The Preliminary Analysis Of Tectonic Movement Along The Bedding Plane And Its Relationship With Reservoir Formation

In this paper, we take Tertiary of Zhanhua depression (extensional basin),Tertiary of west Qaidam Basin (compressional basin) and Upper Paleozoic of Ordos Basin(compressional basin) as main reaserch areas. Through the cores observation, slices (including fluorescent slices) analysis, rock compression-resilience-break experiments, geological analysis and other methods, we primarily analyze the tectonic movement along the bedding plane and the causes of it. We also primarily study the permeability and fluid migration traces of the sedimentary rocks where the tectonic movement along the bedding plane has happened, obtaining the following understanding:1.In sedimentary rock layer interfaces of Tertiary of Zhanhua depression (extensional basin),the Upper Paleozoic of Ordos Basin (compressional basin) and the Qaidam Basin, (compressional basin), there are a lot of flat,smooth gliding planes. Some have scratches, steps, and some have mirror structure, from which we could tell the direction of the tectonic movements along the bedding plane. These gliding planes prove that the tectonic movements along the bedding plane are widely existed in the layer of sedimentary rock of oil and gas bearing basins.2.In extensional basin, the tectonic movements along the bedding plane are related to the parallel bedding plane elongations of different rocks in process of buring. Buried in the same conditions (same vertical compressive stress conditions), elongations between different rocks are different which result in gliding along the bedding plane.In compressional basins, different parallel bedding plane contraction and rupture strength of rock lead to the tectonic movements along the bedding plane. In the same compressive stress condition, the rock whose contraction is low breaks first.3.The rock interfaces with gliding along the bedding plane have a high permeability between 198×10-3μm2 and 56500×10-3μm2, the rock without gliding along the bedding plane has a permeability between 0.0041×10-3μm2 and 23.3×10-3μm2. SEM and fluorescence data show that on the face of gliding along the bedding plane fluid migrates in a limited migration pathway. the migration pathway has a complex composition and has strong fluorescence. The composition of the migration pathway is complex and its fluorescence is strong.