Ah, so we explored Proterozoic sedimentary rocks today, catching a glimpse into the past before advanced life colonized the earth. These rocks show us how the pre-Cambrian earth was extreme in environments and climate. Vast colonies of stromatolites are preserved in some of the units as well as evidence for tropical glaciation. Can someone say Snowball Earth?
The sandwiching of glacial sediments between thick carbonate units indicates that there was extensive glaciation at low latitudes. We finally got to see dropstones: clasts that drop through the water column from an ice block and then make a depression in the fine clays. It has been the joke answer for the extent of the Stretch, so it was satisfying to finally see them for real.
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