Tectonic Difference between the Qaidam Basin and the Eastern Kunlun Shan: Insight from Buffer Analysis of the Earthquakes and Faults in the North Tibet

AbstractLiving Caprini are dominant bovids in the pan-Tibetan area that are strongly adapted to dry steppe and high-mountain meadow habitats. Some taxa with Holarctic distributions, e.g., Ovis Linnaeus, 1758, were thought to originate on the Tibetan Plateau and subsequently dispersed elsewhere, which was depicted as an ‘out of Tibet’ story. However, except for some information on a stem caprine assemblage from the Qaidam Basin, the early evolution of Caprini around the Tibetan Plateau is poorly known. Here, we report new material of Olonbulukia tsaidamensis Bohlin, 1937, which was a member of this stem caprine assemblage, from the Wuzhong region, northern China, confirming the similarity of the Wuzhong Fauna and ‘Qaidam Fauna.’ Based on a biometric study of horncores from the ‘Qaidam’ and Wuzhong faunas, we recognize six taxa from this stem caprine assemblage: O. tsaidamensis, O. sp., Qurliqnoria cheni Bohlin, 1937, Tossunnoria pseudibex Bohlin, 1937, ?Protoryx cf. P. enanus Köhler, 1987, and cf. Pachytragus sp. Among these taxa, Q. cheni and T. pseudibex are probably related to some extant Tibetan endemic species, e.g., the Tibetan antelope, Pantholops hodgsonii (Abel, 1826), and the Himalayan tahr, Hemitragus jemlahicus (Smith, 1826). Others might be ancestral to the Turolian caprine assemblages and even possibly gave rise to the extant Caprina. This work reveals an early radiation of stem caprines along the northern side of the rising Tibetan Plateau and indicates a mixed pattern of pan-Tibetan stem caprine evolution prior to their dispersal out of the Tibetan Plateau.

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Fluid inclusion evidence for boiling process of petroleum fluid in the north Qaidam Basin (NW China)

Geochimica et Cosmochimica Acta ◽

10.1016/j.gca.2006.06.744 ◽

2006 ◽

Vol 70 (18) ◽

pp. A368

Author(s):

Y.T. Liu ◽

K. Hu ◽

J. Cao ◽

S.Y. Yang ◽

L.L. Yan ◽

...

Keyword(s):

Fluid Inclusion ◽

Qaidam Basin ◽

Nw China ◽

The North ◽

Boiling Process ◽

North Qaidam ◽

Petroleum Fluid

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Intensified Late Miocene Deformation in the Northern Qaidam Basin, Northern Tibetan Plateau, Constrained by Apatite Fission-Track Thermochronology

Frontiers in Earth Science ◽

10.3389/feart.2021.750993 ◽

2021 ◽

Vol 9 ◽

Author(s):

Pengju He ◽

Chunhui Song ◽

Yadong Wang ◽

Yihu Zhang ◽

Wenqi Chen ◽

...

Keyword(s):

Tibetan Plateau ◽

Late Miocene ◽

Fission Track ◽

Qaidam Basin ◽

Thrust Belt ◽

Apatite Fission Track ◽

The North ◽

Northern Tibetan Plateau ◽

Fission Track Thermochronology ◽

North Qaidam

The Cenozoic tectonic evolution of the North Qaidam-Qilian Shan fold-thrust belt in the northern Tibetan Plateau is important to understanding the tectonic rejuvenation of orogeny and growth of the plateau. However, the deformation processes in this region remain controversial. This study presents new apatite fission track (AFT) data from Paleogene strata in the northern Qaidam Basin to investigate the time of deformation in this site. Thermal modeling of these partially annealed detrital AFT ages shows a thermal history with a noticeable transition from heating to cooling after ∼10 Ma. This transition is attributed to the intensified thrusting and folding of the northern Qaidam Basin since ∼10 Ma. Integrated with published tectonics and thermochronology results, we suggest the North Qaidam-Qilian Shan fold-thrust belt experienced prevailing tectonism since the late Miocene.

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Jurassic Provenance System and Its Geological Implication in Altyn Piedmont, Qaidam Basin

Lithosphere ◽

10.2113/2021/7705469 ◽

2021 ◽

Vol 2021 (Special 1) ◽

Author(s):

X. Zeng ◽

Q. Cao ◽

B. Wang ◽

C. Hu ◽

J. X. Tian ◽

...

Keyword(s):

