their original state. The excavation is conducted to gain raw materials that lead to the creation of ... records as inconclusive. The broader climatic history can be retrieved from the fossil, geological ... Jennifer C. McElwain, "Fossil Plant Stomata Indicate Decreasing Atmospheric CO 2 Prior to the
. Subsequent geological processes have deformed the crater into the current smaller oval shape. Sudbury ... (3 miles) diameter asteroid which excavated a crater originally about 100 km (62 mi) wide although ... headlines worldwide when scientists announced that it contained evidence for microscopic fossils of Martian
, along with thousands of other meteorites, in Johnson Space Center's Meteorite Processing Laboratory ... , excavating and ejecting pieces of the rock with enough force to escape the planet. This particular ... found evidence for fossil life. The pancake shape and layered mineral rims of the tiny carbonate