Shunhu Yang

Chinese Academy of Sciences | CAS · Institute of Geology and Geophysics

The Cambrian Explosion (540-515 Ma ago) is arguably the most significant evolutionary transition after the origin of life. A variety of environmental perturbations including rising oxygen levels, changes in ocean chemistry and increased bio-essential elements have been correlated to this rapid faunal diversification. Anomalously high weathering flu...

Subduction initiation is a pivotal process in plate tectonics. Models of subduction initiation include the collapse of passive margins, oceanic transform faults, inversion of oceanic core complexes, and ridge failure but have ignored the potential effects of continental crust relicts within the oceanic crust. In this paper, we explore the role of m...

The immense Central Asian Orogenic Belt (CAOB) records the transition from the Pan-Rodinian Mirovoi Ocean to the Paleo-Asian Ocean, but the final closure of the Mirovoi Ocean remains unexplored. Here we document two new eclogite occurrences, located between CAOB microcontinents and the Ediacaran–Cambrian island arc in Mongolia. Pseudosection modeli...

As the youngest segment of the Central Asian Orogenic Belt, the Mongol-Okhotsk Belt is critical for understanding the final amalgamation of East Asia. However, whether the Mongol-Okhotsk Ocean closed in a scissor-like manner remains controversial, in part because the spatial and temporal change of the subduction-related magmatic records are not wel...

The Late Paleozoic–Mesozoic Mongol–Okhotsk Ocean was the latest ocean basin witnessing the final amalgamation of East Asia. However, the kinematic evolution and geodynamics of Mongol–Okhotsk's subduction initiation remain enigmatic mainly due to the lack of appropriate studies of its ophiolitic records. Here, we report for the first time a subducti...

The now-extinct Palaeozoic to Mesozoic Mongol–Okhotsk Ocean is evidenced by the Mongol–Okhotsk suture, which stretches from central Mongolia to the Sea of Okhotsk. The geodynamics of southward subduction of the Mongol–Okhotsk Ocean remain enigmatic, especially whether the subduction began during the Carboniferous is highly debated. In this paper we...

The Cambrian Explosion (541-515 Myr ago) is arguably the most significant evolutionary transition after the origin of life1-2. A variety of environmental perturbations have been correlated to this rapid animal species diversification1-3. Increased weathering fluxes from the continents to the oceans are hypothesized to cause these perturbations4-6,...

Late Carboniferous to Permian granitoids in South Mongolia records the processes from collision to post-orogenic extension for the southern Central Asian Orogenic Belt (CAOB). Systematic geochemical (major, trace elements, and Sr-Nd-Hf isotope) and geochronological (zircon U-Pb age) analyses on granitoids provide constraints on the post-subduction...

The Mongol-Okhotsk orogenic belt (MOB) is considered to be the youngest division of the huge Central Asian Orogenic Belt, but its origin and evolution are still enigmatic. To better understand the history of the MOB, we conducted U-Pb geochronological analyses of detrital-zircon grains from Neoproterozoic-Paleozoic sedimentary sequences as well as...

Mashhad ultramafic volcanic rocks, located within the Paleo‐Tethys suture zone in the north‐eastern Iran, are composed mainly of komatiitic rocks with interbedded picrobasalts. The Mashhad komatiitic rocks are characterized by low Al2O3/TiO2 ratios (9.85–11.44) and depleted HREE patterns with slightly high (Gd/Yb)N ratios (1.48–1.74), similar to th...

The southern Central Asian Orogenic Belt (CAOB) in South Mongolia consists of continental fragments sutured together by Paleozoic arc magmatism generated by the closing of the Paleo-Asian Ocean (PAO). Controversy persists regarding the timing and position of the final amalgamation of the Altai and Tianshan orogenic belts. This paper presents zircon...

The ophiolites that occur as inliers among the Late Paleozoic formations in the Middle Gobi area are crucial for understanding the tectonic evolution of South Mongolia. In this paper, we conducted detailed studies on the Namdain hundy ophiolite to provide some constraints on the Early Paleozoic evolution of the Middle Gobi region in Mongolia. The o...

