Cenozoic Uplift Research Articles

Pulsed uplift of the South Tianshan since the Late Miocene indicated by the linear inversion on river longitudinal profiles

The early Cenozoic collision and subsequent continuous convergence between the Indian and Eurasian plates reactivated the Tianshan orogen in the Central Asia and caused multistage uplift of the mountain range. The modern Tianshan, with high mountain peaks of >7000 m, forms very prominent topography that profoundly affects the regional tectonics and climate. However, the late Cenozoic uplift process and topography growth of the South Tianshan remain controversial. River longitudinal profile inversion provides a distinctive way to reveal rock uplift history since the late Cenozoic. In this study, we presented linear inversion on river longitudinal profiles of four drainage basins originating from high mountains in the South Tianshan. The inversion results from two basins in the northern flank show fast and continuous increases in the uplift rates from about 0.1–0.2 mm/a to 0.6–1.0 mm/a since 4 Ma. While in the southern flank, the uplift rates of the two basins increased gradually from about 0.1 mm/a to 0.2 mm/a before 10 Ma and from 0.2 mm/a to 0.4 mm/a around 10 Ma and 6 Ma, respectively. Our results combined with recently published chronological data in this region indicate that the South Tianshan experienced a pulsed tectonic uplift process since the Late Miocene. Moreover, the pulsed tectonic uplift should lead to an elevated South Tianshan during 6–4 Ma, coinciding well with the ∼5.3 Ma extreme aridification in the Tarim Basin, thus supporting that the rain shadow effect caused by high topography of South Tianshan is a critical reason for aridification.

Cenozoic faulting leading to petroleum escape in SW Ordos Basin, China: Evidence from fault-related calcite in situ U-Pb dating, rare earth elements and fluid inclusions

Understanding the link between fault activity and movement to petroleum escape is crucial for assessing the petroleum exploration potential in sedimentary basins. As a significant petroliferous basin in China, the Ordos Basin hosts the world-class uncompartmentalized Jingbian natural gas field within the Ordovician marine carbonate reservoirs. However, the role of the unique exhumation history and the Cenozoic faulting in the formation of such large-scale oil-gas fields remain unclear. Our study combines fault-related calcite U-Pb dating with fluid inclusions analysis offers a unique opportunity to trace petroleum leakage along the the carbonate strata brittle fault zones in the SW Ordos Basin. Calcite samples collected from the carbonate fault zone and across the Ordovician carbonate strata in the SW Ordos Basin reveal clear positive Eu anomaly, slight positive Y anomaly, the lack of positive La and Gd anomalies, and the absence of a negative Ce anomaly. The Y/Ho ratios range from 29 to 36, with an average value of 32, indicating calcite formation in a hydrothermal environment during fault activation. U-Pb dating of these fault-related calcites yields ages of 32.8 ± 3.3 Ma and 23.7 ± 7.4 Ma. Raman spectroscopy of fluid inclusions reveals the presence of CH4 gas, coeval with the fault-related calcite. The homogenization temperatures (Th) of aqueous inclusions coeval with CH4 inclusion from two calcite veins range from 140.0 to 172.4 °C (average Th = 157.8 °C, n = 16) and 127.7–154.3 °C (average Th = 142.2 °C, n = 18). Low temperature thermochronology suggest rapid uplift since 40 Ma, potentially linked to fault activity. The Cenozoic erosion rate was 0.06 mm/y during the ∼9 Myr period from 32.8 to 23.7 Ma in the SW Ordos Basin, suggesting that Cenozoic faulting may have created permeable pathways for petroleum escape. This study provides a temporal link between Cenozoic uplift, faulting, and petroleum loss in SW Ordos Basin.

