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In the tectonic framework of the seismically active Tian Shan, the Jiashi‐Keping region, located at the mountain's southwestern front, is characterized by frequent moderate (M 5.5–7.0) earthquakes, rather than by strong (M ≥ 7.5) earthquakes as observed in other Tian Shan regions. What structures are responsible for these moderate earthquakes and whether or not more destructive earthquakes can occur remain largely unexplored. Based on an integrated analysis of published geologic and geomorphic mapping data, Google Earth satellite images, published and our collected 2D petroleum seismic‐reflection profiles, as well as available seismologic data and InSAR observations, in this study, we investigate active structural geometries and their correlation with the 2020 Mw 6.0, the 2003 Mw 6.2, and other recorded major earthquakes. Our study indicates that active structures in the region can be grouped into the Kepintagh thrust imbricates, the Bachu‐Kepintagh transpressional fault system, and the Xiasuhong transtensional fault system. The recorded major earthquakes are correlated with the Kepintagh thrust imbricates and the Xiasuhong fault system, both of which are highly segmented along strike and have limited downdip extensions. Although the recorded seismicity is characterized by moderate earthquakes, larger earthquakes may be generated by (i) the Bachu transpressional fault system (Mw ≥ 7.3) and the Kepintagh lower ramp (Mw > 7.5). Our study highlights the control of fault geometry on the seismic rupture process and regional seismic activities and enhances our understanding of seismic hazards in the Tian Shan. Key points: Regional active faults include Kepintagh thrusting, Xiasuhong transtensional, and probably Bachu‐Kepintagh transpressional fault systemsRecorded moderate earthquakes are sourced by along‐strike discontinuous and downdip‐extension‐limited Kepintagh and Xiasuhong fault systemsLarger earthquakes (Mw≥7.3) cannot be excluded for the Bachu fault system and Kepintagh lower ramp in terms of their structural geometries [ABSTRACT FROM AUTHOR]

The Pamir is the northwestward continuation of the Tibet‐Himalaya orogen and translated ∼50–300 km northward toward the Tian Shan in Mesozoic‐Cenozoic times. Although this region has been studied extensively over the past few decades, our knowledge of the timing of mountain building in the Pamir is incomplete. In this study, we applied provenance analyses of Cretaceous‐Pliocene sediments from the Tierekesazi section in the Pamir‐Tian Shan corridor to reconstruct the Cenozoic evolution of the Pamir‐Tian Shan orogens. Provenance data from new detrital zircon U‐Pb ages and paleocurrent measurements indicate that the main source area of sediments in the studied section shifted from the Tian Shan to the Northern Pamir at ∼41–40 Ma. When combined with published provenance data, eastward decreasing sediment transport distances suggest that the Pamir was characterized by an asymmetric drainage system with larger drainage basins developed in the western Pamir than the eastern Pamir since the late Eocene. This resulted from either eastward decrease in precipitation rate caused by the uplift of the Pamir orocline or relatively low topography of the western Pamir. Furthermore, observed east and south directed paleocurrents and a dominance of Paleozoic detrital zircon U‐Pb ages in the upper Miocene‐Pliocene sediments suggest the SW Tian Shan was uplifted and became the primary provenance of the Tierekesazi section in the late Miocene. Simultaneously, the thrust belt of the Pamir propagated into its northern foreland and the present‐day east flowing drainage system in the eastern Pamir‐Tian Shan convergence zone was established in the late Miocene. Key Points: Asymmetric drainage patterns with larger rivers in the west and small rivers in the east have been established since the late EoceneThe Karakul‐Mazar terrane was uplifted and the primary source area of the Pamir‐Tian Shan corridor in the late Eocene‐middle MioceneThe present east flowing drainage systems we established in the late Miocene due to the crustal shortening in the Pamir‐Tian Shan corridor [ABSTRACT FROM AUTHOR]

Curvature of fold‐and‐thrust belts (FTBs) is a rather common feature in foreland basins. The problem of how curves in FTBs originate is essential for understanding the propagation of deformation and tectonic history of orogens. In this study, we carried out systematic paleomagnetic studies in the westernmost part of the Qiulitage FTB, southern Tian Shan foreland, where thrusting, strike‐slip fault, and tectonic boundary coexist. Our new results suggest that the study area has been subjected to ~20° clockwise rotations after ~5 Ma. Oroclinal test of the paleomagnetic data across the FTB suggests that oroclinal bending caused by the formation of the curved Qiulitage FTB is the dominate reason for these tectonic rotations. The Kalayuergun dextral strike‐slip transfer fault delimiting the western boundary of the Qiulitage FTB is a thin‐skinned structure accommodating the discrepancy in horizontal displacement on both sides of it. These results also suggest that the formation of the curved Qiulitage FTB should not be older than ~5 Ma, indicating that the southern Tian Shan foreland has experienced significant tectonic shortening since the latest Miocene to early Pliocene. Our new results, together with previous studies on deformation history, estimates of crustal shortening, GPS observations and earthquake records, suggest that the southern Tian Shan foreland has been subjected to significant deformation during the past ~5 million years, and the crustal shortening is still ongoing. Key Points: The western end of the Qiulitage FTB has been subjected to ~20° clockwise rotations, which occurred mostly after ~5 MaThe oroclinal bending caused by the formation of the arcuate Qiulitage FTB was the dominate reason for the clockwise rotationsSignificant deformation occurred during the past ~5 million years across the southern Tian Shan forelands, and it is still ongoing [ABSTRACT FROM AUTHOR]

