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Urs Schaltegger - One of the best experts on this subject based on the ideXlab platform.
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the mafic Ultramafic Rock association of loderio biasca lower pennine nappes ticino switzerland cambrian oceanic magmatism and its bearing on early paleozoic paleogeography
Chemical Geology, 2002Co-Authors: Urs Schaltegger, Dieter Gebauer, Albrecht Von QuadtAbstract:Abstract Dismembered relics of mafic and Ultramafic Rock in high-grade basement Rocks often record pre-collisional stages of deep lithospheric and/or oceanic mafic magmatism in an orogen. A lens of amphibolites and serpentinites, intercalated between the crystalline Simano and Leventina nappes (lower Penninic nappes, Central Alps, Switzerland) was investigated for the protolith age and chemical and isotopic composition. Despite the polyphase high-grade metamorphic overprinting, primary isotopic and chemical relationships are still preserved and are indicative of an origin in an active margin situation. Trace element geochemistry and Nd isotopes of amphibolites argue for the fractionated gabbros as protoliths, which were formed by the partial melting of the upper mantle. The Rocks show a variation of e Nd values from +7.3 to +4.2 and Nd model ages up to 2 Ga, taken as evidence for the contamination by a geochemically enriched, old lithospheric source. Sr isotopes are heavily disturbed through the percolating crustal fluids after the emplacement into the continental crust. U–Pb age determination of zircon from two amphibolites using both in situ (SHRIMP) and conventional methods converge at an age of 518±11 Ma for the crystallization of the protoliths. The Rock association of Loderio–Biasca is a further example from the Alpine basement recording an oceanic domain between Gondwana and the different Gondwana-derived microcontinents in the Cambrian–Ordovician times. Remnants of this ocean were incorporated into the accretionary wedges that formed during the subduction/collision events from Ordovician to Carboniferous, commonly summarized as the Caledonian and Variscan orogeny, and are today spread over the so-called Saxothurigian and Moldanubian domain of the Variscan orogen. These domains consist, thus to large extents, of heterochronous accretionary wedge sequences.
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The mafic–Ultramafic Rock association of Loderio–Biasca (lower Pennine nappes, Ticino, Switzerland): Cambrian oceanic magmatism and its bearing on early Paleozoic paleogeography
Chemical Geology, 2002Co-Authors: Urs Schaltegger, Dieter Gebauer, Albrecht Von QuadtAbstract:Dismembered relics of mafic and Ultramafic Rock in high-grade basement Rocks often record pre-collisional stages of deep lithospheric and/or oceanic mafic magmatism in an orogen. A lens of amphibolites and serpentinites, intercalated between the crystalline Simano and Leventina nappes (lower Penninic nappes, Central Alps, Switzerland) was investigated for the protolith age and chemical and isotopic composition. Despite the polyphase high-grade metamorphic overprinting, primary isotopic and chemical relationships are still preserved and are indicative of an origin in an active margin situation. Trace element geochemistry and Nd isotopes of amphibolites argue for the fractionated gabbros as protoliths, which were formed by the partial melting of the upper mantle. The Rocks show a variation of eNd values from + 7.3 to + 4.2 and Nd model ages up to 2 Ga, taken as evidence for the contamination by a geochemically enriched, old lithospheric source. Sr isotopes are heavily disturbed through the percolating crustal fluids after the emplacement into the continental crust. U-Pb age determination of zircon from two amphibolites using both in situ (SHRIMP) and conventional methods converge at an age of 518F11 Ma for the crystallization of the protoliths. The Rock association of Loderio-Biasca is a further example from the Alpine basement recording an oceanic domain between Gondwana and the different Gondwana-derived microcontinents in the Cambrian- Ordovician times. Remnants of this ocean were incorporated into the accretionary wedges that formed during the subduction/ collision events from Ordovician to Carboniferous, commonly summarized as the Caledonian and Variscan orogeny, and are today spread over the so-called Saxothurigian and Moldanubian domain of the Variscan orogen. These domains consist, thus to large extents, of heterochronous accretionary wedge sequence
Albrecht Von Quadt - One of the best experts on this subject based on the ideXlab platform.
