"That would have redistributed the chemical elements in Earth's crust to a great extent," he said.
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So much Precambrian iron ore was eroded during the transgression that the basal Cambrian rocks can be ores in their own right, for example, in Missouri and Wyoming (Murphy and Ohle, 1968 and Hausel, 1989).
Many of these iron deposits are gold-bearing, some are strongly phosphatic, and others contain associated REE deposits.
The Precambrian–Cambrian boundary saw marine transgression across intensely weathered surfaces, which commonly show extensive alteration and related planation to a degree without parallel in the geological record (Investigation of the distribution of metalliferous ore deposits on the sub-Cambrian surface leads to two conclusions.
Firstly, there was a relatively high abundance of such deposits, and secondly many of these deposits were demonstrably weathered and even enriched before the subsequent peneplanation and transgression.
"The only way you can get shatter cones is when extremely strong shock waves are passing through material. "The only other places you see them on Earth are around nuclear test sites." Other bits of evidence include microscopic, flaky diamonds formed by the passage of shock waves through carbon-rich rocks.
The shock waves also transform tiny mineral crystals into glass.
Other types of gold deposit are exposed on the surface, especially in shear zones, for example, in Wyoming (Laurentia), Saskatchewan (Laurentia), Jordan (Gondwana) and Newfoundland (Avalonia) (Bayley et al., 1973, O’Brien, 2002, Saskatchewan Ministry of Energy and Resources, 2008 and Al-Hwaiti et al., 2010).
The signs of the impact are vague, because most of the crater has eroded.
Geochemical change at the boundary is evident as metal enrichment (Schrödinger and Grotzinger, 2007 and Wille et al., 2008), and specifically Rare Earth Element (REE) enrichment ().