Note to users. If you're seeing this message, it means that your browser cannot find this page's style/presentation instructions -- or possibly that you are using a browser that does not support current Web standards. Find out more about why this message is appearing, and what you can do to make your experience of our site the best it can be.

Science 9 March 1990:
Vol. 247. no. 4947, pp. 1191 - 1196
DOI: 10.1126/science.247.4947.1191
Prev | Table of Contents | Next

Articles

Venus: A Contrast in Evolution to Earth

William M. Kaula 1

1 Department of Earth and Space Sciences and the Institute of Geophysics and Planetary Physics, University of California, Los Angeles, CA 90024

Of the planets, Venus and Earth are by far the most similar in primary properties, yet they differ markedly in secondary properties. A great impact into Earth is believed to have created its moon and removed its atmosphere; the lack of such an impact into Venus apparently led to a greatly differing atmospheric evolution. The lack of an ocean on Venus prevents the recycling of volatiles and inhibits subduction, so that its crust is probably more voluminous than Earth's, although distorted and quite variable in thickness. Venus's upper mantle appears to be depleted in both volatiles and energy sources because, in addition to the lack of volatile recycling, melts of mantle rocks are more dense than their solid matrix at pressures above 8 gigapascals and hence sink if they occur at depths below 250 kilometers. Appreciable energy sources persist at great depths to sustain the few great mountain complexes. The greatest current problem is reconciling the likelihood of a voluminous crust with indications of considerable strength at shallow depths of 20 to 100 kilometers.


THIS ARTICLE HAS BEEN CITED BY OTHER ARTICLES:
Venus diapirs: Thermal or compositional?.
V.L. Hansen (2003)
Geological Society of America Bulletin 115, 1040-1052
   Abstract »    Full Text »    PDF »
Artemis: Surface expression of a deep mantle plume on Venus.
V. L. Hansen (2002)
Geological Society of America Bulletin 114, 839-848
   Abstract »    Full Text »    PDF »
Venus Reconsidered.
W. M. Kaula (1995)
Science 270, 1460-1464
   Abstract »    PDF »
Global Variations in the Geoid/Topography Admittance of Venus.
M. Simons, M. Simons, B. H. Hager, and S. C. Solomon (1994)
Science 264, 798-803
   Abstract »    PDF »
Hot-Spot Evolution and the Global Tectonics of Venus.
R. J. Phillips, R. J. PHILLIPS, R. E. GRIMM, and M. C. MALIN (1991)
Science 252, 651-658
   Abstract »    PDF »
Fundamental Issues in the Geology and Geophysics of Venus.
S. C. Solomon, S. C. SOLOMON, and J. W. HEAD (1991)
Science 252, 252-260
   Abstract »    PDF »
Deuterium on Venus: Observations From Earth.
C. de Bergh, C. DE BERGH, B. BEZARD, T. OWEN, D. CRISP, J.-P. MAILLARD, and B. L. LUTZ (1991)
Science 251, 547-549
   Abstract »    PDF »
Catching Venus in the Act.
R. A. Kerr and R. A. K. (1990)
Science 249, 742-743
   PDF »
Planetary Fluids.
R. B. Hanson and R. B. Hanson (1990)
Science 248, 281
   PDF »


To Advertise     Find Products

Science. ISSN 0036-8075 (print), 1095-9203 (online)