Landform evolution of the Qilian Shan since 120 Ma revealed by apatite fission track data

The Cenozoic uplift of the Qilian Shan mountain range is intimately connected with the collision of the Indian and Eurasian plates, although the mechanism of deformation is still unclear due to the large distance between the Qilian Shan and the plate collision boundary. The first requirement if we are to determine this mechanism is to obtain the uplift process of the Qilian Shan range, which remains a matter of debate. We compiled apatite fission track data from previous studies of the Qilian Shan range to investigate the spatial and temporal disparities or similarities of the exhumation process. Most of the age-evolution profiles and thermo-modelling results show a low exhumation rate from 80 to 20 Ma, corresponding to shorter apatite fission track lengths, indicating a lower rate of erosion and lower relief across the whole Qilian Shan region. The results also reveal two stages of rapid exhumation: during the Cretaceous (120–80 Ma) and since the Miocene (20–0 Ma). The exhumation history of the Qilian Shan range shows no significant spatial difference and outward growth was limited at the southern and northern edges after 5 Ma. This temporal and spatial pattern for the exhumation of the Qilian Shan range suggests that there was probably no obvious uplift at the time of the initial collision of the Indian–Tibetan plates and support the proposal that the whole Qilian range has uplifted synchronously since 20 Ma.

Eurasia Basin Composite Tectono-Sedimentary Element

The Eurasia Basin formed by continental break-up and separation of the Lomonosov Ridge from the northern Barents–Kara Shelf at about 56–54 Ma. It was a restricted oceanic basin from its formation up until the Miocene, when extensive water circulation between the North Atlantic and Arctic oceans commenced through the Fram Strait gateway. The opening of the oceanic gateway had a large impact on palaeoceanography and palaeoclimate, which evolved from an Eocene greenhouse to a Neogene icehouse associated with northern hemisphere glaciations. The Eocene–present sedimentary fill of the Eurasia Basin was mainly sourced from surrounding shelf areas in the Barents, Kara and Laptev seas, which experienced widespread Cenozoic uplift and erosion during several phases. The stratigraphy of the Eurasia Basin is poorly constrained due to a lack of boreholes penetrating the basin fill. We therefore have to rely on seismic stratigraphy and tentative ages assigned to sequences and their boundaries terminating on top of oceanic basement of known age. This contribution covers two tectono-sedimentary elements (TSEs): the Eurasia Basin Oceanic TSE and the Eurasia Basin Prograded Margin TSE, which are closely connected and difficult to draw a distinct boundary between.

Late Cretaceous cooling and pulsed cenozoic uplift in the Fenghuang Shan: Insights into the tectonic evolution of the Qinling Orogen, central China

Reactivation of the Qinling Orogen since the Late Jurassic has been controlled by the combined effects of the convergence between the South and North China blocks, the subduction of the Pacific Plate, and the northeastward expansion of the Tibetan Plateau. In this study, we present new apatite (U–Th)/He ages from a vertical transect in the Fenghuang Shan located in the North Daba Mountains, where rapid cooling at ∼95-90 Ma is identified. Inverse thermal history modeling results reveal another pulse of accelerated exhumation at ∼50 Ma. In addition, we analyzed longitudinal profiles of rivers draining the northern flank of the Fenghuang Shan and identified knickpoints that break channels into gentle upstream and steep downstream segments. We deduce that these knickpoints were initiated by an increase in the mountain-bounding fault throw, based on nearly constant chi values (an integral to the upstream drainage area distribution) and a reliance of knickpoints’ retreat distances on catchment areas. Assuming a linear slope exponent and erodibility of 10−6 m0.1/a, we estimated knickpoint ages to be ∼5.7 ± 1.7 Ma. We interpret the Late Cretaceous cooling as a result of lithospheric extensional collapse following the Late Jurassic intra-continental compression between the North and South China blocks. The early Cenozoic exhumation might relate to the active normal faulting, as a far-field response to the west Pacific back-arc extension. The expansion of the NE Tibetan Plateau may have triggered the late Miocene uplift of the mountain range. The multiple episodes of tectonic events in the Fenghuang Shan might correspond to various geodynamic regimes on the tectonic evolution in the Qinling Orogen.

