Origin and growth mechanisms of strike-slip faults in the central Tarim cratonic basin, NW China

Composite Strike-Slip Deformation Belts and Their Control on Oil and Gas Reservoirs: A Case Study of the Northern Part of the Shunbei 5 Strike-Slip Deformation Belt in Tarim Basin, Northwestern China

“…These structures were delimited by layer beddings, and referring to Figure 10A, they were deduced to be formed at the end of the Middle Ordovician. This time is identical to the age of the first periodic calcite vein in fractures (Wu et al, 2020;Wang et al, 2021). Except for the transpressional structures in Figures 7C,E, the structures in the T 7 0 reflector were mostly transtensional zones, appearing as en echelon patterns on the plan view (Figure 5B) and normal faults in vertical profiles (Figures 7, 8).…”

“…The formation of the SB5 strike-slip fault is related to plate tectonics around the Tarim Plate (basin). The activity at the end of the Middle Ordovician was caused by the near N-S compression, which is related to the closing of the Proto-Tethys Ocean (Wu et al, 2020), during which the SB5 strikeslip fault was a simple shear belt. The activity at the end of the late Ordovician is related to the southward subduction of the Northern Kunlun Ocean, the northwestward subduction of the Altyn Ocean and the southward subduction of the Northeast Tianshan-Junggar Ocean (Wu G. H. et al, 2016;Wu et al, 2020), during which the SB5 strike-slip fault was a transtensional zone.…”

“…The activity at the end of the Middle Ordovician was caused by the near N-S compression, which is related to the closing of the Proto-Tethys Ocean (Wu et al, 2020), during which the SB5 strikeslip fault was a simple shear belt. The activity at the end of the late Ordovician is related to the southward subduction of the Northern Kunlun Ocean, the northwestward subduction of the Altyn Ocean and the southward subduction of the Northeast Tianshan-Junggar Ocean (Wu G. H. et al, 2016;Wu et al, 2020), during which the SB5 strike-slip fault was a transtensional zone. From the Silurian to Middle Devonian, the east Kunlun-Qaidam Plate and middle Kunlun terrain attached to the Tarim Plate, causing the closing of the Altyn Ocean and the Northern Kunlun Ocean, respectively.…”

“…The active time of SB5 is difficult to determine and its formation mechanism is not clear. U-Pb isotopic dating of calcite in fractures in Ordovician Carbonate rocks indicated that the formation of SB5 began at the end of the Middle Ordovician (Wu et al, 2020). However, according to seismic data, the formation time of strike-slip faults in the Tabei and Tazhong uplifts was in the late Ordovician and the strike-slip faults in the Tazhong uplift formed earlier than those in the Tabei uplift (Wu et al, 2012;Zhen et al, 2015;Han et al, 2017;Deng et al, 2018;Wu et al, 2018;Huang, 2019).…”

Characteristics of strike-slip fault-related reservoirs and the significance for hydrocarbon accumulation in the central Tarim Basin: Insights from the modern karst model

“…Under this background, strike-slip faults are widely developed inside the Tarim craton, which in the eastern part are primarily in the Tazhong Uplift and its north, the Shuntuoguole Uplift, and the Tabei Uplift (Figure 1C). Primarily in the NNE-trending near-parallel faults in the Tazhong Uplift and its northern slope and the NNE-NNW trending X-shaped faults in Tuoputai-Halahatang area of the Tabei Uplift, the strike-slip fault system is mainly developed in the middle and lower Ordovician carbonate rocks formed by the tectonic movement in the middle Caledonian (He et al, 2006;Jia et al, 2007) and experienced multiple activities in the later period (Deng, et al, 2021b;Wu, et al, 2021). Superimposed by multistages of fluid reformation, large-scale reservoirs were formed in the Ordovician carbonate rocks in the northern slope of the Tazhong Uplift, the Shuntuoguole Low Uplift, and the Tabei Uplift of the Tarim Basin (Lu et al, 2017;Ding, et al, 2020;Qi, 2020), which played an important role in hydrocarbon accumulation.…”