The Experts below are selected from a list of 30018 Experts worldwide ranked by ideXlab platform
Michel Faure - One of the best experts on this subject based on the ideXlab platform.
-
sedimentological and geochronological constraints on the Carboniferous evolution of central inner mongolia southeastern central asian orogenic belt inland sea deposition in a post orogenic setting
Gondwana Research, 2016Co-Authors: Michel Faure, Pan Zhao, Bei Xu, Qinlong Tong, Yan ChenAbstract:Abstract Sedimentological and geochronological analyses were performed on Carboniferous strata from central Inner Mongolia (China) to determine the tectonic setting of the southeastern Central Asian Orogenic Belt (CAOB). Sedimentological analyses indicate that the widespread Late Carboniferous strata in central Inner Mongolia were dominated by shallow marine clastic-carbonate deposition with basal conglomerate above the Precambrian basement and Early Paleozoic orogenic belts. Based on lithological comparison and fossil similarity, five sedimentary stages were used to represent the Carboniferous deposition. The depositional stages include, from bottom to top, 1) basal molassic, 2) first carbonate platform, 3) terrigenous with coeval intraplate volcanism, 4) second carbonate platform, and 5) post-carbonate terrigenous. These five stages provide evidence for an extensive transgression in central Inner Mongolia during the Late Carboniferous. Detrital zircon geochronological studies from five samples yielded five main age populations: ~ 310 Ma, ~ 350 Ma, 400–450 Ma, 800–1200 Ma and some Meso-Proterozoic to Neoarchean grains. The detrital zircon geochronological studies indicate that the provenances for these Late Carboniferous strata were mainly local magmatic rocks (Early Paleozoic arc magmatic rocks and Carboniferous intrusions) with subordinate input of Precambrian basement. Combining our sedimentological and provenance analyses with previous fossil comparison and paleomagnetic reconstruction, an inland sea was perceived to be the main paleogeographic feature for central Inner Mongolia during the Late Carboniferous. The inland sea developed on a welded continent after the collision between North China Craton and its northern blocks.
-
from oblique accretion to transpression in the evolution of the altaid collage new insights from west junggar northwestern china
Gondwana Research, 2012Co-Authors: Flavien Choulet, Dominique Cluzel, Michel Faure, Yan Chen, Wei Lin, Bo WangAbstract:Abstract Along active margins, tectonic features that develop in response to plate convergence are strongly controlled by subduction zone geometry. In West Junggar, a segment of the giant Palaeozoic collage of Central Asia, the West Karamay Unit represents a Carboniferous accretionary complex composed of fore-arc sedimentary rocks and ophiolitic melanges. The occurrence of quasi-synchronous upright folds and folds with vertical axes suggests that transpression plays a significant role in the tectonic evolution of the West Junggar. Latest Carboniferous (ca. 300 Ma) alkaline plutons postdate this early phase of folding, which was synchronous with accretion of the Carboniferous complex. The Permian Dalabute sinistral fault overprints Carboniferous ductile shearing and split the West Karamay Unit ca. 100 km apart. Oblique convergence may have been provoked by the buckling of the Kazakh orocline and relative rotations between its segments. Depending upon the shape of the convergence zone, either upright folds and fold with vertical axes, or alternatively, strike–slip brittle faults developed in response to strain partitioning. Sinistral brittle faulting may account for the lateral imbrication of units in the West Junggar accretionary complex.
-
geochemical constraints on Carboniferous volcanic rocks of the yili block xinjiang nw china implication for the tectonic evolution of western tianshan
Journal of Asian Earth Sciences, 2007Co-Authors: Bo Wang, Dominique Cluzel, Michel Faure, Jacques CharvetAbstract:The Yili Block is important for understanding the Late Paleozoic geodynamic evolution of Central Asia. It is bounded to the north by the Northern Tianshan Carboniferous flysch and ophiolitic melange. The center of the Block is dominated by Carboniferous sedimentary rocks with intercalation of volcanic rocks. Petrological and geochemical features of these Carboniferous volcanic rocks show that: (1) they belong to the calc-alkaline series, (2) they display prominent Nb–Ta negative anomalies consistent with subduction-related magmas, and (3) HFSE-based discriminations place these volcanic rocks in the field of continental arcs. The depositional evolution of the sedimentary series shows evidence for Carboniferous sedimentation in a basin instead of rifting as previously proposed. All these evidences, together with the occurrence of contemporaneous turbidites and ophiolitic melange along the northern boundary of the Yili Block, allow us to infer that the northern border of the Yili Block was a continental active margin during the Carboniferous. The Late Carboniferous southward subduction that finally closed the Late Devonian to Early Carboniferous North Tianshan oceanic basin was followed by Permian–Mesozoic polyphase transcurrent faulting.
