawea Patera and contributed to the discussion of Sacajawea and Mylitta Fluctus. J. Aubele and E. Slyuta prepared maps of the small shields and contributed to the discussion. B. Klose and B. Pavri contributed to the discussion of the steep-sided domes. D. Bindschadler and E. Stofan contributed to the discussion of the coronae. S. Keddie contributed to the discussion of cryptodomes. P. Fisher, E. Grosfils, A. deCharon, M. Bulmer, A. T. Basilevsky, V. Kryuchkov, and T. Parker contributed to the discussion and review of this paper. Special thanks to S. Yewell, J. Clark, J. Clough, and R. Post for preparation of images and figures. We gratefully acknowledge helpful reviews from J. Garvin and an anonymous reviewer.Additional details
- Eprint ID
- 61808
- DOI
- 10.1126/science.252.5003.276
- Resolver ID
- CaltechAUTHORS:20151104-090823868
- Created
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2015-11-04Created from EPrint's datestamp field
- Updated
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2021-11-10Created from EPrint's last_modified field
- Caltech groups
- Division of Geological and Planetary Sciences