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The mafic–Ultramafic Rock association of Loderio–Biasca (lower Pennine nappes, Ticino, Switzerland): Cambrian oceanic magmatism and its bearing on early Paleozoic paleogeography
Chemical Geology, 2002Co-Authors: Urs Schaltegger, Dieter Gebauer, Albrecht Von QuadtAbstract:Dismembered relics of mafic and Ultramafic Rock in high-grade basement Rocks often record pre-collisional stages of deep lithospheric and/or oceanic mafic magmatism in an orogen. A lens of amphibolites and serpentinites, intercalated between the crystalline Simano and Leventina nappes (lower Penninic nappes, Central Alps, Switzerland) was investigated for the protolith age and chemical and isotopic composition. Despite the polyphase high-grade metamorphic overprinting, primary isotopic and chemical relationships are still preserved and are indicative of an origin in an active margin situation. Trace element geochemistry and Nd isotopes of amphibolites argue for the fractionated gabbros as protoliths, which were formed by the partial melting of the upper mantle. The Rocks show a variation of eNd values from + 7.3 to + 4.2 and Nd model ages up to 2 Ga, taken as evidence for the contamination by a geochemically enriched, old lithospheric source. Sr isotopes are heavily disturbed through the percolating crustal fluids after the emplacement into the continental crust. U-Pb age determination of zircon from two amphibolites using both in situ (SHRIMP) and conventional methods converge at an age of 518F11 Ma for the crystallization of the protoliths. The Rock association of Loderio-Biasca is a further example from the Alpine basement recording an oceanic domain between Gondwana and the different Gondwana-derived microcontinents in the Cambrian- Ordovician times. Remnants of this ocean were incorporated into the accretionary wedges that formed during the subduction/ collision events from Ordovician to Carboniferous, commonly summarized as the Caledonian and Variscan orogeny, and are today spread over the so-called Saxothurigian and Moldanubian domain of the Variscan orogen. These domains consist, thus to large extents, of heterochronous accretionary wedge sequence
Albrecht Von Quadt - One of the best experts on this subject based on the ideXlab platform.
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the mafic Ultramafic Rock association of loderio biasca lower pennine nappes ticino switzerland cambrian oceanic magmatism and its bearing on early paleozoic paleogeography
Chemical Geology, 2002Co-Authors: Urs Schaltegger, Dieter Gebauer, Albrecht Von QuadtAbstract:Abstract Dismembered relics of mafic and Ultramafic Rock in high-grade basement Rocks often record pre-collisional stages of deep lithospheric and/or oceanic mafic magmatism in an orogen. A lens of amphibolites and serpentinites, intercalated between the crystalline Simano and Leventina nappes (lower Penninic nappes, Central Alps, Switzerland) was investigated for the protolith age and chemical and isotopic composition. Despite the polyphase high-grade metamorphic overprinting, primary isotopic and chemical relationships are still preserved and are indicative of an origin in an active margin situation. Trace element geochemistry and Nd isotopes of amphibolites argue for the fractionated gabbros as protoliths, which were formed by the partial melting of the upper mantle. The Rocks show a variation of e Nd values from +7.3 to +4.2 and Nd model ages up to 2 Ga, taken as evidence for the contamination by a geochemically enriched, old lithospheric source. Sr isotopes are heavily disturbed through the percolating crustal fluids after the emplacement into the continental crust. U–Pb age determination of zircon from two amphibolites using both in situ (SHRIMP) and conventional methods converge at an age of 518±11 Ma for the crystallization of the protoliths. The Rock association of Loderio–Biasca is a further example from the Alpine basement recording an oceanic domain between Gondwana and the different Gondwana-derived microcontinents in the Cambrian–Ordovician times. Remnants of this ocean were incorporated into the accretionary wedges that formed during the subduction/collision events from Ordovician to Carboniferous, commonly summarized as the Caledonian and Variscan orogeny, and are today spread over the so-called Saxothurigian and Moldanubian domain of the Variscan orogen. These domains consist, thus to large extents, of heterochronous accretionary wedge sequences.
Dieter Gebauer - One of the best experts on this subject based on the ideXlab platform.
