孤北地区沙三段物源通道及古地貌恢复

Provenance Channel and Paleogeomorphic Restoration of the Third Member of Shahejie Formation in Gubei Area

摘要: 目前对于孤北地区沙三段认识程度较低，近期的研究表明其具有巨大的勘探开发潜力。而物源作为储层发育的影响因素之一，明确其搬运通道具有重要意义。物源通道是常位于由地表遭受侵蚀形成的古地貌的低势区，如古沟谷地区，其一般顺地层界面附近发育，是源区沉积物向汇区内搬运、堆积的相对地势区。因此识别古沟谷可有效判定物源供给方向及其控制下物源分散体系格局。物源通道的识别主要通过地震剖面，研究区的主要物源通道为古沟谷和断槽。孤北–渤南区域共识别出古沟谷物源通道和断槽物源通道两大类——包含五小类物源通道类型。不同类型物源通道、物源供给方向及供源能力对沉积区作用强弱等方面存在明显差异，需综合刻画此两类物源通道并明确其展布特征，指导储集砂体的预测和分析。

Abstract: At present, the third member of Shahejie formation in Gubei area is in a lower degree of know-ledge, and recent studies show that it has great exploration and development potential. As one of the influencing factors of reservoir development, provenance is of great significance to clarify its transportation channels. The provenance channel is often located in the low potential area of paleogeomorphology formed by surface erosion, such as the ancient gully region, which is generally developed near the stratigraphic interface, and is the relative area where the sediments in the source area are transported and accumulated to the sink area. Therefore, identifying ancient gully can effectively determine the provenance supply direction and the distribution system pattern of the provenance under its control. The identification of provenance channels is mainly through seismic profiles. The main provenance channels in the study area are ancient gullies and fault grooves. The Gubei-Bonan region has identified two major types of provenance channels, namely, the ancient ditch grain source channel and the fault channel source channel—including five types of source channel types. There are obvious differences in different types of provenance channels, provenance supply directions and supply capabilities on sedimentary areas. It is necessary to comprehensively describe these two types of provenance channels and clarify their distribution characteristics to guide the prediction and analysis of reservoir sand bodies.