摘要
Lots of hydrocarbon inclusions and bitumen have been measured in 90 sandstone samples from the Lower Cretaceous of Shaya uplift,Tarim Basin,and the evidence from these measurements can be used to trace the hydrocarbon migration and accumulation history of the basin.Four types of inclusions were determined in fluorescence observation,i.e.gas-liquid biphase oil inclusions,pure gas inclusions,oil-asphalt inclusions and aqueous inclusions.According to fluorescence properties(fluorescent colors,λmax and QF535) of the oil inclusion and combined with the employment of homogenization temperature of aqueous inclusions projected on a burial history diagram,three oil charging events were determined,and they took place in 12-5 Ma,5-2 Ma and 2-0 Ma,respectively.By the fluorescence spectral comparison of the oil inclusion with the crude oil from oil-prone source beds,it could be concluded that the first and the second charging oils originated from terrigeneous source rocks while the third charging oil was derived from marine ones.The marine oil is characterized by a lower maturity and later charging time compared with the continental oil.Its hydrocarbon accumulation occurred mainly during the middle-late Himalayan period,and is characterized by continuous and rapid charging.