Premium
Volcanism in the cratered terrain hemisphere of Mars
Author(s) -
Greeley Ronald,
Spudis Paul D.
Publication year - 1978
Publication title -
geophysical research letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.007
H-Index - 273
eISSN - 1944-8007
pISSN - 0094-8276
DOI - 10.1029/gl005i006p00453
Subject(s) - geology , volcanism , mars exploration program , impact crater , volcano , shield volcano , martian , earth science , lava , southern hemisphere , geochemistry , geomorphology , astrobiology , paleontology , tectonics , physics , climatology
Viking Orbiter photography has revealed the importance of volcanism in the geologic evolution of the cratered terrain hemisphere (generally in the southern hemisphere) of Mars. Volcanic units in this region are classified morphologically into four major units: 1) Patera, comprising 2.37 × 10 5 km² (0.3% of the cratered terrain hemisphere), are large, low profile volcanic structures; some appear to be older shield volcanoes, others apparently represent a unique style of volcanism; 2) “Plains” volcanics occupy 2.3 × 10 6 km² (2.9% of hemisphere) and represent low volume eruptions that formed cones, low shields and other small scale structures; 3) flood volcanics (3.7 × 10 6 km²; 4.7% of hemisphere) are produced by high volume eruptions, post‐date the older and more degraded plateau plains, and occur mostly as basin‐fill materials; and 4) Plateau plains (28.5 × 10 6 km²; 36% of hemisphere), the martian intercrater plains, contain many wrinkle ridges and floor‐fractured craters. The results of this study suggest volcanic processes, as well as erosional processes have been important in the obliteration of small (less than 10km) craters on Mars and that volcanic products may constitute a significant fraction (up to 44%) of the surface rocks in the cratered terrain.