Northward expansion of the West Kunlun orogenic belt during the Cenozoic and its implications for the evolution of the northwest Tibetan Plateau: Constraints from sediment dispersal patterns in the Buya Basin, China

The West Kunlun orogenic belt, which defines the northwestern margin of the Tibetan Plateau, holds important information on plateau growth. Despite its significance, views about its uplift history continues to be under debate, with two competing hypotheses involving episodic uplift or northward expansion, related to a fixed or movable plateau boundary, respectively. The Buya Basin, a small basin located between the North and South Kunlun terranes, is key to understanding the Cenozoic uplift history of the West Kunlun orogenic belt. In this study, we conducted sedimentary and detrital zircon UPb geochronological analyses on the Cenozoic sediments of the Buya Basin. According to the findings of the sedimentary investigation, the Cenozoic strata of the basin generally show gradual changes from low- to high-energy deposition interrupted by a reverse trend in the Anjuan Formation. Moreover, the detrital zircon UPb geochronological results indicate that the Buya Basin received sediments initially from the Songpan–Ganzi and South Kunlun terranes during the deposition of the Keziluoyi to Pakabulake formations and then from the South and North Kunlun terranes during the deposition of the Artux Formation. This change in sediment dispersal patterns demonstrates that the uplift of the West Kunlun orogenic belt has expanded northwards to the North Kunlun terrane, which suggests that the northwestern boundary of the Tibetan Plateau has been a northward-moving feature in the context of India–Eurasia convergence. Along with previous studies, we suggest that the northward expansion of the northwest Tibetan Plateau is accommodated by decoupling deformation along the southern Tarim Basin, with northward thrusting of the foreland fold-and-thrust belts in the upper crust and southward underthrusting in the lower plate.

Late Cenozoic uplift of the Liupan Mountains: Evidence from the Neogene loess deposits

Late Cenozoic uplift of the Liupan Mountains: Evidence from the Neogene loess deposits

Neogene and Pleistocene geodynamics: the paleoseismic evolution of Armorica (Western France)

The evolution of the passive Armorican margin (Western France) during the Neogene and Quaternary was analyzed using field data. The morphology of the margin attests to a late Hercynian shaping, further deformation during the Mesozoic mid-Atlantic opening, during the Alpine Orogeny, and ultimately, a Late Cenozoic uplift, mostly related to an onshore isostatic accommodation in response to erosion and limited tectonic activity. A very limited strike–slip dynamic, with very low seismicity, accommodated the Neogene–Pleistocene N170 strains around the rigid Armorican terrane. The South Armorican domain and English Channel floor include shear zones that adjusted the Alpine convergence, facilitating its transpressive slip to the west. The Permo-Triassic N150 faults were reactivated during the inversion phases that began after the Bartonian under the distal control of the Alpine convergence and the decrease in the Atlantic spreading rate after 34 Ma. The Armorican marine platforms were stable after the late Eocene and slightly subsident, experiencing pulsed episodes of transient lithospheric doming during the Neogene and Quaternary. Co-seismic activity onshore without surface rupture was recorded around ∼5.3 Ma, ∼3.7 Ma, ∼2.4–1.2 Ma, and ∼400–250 ka, in tandem with an inland exhumation driven by isostatic adjustment due to an intensification of periglacial erosion at the onset of the early interstadials or by agriculture. Low-magnitude and ubiquitous shallow seismic activities seem to be related today to an isostatic uplifted old brittle–ductile transition due to the accumulation of shearing strain.

The well log and seismic expression of faults in the Wisting field, Barents Sea

Seismic facies in large fault zones (dam to km throw) can rarely be constrained with well log data. High-resolution seismic data (ca. 3.1 × 3.1 m bins) from the highly faulted Wisting field in the Barents Sea, is compared with log data along a horizontal and a vertical well. The target of both wells is the Lower Jurassic, oil-bearing Stø Fm., which due to Cenozoic uplift and erosion is just ca. 250 m below sea floor. From SW to NE, the horizontal well crosses a horst structure before landing in the Stø Fm. The inner zones of the two normal faults bounding the horst show low acoustic impedance (Aimp) and high porosity. The horst is characterized by a chaotic seismic pattern, partly caused by several faults made visible by seismic attributes. The well logs show large variance within the horst which may be caused by small faults and fractures that were observed during drilling in addition to mud losses. Along the horizontal well path NE of the horst, the Stø Fm. is characterized by strongly varying porosity and Aimp logs, and the seismic horizons around the borehole are offset by several small faults. Farther NE from the horst in the last well interval, the Stø Fm. shows a clean sand with high porosity and a continuous seismic reflector along the well path. The vertical well is between two SW dipping normal faults, and it shows oil only. A gas cloud identified by a flat spot is observed SW of the well, on the footwall of the SW-most fault. The gas cloud has ca. 20% lower Aimp than the oil zone. The two faults exhibit inner fault zones which start at about the Stø Fm. in the hanging wall and are characterized by low Aimp values. The fault blocks do not show these low Aimp values, which means that gas rather than shale smears could be responsible for the low Aimp along the faults. The low Aimp fault zones can be followed up to the upper regional unconformity (URU). The Quaternary above the URU shows a weak fault pattern, which could explain how the gas from the reservoir is conducted through the faults up to the seabed. This emphasizes the importance of faults as fluid conduits in the area.

