Meter-scale morphology of the north polar region of mars

Kenneth E. Herkenhoff; S. Byrne; P.S. Russell; K.E. Fishbaugh; A. S. McEwen

doi:10.1126/science.1143544

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Meter-scale morphology of the north polar region of mars

Kenneth E. Herkenhoff·S. Byrne·P.S. Russell·K.E. Fishbaugh·A. S. McEwen

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Abstract

Mars' north pole is covered by a dome of layered ice deposits. Detailed (∼30 centimeters per pixel) images of this region were obtained with the High-Resolution Imaging Science Experiment on board the Mars Reconnaissance Orbiter (MRO). Planum Boreum basal unit scarps reveal cross-bedding and show evidence for recent mass wasting, flow, and debris accumulation. The north polar layers themselves are as thin as 10 centimeters but appear to be covered by a dusty veneer in places, which may obscure thinner layers. Repetition of particular layer types implies that quasi-periodic climate changes influenced the stratigraphic sequence in the polar layered deposits, informing models for recent climate variations on Mars.

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Kenneth E. Herkenhoff, S. Byrne, P.S. Russell, K.E. Fishbaugh, A. S. McEwen. 2007. Meter-scale morphology of the north polar region of mars. https://doi.org/10.1126/science.1143544

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