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1、石油概述AnOverviewofPetroleum1.石油的生成GenesisofPetroleum研究表明,石油的生成至少需要200万年的时间,在现今已发现的油藏中,时间最老的可达到5亿年之久。在地球不断演化的漫长历史过程中,有一些“特殊”时期,如古生代和中生代,大量的植物和动物死亡后,构成其身体的有机物质不断分解,与泥沙或碳酸质沉淀物等物质混合组成沉积层。由于沉积物(sediment)不断地堆积加厚,导致温度和压力上升,随着这种过程的不断进行,沉积层变为沉积岩(sedimentaryrock),进而形成沉积盆地(sediment
2、arybasins),这就为石油的生成提供了基本的地质环境(geologicalenvironment)。StudieshaveshownthatthegenerationofPetroleumneedsatleast200millionyears,andtheoldestoildepositthathasbeenfoundhasahistoryof500millionyears.Therearesome"special"periodintheconstantlyprocessofearth'sevolution,suchasthe
3、PaleozoicandMesozoiceras,whenalargenumberofplantsandanimalsdied.Aftertheirdeath,theorganicsubstancecomposingtheirbodygraduallydecomposed(分解,腐烂),andcomprisedsedimentaryformationtogetherwithsedimentorCarbonic-acidprecipitateandothermaterial.Withthesedimentconstantlypilin
4、gup,thetemperatureandpressureriseaswell.Illuvialhorizongraduallybecamesedimentaryrockastheprocesscontinued,andthusthesedimentarybasinsformed,whichprovidesfundamentalgeologicalenvironmentfortheGenesisofPetroleum.伴随各种地质作用(geologicalprocess),沉积盆地中的沉积物持续不断地堆积。当温度和压力达到一定程度后
5、,沉积物中动植物的有机物质转化为碳氧化合物分子,最终生成石油和天然气。Accompaniedbyavarietyofgeologicalprocess,sedimentsinsedimentarybasinscontinuedtoaccumulation.Whenthetemperatureandpressurereachesa8certaindegree,theorganicmatteoffloraandfaunainthesedimenttranslatedintotheCarbonoxygencompoundmolecules
6、,andfinallyoilandnatgascameintobeing.2.石油的聚集Petroleumaccumulation石油不像水聚集在水库中那样聚集在沉积盆地最初形成的岩石——生油源岩,也就是沉积岩中,而是透过岩石的孔隙,被挤压到压力分布更低的岩石裂缝和孔隙中,直至停留在被完全封闭的储集岩中。储集岩(reservoirrock)是聚集石油的岩石。储集岩形成了储藏石油的地质环境——圈闭构造,它是阻止石油被继续运移的地质构造。石油的这种聚集方式就如同水被一块海绵吸收一样。正因为有了储集岩和圈闭构造,石油才能安静地在地下定居,
7、等待发掘者的到来。Oil,unlikewatergatheringinthereservoir,gathersintheOil-generatingsourcerock,i.e.sedimentaryrock.Instead,itisextrudedintocracksandporesofrockthroughtheporesoftherockwherethedistributionofpressureislower,untilitrestonacompletelyclosedreservoirrock.Thereservoirro
8、ckisarockofoil,anditformsthegeologicalenvironmentofpetroleumstorage--trapstructures,anditisthisgeologicalstructuretha