Crater counting dating
The method has been calibrated using the ages of samples returned from the Moon.
The accuracy of age estimates of geologically young surfaces based on crater counting on Mars has been questioned due to formation of large amounts of secondary craters.
The work, led by geochemist Ken Farley of the California Institute of Technology (Caltech), could not only help in understanding the geologic history of Mars but also aid in the search for evidence of ancient life on the planet.
Many of the experiments carried out by the Mars Science Laboratory (MSL) mission's Curiosity rover were painstakingly planned by NASA scientists more than a decade ago. Keck Foundation Professor of Geochemistry and one of the 29 selected participating scientists, submitted a proposal that outlined a set of techniques similar to those already used for dating rocks on Earth, to determine the age of rocks on Mars.
In this sense, the derived age is a size-dependent Acrater retention [email protected] B the survival time of craters of given size.
It is not quite a formation age in the sense of the lava flow age, but conveys tremendous information about the erosion/deposition/resurfacing environment of Mars.
Q&A: This comes from expat and a few other people: "Is there statistical information about the angle at which incoming rocks have struck, say, the Moon to create craters?
As opposed to you throwing a rock into sand, that's not an explosion.
Experimentally, we expect that craters will start to look elliptical when the impact angles are below about 10°.
The smooth floor of Yellowknife Bay is made up of a fine-grained sedimentary rock, or mudstone, that researchers think was deposited on the bed of an ancient Martian lake.
In March, Curiosity drilled holes into the mudstone and collected powdered rock samples from two locations about three meters apart.