Spatial Characteristics and Controlling Factors of the Strike‐slip Fault Zones in the Northern Slope of Tazhong Uplift, Tarim Basin: Insight from 3D Seismic Data

Abstract

The detailed characteristics of the Paleozoic strike-slip fault zones developed in the northern slope of Tazhong uplift are closely related to hydrocarbon explorations. In this study, five major strike-slip fault zones that cut through the Cambrian-Middle Devonian units are identified, by using 3D seismic data. Each of the strike-slip fault zones is characterized by two styles of deformation, namely deeper strike-slip faults and shallower en-echelon faults. By counting the reverse separation of the horizon along the deeper faults, activity intensity on the deeper strike-slip faults in the south is stronger than that on the northern ones. The angle between the strike of the shallower en-echelon normal faults and the principal displacement zone (PDZ) below them is likely to have a tendency to decrease slightly from the south to the north, which may indicate that activity intensity on the shallower southern en-echelon faults is stronger than that on the northern ones. Comparing the reverse separation along the deeper faults and the fault throw of the shallower faults, activity intensity of the Fault zone S1 is similar across different layers, while the activity intensity of the southern faults is larger than that of the northern ones. It is obvious that both the activity intensity of the same layer in different fault zones and different layers in the same fault zone have a macro characteristic in that the southern faults show stronger activity intensity than the northern ones. The Late Ordovician dé collement layer developed in the Tazhong area and the peripheral tectonic events of the Tarim Basin have been considered two main factors in the differential deformation characteristics of the strike-slip fault zones in the northern slope of Tazhong uplift. They controlled the differences in the multi-level and multi-stage deformations of the strike-slip faults, respectively. In particular, peripheral tectonic events of the Tarim Basin were the dynamic source of the formatting and evolution of the strike-slip fault zones, and good candidates to accommodate the differential activity intensity of these faults.

A New Growth Model of Fault Attributes in a Strike‐Slip Fault System in the Tarim Basin

“…4). The flower structure, the abrupt alternation of fault wall, etc., are indicators for strike-slip fault identifications (Wu et al, 2016;Han et al, 2020). On the structural maps using seismic interpretation, we can measure L and orientation to obtain fault geometry and kinematic analysis.…”

“…On the structural maps using seismic interpretation, we can measure L and orientation to obtain fault geometry and kinematic analysis. The offset of the structures, stratigraphy or microfacies, or the seismic attributes in time-slices were used to identify the horizontal S of two fault planes (Wu et al, 2016;Han et al, 2020). However, it is difficult to obtain an accurate horizontal displacement and enough horizontal components of the displacement data along the strike-slip faults in the subsurface.…”

Vertical Differential Structural Deformation of the Main Strike‐slip Fault Zones in the Shunbei Area, Central Tarim Basin: Structural Characteristics, Deformation Mechanisms, and Hydrocarbon Accumulation Significance

“…Studies have shown that deep sections of these SSFZs are characterized by steep strike-slip faults and flower structures, upon which en echelon normal faults or grabens are superimposed (Han et al, 2017(Han et al, , 2020Deng et al, 2018Deng et al, , 2019aDeng et al, , b, 2021Wang et al, 2020b;Sun et al, 2021;Shen et al, 2022). The Shunbei No.…”

“…With the oil and gas exploration and development of SSFZs in the Shunbei and adjacent areas, research on the structural characteristics and hydrocarbon significance of these SSFZs has attracted increasing attention (Qi, 2016(Qi, , 2021Jiao, 2017Jiao, , 2018Han et al, 2017Han et al, , 2020Deng et al, 2018Deng et al, , 2019aDeng et al, , b, 2021Cao et al, 2020;Wang et al, 2020a;Sun et al, 2021;Yun, 2021;Shen et al, 2022).…”