The deep structure of Venusian plateau highlands

Details The deep structure of Venusian plateau highlands The deep structure of Venusian plateau highlands

Nov 1994

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1994icar..112...89g&link_type=abstract

Icarus (ISSN 0019-1035), vol. 112, no. 1, p. 89-103

Physics

Geophysics

42

Highlands, Planetary Crusts, Plateaus, Topography, Venus (Planet), Venus Surface, Compensation, Geophysics, Gravity Anomalies, Magellan Project (Nasa), Planetary Geology, Planetary Mantles, Tectonics

Scientific paper

Magellan gravity data confirm that several of the large, tectonically deformed, plateau-like highlands on venus are shallowly compensated, most likely by crustal thickness variations. Apparent depths of isostatic compensation, computed in the spatial domain, range from 30 to 50 km for Alpha, Tellus, Ovda, and Thetis Regiones. Using a two-layer model for isostatic compensation, Alpha, Tellus, and Ovda are best represented as nearly completely compensated in crust that is regionally 20-40 km thick around these highlands, with little contribution from deeper mantle sources. In contrast to these three areas, a stronger regional gravity high associated with Thetis requires a significant upper mantle component to compensation. This is evident in the spectral admittance as a pronounced deep, long-wavelength anomaly. In the two-layer isostatic model, a broad, deeply compensated upland underlies a shallowly compensated central block of Thetis. If this deep component is interpreted as a thermal anomaly, the loci of maximum upwelling agree well with sites of recent extension. The plateau highlands are thus physiographically and isostatically equivalent to terrestrial continents, though probably not compositionally. They also share the record of a long tectonic history. The large regional gravity anomaly of Thetis indicates that active mantle proceses continue even beneath some areas (tessera) thought to be a relic of a former geological regime. The excellent agreement of modeled crustal thicknesses around Alpha, Tellus, and Ovda Regiones suggests that 20-40 km is a representative global value for the plains. Such a crust is thicker than previously estimated and about twice as thick as the expected thickness of crust produced at venusian spreading centers

Affiliated with

Also associated with

No associations

Rating

The deep structure of Venusian plateau highlands does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with The deep structure of Venusian plateau highlands, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The deep structure of Venusian plateau highlands will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1024543