Dataset Information

Areally Extensive Surface Bedrock Exposures on Mars: Many Are Clastic Rocks, Not Lavas.

ABSTRACT: Areally extensive exposures of intact olivine/pyroxene-enriched rock, as well as feldspar-enriched rock, are found in isolated locations throughout the Martian highlands. The petrogenetic origin(s) of these rock units are not well understood, but some previous studies favored an effusive volcanic origin partly on the basis of distinctive composition and relatively high thermal inertia. Here we show that the regolith development, crater retention, and morphological characteristics for many of these "bedrock plains" are not consistent with competent lavas and reinterpret the high thermal inertia orbital signatures to represent friable materials that are more easily kept free of comminution products through eolian activity. Candidate origins include pyroclastic rocks, impact-generated materials, or detrital sedimentary rocks. Olivine/pyroxene enrichments in bedrock plains relative to surrounding materials could have potentially formed through deflation and preferential removal of plagioclase.

SUBMITTER: Rogers AD

PROVIDER: S-EPMC6310033 | biostudies-literature | 2018 Feb

REPOSITORIES: biostudies-literature

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Areally Extensive Surface Bedrock Exposures on Mars: Many Are Clastic Rocks, Not Lavas.

Rogers A Deanne AD Warner Nicholas H NH Golombek Matthew P MP Head James W JW Cowart Justin C JC

Geophysical research letters 20180220 4

Areally extensive exposures of intact olivine/pyroxene-enriched rock, as well as feldspar-enriched rock, are found in isolated locations throughout the Martian highlands. The petrogenetic origin(s) of these rock units are not well understood, but some previous studies favored an effusive volcanic origin partly on the basis of distinctive composition and relatively high thermal inertia. Here we show that the regolith development, crater retention, and morphological characteristics for many of the ...[more]

PMID: 30598561

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Dataset Information

Areally Extensive Surface Bedrock Exposures on Mars: Many Are Clastic Rocks, Not Lavas.

Publications

Areally Extensive Surface Bedrock Exposures on Mars: Many Are Clastic Rocks, Not Lavas.

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