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Arguments for recognizing autogenic vs. allogenic signals in the stratigraphic record are still far from settled, as is the decoding of unsteady allogenic responses to climate vs. tectonic forcing. We offer the case of late Mesozoic Xuanhua basin in the western Yanshan fold‐and‐thrust belt of North China to make these points. The study area is an intramontane basin that has allowed detailed structural, sedimentological, and provenance analyses in a kilometre‐thick succession (the Tuchengzi Formation) of alluvial fan, fluvial, lake‐delta and lacustrine deposits. Extensive geological mapping provided confidence of near‐basinwide later correlation of strata, revealing two large‐scale upward‐coarsening (CU) successions each 80–240 m thick, with prominent vertical changes from lacustrine through deltaic and fluvial to alluvial fan deposits. Two intervals of thrust‐related growth strata identified in the Tuchengzi Fm suggest that the CU successions were the signals of tectonic uplift and accommodation change related to Likouquan and the Mapu thrusting. In the lower CU succession, there is a stacking (30+) of small‐scale (3–16 m thick) upward‐fining cyclothems that are argued to have been generated by alternating wet‐dry climate cycles. The wet half‐cycle is argued to have initiated with high sediment and water discharge of flood‐generated mass flows into the lake and ended with accumulation of lacustrine mudstones as lake level rose. The lake deposits include the maximum flooding during the wet half‐cycle. The dry half‐cycle was characterized by continued lacustrine deposits, but increased evidence of subaerial exposure (rooting, paleosols, and mudcracks) argued to result from falling of the lake level under dry conditions. [ABSTRACT FROM AUTHOR]

A well‐constrained plate deformation model may lead to an improved understanding of sedimentary basin formation and the connection between subduction history and over‐riding plate deformation. Building quantitative models of basin kinematics and deformation remains challenging often due to the lack of comprehensive constraints. The Bohai Bay Basin (BBB) is an important manifestation of the destruction of the North China Craton, and records the plate kinematic history of East Asia during the Cenozoic. Although a number of interpretations of the formation of the BBB have been proposed, few quantitative basin reconstruction models have been built to test and refine previous ideas. Here, we developed a quantitative deformation reconstruction of the BBB constrained with balanced cross‐sections and structural, stratigraphic and depositional age data. Our reconstruction suggests that the basin formation process was composed of three main stages: Paleocene‐early Eocene (65–42 Ma) extension initiation, middle Eocene‐early Oligocene (42–32.8 Ma) extension climax and post‐Oligocene (32.8–0 Ma) post‐extensional subsidence. The deformation of the BBB is spatially heterogeneous, and its velocity directions rotated clockwise during the basin formation process. The reconstruction supports the interpretation that the BBB formed via strike‐slip faulting and orthogonal extension and that the basin is classified as a composite extensional‐transtensional basin. We argue that the clockwise rotation of the basin velocity field was driven by the counter‐clockwise rotation in the direction of Pacific Plate subduction. The kinematics of the BBB imply that the Pacific Plate may have been sufficiently coupled to the over‐riding East Asian Plate during the critical period of Pacific Plate reorganization. The new reconstruction provides a quantitative basis for studies of deformation processes not only in the vicinity of the BBB, but also more broadly throughout East Asia. [ABSTRACT FROM AUTHOR]

The Xunhua, Guide and Tongren intermontane basin system in the NE Tibetan Plateau, situated near the Xining basin to the N and the Linxia basin to the E, is bounded by thrust fault-controlled ranges. These include to the N, the Riyue Shan, Laji Shan and Jishi Shan ranges, and to the S the northern West Qinling Shan ( NWQ). An integrated study of the structural geology, sedimentology and provenance of the Cenozoic Xunhua and Guide basins provides a detailed record of the growth of the NE Tibetan Plateau since the early Eocene. The Xining Group ( ca. 52-21 Ma) is interpreted as consisting of unified foreland basin deposits which were controlled by the bounding thrust belt of the NWQ. The Xunhua, Guide and Xining subbasins were interconnected prior to later uplift and damming by the Laji Shan and Jishi Shan ranges. Their sediment source, the NWQ, is constrained by strong unidirectional paleocurrent trends towards the N, a northward fining lithology, distinct and recognizable clast types and detrital zircon ages. Collectively, formation of this mountain-basin system indicates that the Tibetan Plateau expanded into the NWQ at a time roughly coinciding with Eocene to earliest Miocene continental collision between India and Eurasia. The Guide Group ( ca. 21-1.8 Ma) is inferred to have been deposited in the separate Xunhua, Guide and Tongren broken foreland basins. Each basin was filled by locally sourced alluvial fans, braided streams and deltaic-lacustrine systems. Structural, paleogeographic, paleocurrent and provenance data indicate that thrust faulting in the NWQ stepped northward to the Laji Shan from ca. 21 to 16 Ma. This northward shift was accompanied by E-W shortening related to nearly N-S-striking thrust faulting in Jishi Shan after 11-13 Ma. A lower Pleistocene conglomerate (1.8-1.7 Ma) was deposited by a through-flowing river system in the overfilled and connected Guide and Xunhua basins following the termination of thrust activity. All of the basin-mountain zones developed along the Tibetan Plateau's NE margin since Indian- Tibetan continental collision may have been driven by collision-induced basal drag of old slab remnants in the manner of N-dipping and flat-slab subduction, and their subsequent sinking into the deep mantle. [ABSTRACT FROM AUTHOR]