Open AccessThe Martian Grid System, Continental Blocks and Continental Drift
Author(s) -
Wells R. A.
Publication year - 1969
Publication title -
geophysical journal of the royal astronomical society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.302
H-Index - 168
eISSN - 1365-246X
pISSN - 0016-8009
DOI - 10.1111/j.1365-246x.1969.tb00266.x
Subject(s) - geology , martian , lineament , mars exploration program , mantle convection , geophysics , plate tectonics , tectonics , mantle (geology) , paleontology , lithosphere , astrobiology , physics
Summary Mars possesses two grid systems—a diagonal grid made up of lineaments trending approximately NW‐SE and NE‐SW, and a meridian‐latitude grid composed of lineaments trending approximately N‐S and E‐W. The distribution of angles between the two families of lineament planes in the diagonal grid implies the existence of a 4‐cell asymmetric convection pattern within the Martian mantle. The convection pattern readily explains the distribution of the major dark features, considered to be elevated continental blocks, by a continental drift hypothesis. The equatorial maria are elevated regions composed of E‐W overthrust structures, while Mare Acidalium, the only major dark feature in the northern hemisphere, is a ridge‐and‐trough system comparable to a terrestrial oceanic rise. The Martian maria bear structural resemblances to the lunar highlands and the Martian deserts are similar to the lunar maria. Mars has undergone extensive tectonic development over a geological time‐scale.