Geophysical Characterization of Lamproite Fields in the Dharwar Craton Using VLF-EM and Advanced Filtering Techniques: Insights from Conductivity Analysis and Analytical Signal Mapping
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引用次数: 0
Abstract
This study presents a geophysical investigation of the lamproite fields located in the Dharwar craton, aiming to map conductivity variations using contemporary techniques. The study employs very low-frequency electromagnetic (VLF-EM) methods, applying Hilbert transformations and first-order vertical derivatives to the Fraser and Karous-Hjelt filtered contoured of VLF-EM data. The Peninsular Gneissic Complex (PGC) granitic rocks in the study area experienced tectonic forces, resulting in fractures along specific WNW-ESE to NW-SE trends. Within these crustal weak zones, these lamproites are emplaced. The lamproite pipes are volcanic rocks. Hence, the top portions are weathered and tend to conductive, and the conductivity tend to decreases with the depth. The volumetric size of lamproites ranges from centimetres to hundreds of meters, unlike kimberlites, which are larger. Hence, the exploration of lamproites poses challenges. The contours of in-phase and quadrature components were used to identify the cluster of lamproite zones within the study area. From this study, the boundaries of the lamproite pipes were clearly identified using real component's analytical and first-order vertical derivative signal contour maps. The VLF-EM pseudo depth current density section was used to identify anomalous lamproite, pipes, and their subsurface extensions, along with the surrounding formations. The current investigation findings specify that the lamproites exhibit weak conductive. These results provide valuable insights for exploration efforts within the Dharwar craton, and can aid in the identification and mapping of the lamproite fields.
期刊介绍:
Accounts of Chemical Research presents short, concise and critical articles offering easy-to-read overviews of basic research and applications in all areas of chemistry and biochemistry. These short reviews focus on research from the author’s own laboratory and are designed to teach the reader about a research project. In addition, Accounts of Chemical Research publishes commentaries that give an informed opinion on a current research problem. Special Issues online are devoted to a single topic of unusual activity and significance.
Accounts of Chemical Research replaces the traditional article abstract with an article "Conspectus." These entries synopsize the research affording the reader a closer look at the content and significance of an article. Through this provision of a more detailed description of the article contents, the Conspectus enhances the article's discoverability by search engines and the exposure for the research.