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Articles 1 - 4 of 4
Full-Text Articles in Physical Sciences and Mathematics
A Granger Causality Analysis Of Groundwater Patterns Over A Half-Century, Nitin K. Singh, David M. Borrok
A Granger Causality Analysis Of Groundwater Patterns Over A Half-Century, Nitin K. Singh, David M. Borrok
Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works
Groundwater depletion in many areas of the world has been broadly attributed to irrigation. However, more formal, data-driven, causal mechanisms of long-term groundwater patterns have not been assessed. Here, we conducted the first Granger causality analysis to identify the "causes" of groundwater patterns using the rice-producing parishes of Louisiana, USA, as an example. Trend analysis showed a decline of up to 6 m in groundwater level over 51 years. We found that no single cause explained groundwater patterns for all parishes. Causal linkages were noted between groundwater and area harvested, number of irrigation wells, summer precipitation totals, and drought. Bi-directional …
Extraction And Visualization Of Orientation Data From Virtual Geologic Surfaces With Matlab®, Avery J. Welker, John Patrick Hogan, Andreas Eckert
Extraction And Visualization Of Orientation Data From Virtual Geologic Surfaces With Matlab®, Avery J. Welker, John Patrick Hogan, Andreas Eckert
Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works
High-resolution visualization of surfaces of geologic interest, at a multitude of scales, using 3D point cloud technologies provides an opportunity to analyze spatial relationships of surfaces using orientation data. We present a MATLAB® script that produces planar geologic attitude data (e.g., strike, dip, and dip-direction data) from 3D datasets (e.g., point clouds, 3D scanning). The method utilizes Cartesian coordinates of triangular planar surfaces and converts them into matrices of conventional geologic attitude data. Spatial relationships among data points can be investigated, using polar tangent diagrams, stereographic analysis, or geologic curvature analysis. We utilize this script to create "synthetic" graphical plots …
A Metasomatized Lithospheric Mantle Control On The Metallogenic Signature Of Post-Subduction Magmatism, David A. Holwell, Marco Fiorentini, Iain Mcdonald, Yongjun Lu, Andrea Giuliani, Daniel J. Smith, Manuel Keith, Marek Locmelis
A Metasomatized Lithospheric Mantle Control On The Metallogenic Signature Of Post-Subduction Magmatism, David A. Holwell, Marco Fiorentini, Iain Mcdonald, Yongjun Lu, Andrea Giuliani, Daniel J. Smith, Manuel Keith, Marek Locmelis
Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works
Ore deposits are loci on Earth where energy and mass flux are greatly enhanced and focussed, acting as magnifying lenses into metal transport, fractionation and concentration mechanisms through the lithosphere. Here we show that the metallogenic architecture of the lithosphere is illuminated by the geochemical signatures of metasomatised mantle rocks and post-subduction magmatic-hydrothermal mineral systems. Our data reveal that anomalously gold and tellurium rich magmatic sulfides in mantle-derived magmas emplaced in the lower crust share a common metallogenic signature with upper crustal porphyry-epithermal ore systems. We propose that a trans-lithospheric continuum exists whereby post-subduction magmas transporting metal-rich sulfide cargoes play …
Modeling Land Subsidence Using Insar And Airborne Electromagnetic Data, Ryan G. Smith, R. Knight
Modeling Land Subsidence Using Insar And Airborne Electromagnetic Data, Ryan G. Smith, R. Knight
Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works
Land subsidence as a result of groundwater overpumping in the San Joaquin Valley, California, is associated with the loss of groundwater storage and aquifer contamination. Although the physical processes governing land subsidence are well understood, building predictive models of subsidence is challenging because so much subsurface information is required to do so accurately. For the first time, we integrate airborne electromagnetic data, representing the subsurface, with subsidence data, mapped by interferometric synthetic aperture radar (InSAR), to model deformation. By combining both data sets, we are able to solve for hydrologic and geophysical properties of the subsurface to effectively model the …