No significant provenance changes in the Hoh Xil Basin, central-northern Tibetan Plateau, from the Late Cretaceous to the Early Miocene

The construction and uplift of the Tibetan Plateau has played a critical role in Cenozoic global climatic cooling due to extensive chemical weathering and establishment of the Asian monsoons. However, the models, mechanisms, and timing of Tibet's uplift remain rigorously debated. Important outstanding questions include what were surface elevations of the Tibetan Plateau prior to the Paleogene India-Asia collision and what mechanisms were responsible for the Cenozoic uplift of the central Tibetan Plateau. In this study, we integrated new detrital zircon data from the Tuotuohe Basin, a sub-basin of the Hoh Xil Basin in the central Tibetan Plateau, with paleocurrent directions, petrological textures, sedimentary facies, and eastern and western Hoh Xil Basin isotopes to investigate the source-to-sink relationship between the Tanggula Range and the Hoh Xil Basin. Any notable provenance shifts would have implications for the topographic evolution of the central and northern Tibet and proposed plateau uplift mechanisms. Our detrital zircon data from the Tuotuohe sub-basin revealed no provenance changes between ca. 37 and ca. 20 Ma. Detrital zircon data from the Tuotuohe section and the eastern and western Hoh Xil Basins, paleocurrent directions, petrologic analysis, strata characteristics, and isotopic evidence suggest that there was a single expansive Hoh Xil Basin from the Late Cretaceous to the Early Miocene. Furthermore, the Tanggula Range has been the primary source region for the Hoh Xil Basin since the Late Cretaceous. However, the Fenghuo Range may have provided a significant secondary source of detritus starting in the Late Oligocene-Early Miocene. Our results imply that there was established topographic relief in central-northern Tibet between mountainous highlands in the south and the Hoh Xil Basin in the north since the Late Cretaceous. The Tanggula Range-Hoh Xil Basin experienced surface deformation and uplift from the Late Cretaceous to ca. 40 Ma, induced by the Lhasa-Qiangtang and India-Asia collisions, after which the deformation intensity ceased by ca. 27–24 Ma. Therefore, the additional ∼1.5 km surface uplift of the Hoh Xil Basin since the Middle Miocene cannot be the result of crustal shortening. Instead, surface uplift may have been caused by the convective removal of the mantle lithosphere or magmatic inflation, which explains the sub-horizontal attitudes of the Middle Miocene Wudaoliang Formation in the region.

Review of sedimentary basin evolution in Cambodia based on tectonic setting and logical information

The paper aims to synthesize the evolution of sedimentary basins in Cambodia based on a comprehensive information on tectonic setting and existing database of their formation and sedimentation. The study includes a review on tectonic setting of Indochina, the formation of sedimentary basins around Cambodia, and the accessible data on sedimentary basins in Cambodia. Indochina, as well as Cambodia, had been influenced by the collision of three different plates or terranes such as the South China, Sibumasu-Sukhothai, and Paleo-Pacific that are associated with the evolution of Paleozoic-Mesozoic Basins namely Khorat and Kampong Som Basins. These two oldest basins, are interpreted as a Paleozoic – Mesozoic foreland basin that initially formed due to rifting during the Late Carboniferous to Late Permian, and later basin inversion and erosion took place due to the Mesozoic to earliest Cenozoic uplift. Then, Cambodia was affected by Tertiary strike-slip fault movements that also influenced the formation of Tonle Sap, Svayrieng and Khmer Tertiary rift basins. Tonle Sap and Svayrieng Basins are interpreted to be formed by extension during the Middle Eocene – Early Oligocene and inversion, uplift and denudation during the Miocene. The Khmer Basin was formed by rifting during the Eocene to the Late Oligocene, followed by rapid thermal subsidence from the Early to Middle Miocene. Finally, Khmer basin was affected by the Middle – Late Miocene to Pleistocene inversion.

