Tessera terrain on Venus: Global characterization from Magellan data

Tessera terrain is characterized by relatively high elevations and complex tectonic patterns; analysis of Venera 15/16 data showed that large (up to thousands of km across) and small (up to hundreds of km across) occurrences of tesserae are widespread and non-randomly distributed and make up about 10-15 percent of the surface of Venus north of approximately 30 deg N. In a previous analysis, we used the Magellan Cycle 1 and 2 data to map the global distribution of tesserae on the basis of the following: (1) complex deformational patterns (two or more trends); (2) relatively high radar backscatter; and (3) relatively high elevation. Here we report on the quantitative aspects of tesserae areal, size, and shape distribution and on the characteristics and distribution of tesserae boundaries. Experiments on volcanic flooding of tessera and implications for tessera presence beneath the plains and analysis of the distribution of impact craters on tesserae and the plains are reported elsewhere.