Seismic Description of Deep Strike-Slip Fault Damage Zone by Steerable Pyramid Method in the Sichuan Basin, China

Abstract

Large quantities of gas resources have been found in the Paleo-Mesozoic carbonate rocks in the Sichuan Basin. However, many wells cannot obtain high production in deep low porosity-permeability reservoirs. For this contribution, we provide a steerable pyramid method for identifying the fault damage zone in the Kaijiang–Liangping platform margin, which is infeasible by conventional seismic methods. The results show that steerable pyramid processing could enhance the seismic fault imaging and a series of NW-trending strike-slip faults are found along the trend of the carbonate platform margin. The steerable pyramid attribute presents distinct vertical and horizontal boundaries of the fault damage zone, and heterogeneous intensity of an un-through-going damage zone. The width of the fault damage zone is generally varied in the range of 100–500 m, and could be increased to more than 1000 m in the fault overlap zone, intersection area, and fault tips. Further, the fault damage zone plays a constructive role in the high gas production in the deep tight carbonate reservoir. The results suggest the steerable pyramid method is favorable for identifying the weak strike-slip faults and their damage zone. The width of the fault damage zone is closely related to fault displacement, and the much wider damage zone is generally influenced by the fault overlapping and interaction. The fractured reservoirs in the fault damage zone could be a new favorable exploitation domain in the Sichuan Basin.

Impact of the Regional Pai-Khoi-Altai Strike-Slip Zone on the Localization of Hydrocarbon Fields in Pre-Jurassic Units of West Siberia

“…Seismic section data have been applied to verify the identified tectonic elements and to confirm the configuration of the regional Pai-Khoi-Altai strikeslip zone. This direction using specially designed seismic attributes seems useful for this purpose [68,69]. In the future, it is planned to use the steerable pyramid attribute [67] for identifying the weak strike-slip faults and to test the innovate approach presented in papers [70,71] with a detailed assessment of pressure and direction of fluid migration.…”

Coalbed Methane Reservoir Parameter Prediction and Sweet-Spot Comprehensive Evaluation Based on 3D Seismic Exploration: A Case Study in Western Guizhou Province, China

“…The Middle Permian Qixia Maokou Formation, the Lower Triassic Yongningzhen Formation, and the middle-upper member of the Middle Triassic Guanling Formation in the region are all soluble rocks, with many fissured caves and strong water content, which are essential aquifers. The Emeishan Basalt Formation, the Longtan Formation of the Upper Permian, and the Feixianguan Formation of the Lower Triassic are mostly argillaceous siltstone and silty mudstone with weak water content and permeability, which are the relative water-resisting layer between the above aquifers, as shown in Table 1 [17]. The overlying aquifer of coal measures strata is limestone karst water of the Yongningzhen Formation, and the underlying aquifer is limestone karst water of the The Middle Permian Qixia Maokou Formation, the Lower Triassic Yongningzhen Formation, and the middle-upper member of the Middle Triassic Guanling Formation in the region are all soluble rocks, with many fissured caves and strong water content, which are essential aquifers.…”

“…The overlying aquifer of coal measures strata is limestone karst water of the Yongningzhen Formation, and the underlying aquifer is limestone karst water of the The Middle Permian Qixia Maokou Formation, the Lower Triassic Yongningzhen Formation, and the middle-upper member of the Middle Triassic Guanling Formation in the region are all soluble rocks, with many fissured caves and strong water content, which are essential aquifers. The Emeishan Basalt Formation, the Longtan Formation of the Upper Permian, and the Feixianguan Formation of the Lower Triassic are mostly argillaceous siltstone and silty mudstone with weak water content and permeability, which are the relative water-resisting layer between the above aquifers, as shown in Table 1 [17]. The overlying aquifer of coal measures strata is limestone karst water of the Yongningzhen Formation, and the underlying aquifer is limestone karst water of the Maokou-Qixia Formation (Figure 2), which has large water storage space and strong water content, but it is far away from the coal seam and is blocked by the relative water-resisting layer of the Feixianguan Formation and the Emeishan basalt, which is poor in coal seam replenishment and beneficial to CBM preservation.…”