Paleontology and geology

Manitoba was above sea level during the Triassic, and deposition was restricted to river valleys, lakes, and lowlands. Any rocks deposited during this period have been buried below the surface or eroded away, with one exception. In the Middle to Late Triassic, a meteorite hit central Manitoba, shattering and breaking up the Precambrian and Paleozoic rocks at the surface. They were then re-deposited in layers of broken pieces and fragments, a rock type called breccia. Until recently, this impact was thought to be Permian, and the re-deposited rocks are mapped as Permian here and on many maps. Other maps may show these deposits as Triassic.