Spatial Distribution ◽

Qaidam Basin ◽

Middle Part ◽

Source Rocks ◽

Fault System ◽

Late Triassic ◽

Systematic Research ◽

The North ◽

East Kunlun ◽

Jurassic Formation

Abstract A petroleum system originating from Jurassic source rocks exists in Altyn piedmont. However, the Jurassic formation in this system is deformed by Yanshan-Himalayan tectonic movement, and related studies about its spatial distribution and sedimentary system are still highly controversial. In general, a systematic research on the provenance system helps precisely restoring the prototype basin. Based on the methods of seismic characterization, sedimentary analysis, and detrital zircon U-Pb dating (samples from several Altyn piedmont outcrops), this paper studied the provenances of Jurassic formation in Altyn piedmont and characterized their distribution from different aspects: (1) Lacustrine rift basin developed in the study area at early Jurassic, while the formation showed a saucer shape with its thickness decreasing and vanishing towards the center of the basin in the middle Jurassic; in summary, the Jurassic formation in Altyn piedmont could be divided into several parts due to their different characteristics in different periods. (2) The south part of the Jurassic deposition (south of Qingshuigou) could come from the east Kunlun terrain; the middle part (Yueya mountain to Dongping area) however could be from several provenances, including the east Kunlun terrain, the surrounding plutons, and the Altyn fault; the north part (Niudong to north Lenghu area) is mainly related to the Altyn fault. (3) The Altyn fault, a regional fault system containing several strike-slip faults, is highly active since late Triassic and controls the current spatial distribution of the Jurassic formation; the faulted area in the piedmont could be separated into several parts with several different sources. (4) Compared to the southern and middle parts, the northern Jurassic deposition is relatively flat and contains wider and thicker source rock beds, which makes this area an important gas exploration target.

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Active Faulting of Landforms along the Tuosuhu-Maoniushan Fault and Its Seismotectonic Implications in Eastern Qaidam Basin, China

Seismological Research Letters ◽

10.1785/0220210110 ◽

2022 ◽

Author(s):

Guihua Chen ◽

Xun Zeng ◽

Zhongwu Li ◽

Xiwei Xu

Keyword(s):

Late Quaternary ◽

Qaidam Basin ◽

Slip Rate ◽

Northern Margin ◽

The North ◽

Fold And Thrust Belt ◽

Field Investigations ◽

High Resolution Satellite Images ◽

Geomorphic Features ◽

Tectonic Belt

Abstract The fold-and-thrust belt along the northern margin of the Qaidam basin is a typical active tectonic belt located in the northeast Tibetan Plateau. This belt is at a high risk of strong earthquakes with magnitudes larger than 6, as shown by multiple recorded events during 1962–2009. The lack of detailed late Quaternary surficial faulting data and systematic seismotectonic studies has posed difficulties in properly assessing the seismic risks and understanding the ongoing geodynamics in this region. In this study, we mapped the geomorphic features and fault traces from high-resolution satellite images and field investigations of the Tuosuhu-Maoniushan fault (TMF). Field photogrammetry was conducted to obtain deformation measurements using a DJI M300 real-time kinematic (RTK) drone. The TMF displaces the Holocene and late Pleistocene alluvial terraces in the eastern Qaidam basin. This fault dips to the south in the west and central segments (as a boundary of the Denan depression) and to the north in the eastern segment along the piedmont of the Maoniushan Mountains. The vertical slip rate is estimated to be 0.37 ± 0.08 mm/yr, which is similar to that of the active southern Zongwulongshan fault. By integrating our investigations with the previously published studies on deep structures and Cenozoic geology of the region, we propose a deep-seated thrust model for the seismotectonics of the northern margin of the Qaidam basin. The Aimunike, Tuosuhu-Maoniushan, southern Zongwulongshan, and Zongwulong faults, along with many folds, form an active compressional zone. The complex across-strike structures and along-strike segmentation could facilitate the release of strain through earthquakes of magnitude 6–7 in this broad seismotectonics belt, rather than through strong surface-rupturing events resulting from a single mature large fault.

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New Ediacara-type fossils and late Ediacaran stratigraphy from the northern Qaidam Basin (China): Paleogeographic implications

Geology ◽

10.1130/g48842.1 ◽

2021 ◽

Author(s):

Ke Pang ◽

Chengxi Wu ◽

Yunpeng Sun ◽

Qing Ouyang ◽

Xunlai Yuan ◽

...

Keyword(s):

North China ◽

Qaidam Basin ◽

Equatorial Region ◽

Northwestern China ◽

Cambrian Explosion ◽

North China Block ◽

The North ◽

Time Period ◽

Depositional Age ◽

Almost All

Ediacara-type macrofossils characterize the late Ediacaran Period and are pivotal in understanding the early evolution of animals on the eve of the Cambrian explosion and useful in late Ediacaran biostratigraphy. They have been discovered on almost all major paleocontinents, except the North China and Tarim blocks, as well as on a series of northwestwest–oriented cratonic fragments between the two blocks, including the Olongbuluke terrane of the Qaidam block, where the terminal Ediacaran successions developed. We report a newly discovered terminal Ediacaran biotic assemblage, the Quanjishan assemblage, containing Ediacara-type fossils from the Zhoujieshan Formation of the Quanji Group in the Olongbuluke terrane, Qaidam Basin, northwestern China. The Quanjishan assemblage is dominated by the non-biomineralized tubular taxon Shaanxilithes, which has the potential to be a terminal Ediacaran index fossil, and by the iconic frondose rangeomorph Charnia, which represents the only unambiguous Ediacara-type fossil discovered in northwestern China. The co-occurrence of Charnia and Shaanxilithes from the Quanjishan assemblage likely constrains the depositional age of the Zhoujieshan Formation to be terminal Ediacaran (ca. 550–539 Ma) and the immediately underlying Hongtiegou diamictites to be late Ediacaran, probably representing post-Gaskiers glacial deposition. The occurrence of post-Gaskiers Ediacaran glaciation and similarities between the late Ediacaran–early Paleozoic lithostratigraphic and biostratigraphic sequences in the Olongbuluke terrane of the Qaidam block and the North China block suggest that these two blocks may have been located close to each other during this time period, and situated in the middle to high latitudes instead of the equatorial region.

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