@rosborne979,
many times they would be exhausting the lines of evidence so that they could sidle into a conclusion where to see life or are they even in a correct spot? As Edgar reported, the oxide and sulphate coatings on rocks, rather than evidences of clay minerals, would lead to a whole different batch of conclusions.
And if you look at the rocks, they only have evidence of episodic weathering in flowing water. SOme ofthe rocks are subangular with only the edges rounded slightly. Thats episodic flooding and seasonal water perhaps. Its like how the grand canyon rocks appear. Water undermines large banks and rock tumble in tye stream and the streamnsflow and then dry up so the rocks are often quite angular.
We are always used to making comparison models and then testing them out.
Lastly, they dont wanna **** up any future science with quick conclusions that fall apart later