东北极陆架区沉积盆地分布与油气资源潜力

Sedimentary Basins in Eastern Arctic Shelf and Their Petroleum Potential

东北极陆架是世界上最宽广的陆架之一,包括巴伦支海、喀拉海、拉普捷夫海、东西伯利亚海、楚科奇海等。受自然条件限制,除巴伦支海外,总体勘探程度很低,甚至连许多盆地的边界尚不清楚。本文对东北极地区沉积盆地的分布进行修编,并对其油气资源潜力进行综述。巴伦支海域,气候条件相对较好,勘探程度也较高,在东巴伦支盆地已发现油气田,并已在开发。据USGS的评价,东巴伦支海盆地技术可采的待发现资源量均值约为104×10^8 t油当量,包括近15×10^8 t原油、10.8×10^（12）m^3天然气和2.8×10^8 t凝析油,主要分布于南巴伦支坳陷和北巴伦支坳陷。拉普捷夫海域,勘探程度低,主体为始于白垩纪的拉普捷夫裂谷系统,据USGS的评价结果,均值为4.2×10^8 t原油,9127×10^8 m^3天然气和1.2×10^8 t凝析油,西拉普捷夫地堑潜力最大。东西伯利亚-楚科奇海域盆地,勘探程度低,主体包括大型南楚科奇-霍普盆地和维尔基茨基-北楚科奇盆地,沉积厚度巨大,主要沉积特征与阿拉斯加北坡盆地可对比,推测可能具有很大的油气资源潜力。

Continental shelf in the eastern Arctic, including Barents Sea, Kara Sea, Laptev Sea, East Siberian Sea and Chukchi Sea, is one of widest in the world. It has only been explored poorly except the Barents Sea, even do not clear for the border of basins, due to the rigorous natural conditions. The sedimentary map in the Eastern Arctic shelf was compiled in the paper, based on all data been collected. It is better climatic condition in the Barents Sea, where has been explored much better, and oil and gas been exploited. USGS estimated the mean undiscovered oil and gas in eastern Barents Basin is about 104 ×10^8 t oil equivalent, including 15 ×10^8 t of crude oil, 10. 8 × 10^12 m^3 of natural gas and 2. 8 ×10^8 t of natural gas liquids, of which main distribute in South Barents Depression and North Barents Depression. Only a little exploration has been executed in the Laptev Sea, which is characterized by Laptev Rift System that began since Cretaceous. According to the USGS assessment, mean undiscovered conventional, technically recoverable petroleum resources in Laptev Sea area is 4.2 ×10^8 t of crude oil, 9127 × 108 m^3 of natural gas, and 1.2 × 10^8 t of natural gas liquids. The greatest volume of undiscovered petroleum is estimated to be in the West Laptev Graben. It is quite lower for the degree of exploration in East Siberian Sea and Chukchi Sea, where including South Chukchii-Hope Basin and Vil＇kitskii-North Chukchi Basin. Based on the comparison with North Slope Basin which is most important petroleum producing area in USA, the East Siberian Sea and Chukchi Sea area should be a very good petroleum potential area.