Pan Zhao - One of the best experts on this subject based on the ideXlab platform.
-
a rift system in southeastern central asian orogenic belt constraint from sedimentological geochronological and geochemical investigations of the late Carboniferous early permian strata in northern inner mongolia china
Gondwana Research, 2017Co-Authors: Pan Zhao, Chenhao ZhangAbstract:Abstract The Late Carboniferous-Early Permian is the most controversial period for the tectonic evolution of the southeastern Central Asian Orogenic Belt (CAOB). In this study, we performed sedimentological and detrital zircon dating on the clastic sediments, as well as zircon U-Pb age and geochemical analysis on the rhyolitic rocks of the Late Carboniferous-Early Permian strata from northern Inner Mongolia (China). The sedimentological analysis showed that the Late Carboniferous-Early Permian sediments are composed of continental clastic and volcanic rocks with basal conglomerate overlying the Devonian strata. The detrital zircon study revealed three age peaks at ~ 300 Ma, ~ 440 Ma and ~ 530 Ma, indicating that the clastic rocks derived from Paleozoic magmatic rocks and pre-Carboniferous sediments from northern Inner Mongolia. The age data revealed that rhyolitic rocks from northern Inner Mongolia extruded in two stages at Late Carboniferous and latest Carboniferous-Early Permian. The Late Carboniferous rhyolites show I- to A-type granitic affinities whereas the latest Carboniferous-Early Permian rhyolites have A-type granitic characteristics. The difference suggests a transition of tectonic setting from post-collisional extension to intraplate rift. The Late Carboniferous-Early Permian strata from northern Inner Mongolia and South Mongolia show similar sedimentary facies, detrital zircon age distribution and geochemistry features, hence they were probably deposited in the same tectonic setting. A unified block was finally proposed in northern Inner Mongolia and South Mongolia, where a rift system provided an intra-continental sedimentary basin and induced intense syn-rift magmatic activities. The intra-continental basin and syn-rift magmatism indicate that the Xing'an-Airgin Sum, Songliao-Hunshandake and South Mongolia Blocks in southeastern CAOB have been welded into a single continental block before the Late Carboniferous.
-
sedimentological and geochronological constraints on the Carboniferous evolution of central inner mongolia southeastern central asian orogenic belt inland sea deposition in a post orogenic setting
Gondwana Research, 2016Co-Authors: Michel Faure, Pan Zhao, Bei Xu, Qinlong Tong, Yan ChenAbstract:Abstract Sedimentological and geochronological analyses were performed on Carboniferous strata from central Inner Mongolia (China) to determine the tectonic setting of the southeastern Central Asian Orogenic Belt (CAOB). Sedimentological analyses indicate that the widespread Late Carboniferous strata in central Inner Mongolia were dominated by shallow marine clastic-carbonate deposition with basal conglomerate above the Precambrian basement and Early Paleozoic orogenic belts. Based on lithological comparison and fossil similarity, five sedimentary stages were used to represent the Carboniferous deposition. The depositional stages include, from bottom to top, 1) basal molassic, 2) first carbonate platform, 3) terrigenous with coeval intraplate volcanism, 4) second carbonate platform, and 5) post-carbonate terrigenous. These five stages provide evidence for an extensive transgression in central Inner Mongolia during the Late Carboniferous. Detrital zircon geochronological studies from five samples yielded five main age populations: ~ 310 Ma, ~ 350 Ma, 400–450 Ma, 800–1200 Ma and some Meso-Proterozoic to Neoarchean grains. The detrital zircon geochronological studies indicate that the provenances for these Late Carboniferous strata were mainly local magmatic rocks (Early Paleozoic arc magmatic rocks and Carboniferous intrusions) with subordinate input of Precambrian basement. Combining our sedimentological and provenance analyses with previous fossil comparison and paleomagnetic reconstruction, an inland sea was perceived to be the main paleogeographic feature for central Inner Mongolia during the Late Carboniferous. The inland sea developed on a welded continent after the collision between North China Craton and its northern blocks.
