The Gulf of Paria ( ; ) is a shallow (180 m at its deepest) semi-enclosed inland sea located between the island of Trinidad (Republic of Trinidad and Tobago) and the east coast of Venezuela. It separates the two countries by as little as 15 km at its narrowest and 120 km at its widest points. The tides within the Gulf are semi-diurnal in nature with a range of approximately 1m. The Gulf of Paria is considered to be one of the best natural harbors on the Atlantic coast of the Americas. The jurisdiction of the Gulf of Paria is split between Trinidad and Tobago and Venezuela with Trinidad and Tobago having control over approximately (37.7%) and Venezuela the remainder (62.3%). It was originally named the Gulf of the Whale () by Christopher Columbus, but the 19th-century whaling industry eliminated whales from the area and populations have never recovered. Cartographic sources of the late 18th century repeatedly refer to it as the Sad Gulf (). In the north, the Gulf is connected to the Caribbean Sea through the Dragons' Mouths () between the Paria Peninsula of Venezuela and the Chaguaramas Peninsula of Trinidad. In the south, the Gulf is connected to the Atlantic through the Columbus Channel, also known as the Serpent's Mouth (), between the Cedros Peninsula and the Orinoco Delta. Oil and natural gas The Gulf of Paria lies entirely within the broad strike-slip plate boundary zone of the southeastern Caribbean. The structure of the Gulf consists of a complex set of transtensional basins superimposed on a fold-and-thrust belt (Serrania del Interior of eastern Venezuela). The petroleum of Trinidad has been generated by prolific Upper Cretaceous source rocks, time equivalent to the La Luna and Querecual formations in Colombia and Venezuela. These source rocks were then overlain by a thick succession of Paleogene deep-water sediments (shales and deep water sandstones) and shallow marine siliciclastic reservoir rocks. The transpression due to the influence of the Caribbean plate created several sub-basins across the Trinidad area; each having distinctive petroleum systems. The hydrocarbon basins in Trinidad are Southern Basin, Columbus Basin, Carupano Basin, Central Range/Darrien Ridge Basin and the Caroni Basin and Gulf of Paria Pull-apart Basin. The Caroni Basin is a Cenozoic basin bounded to the north by the El Pilar fault zone and the Northern Range fold-thrust belt and to the south by the Central Range fold-thrust belt. Its