FRINK Linked Data Fragments server

Matches in SemOpenAlex for { <https://semopenalex.org/work/W2013579065> ?p ?o ?g. }

• W2013579065 endingPage "161" @default.
• W2013579065 startingPage "105" @default.
• W2013579065 abstract "Discovery of coesite, diamond, and extreme 18O-depletion in eclogites from the Dabie–Sulu orogen in central-east China has contributed much to our understanding of subduction of continental crust to mantle depths and its subsequent exhumation. Hydrogen, oxygen, and carbon isotope distributions were systematically investigated in the past 8 years for ultrahigh pressure (UHP) eclogites, gneisses, granulites, marbles, and peridotites from this exciting region. The available data show the following characteristic features: (1) variable δ18O values of −11‰ to +10‰ for the eclogites and gneisses, with both equilibrium and disequilibrium fractionations of oxygen isotopes among minerals; (2) disequilibrium fractionation of hydrogen isotopes between mica and epidote from both eclogites and gneisses, with low δD values up to −127‰ to −100‰ for phengite; (3) negative δ13C values of −28‰ to −21‰ for apatite as well as host-eclogites and gneisses; (4) positive δ13C values of +1‰ to +6‰ for coesite-bearing marble associated with eclogites; (5) zircons from metamorphic rocks of different grades show a large variation in δ18O from −11‰ to +9‰, with U–Pb ages of 700 to 800 Ma for the timing of low-δ18O magma crystallization. It appears that the UHP metamorphic rocks exhibit ranges of δ18O values that are typical of potential precursor protolith rocks. Preservation of the oxygen isotope equilibrium fractionations among the minerals of the UHP eclogites and gneisses suggests that these rocks acquired the low δ18O values by meteoric-hydrothermal alteration before the UHP metamorphism. Thus, the UHP metamorphic rocks largely reflect the δ18O values of their premetamorphic igneous or sedimentary precursors. The stable isotope data demonstrate that basaltic, granitic, and sedimentary protoliths of the eclogites, orthogneiss, and paragneiss in the orogen were at or near the earth's surface, and subjected to varying degrees of water–rock interaction at some time before plate subduction. The low-δ18O rocks were isolated from water–rock interactions during their descent to and return from mantle depths. It appears that the oxygen, hydrogen, and carbon on the earth's surface were recycled into the mantle at depths of >200 km by the continental subduction. A fried ice cream model is advanced as an analogy to the rapid processes of both plate subduction and exhumation, with a short residence time of the UHP slab at mantle depths. The entire cycle of subduction, UHP metamorphism, and exhumation is estimated to take place in about 10 to 20 Ma. The 18O-depleted zircons and other minerals acquired their oxygen isotope compositions from low-δ18O magmas that incorporated the isotopic signatures of meteoric water in rifting tectonic zones prior to solidification. The U–Pb discordia dating for the 18O-depleted zircons revealed that the meteoric water–rock interaction occurred at Neoproterozoic, a time being much earlier than the UHP metamorphism at Triassic, but correlated with the Rodinian breakup, positive carbon isotope anomaly in carbonates, and the snowball earth event. The unusually low δ18O values can be acquired from either the meteoric water of cold paleoclimates or the melt water of glacial ice or snow. Neoproterozoic rift magmatism along the northern margin of the Yangtze craton may have provided sufficient heat source to trigger the meteoric-hydrothermal circulation. It is possible that the unusual 18O-depletion in the meta-igneous rocks occurs at some time prior to the snowball earth event, when there is a transition from a very cold earth with continental glaciers to a widely glaciated earth where bulk of the earth is covered by sea ice as defined for the snowball earth. The heterogeneity of oxygen isotope compositions at outcrop scales demonstrates the absence of pervasive fluid infiltration during prograde, peak UHP, and retrograde metamorphism; most rocks appear to have recrystallized under virtually closed system conditions characterized by widespread lack of an aqueous fluid phase. Volatiles may not escape from the rock series during the rapid subduction of the continental crust, resulting in a general lack of syn-collisional arc-magmatism in this orogen. Big differences in pressure and time from the peak UHP stage to the retrograde HP eclogite-facies stage cause significant release of aqueous fluid by dehydration from decompressing slabs during exhumation. As a result, fluid flow occurred in a channellized way on small scales subsequent to the UHP metamorphism, with very limited mobility of fluid at peak UHP conditions. The fluid for retrograde reactions was internally buffered in stable isotope compositions. While some fluids were locally derived from the surrounding gneisses, more fluid was probably derived from internal dehydration of the rock units in question. In addition to the breakdown of hydroxyl-bearing minerals, exsolution of structural hydroxyl dissolved in nominally anhydrous minerals due to abrupt decrease in pressure may have been an important source for the retrograde fluid." @default.
