Cretaceous–Paleogene extinction event Cretaceous–Paleogene extinction event The Cretaceous–Paleogene (K–Pg) extinction event, also known as the Cretaceous–Tertiary (K–T) extinction, was a sudden mass extinction of some three-quarters of the plant and animal species on Earth, approximately 66 million years ago. With the exception of some ectothermic species such as the leatherback sea turtle and crocodiles, no tetrapods weighing more than survived. It marked the end of the Cretaceous period and with it, the entire Mesozoic Era, opening the Cenozoic Era that continues today. In the geologic record, the K–Pg event is marked by a thin layer of sediment called the K–Pg boundary, which can
Gulf Keystone Petroleum is notably one of the largest Super Giant oilfields discovered in the last 50 years. Shaikan was declared a commercial discovery on August 1, 2012 following a five-well appraisal program. Initially independent estimates place the gross oil-in-place (OIP) volume at 13.7 billion barrels (P50) potentially making it one of the largest oilfields discovered in Iraqi Kurdistan. The oilfield covers an area of some , and comprises a series of limestone reservoirs stacked upon each other. These reservoirs encompass a very long period of geological time, from the Cretaceous which ended some 65 million years ago to the Triassic, which began