A revised surface age for the North Polar Layered Deposits of Mars

作者：Landis Margaret E^*; Byrne Shane; Daubar Ingrid J; Herkenhoff Kenneth E; Dundas Colin M

来源：Geophysical Research Letters, 2016, 43(7): 3060-3068.

DOI：10.1002/2016GL068434

The North Polar Layered Deposits (NPLD) of Mars contain a complex stratigraphy that has been suggested to retain a record of past eccentricity- and obliquity-forced climate changes. The surface accumulation rate in the current climate can be constrained by the crater retention age. We scale NPLD crater diameters to account for icy target strength and compare surface age using a new production function for recent small impacts on Mars to the previously used model of Hartmann (2005). Our results indicate that ice is accumulating in these craters several times faster than previously thought, with a 100m diameter crater being completely infilled within centuries. Craters appear to have a diameter-dependent lifetime, but the data also permit a complete resurfacing of the NPLD at similar to 1.5 ka.

• 出版日期2016-4-16