反演的盆地热史恢复方法与相关问题

INVERSION OF THERMAL HISTORY RECONSTRUCTION IN SEDIMENTARY BASIN AND ITS RELATED PROBLEMS

陈刚 赵重远 李丕龙 任战利 阎汉杰 刘爱永

Chen Gang Zhao Zhongyuan Li Pilong Ren Zhanli Yan Hanjie Liu Aiyong

同一盆地不同深度的镜质体反射率()是盆地所受热流密度变化的反映。因此,可通过建立盆地的古热流、古地温及镜质体反射率模型来反映盆地演化历史。但是,在多旋回盆地中存在多解性及不可逆性。所以,在用进行盆地反演时,应从原始盆地恢复入手,最大限度地挖掘可靠的资料;为了克服的不可逆性及可掩盖性,可将lg-剖面进行分段综合解释,对于被不整合分隔的沉积层,分段求取平均值作为该段的值,对于突变的lg-曲线,则应注意局部火山活动的影响,剔除异常值;另外,盆缘露头及浅埋区的资料则主要用于说明盆地演化早期的古地温场特征。

Vitrinite reflectance, also abbreviated to , in various depth of same sedimentary basin is a reflector of thermal current density changes experienced by the basin. Therefore, the evolutional history of a basin can be reflected by reconstructing ancient thermal current, paleo-ground temperature and a model in the basin. However, can be explained in several ways for multi-cycle basins and with inconvertibility, the reconstruction of a prototype basin would be started at the first and try your best to get as much reliable information about as possible when you conduct basin inversion with . In order to overcome inconvertible and coverable feature of , Lg- section can be explained segment by segment to gain average value of as that segment value in terms of the sedimentary stratum separated by unconformity. As for abrupt change Lg- curve, attention should be paid to effects of local volcanic activities and abnormal value should be picked out. Moreover . Information about basin outcrops and shallow buried areas is mainly applied to explain features of paleo-ground temperature in the early stage of the basin evolution.

10.11743/ogg20020408