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the mafic Ultramafic Rock association of loderio biasca lower pennine nappes ticino switzerland cambrian oceanic magmatism and its bearing on early paleozoic paleogeography
Chemical Geology, 2002Co-Authors: Urs Schaltegger, Dieter Gebauer, Albrecht Von QuadtAbstract:Abstract Dismembered relics of mafic and Ultramafic Rock in high-grade basement Rocks often record pre-collisional stages of deep lithospheric and/or oceanic mafic magmatism in an orogen. A lens of amphibolites and serpentinites, intercalated between the crystalline Simano and Leventina nappes (lower Penninic nappes, Central Alps, Switzerland) was investigated for the protolith age and chemical and isotopic composition. Despite the polyphase high-grade metamorphic overprinting, primary isotopic and chemical relationships are still preserved and are indicative of an origin in an active margin situation. Trace element geochemistry and Nd isotopes of amphibolites argue for the fractionated gabbros as protoliths, which were formed by the partial melting of the upper mantle. The Rocks show a variation of e Nd values from +7.3 to +4.2 and Nd model ages up to 2 Ga, taken as evidence for the contamination by a geochemically enriched, old lithospheric source. Sr isotopes are heavily disturbed through the percolating crustal fluids after the emplacement into the continental crust. U–Pb age determination of zircon from two amphibolites using both in situ (SHRIMP) and conventional methods converge at an age of 518±11 Ma for the crystallization of the protoliths. The Rock association of Loderio–Biasca is a further example from the Alpine basement recording an oceanic domain between Gondwana and the different Gondwana-derived microcontinents in the Cambrian–Ordovician times. Remnants of this ocean were incorporated into the accretionary wedges that formed during the subduction/collision events from Ordovician to Carboniferous, commonly summarized as the Caledonian and Variscan orogeny, and are today spread over the so-called Saxothurigian and Moldanubian domain of the Variscan orogen. These domains consist, thus to large extents, of heterochronous accretionary wedge sequences.
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The mafic–Ultramafic Rock association of Loderio–Biasca (lower Pennine nappes, Ticino, Switzerland): Cambrian oceanic magmatism and its bearing on early Paleozoic paleogeography
Chemical Geology, 2002Co-Authors: Urs Schaltegger, Dieter Gebauer, Albrecht Von QuadtAbstract:Dismembered relics of mafic and Ultramafic Rock in high-grade basement Rocks often record pre-collisional stages of deep lithospheric and/or oceanic mafic magmatism in an orogen. A lens of amphibolites and serpentinites, intercalated between the crystalline Simano and Leventina nappes (lower Penninic nappes, Central Alps, Switzerland) was investigated for the protolith age and chemical and isotopic composition. Despite the polyphase high-grade metamorphic overprinting, primary isotopic and chemical relationships are still preserved and are indicative of an origin in an active margin situation. Trace element geochemistry and Nd isotopes of amphibolites argue for the fractionated gabbros as protoliths, which were formed by the partial melting of the upper mantle. The Rocks show a variation of eNd values from + 7.3 to + 4.2 and Nd model ages up to 2 Ga, taken as evidence for the contamination by a geochemically enriched, old lithospheric source. Sr isotopes are heavily disturbed through the percolating crustal fluids after the emplacement into the continental crust. U-Pb age determination of zircon from two amphibolites using both in situ (SHRIMP) and conventional methods converge at an age of 518F11 Ma for the crystallization of the protoliths. The Rock association of Loderio-Biasca is a further example from the Alpine basement recording an oceanic domain between Gondwana and the different Gondwana-derived microcontinents in the Cambrian- Ordovician times. Remnants of this ocean were incorporated into the accretionary wedges that formed during the subduction/ collision events from Ordovician to Carboniferous, commonly summarized as the Caledonian and Variscan orogeny, and are today spread over the so-called Saxothurigian and Moldanubian domain of the Variscan orogen. These domains consist, thus to large extents, of heterochronous accretionary wedge sequence
Chao Ding - One of the best experts on this subject based on the ideXlab platform.
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Developing a thermal characteristic index for lithology identification using thermal infrared remote sensing data
Advances in Space Research, 2017Co-Authors: Jiali Wei, Chao Ding, Xiangnan Liu, Meiling Liu, Ming JinAbstract:Abstract In remote sensing petrology fields, studies have mainly concentrated on spectroscopy remote sensing research, and methods to identify minerals and Rocks are mainly based on the analysis and enhancement of spectral features. Few studies have reported the application of thermodynamics for lithology identification. This paper aims to establish a thermal characteristic index ( TCI ) to explore Rock thermal behavior responding to defined environmental systems. The study area is located in the northern Qinghai Province, China, on the northern edge of the Qinghai-Tibet Plateau, where mafic-Ultramafic Rock, quartz-rich Rock, alkali granite Rock and carbonate Rock are well exposed; the pixel samples of these Rocks and vegetation were obtained based on relevant indices and geological maps. The scatter plots of TCI indicate that mafic-Ultramafic Rock and quartz-rich Rock can be well extracted from other surface objects when interference from vegetation is lower. On account of the complexity of environmental systems, three periods of TCI were used to construct a three-dimensional scatter plot, named the multi-temporal thermal feature space (MTTFS) model. Then, the Bayes discriminant analysis algorithm was applied to the MTTFS model to extract Rocks quantitatively. The classification accuracy of mafic-Ultramafic Rock is more than 75% in both training data and test data, which suggests TCI can act as a sensitive indicator to distinguish Rocks and the MTTFS model can accurately extract mafic-Ultramafic Rock from other surface objects. We deduce that the use of thermodynamics is promising in lithology identification when an effective index is constructed and an appropriated model is selected.
