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The Denan Depression is a unique depression in the northeastern Qaidam basin, with a maximum Cenozoic sedimentary thickness of ~ 5 km. Detailed field work, interpretation of seismic profiles and analyzation of well data were conducted to define the Cenozoic tectonic evolution of the northeastern Qaidam basin. All geological evidences indicate that the Denan Depression is controlled by the northeast-directed Olongbulak Thrust at its southern boundary. The Denan Depression grew in concert with the development of the northeast-directed Olongbulak Thrust at least since it began to accept the Xiaganchaigou Formation, supporting the early Cenozoic growth of the northern Tibetan Plateau. Surface and subsurface data both point to enhanced tectonic activity since the Quaternary in the northeastern Qaidam basin, leading to a more individual Denan Depression relative to the main Qaidam basin. The northern boundary of the Denan Depression is a passive boundary, and no foreland developed at the northern slope of the Denan Depression.

International audience; Situated along the western termination of the Eastern Kunlun Mountains, the Qimen Tagh Range represents a key area to understand the Cenozoic basin-range interactions between the northeastern Tibetan Plateau and the Qaidam Basin. Within that region, several huge bow-like fault systems such as the Kunbei and Qimen Tagh fault systems accommodate the transpressive deformation but their kinematic evolution is still highly debated. Newly acquired seismic profiles and isopach maps of the Late Eocene sediments strongly suggest that the Kunbei fault system (consisting of the Kunbei, Arlar and Hongliuquan faults) in the southwestern Qadaim Basin was initially a left-lateral strike-slip fault system rather than a thrusting system. Growth strata indicate an Early Miocene onset age for this strike-slip deformation. However, earthquake focal mechanisms show that the present-day tectonic pattern of this fault system is dominated by NE-SW transpression. As for the Qimen Tagh fault system, numerous linear geomorphic features and fault scarps indicate that it was again a strike-slip fault system. Deformed sediments within the Adatan Valley prove that strike-slip motion prevailed during the Pleistocene, yet the present day deformation is marked by NE-SW transpression. Collectively, the Kunbei and Qimen Tagh fault systems were initially left-lateral strike-slip fault systems that formed during Early Miocene and Pleistocene respectively. Colligating with these southward younging left-lateral strike-slip faulting ages and the fact that these convex-northward structures converge to the center segment of active Kunlun fault in the east, we thus considered the Kunbei and Qimen Tagh fault systems as former western segments of the Kunlun fault once located further south in the present-day location of that fault. These faults gradually migrated northward since the Early Miocene while their kinematics changed from left-lateral strike-slip motion to NE-SW transpression.

Since the Cenozoic, the Tian Shan is rejuvenated by crustal shortening related to the ongoing India–Asia collision. However, the tectonic process prior to the Cenozoic remains ambiguous, especially in the Bogda area of the eastern Tian Shan. The continuous Late Paleozoic–Mesozoic sequences in the Bogda area record abundant information about the basin–mountain interaction. U–Pb (LA–ICP-MS) dating of detrital zircons from seven sandstone samples from Permian to Jurassic was used to investigate the changes of provenance and basin–mountain interaction in the Bogda area. During the Permian, proximal and synchronous pyroclastic materials were the major source. The Late Paleozoic magmatic belt in the North Tian Shan (NTS) had gradually become one of the main sources by the Late Permian, which implies the uplift and exhumation in the NTS area. This is interpreted in terms of near-source sedimentation in basin developing in a post-orogenic extension setting. The large range of U–Pb ages of detrital zircons observed in the Early–Middle Jurassic sediments encompasses most of the available sources implying a wide drainage pattern developing on a rather flat topography. Re-emergence of the Early Permian peak in the spectrum implies that the Bogda Mountains has existed as a gentle positive relief and began to provide materials to the submountain regions. The southern Junggar Basin extended towards to the south and evolved as a passively subsiding basin from the Middle Triassic to the Middle Jurassic. However, the synchronous pyroclastic (tuff) and the exhumed late Paleozoic detrital materials from the uplifted Bogda Mountains were the major component of the Upper Jurassic sediments. Associated to the conglomerate in the Kalaza Formation, the basin–range evolution entered a compression uplift stage. The basin pattern evolution of the Bogda area is consistent with that of the southern Junggar Basin.

This study uses apatite fission track (FT) analysis to constrain the exhumation history of bedrock samples collected from the Altai Mountains in northern Xinjiang, China. Samples were collected as transects across the main structures related to Palaeozoic crustal accretion events. FT results and modeling identify three stages in sample cooling history spanning the Mesozoic and Tertiary. Stage one records rapid cooling to the low temperature part of the fission track partial annealing zone circa 70 ± 10 °C. Stage two, records a period of relative stability with little if any cooling taking place between ∼75 and ∼25–20 Ma suggesting the Altai region had been reduced to an area of low relief. Support for this can be found in the adjacent Junngar Basin that received little if any sediment during this interval. Final stage cooling took place in the Miocene at an accelerated rate bringing the sampled rocks to the Earth's surface. This last stage, linked to the far field effects of the Himalayan collision, most likely generated the surface uplift and relief that define the present-day Altai Mountains.