Huayun Tang - One of the best experts on this subject based on the ideXlab platform.
-
geochemistry and geochronology of Carboniferous volcanic rocks in the eastern junggar terrane nw china implication for a tectonic transition
Gondwana Research, 2012Co-Authors: J P Zheng, W L Griffin, Junhong Zhao, Huayun Tang, Xiangyang LinAbstract:The Carboniferous tectonic setting of the Junggar terrane, northern Xinjiang, NW China, has long been a matter of debate. Voluminous Carboniferous volcanic rocks are widely distributed in the Karamaili area, the southern part of the eastern Junggar terrane. Early Carboniferous rocks comprise basalts and basaltic andesites, with enrichment of LREE and LILE and depletion of HFSE, and uniformly high eNd(t) (+ 3.7 to + 4.0). Late Carboniferous rocks consist of basalts, basaltic andesites, rhyolites and minor dacites, and can be subdivided into basic and felsic groups. The basic rocks are depleted in HFSE, and show variable high eNd(t) (+ 4.8 to + 6.9). They have higher Cr and Ni and lower Na2O, U and Th contents than early Carboniferous basic rocks. The felsic rocks show A-type affinity, with typical enrichment of alkalis, LREE and HFSE and strong depletion in Ba, Sr, Eu and Ti. They have high values of eNd(t) and zircon eHf(t) (+ 11.6 to + 17.9). New LA-ICPMS zircon U–Pb analyses constrain their emplacement to late Carboniferous time (306.5–314.3 Ma). The Carboniferous basic rocks show negative Zr-Hf anomalies and low Th/Ce (< 0.07) and Th/La (0.06–0.16), excluding significant crustal contamination during magma evolution. They have low La/Ba (0.03–0.12), Ce/Y (< 3) and (Tb/Yb)N (< 2) and variable Ba/Th (28–318) and Ba/La (3.1–34), suggesting that they were derived from a main spinel with minor garnet lherzolite mantle source metasomatized by slab-derived fluids. The late Carboniferous felsic rocks were produced when upwelling asthenosphere triggered partial melting of juvenile lower crust. The early Carboniferous volcanism occurred in an island-arc setting related to the southward subduction of the Paleo-Junggar Ocean plate, whereas the late Carboniferous rocks erupted in a post-collisional extensional setting. Thus, a rapid tectonic transition from arc to post-collisional extension may have occurred between early and late Carboniferous, and probably resulted from slab break-off or lithospheric delamination.
-
geochemistry and geochronology of Carboniferous volcanic rocks in the eastern junggar terrane nw china implication for a tectonic transition
Gondwana Research, 2012Co-Authors: W L Griffin, Junhong Zhao, Yuping Su, Jianping Zheng, Huayun TangAbstract:Abstract The Carboniferous tectonic setting of the Junggar terrane, northern Xinjiang, NW China, has long been a matter of debate. Voluminous Carboniferous volcanic rocks are widely distributed in the Karamaili area, the southern part of the eastern Junggar terrane. Early Carboniferous rocks comprise basalts and basaltic andesites, with enrichment of LREE and LILE and depletion of HFSE, and uniformly high eNd(t) (+ 3.7 to + 4.0). Late Carboniferous rocks consist of basalts, basaltic andesites, rhyolites and minor dacites, and can be subdivided into basic and felsic groups. The basic rocks are depleted in HFSE, and show variable high eNd(t) (+ 4.8 to + 6.9). They have higher Cr and Ni and lower Na2O, U and Th contents than early Carboniferous basic rocks. The felsic rocks show A-type affinity, with typical enrichment of alkalis, LREE and HFSE and strong depletion in Ba, Sr, Eu and Ti. They have high values of eNd(t) and zircon eHf(t) (+ 11.6 to + 17.9). New LA-ICPMS zircon U–Pb analyses constrain their emplacement to late Carboniferous time (306.5–314.3 Ma). The Carboniferous basic rocks show negative Zr-Hf anomalies and low Th/Ce (
Yuping Su - One of the best experts on this subject based on the ideXlab platform.
