Multiple sclerosis (MS) is an unpredictable, often disabling disease of the central nervous system that disrupts the flow of information within the brain, and between the brain and body.
The Laramide orogeny was a period of mountain building in western North America, which started in the Late Cretaceous, 70 to 80 million years ago, and ended 35 to 55 million years ago. The exact duration and ages of beginning and end of the orogeny are in dispute.welve kilometers of structural relief between basins and adjacent uplifts is not uncommon. The basins contain several thousand meters of Paleozoic and Mesozoic sedimentary rocks that predate the Laramide orogeny. As much as 5000 m of Cretaceous and Cenozoic sediments filled these orogenically defined basins.
The Ordovician Period started at a major extinction event called the CambrianâOrdovician extinction events about 485.4 Â± 1.9 Mya (million years ago), and lasted for about 42 million years. It ended with the OrdovicianâSilurian extinction event, about 443.8 Â± 1.5 Mya (ICS, 2004) that wiped out 60% of marine genera.