处于主动大陆边缘的巴兰三角洲地区,在构造格局上具有南北分带的特征,其北部发育挤压应力作用下的NE—SW向叠瓦状逆冲推覆构造,中部发育拉张应力作用下的NE向生长断层及其控制下的滚动背斜,南部为压扭作用下早期生长断层发生反转而形成的反转构造.针对北部挤压应力区收缩量大于中部拉张应力区伸展量这一现象无法用理想的被动大陆边缘三角洲体模型来解释的情况,现结合区域构造背景、研究区应力特征及构造恢复结果的分析认为,巽他古陆、菲律宾板块、印澳板块及欧亚板块推挤作用产生的区域压应力的远距离效应与三角洲发育过程中重力驱动的综合作用,是产生该现象的主要原因.

Neogene Baram Delta is located in the northwest Borneo, which is characterized by different structural styles in the northern, the middle and the southern parts respectively, owing to being on the active continental margin. Affected on compression stress, NE-SW striking imbricate thrusts develop in the northern part. Influenced by extension stress, NE striking growth faults and associated rollover anticlines develop in the middle part while the inversion structures generated by compresso-shearing develop in the southern part. It has been confused by the fact why the total shortening amount in the compression area (i.e. the northern part) is greater than the total stretching amount in extension area (i.e. the middle part) , which has been unable to be explained by the ideal model of delta system in the passive margin. Based on the regional tectonic setting and basin stress analysis and the structural restoration, it is shown that accompanied with far-field regional compression that rises from pushing by Philippine Plate, Indo-Australian Plate and Eurasia Plate, the gravitational drive during delta growing has resulted in the comprehensive process, which is regarded as the reason.