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American Geophysical Union (AGU)

SCOPUS (2000-2023)SCIE-ISI

  1525-2027

  1525-2027

 

Cơ quản chủ quản:  AMER GEOPHYSICAL UNION , Wiley-Blackwell

Lĩnh vực:
GeophysicsGeochemistry and Petrology

Các bài báo tiêu biểu

An updated digital model of plate boundaries
Tập 4 Số 3 - 2003
Peter Bird
A global set of present plate boundaries on the Earth is presented in digital form. Most come from sources in the literature. A few boundaries are newly interpreted from topography, volcanism, and/or seismicity, taking into account relative plate velocities from magnetic anomalies, moment tensor solutions, and/or geodesy. In addition to the 14 large plates whose motion was described by the...... hiện toàn bộ
Relationships between the trace element composition of sedimentary rocks and upper continental crust
Tập 2 Số 4 - 2001
S. M. McLennan
Estimates of the average composition of various Precambrian shields and a variety of estimates of the average composition of upper continental crust show considerable disagreement for a number of trace elements, including Ti, Nb, Ta, Cs, Cr, Ni, V, and Co. For these elements and others that are carried predominantly in terrigenous sediment, rather than in solution (and ultimately into chem...... hiện toàn bộ
Age, spreading rates, and spreading asymmetry of the world's ocean crust
Tập 9 Số 4 - 2008
R. Dietmar Müller, Maria Seton, Carmen Gaina, W. R. Roest
We present four companion digital models of the age, age uncertainty, spreading rates, and spreading asymmetries of the world's ocean basins as geographic and Mercator grids with 2 arc min resolution. The grids include data from all the major ocean basins as well as detailed reconstructions of back‐arc basins. The age, spreading rate, and asymmetry at each grid node are determined by linea...... hiện toàn bộ
Global Multi‐Resolution Topography synthesis
Tập 10 Số 3 - 2009
William B. F. Ryan, S. M. Carbotte, J. Coplan, Suzanne O’Hara, A. K. Melkonian, R. A. Arko, R. Weissel, V. L. Ferrini, A. M. Goodwillie, F. O. Nitsche, J. Bonczkowski, Richard Zemsky
Seafloor bathymetric data acquired with modern swath echo sounders provide coverage for only a small fraction of the global seabed yet are of high value for studies of the dynamic processes of seafloor volcanism, tectonics, mass wasting, and sediment transport that create and shape the undersea landscape. A new method for compilation of global seafloor bathymetry that preserves the native ...... hiện toàn bộ
Composition of the depleted mantle
Tập 5 Số 5 - 2004
Vincent J. M. Salters, Andreas Stracke
We present an estimate for the composition of the depleted mantle (DM), the source for mid‐ocean ridge basalts (MORBs). A combination of approaches is required to estimate the major and trace element abundances in DM. Absolute concentrations of few elements can be estimated directly, and the bulk of the estimates is derived using elemental ratios. The isotopic composition of MORB allows ca...... hiện toàn bộ
The geodynamic equation of state: What and how
Tập 10 Số 10 - 2009
J. A. D. Connolly
Geodynamic models commonly assume equations of state as a function of pressure and temperature. This form is legitimate for homogenous materials, but it is impossible to formulate a general equation of state for a polyphase aggregate, e.g., a rock, as a function of pressure and temperature because these variables cannot distinguish all possible states of the aggregate. In consequence, the ...... hiện toàn bộ
A study of cleaning procedures used for foraminiferal Mg/Ca paleothermometry
Tập 4 Số 9 - 2003
S. Barker, Mervyn Greaves, H. Elderfield
The various cleaning steps required for preparation of foraminiferal samples for Mg/Ca (and Sr/Ca) analysis are evaluated for their relative importance and effects on measured elemental ratios. It is shown that the removal of silicate contamination is the most important step for the measurement of Mg/Ca ratios. In an example, bulk sample Mg/Ca decreases from 10.5 to 2.5 mmol mol−...... hiện toàn bộ
