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Rapid and precise determination of natural carbonate rare earth elements in femtogram quantities by ICP-SF-MS (Chung-Che Wu and others) A rapid and precise technique for measuring of femtogram quantity rare earth elements (REE) levels in natural carbonate samples by ICP-SF-MS, has been developed, at the Department of Geosciences, National Taiwan University. REE/Ca ratios are calculated directly from the intensities of the ion beams of 46Ca, 139La, 140Ce, 141Pr, 146Nd, 147Sm, 153Eu, 160Gd, 159Tb, 163Dy, 165Ho, 166Er, 169Tm, 172Yb, and 175Lu using external matrix-matched synthetic standards to correct for instrumental ratio drifting and mass discrimination. A routine measurement time of 3 minutes is typical for one sample containing 20-40-ppm [Ca]. Replicate measurements made on natural coral and foraminiferal samples with REE/Ca ratios of 2-242 nmol/mol show external precisions of 1.9-6.5% (2RSD) can be achieved with only 10-1000 femtogram REEs in 10-20 μg carbonate consumed. The key advantages of this established technique are to (1) provide a possibility of directly analyzing REE isotopic composition in femtogram quantities without chemical separation steps (2) and to offer high precision, high temporal resolution REE records in carbonates, such as sclerosponges, tufa, and speleothems.
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Rapid and precise determination of natural carbonate rare earth elements in femtogram quantities by ICP-SF-MS (Chung-Che Wu and others) Rapid and precise determination of rare earth elements in femtogram quantity in natural carbonate by ICP-SF-MS A rapid and precise technique for measuring of femtogram quantity rare earth elements (REE) levels in natural carbonate samples by ICP-SF-MS, has been developed, at the Department of Geosciences, National Taiwan University. A rapid and precise technique for measuring femtograms of rare earth elements (REE) in natural carbonate samples at the Department of.... REE/Ca ratios are calculated directly from the intensities of the ion beams of 46Ca, 139La, 140Ce, 141Pr, 146Nd, 147Sm, 153Eu, 160Gd, 159Tb, 163Dy, 165Ho, 166Er, 169Tm, 172Yb, and 175Lu using external matrix-matched synthetic standards to correct for instrumental ratio drifting and mass discrimination. REE/Ca ratios are calculated directly from the intensities of the ion beams of 46Ca, 139La, 140Ce, 141Pr, 146Nd, 147Sm, 153Eu, 160Gd, 159Tb, 163Dy, 165Ho, 166Er, 169Tm, 172Yb, and 175Lu. External matrix-matched synthetic standards were to correct the instrumental ratio drifting and mass discrimination.
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A routine measurement time of 3 minutes is typical for one sample containing 20- 40-ppm [Ca]. Replicate measurements made on natural coral and foraminiferal samples with REE/Ca ratios of 2-242 nmol/mol show external precisions of 1.9- 6.5% (2RSD) can be achieved with only 10-1000 femtogram REEs in 10-20 μg carbonate consumed. A measurement time of 3 minutes is routine (or typical) for one sample containing 20-40-ppm of Ca. Replicate analyses on natural coral and foraminiferal samples with REE/Ca ratios of 2-242 nmol/mol show that an external precision of 1.9-6.5% (2RSD) can be achieved, with only 10-1000 femtograms of REEs in 10-20 μg carbonate consumed. The key advantages of this established technique are to (1) provide a possibility of directly analyzing REE isotopic composition in femtogram quantities without chemical separation steps (2) and to offer high precision, high temporal resolution REE records in carbonates, such as sclerosponges, tufa, and speleothems. The key advantages of this technique are (1) to provide a possibility of direct measurement of REE isotopic composition in femtogram quantity without chemical separation, and (2) to offer a high precision and high temporal resolution of REE records in carbonates, such as sclerosponges, tufa and speleothems. (The precise meaning of “10-1000 femtograms of REEs”, “analyzing REE isotopic composition” is not clear)
