Caribbean Plate 1843 in this region are possibly megathrust earthquakes. Along the geologically complex southern boundary, the Caribbean Plate interacts with the South American Plate forming Barbados, Trinidad and Tobago (all on the Caribbean Plate), and islands off the coast of Venezuela (including the Leeward Antilles) and Colombia. This boundary is in part the result of transform faulting along with thrust faulting and some subduction. The rich Venezuelan petroleum fields possibly result from this complex plate interaction. The Caribbean plate is moving eastward about 22 millimeters per year in relation to the South American plate. In Venezuela much of the movement between
Coast Guard Island Naval Engineering Support Unit Alameda (NESU Alameda were also located on the island until those units were decommissioned in 2013. The functions and capabilities of the units remain as departments within Base Alameda. The facilities on Coast Guard Island also include an industrial service center, enlisted barracks, a medical and dental clinic, and public works facilities to service the island. Originally known as Government Island, this artificial island was formed in 1913 by the dredging project that extended the Oakland Estuary to San Leandro Bay. The Coast Guard first came to the island in 1926 when it established "Base 11"