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Objective The Beishan Range occupies a key position in Central Asia. This study aims to deepen the understanding of the timing, intracontinental deformation processes, and their dynamic mechanisms in the Late Mesozoic on the southern margin of the Central Asian Orogenic Belt (CAOB). Methods We conducted detailed analyses of the Early Cretaceous extensional and earlier compressional structures in the southeastern Beishan Range through field geological observations, interpretation of 2D reflection seismic profiles, and apatite fission track thermochronology. Conclusion Field observations show that Lower–Middle Jurassic strata have been strongly deformed by numerous thrusts and folds. 2D seismic reflection profiles reveal two NE- to NEE-striking normal faults. The Suosuojing fault is a SE-dipping low-angle listric normal fault, while the Wudaoming fault is a NW-dipping high-angle normal fault. These normal faults cut through the early-formed fold-thrust system, indicating a transition from contraction to extension. The Suosuojing and Wudaoming faults, respectively, define the northwestern and southeastern boundaries of the Early Cretaceous Zongkouzi basin. The Zongkouzi basin exhibits a graben geometry, with Lower Cretaceous strata displaying typical growth-strata relationships, suggesting that the normal faults were active during the late Early Cretaceous. Thermal history modeling results from apatite fission track data indicate that the footwall of the Suosuojing fault experienced rapid cooling between 132 and 110 Ma. This rapid cooling phase was closely related to the footwall exhumation during the normal slip of the Suosuojing fault. We argue that the Late Mesozoic intracontinental contraction–extension transition in the southeastern Beishan Range likely occurred between ~133 Ma and ~129 Ma in the late Early Cretaceous. The collapse of the thickened crust and coupled mantle upwelling triggered the Early Cretaceous extensional deformation in the southern CAOB.

The Tianshan range, a Paleozoic orogenic belt in Central Asia, has undergone multiple phases of tectonic activities characterized by the N–S compression after the early Mesozoic, including the far‐field effects of the Cenozoic Indian–Asian collision. However, there are limited reports on the tectonic deformation and initiation of Triassic intracontinental deformation in the Tianshan range. Understanding this structural context is crucial for interpreting the early intracontinental deformation history of the Eurasian continent during the early Mesozoic. Growth strata and syn‐tectonic sediments provide a rich source of information on tectonic activities and have been extensively used in the studies of orogenic belts. Based on detail fieldwork conducted in this study, the middle–late Triassic Kelamayi Formation of the northern Kuqa Depression in the southern Tianshan fold‐thrust belt has been identified as the typical syn‐tectonic growth strata. The youngest detrital zircon component in two lithic sandstone samples from the bottom and top of the Kelamayi growth strata yielded U‐Pb ages of 223.4 ± 3.1 and 215.5 ± 2.9 Ma, respectively, indicating that the maximum depositional age of the bottom and top of the Kelamayi growth strata is 226–220 and 218–212 Ma. The geochronological distribution of detrital samples from the Early–Middle Triassic and Late Triassic revealed abrupt changes, suggesting a new source supply resulting from tectonic activation in the Tianshan range. The coupling relationship between the syn‐tectonic sedimentation of the Kelamayi Formation and the South Tianshan fold‐thrust system provides robust evidence that the Triassic intracontinental deformation of the South Tianshan range began at approximately 226–220 Ma (during the Late Triassic) and ended at approximately 218–212 Ma. These findings provide crucial constraints for understanding the intraplate deformation in the Tianshan range during the Triassic. [ABSTRACT FROM AUTHOR]

[Objective] The Beishan Range occupies a key position in Central Asia. This study aims to deepen the understanding of the timing, intracontinental deformation processes, and their dynamic mechanisms in the Late Mesozoic on the southern margin of the Central Asian Orogenic Belt (CAOB). [Methods] We conducted detailed analyses of the Early Cretaceous extensional and earlier compressional structures in the southeastern Beishan Range through field geological observations, interpretation of 2D reflection seismic profiles, and apatite fission track thermochronology. [Conclusion] Field observations show that Lower-Middle Jurassic strata have been strongly deformed by numerous thrusts and folds. 2D seismic reflection profiles reveal two NE- to NEE-striking normal faults. The Suosuojing fault is a SE-dipping low-angle listric normal fault, while the Wudaoming fault is a NW-dipping high-angle normal fault. These normal faults cut through the early-formed fold-thrust system, indicating a transition from contraction to extension. The Suosuojing and Wudaoming faults, respectively, define the northwestern and southeastern boundaries of the Early Cretaceous Zongkouzi basin. The Zongkouzi basin exhibits a graben geometry, with Lower Cretaceous strata displaying typical growth-strata relationships, suggesting that the normal faults were active during the late Early Cretaceous. Thermal history modeling results from apatite fission track data indicate that the footwall of the Suosuojing fault experienced rapid cooling between 132 and 110 Ma. This rapid cooling phase was closely related to the footwall exhumation during the normal slip of the Suosuojing fault. We argue that the Late Mesozoic intracontinental contraction-extension transition in the southeastern Beishan Range likely occurred between ~133 Ma and ~129 Ma in the late Early Cretaceous. The collapse of the thickened crust and coupled mantle upwelling triggered the Early Cretaceous extensional deformation in the southern CAOB. [ABSTRACT FROM AUTHOR]

The Hadamengou gold deposit in Baotou City, Inner Mongolia is an important large gold deposit in the Wulashan - Daqingshan metallogenic belt, with great prospecting potential. To give full play to remote sensing technology in geological prospecting, this study extracted the mineralization alteration information of the Hadamengou gold deposit from remote sensing data of different satellites. Based on the spectral characteristics of alteration minerals in the mining area, this study proposed a comprehensive processing method that extracted iron staining information from the Landsat8 OLI and WorldView - 3 data, hydroxyl information from the ASTER and WorldView -3 data, and carbonation information from the ASTER data through principal component analysis. As a result, two alteration zones were delineated based on the distribution patterns of alteration anomalies and the geological map analysis of the mining area. By combining the study results of the ore - controlling structures, it is believed that the metallogenic hydrothermal proceeses of the Hadamengou gold deposit were closely related to structures. This study can provide a reference for the prospecting for the same type of gold deposits in the Wulashan - Daqingshan metaHogenic belt and can guide the peripheral prospecting of the Hadamengou gold deposit. [ABSTRACT FROM AUTHOR]