Becquerel (Martian crater)

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Becquerel
Planet Mars
Region Arabia Terra
Coordinates 22°06′N 352°00′E / 22.1°N 352.0°E / 22.1; 352.0Coordinates: 22°06′N 352°00′E / 22.1°N 352.0°E / 22.1; 352.0
Diameter 167 km
Eponym Antoine H. Becquerel

Becquerel is a 167 km-diameter crater at 22.1°N, 352.0°E on Mars, in Arabia Terra. It is named after Antoine H. Becquerel.

Photographs by the Mars Global Surveyor revealed layered sedimentary rocks in the crater.[1] The layers appear to be only a few meters thick and show little variations in thickness. Recent studies with HiRISE have determined the exact thickness of the layers. The 66 layers measured showed one group of layers to average 3.6 metres (12 ft) and another group to average 36 metres (118 ft) in thickness.[2] Patterns like this are usually produced on Earth through the effects of water; volcanic deposits would not produce ash or laval flows of such regular thickness and in any event there are no nearby volcanic vents.[3]

There are cyclic variations in the thickness of the exposed sedimentary layers, possibly indicating cyclic variations in environmental conditions while the sediment was being laid down.[4] Most of the layers are parallel to each other, suggesting they formed by vertical settling, but a few are cross-bedded, indicating that at the time that the layers were deposited the sediment was transported along the ground surface by wind or water.[5] The sedimentary material appears to be easily eroded and active wind erosion may be continuing to the current day.[6]

Layers in the Martian crater Becquerel

References[edit]

  1. ^ Mars Exploration: Multimedia
  2. ^ Lewis, K. et al. 2008. Quasi-Periodic Bedding in the Sedimentary Rock Record of Mars. Science. 322:1532-1535
  3. ^ HiRISE | Lots of Layering in Becquerel (PSP_003656_2015)
  4. ^ Grotzinger, J. and R. Milliken (eds.) 2012. Sedimentary Geology of Mars. SEPM
  5. ^ Layers in Becquerel Crater, Mars | Clipmarks
  6. ^ Mars Odyssey Mission THEMIS: Feature Image: Becquerel Crater Deposit (Released 28 May 2002)
  7. ^ http://hirise.lpl.arizona.edu/PSP_004078_2015

See also[edit]