The Olzit volcanism in Middle Mongolia comprises a bimodal suite of basalts and peralkaline rhyolites adjacent to the Main Mongolia Lineament. The basalts are characterized by enrichment in LILE and LREE, and depletion in HFSE with typical Sr-Nd isotopic signatures (εNd(t)=-2.50 to -0.38 and (87Sr/86Sr)i=0.7058 to 0.7063), indicating they were like...

SIMS zircon U-Pb dating, geochemical and Sr-Nd isotopic data are presented for the Late Paleozoic volcanic rocks from Tost area in Mongolia, the southern portion of the Central Asian Orogenic Belt (CAOB). The Tost volcanic rocks show a bimodal feature characterized by a mafic member of basalt and a felsic component of rhyolite, which are temporally...

The Kherlen terrane, which contains the Kherlen ophiolitic complex, is located between two Precambrian continental blocks in the northeastern Mongolia. We present new geochemical and SHRIMP zircon U-Pb data for the Kherlen ophiolitic complex and for granitic plutons intruding the complex, providing constraints on the regional evolution in early Pal...

Late Paleozoic subduction–accretion complexes occur widely in Middle Gobi area and provide a good opportunity for unraveling the Paleozoic tectonic evolution of South Mongolia. The magmatic rocks in the Tsavchir hudug district mainly consist of rhyolites and volcaniclastic rocks. The rhyolites show enrichment in LREE and LILE and negative Nb, Ta an...

Although large earthquakes can have significant impacts on the geomorphology of mountain rivers, the consequences of such impacts remain poorly understood. The Ms 8.0 Wenchuan earthquake of 12 May 2008 created knickpoints (waterfalls) in the river systems of the Longmen Shan, eastern Tibet Plateau, in addition to numerous landslides along rivers. I...

In tectonically active mountain belts, earthquakes can contribute to surface erosion by generating large-scale landslides. This study focuses on establishing the relationship between surface erosion caused by the earthquake-induced landslides and landscape evolution of the Longmen Shan, eastern Tibet Plateau. The inventory of landslides related to...

Numerous small dismembered ophiolite fragments occur in South Mongolia, but they are very poorly studied. The lack of age data and geochemical analysis hampers our understanding of the Paleozoic tectonic evolution of the region. We conducted detailed studies on the Manlay ophiolitic complex and Huree volcanic rocks south of the Main Mongolian Linea...

In recent years, many porphyry-type Cu deposits have been found in Mongolian Gobi-Tianshan and in Chinese Beishan and Tianshan. This paper summarizes geological characteristics and metallogenic age data of typical porphyry-type deposits in these areas and suggests that the deposits were mainly formed during Devonian-Carboniferous. Meanwhile, most o...

The Gobi-Tianshan Fault System (GTFS) extending over 700 km long is one of the largest strike-slip faults in the Central Asia Orogenic Belt (CAOB), which was considered to accommodate the eastward extrusion of Tibet. On the basis of tectono-geomorphic interpretation of satellite remote sensing images along GTFS, this study aims to document the Late...

SHRIMP U-Pb data of zircons from the strongly greisenized granite at the Khar Morit W-Sn ore deposit in Gobi Tianshan of South Mongolia shows that the emplacement age of granite intrusion is (214±3) Ma, which indicates that the W-Sn mineralization of the deposit took place during Triassic in Early Mesozoic. According to the comprehensive analysis o...

Longling-Ruili Fault zone(LRF)is located at the boundary between China and Burma, striking in northeast direction for about 135km and controling the formation and evolution of Longling, Luxi, Zhefang and Ruili Basins. This study utilizes the high-resolution remote sensing data, such as ALOS and ASTER and SRTM digital elevation model data in combina...

Kumukol Basin, located at the north margin of the Tibetan Plateau, is separated from the Qaidam Basin by the Qimantag range geographically. It is the transitional region between the Tibetan Plateau and Qaidam Basin, and also the leading edge of the growing main body of the plateau. Nowadays, East Kunlun Fault and Altyn Tagh Fault, two significant s...

Great earthquakes play an active role in geomorphic evolution of orogenic belts, and the time response of river evacuation of landslide mass induced by great earthquakes is a key aspect in the field of tectonic geomorphology. Here we quantitatively estimate the time response of unloading of the coseimsic landslide mass and sediments due to the 2008...