Tectonics of the Continental Barents Sea Shelf (Russia): Formation Stages of Basement and Sedimentary Cover

Based on the results of field complex geophysical studies in the northwestern part of the Russian sector of the Barents Sea shelf, as well as on the processing and comprehensive interpretation of new and retrospective geophysical materials in the volume of 25 500 linear kilometers and deep well drilling data in the section of the Barents Sea sedimentary cover identified regional tectonostratigraphic units: (i) Paleozoic complex (between reflecting horizons VI(PR? ) and I2(P‒T)); (ii) the Triassic complex (between reflecting horizons I2(P‒T) and B(T‒J)); (iii) the Jurassic complex (between reflecting horizons B(T‒J) and V′(J3‒K1)); (iv) the Cretaceous‒Cenozoic complex (between reflecting V′(J3‒K1) and the Barents sea floor). According to the structural analysis’ results, three structural floors are established: the lower structural floor, which includes Riphean terrigenous-affusive sediments and Lower Paleozoic‒Lower Permian terrigenous-carbonate sediments; the middle structural floor is formed mainly by carbonate sediments of Upper Devonian‒Lower Permian; the upper structural floor combines terrigenous sediments of Lower and Upper Permian, Mesozoic and Cenozoic sediments. The authors present a new tectonic model of the Barents Sea region, including elements of all structural floors with subfloors. In accordance with the tectonic zoning, paleostructural and paleotectonic analyses, the article outlines the main stages of the Barents Sea shelf development: stage of the Late Proterozoic compression and Early-Middle Paleozoic continental rifting (I), Late Paleozoic stabilization stage (II), Early Mesozoic tectogenesis stage (III), Middle Mesozoic thermal subsidence stage (IV), Late Jurassic stabilization stage (V), Cretaceous sagging stage (VI) and the final stage as a Cenozoic uplift over a large part of the Barents Sea shelf (VII). In the northwestern part of the Russian sector of the Barents Sea shelf, synchronous dipping of the sedimentary cover basement took place, associated with spreading and formation of the Arctic Ocean.

Khangai Intramantle Plume (Mongolia): 3D Model, Impact on Cenozoic Tectonics and Comparative Analysis

The Khangai plume is located beneath Central and Eastern Mongolia and corresponds to the mantle volume with significantly reduced longitudinal wave (P) velocities. The plume was identified as a result of the analysis of the MITP08 volumetric model of variations in P wave velocities, expressed as deviations of these velocities from the mean values for the corresponding depths in percent. Above the plume, the lithospheric mantle is thinned to ~50 km. Particularly low velocities (up to –6%) were found in the sublithospheric mantle down to a depth of 400 km. The main body of the plume is located under the Khangai Highland and spreads north to the edge of the Siberian Platform. The Khentei branch of the plume is identified southeast of the Khentei Highlands. It is connected to the main body of the plume at depths of 800–1000 km. Branches of the plume and its Khentei branch spread to Transbaikalia. The size of the plume decreases with depth, and its deepest part (1250–1300 km) is located under the southern part of the Khangai Highland. On the Earth’s surface, the main body of the Khangai plume corresponds to a Cenozoic uplift up to 3500–4000 m high in the south of the Khangai Highland. From the southeast, the territory of the Khangai plume and its Khentei branch is limited by the Late Cenozoic troughs stretching along the southeastern border of Mongolia. On other sides, the Khangai uplift is limited by a C-shaped belt of depressions, consisting of the southeastern part of the Baikal rift zone, the Tunka and Tuva basins in the north, the Ubsunur Basin and the Great Lakes Basin in the west and the Valley of Lakes in the south. The depressions are filled with lacustrine and fluvial sediments from the Late Oligocene to the Pliocene. In the Quaternary, the Southern and Central basins of Baikal, formed no later than the Early Paleogene, became part of the Baikal rift, and other depressions were involved in the general uplift of the region. The structural paragenesis of the Khangai uplift and surrounding basins is due to the impact of the Khangai plume. Above the plume with its Khentei and Transbaikalian branches, the Cenozoic basaltic volcanism of the plume type occurred, in some places inheriting Cretaceous volcanic manifestations. Plume structural paragenesis is combined with structural paragenesis, derived from the interaction of plates and lithosphere blocks, which is expressed by active faults, but developed synchronously with plume paragenesis. The kinematics of active faults shows that the western and central parts of the region develop under conditions of transpression, and the northeastern part ‒ under conditions of extension and transtension. The Khangai plume is connected at depth with the Tibetan plume, located under the central and eastern parts of Tibet north of the Lhasa block. The Tibetan plume rises from depths of 1400–1600 km and is accompanied by thinning of the lithosphere and rise of the earth’s surface. The Khangai and Tibetan plumes represent a special category of plumes that rise from the upper part of the lower mantle and this differs from the upper mantle plumes and the African and Pacific superplumes, rising from the core-mantle boundary. A connection between the Khangai and Tibet plumes with branches of superplumes is possible, but their independent origin is also admitted.