• The study area is featured by three en echelon décollement folds. • The shortening rates of the three anticlines range from 0.35 mm/yr to 0.77 mm/yr. • Folds and strike-slip faults account for the crustal deformation in the study area. • Episodic deformation has been a response to the ongoing India-Asia convergence. Investigations of geometry and kinematics of foreland fold-and-thrust belts provide key information for understanding how convergence is accommodated in deformed forelands of orogenic belts. Here, we present the structural styles, deformation ages and shortening rates of three en echelon anticlines located at the west end of the Baicheng-Kuqa foreland fold-and-thrust belt. The results indicate that the three anticlines developed above the Eocene evaporites of the Kumugeliemu Group which constitute the décollement level in this typical thin-skinned tectonics. The initial growth of the East Awate and North Kalayuergun anticlines, as indicated by the syn-tectonic growth strata accumulations, occurred at ~5.3 Ma with shortening rates of ~0.70–0.77 mm/yr and ~0.40–0.43 mm/yr, respectively. Whereas, the initial folding time of the Middle Kalayuergun anticline is ~2.6–1.7 Ma, resulting in a shortening rate of ~0.35–0.65 mm/yr. The shortening rates are lower when compared with foreland deformation in the middle and eastern parts of the Baicheng-Kuqa fold-and-thrust belt. Such differences are mostly related to the strain partitioning caused by the NW-SE dextral strike-slip Kalayuergun fault as well as the influence of a dextral wrenching component in the west end of the Baicheng-Kuqa fold-and-thrust belt. Our study suggests that episodic tectonic deformation in the southern foreland of Tian Shan has been a response to the ongoing India-Asia convergence since the latest Miocene, and the spatial variability of crustal shortening rates has depended on regional tectonic differences. [ABSTRACT FROM AUTHOR]

The fold‐and‐thrust belts in the southern forelands of Tian Shan were tectonically deformed as a result of intracontinental deformation in response to the India‐Asia collision; therefore, they are essential for understanding tectonic evolution and basinward propagation of the Tian Shan Range. Although the reactivation of Tian Shan has long been studied, when and how this deformation was initiated and propagated are still controversial. In this study, we present new paleomagnetic results, anisotropy of magnetic susceptibility, tectonic rotations, and interpretations of subsurface seismic images on the Kalayuergun Structural Belt, western Baicheng Depression. Our new results suggest that the deformation of the Kalayuergun Structural Belt initiated at ~5.3 Ma and became young southeasterly, indicating that the deformation reached to the study area in the latest Miocene and propagated basinward progressively since then. The clockwise rotations, about half amounts of which must have been occurred at around ~5.3 Ma, can be linked to the activity of the Kalayuergun dextral strike‐slip fault on the western end of the anticline. Combined with previous results around Tian Shan, we suggest that the long range has been subjected to an episode of intensified tectonic deformation since the latest Miocene, which was caused by the accelerated northward motion of the Tarim Block and Pamir in response to the India‐Asia collision. Key Points: Neogene magnetostratigraphy and seismic images suggest that the deformation initiated at ~5.3 Ma and then propagated basinward progressivelyThe activity of the Kalayuergun dextral strike‐slip fault dominated the rotations of the late Miocene sedimentsThe intensified deformation since ~5.3 Ma along Tian Shan resulted from the accelerated northward motion of the Tarim Block and Pamir [ABSTRACT FROM AUTHOR]