• W2013579065 created "2016-06-24" @default.
• W2013579065 creator A5038855167 @default.
• W2013579065 creator A5053849442 @default.
• W2013579065 creator A5056465234 @default.
• W2013579065 creator A5090514819 @default.
• W2013579065 date "2003-07-01" @default.
• W2013579065 modified "2023-10-18" @default.
• W2013579065 title "Stable isotope geochemistry of ultrahigh pressure metamorphic rocks from the Dabie–Sulu orogen in China: implications for geodynamics and fluid regime" @default.
• W2013579065 cites W1517332489 @default.
• W2013579065 cites W1523733318 @default.
• W2013579065 cites W1556773719 @default.
• W2013579065 cites W1575749970 @default.
• W2013579065 cites W1615737483 @default.
• W2013579065 cites W1645613791 @default.
• W2013579065 cites W1703316128 @default.
• W2013579065 cites W1846400597 @default.
• W2013579065 cites W1885343710 @default.
• W2013579065 cites W1964408118 @default.
• W2013579065 cites W1964417915 @default.
• W2013579065 cites W1965758707 @default.
• W2013579065 cites W1966039270 @default.
• W2013579065 cites W1966610015 @default.
• W2013579065 cites W1967021970 @default.
• W2013579065 cites W1967700183 @default.
• W2013579065 cites W1968264141 @default.
• W2013579065 cites W1968306266 @default.
• W2013579065 cites W1968392251 @default.
• W2013579065 cites W1968541811 @default.
• W2013579065 cites W1969959072 @default.
• W2013579065 cites W1971697013 @default.
• W2013579065 cites W1972673996 @default.
• W2013579065 cites W1972715171 @default.
• W2013579065 cites W1973345512 @default.
• W2013579065 cites W1973432121 @default.
• W2013579065 cites W1974258910 @default.
• W2013579065 cites W1974454715 @default.
• W2013579065 cites W1974575744 @default.
• W2013579065 cites W1975210824 @default.
• W2013579065 cites W1975652198 @default.
• W2013579065 cites W1978455874 @default.
• W2013579065 cites W1979092798 @default.
• W2013579065 cites W1979476030 @default.
• W2013579065 cites W1979601121 @default.
• W2013579065 cites W1980041031 @default.
• W2013579065 cites W1980313149 @default.
• W2013579065 cites W1980419960 @default.
• W2013579065 cites W1981238025 @default.
• W2013579065 cites W1981344517 @default.
• W2013579065 cites W1981544426 @default.
• W2013579065 cites W1982294268 @default.
• W2013579065 cites W1983041159 @default.
• W2013579065 cites W1983948966 @default.
• W2013579065 cites W1984724289 @default.
• W2013579065 cites W1984811175 @default.
• W2013579065 cites W1984990132 @default.
• W2013579065 cites W1984991651 @default.
• W2013579065 cites W1985195619 @default.
• W2013579065 cites W1985297387 @default.
• W2013579065 cites W1985430089 @default.
• W2013579065 cites W1988503846 @default.
• W2013579065 cites W1989288212 @default.
• W2013579065 cites W1990060235 @default.
• W2013579065 cites W1990581568 @default.
• W2013579065 cites W1990751086 @default.
• W2013579065 cites W1992017229 @default.
• W2013579065 cites W1993638742 @default.
• W2013579065 cites W1993780763 @default.
• W2013579065 cites W1994209198 @default.
• W2013579065 cites W1994590968 @default.
• W2013579065 cites W1994827132 @default.
• W2013579065 cites W1994847567 @default.
• W2013579065 cites W1996340995 @default.
• W2013579065 cites W1996361224 @default.
• W2013579065 cites W1996380317 @default.
• W2013579065 cites W1996760337 @default.
• W2013579065 cites W1997092735 @default.
• W2013579065 cites W1997580863 @default.
• W2013579065 cites W1997700587 @default.
• W2013579065 cites W1998481085 @default.
• W2013579065 cites W1998611435 @default.
• W2013579065 cites W1999408569 @default.
• W2013579065 cites W1999621813 @default.
• W2013579065 cites W2000563553 @default.
• W2013579065 cites W2003809053 @default.
• W2013579065 cites W2004471465 @default.
• W2013579065 cites W2004874510 @default.
• W2013579065 cites W2006007992 @default.
• W2013579065 cites W2006389174 @default.
• W2013579065 cites W2006471814 @default.
• W2013579065 cites W2006880125 @default.
• W2013579065 cites W2007113204 @default.
• W2013579065 cites W2007766082 @default.
• W2013579065 cites W2008548916 @default.
• W2013579065 cites W2009029744 @default.
• W2013579065 cites W2011049153 @default.
• W2013579065 cites W2011304272 @default.
• W2013579065 cites W2013266432 @default.

• next