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Toward a seismic tomography of Taiwan orogeny from joint inversion of local and teleseismic data (Huang, Hsin-Hua and others) Taiwan orogenic belt is created by the oblique collision between the Eurasian continental margin and Luzon volcanic arc riding on the Philippine Sea Plate. It is one of the youngest and most active orogenies in the world, accompanied by numerous faults and high seismicity. Many previous studies have been conducted and provided abundant measurements and observations in various fields, including geophysics, geodesy, geology, geomorphology, and so on. However, the mechanism of mountain building is still being under debate (e.g., Suppe, 1980, 1981; Wu et al., 1997; Shyu et al., 2005a). Among the proposed models, a key controversy is the different interpretations of deeper structures such as South China Sea Plate, Fore-arc basement, and the geometry of subducting slabs. Seismic tomography is one of the important techniques to uncover the subsurface structures. Yet numerous local seismic tomographic studies that have been carried out since 1990s (Rau and Wu, 1995; Ma et al., 1996; Kim et al., 2005; Wu et al., 2007) have been limited by the irregular distribution of local seismicity. The resolution of most of them can only reach to 40-50 km except the subduction zones because of no earthquakes occurring deeper. Therefore, integrating additional data, e.g. teleseismic data, to extend the resolution to the deeper part is truly needed. In this study, we jointly invert the local and teleseismic data simultaneously to gain the insight into the upper mantle. By exposing the deeper structures, we are enabled to inspect the different models of Taiwan orogeny.
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Toward a seismic tomography of Taiwan orogeny from joint inversion of local and teleseismic data (Huang, Hsin-Hua and others) Seismic tomography of the Taiwan orogeny derived from a joint inversion of local and teleseismic data Taiwan orogenic belt is created by the oblique collision between the Eurasian continental margin and Luzon volcanic arc riding on the Philippine Sea Plate. The Taiwan orogenic belt was created by (the) oblique collision between the Eurasian continental margin and the Luzon volcanic arc riding on the Philippine Sea Plate. It is one of the youngest and most active orogenies in the world, accompanied by numerous faults and high seismicity. Many previous studies have been conducted and provided abundant measurements and observations in various fields, including geophysics, geodesy, geology, geomorphology, and so on. However, the mechanism of mountain building is still being under debate (e.g., Suppe, 1980, 1981; Wu et al., 1997; Shyu et al., 2005a). It is one of the youngest and most active orogens in the world, characterizied by numerous active faults and high seismicity. The orogenic development has been studied by a variety of techniques, including geophysics, geodesy, geology, geomorphology, and geochemistry. However, the mechanism of mountain building is still much debated.
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Among the proposed models, a key controversy is the different interpretations of deeper structures such as South China Sea Plate, Fore-arc basement, and the geometry of subducting slabs. Seismic tomography is one of the important techniques to uncover the subsurface structures. Yet numerous local seismic tomographic studies that have been carried out since 1990s (Rau and Wu, 1995; Ma et al., 1996; Kim et al., 2005; Wu et al., 2007) have been limited by the irregular distribution of local seismicity. The resolution of most of them can only reach to 40-50 km except the subduction zones because of no earthquakes occurring deeper. The key controversy is about the interpretation of deeper structures, such as the South China Sea Plate, the fore-arc basement, and the geometry of subducting slabs. Seismic tomography is one of the best techniques used to delineate the subsurface structures. However, many local seismic tomographic studies since 1990s (Rau and Wu, 1995; Ma et al., 1996; Kim et al., 2005; Wu et al., 2007) have been limited by the irregular distribution of seismicity. The resolution of most studies (?) only reaches 40-50 km, except the subduction zones, because no earthquakes occur deeper. (due to the absence of deeper earthquakes)
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Therefore, integrating additional data, e.g. teleseismic data, to extend the resolution to the deeper part is truly needed. In this study, we jointly invert the local and teleseismic data simultaneously to gain the insight into the upper mantle. By exposing the deeper structures, we are enabled to inspect the different models of Taiwan orogeny. In this study, we performed a joint inversion of the local and teleseismic data to gain the insight into the upper mantle. The revealed deeper structures enable us to examine and verify the different models of the Taiwan orogenic processes.
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