The aeolian deposits in the coastal region of North China are important for reconstructing paleoclimate. In this paper, chronology, climatic proxies and chemical compositions of four loess sections were studied. Optically stimulated luminescence (OSL) dating results indicate that the coastal loess was accumulated during late Quaternary, with ages ranging from the penultimate glacial period to the latest Holocene. Both granulometric characteristics and geochemical properties indicate that the dust provenance of the coastal loess is partially different from that of the Chinese Loess Plateau, characterized by more proximal contributions. Except distal dust transported by northwesterly winter winds from the inland gobi and sand deserts, the coastal loess also contains proximal, local coarse particles, which were derived from the exposed shelf as well as neighboring hills. Multiple climatic proxies, including color, magnetic susceptibility and particle size parameters, correlate well with the marine SPECMAP δ18O record, indicating that climatic changes in the coastal region of North China during the late Quaternary was mainly controlled by variations of the East Asian monsoon, driven by changes in global ice volumes. • Luminescence dating of coastal loess in eastern North China. • Coastal loess contain both distal and proximal source materials. • Exposed shelf during glacial time serving as an important source for coastal loess. • Costal loess reflects orbital climatic fluctuations driven by East Asian monsoon. [ABSTRACT FROM AUTHOR]

• The intra-continental uplift initiated at 25–23 Ma in the northern Tian Shan mountain range. • The Borohoro range underwent another episode of uplift at 12–9 Ma. • The Middle-Late Miocene uplift occurred in the whole Tian Shan mountain range. Being one of the largest intra-continental orogens of the world, the Tian Shan orogenic belt was uplifted to its present elevation due to the far-field effect of the India-Asia convergence. In this study, we performed a systematic study on the Upper Oligocene-Quaternary sedimentary rocks from the southern Junggar basin, including conglomerate clast counting and detrital zircon U-Pb dating, to reconstruct the Late Cenozoic uplift history of the northern Tian Shan mountain range. The new detrital zircon U-Pb data provide new constrains on the Late Cenozoic intra-continental deformation of the Borohoro range. The Yili-Central Tian Shan and North Tian Shan were the major sources for the Junggar basin during the Latest Cretaceous-Paleogene period. At that time, the Borohoro range was characterized by low topography and wide drainage pattern. As the uplift of the North Tian Shan commenced at ~25–23 Ma, the high topography of the northern Borohoro range blocked the transport of sediments from the Yili-Central Tian Shan to the north. The North Tian Shan became the primary provenance area of the southern Junggar basin. According to sedimentary provenance analysis and geomorphologic survey, we infer that the Yili-Central Tian Shan started to uplift at 12–9 Ma. Combined with previously published data, our results suggest that the Middle Miocene uplift event most likely occurred in both the hinterland and foreland regions along the whole Tian Shan mountain range. [ABSTRACT FROM AUTHOR]

• The intra-continental deformation commenced at 26–23 Ma in Harke Mountain. • The exhumation of Harke Mountains intensified between 10 and 6 Ma. • The Late Miocene exhumation is probably a regional tectonic event of the Tian Shan. As the largest intra-continental mountain belt in Central Asia, the Tian Shan mountain range underwent a diachronous uplift history in different regions. The present crustal shortening rate of this mountain range is also characterized by an along-strike variation and decreases from west to east. The Harke Mountains, located in the middle part of the southern Tian Shan, accommodate a relatively lower crustal shortening rate but host the highest topography of this mountain range. This study aims to restore the Cenozoic mountain building history of the Harke Mountains. Detrital AFT and AHe analyses were conducted for Paleocene-Pliocene sediments and modern moraines in the Kuqa depression. An abrupt increase in the lag time of the detrital AFT young age components at 26–23 Ma indicates that the uplift of the southern Tian Shan initiated in the Late Oligocene-Early Miocene, which is consistent with the regional tectonic activation of the Tian Shan mountain range. In the Late Miocene, the basement of the Harke Mountains underwent rapid exhumation from ~10 to ~6 Ma. Comparing our result with previously published tectonic data, we infer that the intense exhumation in our study area corresponds to the intensified deformation of the whole Tian Shan mountain range in the Late Miocene, which was probably driven by the accelerated convergence between the Tarim and Tian Shan. [ABSTRACT FROM AUTHOR]

• Magnetic and color parameters reveal paleoclimatic changes since the late Miocene. • A basin-wide extreme aridification prevailed in the Tarim Basin since ~5.3 Ma. • The extreme aridification is mainly controlled by regional tectonics. The Tarim Basin, located in the rain shadow of High Asia, is an ideal basin for studying the long-term aridification history and the interplay between climate and regional tectonics. Here we report new environmental magnetic records from the foreland basin of southern Tian Shan. Our new magnetic records, together with the results of color parameters, suggest that the paleoenvironment in the study area changed abruptly since ~5.3 Ma. This result is consistent with other paleoclimatic records from different parts of the Tarim Basin, suggesting a basin-wide extreme aridification prevailed in the Tarim Basin since the beginning of the Pliocene. The long-term cooling trend of the climate in the Tarim Basin since the late Miocene was generally controlled by first-order global climate. However, the extreme aridification since ~5.3 Ma was dominantly controlled by decreased moisture transport caused by the final collision between Pamir and Tian Shan as a response to the northward displacement of the Pamir salient. [ABSTRACT FROM AUTHOR]