Đặc trưng đồng vị chính xác cao của các vật liệu tham khảo USGS bằng TIMS và MC‐ICP‐MS Dịch bởi AI
Tập 7 Số 8 - 2006
Dominique Weis, Bruno Kieffer, C. Maerschalk, Jane Barling, Jeroen de Jong, Gwen Williams, Diane Hanano, Wilma Pretorius, Nadine Mattielli, James S. Scoates, Arnaud Goolaerts, Richard M. Friedman, J. Brian Mahoney
Trung tâm Nghiên cứu Đồng vị và Địa hóa Thái Bình Dương (PCIGR) tại Đại học British Columbia đã tiến hành phân tích có hệ thống các thành phần và nồng độ đồng vị (Sr, Nd, và Pb) của một loạt vật liệu tham khảo của Cục Khảo sát Địa chất Hoa Kỳ (USGS), bao gồm basalt (BCR‐1, 2; BHVO‐1, 2), andesite (AGV‐1, 2), rhyolite (RGM‐1, 2), syenite (STM‐1, 2), granodiorite (GSP‐2), và granite (G‐2, 3)...... hiện toàn bộ
Nhiệt độ trong lớp manti môi trường và các cột nhiệt: Các ràng buộc từ bazan, picrit, và komatiit Dịch bởi AI
Tập 8 Số 2 - 2007
Claude Herzberg, Paul D. Asimow, Nick Arndt, Yaoling Niu, C. Michael Lesher, J. Godfrey Fitton, M. J. Cheadle, A. D. Saunders
Nhiều phương pháp đã được phát triển để đánh giá trạng thái nhiệt của manti dưới các sống núi đại dương, đảo, và cao nguyên, dựa trên thạch học và hóa địa chất của dung nham phun trào. Một phương pháp dẫn đến kết luận rằng nhiệt độ tiềm năng của manti (gọi là TP) của manti môi trường dưới các sống núi đại dương là 1430°C, giống như Hawaii. Phương pháp khác cho thấy các...... hiện toàn bộ
The pMELTS: A revision of MELTS for improved calculation of phase relations and major element partitioning related to partial melting of the mantle to 3 GPa
Tập 3 Số 5 - Trang 1-35 - 2002
M. S. Ghiorso, M. M. Hirschmann, Peter W. Reiners, V. C. Kress
We describe a newly calibrated model for the thermodynamic properties of magmatic silicate liquid. The new model, pMELTS, is based on MELTS [Ghiorso and Sack, 1995] but has a number of improvements aimed at increasing the accuracy of calculations of partial melting of spinel peridotite. The pMELTS algorithm uses models of the thermodynamic properties of minerals and the phase equilibrium algorithms of MELTS, but the model for silicate liquid differs from MELTS in the following ways: (1) The new algorithm is calibrated from an expanded set of mineral‐liquid equilibrium constraints from 2439 experiments, 54% more than MELTS. (2) The new calibration includes mineral components not considered during calibration of MELTS and results in 11,394 individual mineral‐liquid calibration constraints (110% more than MELTS). Of these, 4924 statements of equilibrium are from experiments conducted at elevated pressure (200% more than MELTS). (3) The pMELTS model employs an improved liquid equation of state based on a third‐order Birch‐Murnaghan equation, calibrated from high‐pressure sink‐float and shockwave experiments to 10 GPa. (4) The new model employs a revised set of end‐member liquid components. The revised components were chosen to better span liquid composition‐space. Thermodynamic properties of these components are optimized as part of the mineral‐liquid calibration. Comparison of pMELTS to partial melting relations of spinel peridotite from experiments near 1 GPa indicates significant improvements relative to MELTS, but important outstanding problems remain. The pMELTS model accurately predicts oxide concentrations, including SiO2, for liquids from partial melting of MM3 peridotite at 1 GPa from near the solidus up to ∼25% melting. Compared to experiments, the greatest discrepancy is for MgO, for which the calculations are between 1 and 4% high. Temperatures required to achieve a given melt fraction match those of the experiments near the solidus but are ∼60°C high over much of the spinel lherzolite melting interval at this pressure. Much of this discrepancy can probably be attributed to overstabilization of clinopyroxene in pMELTS under these conditions. Comparison of pMELTS calculations to the crystallization and partial melting experiments of hiện toàn bộ