全球碳酸盐岩地层-岩性大油气田分布特征及其控制因素

碳酸盐岩地层-岩性大油气田是一种重要的油气田类型,勘探已经证实其在全球范围内有着大量的油气资源及油气产量.通过对全球94个碳酸盐岩地层-岩性大油气田的区域展布、层系分布、圈闭类型、储层埋深及储量规模等参数的分析,探讨了其分布的主控因素.这类油气田主要分布于北美、中东和中亚地区,其中北美含油气域的油气最为富集,主要富集层...

Distribution characteristics and controlling factors of global giant carbonate stratigraphic-lithologic oil and gas fields

Giant carbonate stratigraphic-lithologic oil and gas field is an important type of oil and gas field in the world. It has been proved to be rich in oil and gas resources and production. Ninety-four carbonate stratigraphiclithologic oil and gas fields were theoretically analyzed, including their geographical distribution, strata distribution, trap types, buried depth and reserve scale of reservoirs,and the main controlling factors of their distribution were discussed. Such oil and gas fields are mainly distributed in the North America, Middle East and Central Asia, among which North America has the most abundant oil and gas,and the oil and gas resources of carbonate reservoirs are mainly accumulated in the Ordovician, Carboniferous, Paleogene and Neogene. The traps can be classified as biological reef, grain beach, diagenetic trap, unconformity and weathering crust. The reservoir burial depth of these oil and gas fields is generally less than 5 000 m,and the oil and gas fields with reservoir burial depth of more than 5 000 m account for only 6.4%. The effects of the following five key factors on the formation and distribution of giant carbonate stratigraphic-lithologic oil and gas fields were discussed:(1) The stable and confined shallow water environment and mid-low latitude are conducive for the generation and preservation of organic matter.(2) Tectonic movement not only increases the reservoir spaces by producing a large number of faults and fracture zones, but also promotes the migration and accumulation of hydrocarbon(usually matching with the hydrocarbon generation stage), and provides a favorable background for paleo-karstification(. 3) Diagenesis such as paleo-karst improves reservoir performance.(4) Evaporite plays an important role in sealing oil and gas.(5) Trap finalization time and hydrocarbon generation and expulsion time of source rocks need to achieve a good matching relationship in time and space.