在松辽梨树、鄂尔多斯、川西、苏北天长、塔北雅克拉等地区,应用色谱-质谱(GC-MS)、紫外吸收光谱(UV)、全扫描荧光(TSF)等方法对浅表微迹烃(小于10-6)进行了测定,证实地下油气源确实存在垂向微运移,并在其上方形成分散场(晕)的晕-源关系,即使是深逾5 000 m具严密盖层的油气藏也不例外.针对目前油气化探基础原理研究比较薄弱的状况,对油气化探基础原理的研究,应从深部地球化学场的观测入手,结合精细的地震地质资料追溯烃类微渗漏的形迹脉络,印证不同的机理假设;同时,还应重视地下油气微渗漏的动态观测,加强组构地球化学场及其异常成因的研究,加快进行有关机理的模拟实验.
GC-MS,UV and TSF have been used to measure traces of hydrocarbons (<10~(-6))in shallow and surface layers in various areas, such as Lishu of Songliao, Ordos, western Sichuan, Tianchang of Northern Jiangsu and Yakela of Northern Tarim. Vertical micro-migrations of hydrocarbons from subsurface sources have thus been proved, which would result in halo-source relationship of dispersion haloes over the sources. There will be no exception even if the reservoirs are buried at a depth of over 5?000?m and there are tight seals. Presently, study of the basic principles of geochemical exploration is relatively weak. In view of this situation, we should begin with the observation of geochemical fields at depth, and determine the traces of micro-percolation of hydrocarbons in combination with fine seismic and geologic data, so as to verify different mechanism hypotheses. At the same time, we should also pay attention to dynamic observation of subsurface hydrocarbon micro-percolation, strengthen study of fabric geochemical field and genesis of geochemical anomalies, and speed up the simulation tests of relevant mechanisms.
Oil & Gas Geology
geochemical field at depth