Cenozoic source-to-sink relations between the West Kunlun Mountains and SW Tarim Basin: Evidence from an integrated provenance analysis

The tectonic evolution of West Kunlun Mountains (WKM), which is located in the NW margin of the Tibetan Plateau, plays an essential role in understanding the source-to-sink relationship between this orogenic belt and SW Tarim Basin. In this study, we conduct an integrated research incorporating detrital zircon UPb geochronology, petrography, and heavy mineral analysis of the Cenozoic synorogenic sediments from Keliyang section, SW Tarim Basin, together with the published data in the WKM forelands, and thus we can discuss the Cenozoic tectonic evolution in this activate tectonic domain. The results suggest that the NW Tibetan Plateau has experienced a four-stage evolution during the Cenozoic, characterized by three notable provenance changes occurring in the late Eocene (∼40 Ma), late Oligocene (∼26 Ma) and latest Miocene-early Pliocene, respectively. In the early Middle Eocene, the Tarim-Tajik basin was still occupied by an epicontinental sea belonging to the Neotethys Sea. Sediments in the forelands were mainly originated from erosion of the residual relief of WKM. By ∼40 Ma, the new additions of sediments from the uplifted Tianshuihai and/or South Kunlun terranes occurred, which can be attributed to the uplift of central Tibet due to the ongoing Indian northward indentation. This scenario was roughly synchronous with the final open marine seawater retreat from the Tarim Basin. We propose that the Cenozoic uplift of the Tianshuihai/South Kunlun terranes may be initiated prior to ∼40 Ma, indicating that the collision-induced deformation has propagated to the southern part of WKM by that time. Since ∼26 Ma, distal deposits increased abruptly, which can be attributed to the outward growth of the Tibetan Plateau and/or regional climate change. Finally, the shift in provenance since the latest Miocene-early Pliocene was related to the intensive uplift of WKM.

The evolution of continental rifts revealed from the numerical modeling: A case study of the Baikal rift system, Siberia

We present new results on the Late Cenozoic uplift rates at the flanks of the Baikal rift system (SE Siberia) based on the morphotectonic analysis of basin-adjacent steep-slope mountains and numerical modeling of landscape evolution. As the basic instrument of modeling, we used the CHILD software program by Dr. Greg Tucker (University of Colorado, USA) which allows reconstructing the relief evolution taking into account various orogenic processes. The model problem of the normal-fault movements was solved using the CHILD modification: adding a new tectonic option and developing some adaptations. The objects of modeling were steep normal fault escarpments with clearly defined triangular facets and without young tectonic steps. We assumed that these objects were formed at the fast-rifting stage and may thereby be considered as morphometric indicators of orogenic processes of the Late Cenozoic time. The experiment consisted of two stages. First, we determined a specific set of exogenous parameters which may be conditionally considered general for all similar escarpments of the BRS and for the Late Cenozoic era as a whole. As a reference object there was used one of segments of the Barguzin Ridge with the known uplift rate obtained by AFT. Next, we modeled some other objects from different mountains of the BRS. The results of modeling showed that the approximated Late Cenozoic uplift rate on the considered segments varies over a small range between 0.3 and 0.5 mm/yr. At the final stage, we performed morphotectonic analysis to determine probable uplift rates for steep rift shoulders.

