Petrology and P–T path of high-pressure granulite from the Dulan area, North Qaidam Mountains, northwestern China

Yu, Shengyao; Zhang, Jianxin; Real, Pablo García del

doi:10.1016/j.jseaes.2010.11.009

Cited by 35 publications

(25 citation statements)

References 84 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…But this peak-T stage could not last over a long time; otherwise, the garnet compositional zonation would have been obliterated. This is also supported by the well-preserved prograde chemical zoning in garnet of the South Dulan HP granulites (Yu et al 2011).…”

Section: Discussionmentioning

confidence: 57%

“…Zircon U-Pb dating obtained 832-838 Ma protolith ages for the continental-type eclogites and an identical 427-451 Ma metamorphic age for the continental-type eclogites and their country ortho-and paragneisses (Zhang et al , 2015Yu et al 2013a). The HP granulites along the western margin of South Dulan unit experienced HP granulite-facies metamorphism at 800-950°C, 14.5-18.5 kbar, during 433-438 Ma (Yu et al 2011(Yu et al , 2014.…”

Section: Subuduction Of Quartzofeldspathic Basement Of Qaidam Blockmentioning

confidence: 92%

“…Petrographic and geochronologic studies show that these HP granulites underwent HP granulite-facies metamorphism at 800-950°C, 14.5-18.5 kbar (Yu et al 2011), during 433-438 Ma (Yu et al 2014).…”

Section: Geological Settingmentioning

confidence: 99%

“…They are unconformably overlain by lower Palaeozoic arc-related volcanic and sedimentary rocks of Tanjianshan Group and Devonian molasses, and are intruded by granites (Figure 1b). Based on rock associations, petrological criteria, and field relationships, four UHP metamorphic units were recognized from west to east: (1) the Yuka eclogite-gneiss unit, consisting of coesite-bearing eclogite (Zhang et al 2009a), metapelite, granitic gneiss, and marble; (2) the Lüliangshan garnet peridotite-gneiss unit, which consists of diamond-bearing garnet peridotite (Song et al 2005b), eclogite (Chen et al 2013), kyanite-bearing paragneiss, and granitic gneiss; (3) the Xitieshan eclogitegneiss unit, including coesite-bearing eclogite , amphibolite, kyanite-bearing paragneiss , granitic gneiss, and rare marble; and (4) the Dulan eclogite-gneiss unit, comprising coesite-bearing eclogite (Song et al 2003a;Zhang et al 2009bZhang et al , 2010 and pelitic gneiss , HP granulite (Yu et al 2011(Yu et al , 2012(Yu et al , 2014, granitic gneiss (Song et al 2012;Yu et al 2013a), peridotite, and garnet pyroxenite ( Figure 1b).…”

Section: Geological Settingmentioning

confidence: 99%

“…Some HP granulites crop out along the western margin of the SDB (Figure 2a, Yu et al 2011Yu et al , 2014. Petrographic and geochronologic studies show that these HP granulites underwent HP granulite-facies metamorphism at 800-950°C, 14.5-18.5 kbar (Yu et al 2011), during 433-438 Ma (Yu et al 2014).…”

Section: Geological Settingmentioning

confidence: 99%

See 4 more Smart Citations

Petrology and geochronology of ultrahigh-pressure granitic gneiss from South Dulan, North Qaidam belt, NW China

Ren

Chen

Hauzenberger

et al. 2015

International Geology Review

View full text Add to dashboard Cite

An integrated study including petrography, mineral chemistry, metamorphic P-T path modelling, and zircon U-Pb dating was conducted on a granitic gneiss and enclosed eclogite from South Dulan, North Qaidam UHP (ultrahigh-pressure) belt. The result shows that the granitic gneiss underwent a clockwise P-T path with a peak-P stage at 655-745°C, 30-34 kbar, and a subsequent peak-T stage at 815-870°C, 14-18 kbar, which is similar to the P-T estimates reported for coesitebearing continental-type eclogites in this region. The enclosed eclogite resembles an olivinepyroxene-rich cumulate in Qaidam block. It has a similar prograde P-T path with the country gneiss and experienced a peak-P stage of 682-748°C at 27-34 kbar. Zircon U-Pb dating yields an eclogitefacies metamorphic age of 447 ± 2 Ma for the granitic gneiss and 445 ± 6 Ma for the enclosed eclogite. These ages agree with metamorphic ages obtained from paragneisses (427-439 Ma), coesite-bearing continental-type eclogites (430-451 Ma), and UHPM (ultrahigh-pressure metamorphic) oceanic crust-mantle sequence (440-445 Ma) from South Dulan, as well as UHP eclogites, garnet peridotite, and gneisses from other units (460-420 Ma) within this belt reported by others. Similar metamorphic ages as well as P-T evolution documented in gneisses and intercalated eclogites imply that both rocks experienced a coeval UHP event. Summarizing all the published geochronology data, we argue that the North Qaidam UHP belt was mainly formed by continental deep subduction at 460 to~420 Ma. The UHPM oceanic crust-mantle sequence in South Dulan may represent oceanic lithosphere in the transition zone between oceanic and continental crust, which was dragged upward by the exhumed continental rocks after break-off of the dense oceanic crust. ARTICLE HISTORY

show abstract

Section: Discussionmentioning

confidence: 57%

Section: Subuduction Of Quartzofeldspathic Basement Of Qaidam Blockmentioning

confidence: 92%

Section: Geological Settingmentioning

confidence: 99%

Section: Geological Settingmentioning

confidence: 99%

Section: Geological Settingmentioning

confidence: 99%

See 3 more Smart Citations

Petrology and geochronology of ultrahigh-pressure granitic gneiss from South Dulan, North Qaidam belt, NW China