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Quartzose–mafic spectral feature space model: A methodology for extracting felsic Rocks with ASTER thermal infrared radiance data
Ore Geology Reviews, 2015Co-Authors: Chao Ding, Xiangnan Liu, Liting ZhaoAbstract:Abstract The original spectral features of felsic Rocks are often intermingled with other surface objects, which results in difficulty of detecting felsic Rocks using remote sensing techniques. Few felsic Rock indices were proposed and visual interpretation with RGB false color composition is widely used to detect felsic Rocks. This paper aims to construct a two-dimensional spectral feature space model to extract felsic Rocks using ASTER thermal infrared radiance data. The study area is located in northern Qinghai Province, western China with average altitude of approximately 4200 m. A large number of training pixels of mafic–Ultramafic Rock, quartz-rich Rock, felsic Rock, carbonate Rock and vegetation were selected from the ASTER images as samples of these surface objects. Then we used a quartz-rich Rock index (QI, QI = band14 − 0.844 × band12 − 1.897) and a mafic–Ultramafic Rock index (MI, MI = 0.915 × band10 − band13 + 1.437) to generate a two-dimensional scatter plot. The plot was named after quartzose–mafic spectral feature space (QMFS). The samples show an approximate triangular shape in the QMFS. Mafic–Ultramafic Rock, quartz-rich Rock and carbonate Rock are located in separate locations in the three vertex regions, respectively, while felsic Rock is located in the central region of the triangle. Next, we calculated a linear belt of silicate Rocks in which silicate Rocks vary regularly by using a linear regression analysis in the QMFS. Statistical characteristics of the felsic Rock samples are analyzed. Afterwards, a polygon which delineates the distribution of felsic Rock samples was constructed from the linear belt of silicate Rocks. Then we generated a system of inequalities based on the equations of the edges of the polygon. The application of the inequalities to the ASER images shows a good performance of the QMFS for extracting felsic Rocks.
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Mafic-Ultramafic and quartz-rich Rock indices deduced from ASTER thermal infrared data using a linear approximation to the Planck function
Ore Geology Reviews, 2014Co-Authors: Chao Ding, Xiangnan Liu, Wencan Liu, Meiling LiuAbstract:Abstract ASTER thermal infrared (TIR) data are widely used to detect mafic–Ultramafic Rock and quartz-rich Rock, and several Rock indices have been proposed based on emissivity features. However, ASTER TIR bands of radiance data correlate highly with each other, which indicates that the independent information derived from different bands may be limited, what's more, ASTER TIR radiance-at-sensor data contain atmospheric effect and temperature information, thus interfering with the availability of these previously proposed indices. In this study, we aim to explain the correlation using a linear approximation of the Planck function and deduce a linear equation that represents the relationship of the radiance between two TIR bands. Theoretical difference indices were deduced based on the linear equation and regression residual characteristics for any two ASTER TIR radiance bands. The study area is located in Qinghai Province, China, and belongs to the Qinghai–Tibet Plateau, where the average elevation is approximately 4200 m. A scatter plot of radiance derived from the ASTER image that overlaps the study area indicates that mafic–Ultramafic Rock and quartz-rich Rock can be distinguished from other surface objects well. Two mafic–Ultramafic Rock indices (MI1 = b13 − 0.9147 ∗ b10 − 1.4366 and MI2 = b13 − 0.8945 ∗ b11 − 1.2404) and two quartz-rich Rock indices (QI1 = b13 − 0.9261 ∗ b12 − 1.4623 and QI2 = b14 − 0.844 ∗ b12 − 1.8971) were proposed; they satisfactorily map these Rock units. The atmospheric effect on the indices is weak in arid or high-elevation region, so it will not interfere with the indices obviously in these regions. One-way variance analysis was performed to discuss the stability of the indices with respect to temperature. The mafic–Ultramafic Rock indices are found to be independent of temperature, whereas the values of quartz-rich Rock indices increase with the rising of temperature. We thus conclude that the quartz-rich Rock indices are suitable for the high-elevation region only, while the mafic–Ultramafic Rock indices may be capable of detecting these Rocks in regions with different natural conditions.