The effects of uplift and erosion on the petroleum systems in the southwestern Barents Sea: Insights from seismic data and 2D petroleum systems modelling

In the past three decades, the hydrocarbon prospectivity has been enigmatic in the southwestern Barents Sea as gas discoveries have dominated over oil. However, more recent discoveries indicate oil potential, especially in the Polheim Platform and Hoop Complex areas. Cenozoic uplift and erosion episodes are critical because they control the duration and depth of maximum burial of source rocks and the reduction of porosity of reservoir rocks due to diagenetic processes at larger depth and increased temperatures. Modelling of interpreted horizons from the southwestern Barents Sea provide a best-fit realization of the basin-scale sedimentary filling from the post-rifting in the Jurassic until the Last Glacial Maximum. 2D basin modelling was performed across one regional seismic section crossing the southwestern Barents Sea. For calibration of the 2D model, 1D modelling was performed for a selected number of wells in the region by integrating different estimates of net apparent erosion (velocity inversion of wells, interpreted profiles and structure maps as well as from temperature and vitrinite reflectance data) in order to assess the burial, thermal and maturity history of the source rocks at various well locations as well as along the 2D profile. Simulation results show that the Upper Jurassic source rock is immature to marginal mature in the central and eastern parts of the Norwegian Barents Sea. The western part is characterised by high chargeability of traps associated with rich source kitchens and porous reservoir rocks. Although not proven by commercial discoveries, there are evidences that the Permian Ørret and the Lower-Middle Triassic basal Klappmyss and basal Kobbe shales may be important gas-prone source rocks in the eastern Norwegian Barents Sea. Consequently, the exploration must rely on the Triassic and/or Palaeozoic source rocks in the eastern area.

Landscape evolution modeling of the normal-fault scarps (Baikal rift system): new experience

The paper considers a new method for determining the quantitative parameters of the relief-forming processes characteristic of the mountainous framing of the basins of the Baikal Rift System (BRS), based on the use of a computer program for numerical simulation of the evolution of the relief CHILD. Particular emphasis was placed on the calculation of approximate values of the rate of tectonic uplift of the near-fault block structures of the Baikal rift. The novelty of the study lies in the adaptation of the CHILD program for solving fault tectonics problems, as well as in the development of a morphotectonic analysis algorithm aimed at searching for specific geomorphological objects that can be considered as uplift indicators. As a result of a series of experiments performed using radioisotope data, three-dimensional models were obtained that simulate the development of near-fault slopes at the Late Cenozoic stage of the development of the BRS, and the probable rates of vertical movements along the faults of the region were determined. It was found that the average Late Cenozoic uplift rates vary within a narrow range of 0,3–0,5 mm/yr, with higher values associated with the northern and northwestern flanks.

River inverse modeling of the late Cenozoic uplift history of the Pamir-Tian Shan orogens: Implications for aridification of Central Asia

The uplift history of the Pamir-Tian Shan orogens remains debated, and is crucial to understanding the aridification of Central Asia. To address this question, we performed inverse modeling of the westward-flowing Vakhsh River along the Alai Valley between the Pamir and Tian Shan orogens. We validated the application of this method in reconstructing uplift history of mountains with complex climatic and tectonic settings. The modeled results reveal three episodes of accelerated uplift of the Vakhsh River drainage at ca. 10–7 Ma, ca. 5 Ma, and 2–0 Ma. The late Miocene rapid uplift at rates of 0.6–0.8 mm/yr of the Vakhsh River drainage occurred at ca. 10–7 Ma. Rock uplift, coeval with compressional deformation and exhumation around the Alai Valley, was likely driven by crustal shortening during the Pamir-Tian Shan convergence. Narrowing of the Alai Valley started to impact westerly atmospheric flow, leading to incipient rain shadow responsible for emergence of desert in the proximal leeward Tarim Basin. Accelerated uplift at ca. 5 Ma and 2–0 Ma at rates of 1.0–1.4 mm/yr and 1.7–2.3 mm/yr, increased surface elevations to near modern heights (3.5–5 km) that largely blocked the westerlies, causing enhanced aridification in the Tarim Basin. Our modeling results highlight the important role of mountain building in shaping late Cenozoic climate in Central Asia.

