University of Wyoming Researcher, Kevin Chamberlain, has helped disprove a previously wide-held theory of two Precambrian super continents (called Nuna-Columbia and Rodinia) using a technique called “diking,” which examines specific types of layers in rocks called dikes. Chamberlain examined “mafic” dikes in layers of rock, which are dark bands of mineral or rock containing magnesium and iron that form between existing, older rocks. Chamberlain found similar dike swarms (cluster of dikes within the continental crust) in the Southern regions of Siberia and mountain ranges of Wyoming, as well as similar ages of cratons and dike swarms in the two regions. This helped determine when and where the cratons split apart and caused continent reformation, which proved that the Southern region of Siberia and the core of North America where Wyoming’s mountain ranges fall were connected at one point. The findings helped Chamberlain conclude that these regions were connected for about 1.2 billion years, anywhere from 1.9 to 700 million years ago, as one of four or five hypothesized super continent cycles.
The discovery also brought good news to the futures of mining companies. The uncovering of similar dike swarms and craton ages in the two geographic regions reveal that large metal deposits are likely to exist under the younger layers of rock.
Find the article at : https://www.sciencedaily.com/releases/2016/04/160412091348.htm
I didn’t realize how extreme the dike formation process was! “Linear dikes from these igneous events are relatively narrow, roughly 100 meters or less, but can be 1,000 to 1,500 km in length.” I though it was a little strange how much the article referenced the economic value of this researcher’s findings, but once I read at the end of the article that his work was funded by these companies this made sense. I would have liked to know how deep these rock formations are – although clearly they cannot be TOO deep to remain economically feasible to extract.
How does this theory relate to the theory of plate tectonics and Pangea?
A very interesting blog post on more evidence for continental drift. It is interesting to know that my previous post helped Sophia understand her material better. It will be important to see how mining companies go about extracting valuable metals from underneath cratons considering the instability of the Earth’s crust in these locations