Jacobsville Formation Case Study

The Jacobsville Formation is the earliest formation of the Cambrian Period. Jacobsville Sandstone has a distinguishing characteristic about its deposition that sets it apart from the other formations in the Paleozoic Era. Jacobsville Sandstone is a stream and lake deposit unlike most of the other deposits which were marine sediment deposits. The sandstone is also uniquely red with light coloured marks throughout it which is caused by chemical leaching transversely throughout the bedding planes. Jacobsville Sandstone became very popular with masonry workers because not only is it strong and durable, but it has a well-sorted grain size of sand and its friable structure made it permissible to be crafted into decorative pieces. The thickness of the Jacobsville Sandstone ranges from 5 to over 15,000 feet total. The location of the sandstone is on the Keweenaw Peninsula to the east of the Keweenaw Fault line. This rock is found along the shoreline of Lake Superior in both Michigan and Ontario but many stratigraphers believe that the Jacobsville stretches out under a good deal of Lake Superior as well. Many geologists believe that the sandstone was …show more content…
Being the case with these inter-lying planes, they are highlighted by weathering which has made them appear quite prominent. Sandstones of the massive form usually show one of two forms of lamination; horizontal or cross stratification. In the case of the Jacobsville Sandstone, horizontal is more dominant where as the cross stratification appears more in freshly exposed vertical cliffs. Evidence that the Jacobsville Sandstone formed in a lacustrine environment versus a lenticular environment emerges from the distribution of substantial sandstone facies that were separated from an originating area. This particular feature is more common amongst lacustrine environments that belong to an intermountain