Mesozoic−Cenozoic uplift of Qiman Tagh Range in northern Tibet Plateau, western China

The Tibetan Plateau is the highest plateau on Earth. As an ideal place to decipher the intracontinental deformation mechanisms, the Tibetan Plateau has become a focus of Cenozoic geological studies. The surface uplift history of the Tibetan Plateau can help us to better understand continental collision and processes ranging from global cooling to the onset of the Asian monsoon. Although a lot of research has been done over the years, the mechanism and timing of uplift of the Tibetan Plateau, especially the northern part, continue to be debated. To address how the Tibetan Plateau developed, a better understanding of the uplift and deformation history is needed. The Qiman Tagh Range lies on the northeastern margin of the Tibetan Plateau. Knowing what led to the exhumation of the Qiman Tagh Range could help us to constrain the tectonic evolution of the northern boundaries of the Tibetan Plateau. Here, we present new apatite fission-track data and the thermal history for the north Qiman Tagh Range. The thermal history modeling indicates that the Qiman Tagh Range experienced a four-stage cooling history (i.e., at ca. 230 Ma, 130−90 Ma, ca. 35 Ma, and 20/10−0 Ma). The results reveal that the initial exhumation of the Qiman Tagh Range occurred in the Middle Triassic due to the collision between the western Qiangtang and eastern Qiangtang terranes and the northward colliding and collaging of the Kumukuri microcontinent with the south Qiman Tagh Terrane. The rapid exhumation during the Cretaceous resulted from the collisions between the Lhasa and Qiangtang terranes. The Cenozoic exhumation may be related to the far-field stress effect of the India-Asia collision. Based on our new data, together with tectonic studies around the Qaidam Basin, we reconstructed the big Paleo-Qaidam Basin as it was during late Mesozoic and early Cenozoic time. The Mesozoic uplift of the Qiman Tagh Range was not high enough to form topographical isolation, but the rapid uplift of the Qiman Tagh at ca. 35 Ma completely separated the Kumukol Basin to the south from the Qaidam Basin to the north. The Qiman Tagh Range has experienced an acceleration of uplift since the Miocene to present, which formed the current basin-range landform. The study constrains the uplift history of the northern Tibetan Plateau and helps us to better understand its growth mechanism.

Crustal structure and geodynamics of the eastern Qilian orogenic belt, NE margin of the Qinghai-Tibet plateau, revealed by teleseismic receiver function

The eastern segment of the Qilian orogenic belt, comprising the Linxia block and Longzhong block, is at the Qinghai–Tibet Plateau’s northeastern margin. The area has experienced multiple tectonic events, including closure of the Qilian Ocean, convergence of the North China block and Qilian terrane, and collision of the Indian and Eurasian plates, forming a complex tectonic framework. To investigate the area’s geological evolution and the suture’s current location between the blocks, we used 3-year data recorded by 33 portable ChinArray II broadband stations (2013–2016). Using three teleseismic P-wave receiver function methods, H-κ stacking and common conversion point stacking (CCP), crustal structure, Poisson’s ratio, and Moho morphology were obtained at 33 stations. The results are described as follows: 1) The Maxianshan fault is an important boundary fault that divides the Linxia block and Longzhong block. The Linxia block’s layered crustal structure is obvious, and there is a low-velocity anomaly in the middle and lower crust, which may contain saline fluid and has Japanese-type island arc characteristics. 2) The layered structure of the Longzhong block’s upper crust is significant, while the middle and lower crust’s layered structure is weak with weak low-velocity characteristics and oceanic-island basaltic crust characteristics. The Longzhong block may have originally been formed by Mariana-type island arcs. 3) The Conrad interface and Moho lateral variation in the Ordos block’s southwestern margin are weak, showing stable craton characteristics. 4) Our results show that the Maxianshan fault cuts through the Earth’s crust and is a continuous west-dipping negative seismic phase in the Common Conversion Point section. The fault zone is the suture line between the Linxia block and Longzhong block. 5) The middle and upper crust of the Liupanshan tectonic belt is thrust upwards on the Ordos block’s southwestern margin, providing deep structural evidence of the Cenozoic uplift of the Liupanshan structural belt.