The Costa Rica Seismogenesis Project (CRISP) (IODP Expedition 334) was carried out on the continental margin slope apron in the Costa Rica subduction zone in Central America during March 13 to April 13, 2011. The primary scientific goals of this expedition are to understand the processes that control nucleation and seismic rupture of large earthquakes at erosion-controlled subduction zone. During one month drilling, onboard totally 1492.88 meters long cores were obtained at four sites and eight holes. Tephra layers with ages ranging from Miocene to present were indentified. Rock variation characteristic of sediments and basement rocks were preliminary defined and basalt from the oceanic Cocos ridge basement was recovered.