Ren

Chen

Hauzenberger

et al. 2015

International Geology Review

View full text Add to dashboard Cite

show abstract

Early Paleozoic Tarim Orocline: Insights from paleogeography and tectonic evolution in the Tarim Basin

Wang

Zhao

et al. 2017

Geological Journal

View full text Add to dashboard Cite

The Tarim Basin, situated between the Paleo‐Asian tectonic domain and the Proto‐Tethys tectonic domain, has undergone a complex tectonic evolutionary process under various geodynamic conditions and has provided abundant information about the dynamic evolution of the peripheral orogens. From the Sinian to Early Ordovician, the Tarim–Qaidam Block was under a regional extensional setting. A carbonate platform developed widely in the basin, flanked by a passive continental margin setting. As the extension enhanced, the spreading of the Proto‐Tethys Ocean was accompanied by subduction and collision, which resulted in a nearly linear subduction zone. Since the Late Cambrian, a continuous oblique subduction and induced sinistral shearing produced an initial bending of the Proto‐Tethys subduction zone, leading to rotation and bend of the original Tarim–Qaidam Block and internal long striped subaqueous paleo‐uplift. During the Middle and Late Ordovician, the Altyn–Qilian Orogen underwent continent–continent collision and continental crust deep subduction. The buckling of the subduction system enhanced under the sinistral transpressional field, resulted in the bending of the Altyn–Qilian Orogen to an S‐shape. The subaqueous uplift areas in the basin were further elevated, rotated, and eroded to show an S‐shape distribution and an unconformity developed between the Silurian sediments and underlying strata. The extent of the carbonate platform decreased, around which developed a high‐energy facies in a platform margin and formed important oil–gas reservoirs. In the Silurian to Middle Devonian, the Tarim Basin evolved into a “two uplifts with a depression” framework under the dual‐directional compressional field. Near the end of the Late Devonian, the S‐shape distribution pattern of paleo‐uplifts was covered by the Upper Devonian and Carboniferous sequence in an angular unconformity. Moreover, the planar distribution of thrust faults with strike‐slip property around the paleo‐uplifts also showed an S‐shape. Accompanying small‐scale strike‐slip faults presented as the radial axial cleavages of plunging vertical folds around a vertical hinge, which indicated that the pre‐existing thrust faults bent around a vertical axis resulting from late strike‐slip faults, demonstrating a coupling between the Tarim Basin and orocline of the Early Paleozoic orogens in the Proto‐Tethys Ocean, called the Tarim Orocline.

show abstract

Early Paleozoic arc magmatism and metamorphism in the northern Qilian Block, western China: Petrological and geochronological constraints

Peng

Zhang

et al. 2017

Geological Journal

View full text Add to dashboard Cite

The Datong–Menyuan Complex, located in the northern margin of the Qilian Block, is composed dominantly of high‐grade metamorphic rocks covered by a Paleozoic–Mesozoic sedimentary sequence. In this study, we present petrographic observation, conventional thermobarometry and P–T pseudosection modelling, whole‐rock major and trace geochemistry, zircons U–Pb dating and Hf isotopic data together, to reveal the relationship between the magmatism and metamorphism along the northern margin of the Qilian Block. The anticlockwise P–T paths of gneiss and amphibolites are obtained using the garnet isopleths thermobaromety combined with phase equilibria modelling. The P–T pseudosection also shows that the gneiss and amphibolite underwent similar retrograde metamorphism with slightly different peak metamorphic conditions at ~720 °C and ~6.4 kbar for the former and ~700 °C and ~7.1 kbar for the latter. This indicates the Datong–Menyuan Complex recorded an amphibolite–granulite‐facies metamorphism. The zircon U–Pb analyses of 3 intrusive rocks including granitic dike, diorite, and granite are dated at ca. 499.8 ± 4.3, 495.9 ± 3.3, and 505.5 ± 3.2 Ma, and 3 representative metamorphic rocks underwent contemporaneous metamorphism at ca. 498.9 ± 4.1, 504.4 ± 3.9, and 499.3 ± 2.9 Ma. Zircon Hf isotopic analyses show that 505‐Ma zircons from the granitoid have positive εHf(t) values ranging from +8.5 to +12.8, indicating a depleted mantle source. Based on the penecontemporaneous magmatic and metamorphic event, we suggest that the southward subduction of the north Qilian Ocean triggered the activity of mantle‐derived magma and coeval metamorphic event. A subsequent compression is attributed to crustal thickening, indicating counter clockwise P–T paths. Combining these data with previous studies, it suggests paired metamorphic belts: the penecontemporaneous high‐temperature metamorphic belt related to an arc along the northern Qilian Block and high‐pressure/low‐temperature metamorphic belt existed in the north Qilian suture.

show abstract

Petrology and P–T path of high-pressure granulite from the Dulan area, North Qaidam Mountains, northwestern China

Cited by 35 publications

References 84 publications

Petrology and geochronology of ultrahigh-pressure granitic gneiss from South Dulan, North Qaidam belt, NW China

Petrology and geochronology of ultrahigh-pressure granitic gneiss from South Dulan, North Qaidam belt, NW China

Early Paleozoic Tarim Orocline: Insights from paleogeography and tectonic evolution in the Tarim Basin

Early Paleozoic arc magmatism and metamorphism in the northern Qilian Block, western China: Petrological and geochronological constraints

Contact Info

Product

Resources

About