things about geology that just makes sense

by Ralph MT  Geological map of Puchezh-Katunki impact structure from Holm-Alwmark (2021). Isotope geochemistry provide a key in unraveling the absolute ages of rocks and even impact events in the past. The quest for worldwide search for evidence of impact events that can be temporally correlated to extinction events and major biotic crisis were prompted by the established notion supported by geochemical evidence of a large asteroid impact that ended the Cretaceous period around 66 million years ago and is associated with one of the massive extinction events that has occurred on Earth, also known as the K-T boundary. One example for this quest is the Puchezh-Katunki impact structure which is located in the central part of the East European platform, in the Privolzhsky Federal District of Russia. Its impact structure is well-preserved with an 8–10 km-in diameter central uplift surrounded by an annular depression that is about 40 km in diameter and is presently buried under a ...

Veneto Volcanic Province by Ralph MT Different tectonic settings have its own geochemical signatures that tells a tell-tale sign on the processes that occurred in the geological past. High temperature geochemistry which involves geochemical affinity and geochronology provides a window to these processes. One such example is the Veneto Volcanic Province, which is a Cenozoic intraplate volcanic province located in the Southeastern Alps, Northwest of Italy. The Veneto volcanic province is closely associated with the formation of the Alpine Belts that was formed out from the convergence of the European plate and Adria microplate that initiated about a 100 million years ago.  Geochemical signatures of the subduction event between the European plate and Adriatic microplate have been noted from the presence of calcalkaline to shoshonitic affinities of intrusive bodies and basaltic and andesitic dikes. Calc-alkaline volcanism is expected to be constrained in the tectonic setting of converg...