-
geochemistry and geochronology of Carboniferous volcanic rocks in the eastern junggar terrane nw china implication for a tectonic transition
Gondwana Research, 2012Co-Authors: W L Griffin, Junhong Zhao, Yuping Su, Jianping Zheng, Huayun TangAbstract:Abstract The Carboniferous tectonic setting of the Junggar terrane, northern Xinjiang, NW China, has long been a matter of debate. Voluminous Carboniferous volcanic rocks are widely distributed in the Karamaili area, the southern part of the eastern Junggar terrane. Early Carboniferous rocks comprise basalts and basaltic andesites, with enrichment of LREE and LILE and depletion of HFSE, and uniformly high eNd(t) (+ 3.7 to + 4.0). Late Carboniferous rocks consist of basalts, basaltic andesites, rhyolites and minor dacites, and can be subdivided into basic and felsic groups. The basic rocks are depleted in HFSE, and show variable high eNd(t) (+ 4.8 to + 6.9). They have higher Cr and Ni and lower Na2O, U and Th contents than early Carboniferous basic rocks. The felsic rocks show A-type affinity, with typical enrichment of alkalis, LREE and HFSE and strong depletion in Ba, Sr, Eu and Ti. They have high values of eNd(t) and zircon eHf(t) (+ 11.6 to + 17.9). New LA-ICPMS zircon U–Pb analyses constrain their emplacement to late Carboniferous time (306.5–314.3 Ma). The Carboniferous basic rocks show negative Zr-Hf anomalies and low Th/Ce (
J P Zheng - One of the best experts on this subject based on the ideXlab platform.
-
geochemistry and geochronology of Carboniferous volcanic rocks in the eastern junggar terrane nw china implication for a tectonic transition
Gondwana Research, 2012Co-Authors: J P Zheng, W L Griffin, Junhong Zhao, Huayun Tang, Xiangyang LinAbstract:The Carboniferous tectonic setting of the Junggar terrane, northern Xinjiang, NW China, has long been a matter of debate. Voluminous Carboniferous volcanic rocks are widely distributed in the Karamaili area, the southern part of the eastern Junggar terrane. Early Carboniferous rocks comprise basalts and basaltic andesites, with enrichment of LREE and LILE and depletion of HFSE, and uniformly high eNd(t) (+ 3.7 to + 4.0). Late Carboniferous rocks consist of basalts, basaltic andesites, rhyolites and minor dacites, and can be subdivided into basic and felsic groups. The basic rocks are depleted in HFSE, and show variable high eNd(t) (+ 4.8 to + 6.9). They have higher Cr and Ni and lower Na2O, U and Th contents than early Carboniferous basic rocks. The felsic rocks show A-type affinity, with typical enrichment of alkalis, LREE and HFSE and strong depletion in Ba, Sr, Eu and Ti. They have high values of eNd(t) and zircon eHf(t) (+ 11.6 to + 17.9). New LA-ICPMS zircon U–Pb analyses constrain their emplacement to late Carboniferous time (306.5–314.3 Ma). The Carboniferous basic rocks show negative Zr-Hf anomalies and low Th/Ce (< 0.07) and Th/La (0.06–0.16), excluding significant crustal contamination during magma evolution. They have low La/Ba (0.03–0.12), Ce/Y (< 3) and (Tb/Yb)N (< 2) and variable Ba/Th (28–318) and Ba/La (3.1–34), suggesting that they were derived from a main spinel with minor garnet lherzolite mantle source metasomatized by slab-derived fluids. The late Carboniferous felsic rocks were produced when upwelling asthenosphere triggered partial melting of juvenile lower crust. The early Carboniferous volcanism occurred in an island-arc setting related to the southward subduction of the Paleo-Junggar Ocean plate, whereas the late Carboniferous rocks erupted in a post-collisional extensional setting. Thus, a rapid tectonic transition from arc to post-collisional extension may have occurred between early and late Carboniferous, and probably resulted from slab break-off or lithospheric delamination.