One of the measurement geophysical methods to investigate kimberlite pipes is by using the magnetic method. The acquired field data in this study uses <span style="font-family:Verdana;">two proton-prec...One of the measurement geophysical methods to investigate kimberlite pipes is by using the magnetic method. The acquired field data in this study uses <span style="font-family:Verdana;">two proton-precession magnetometers for the mapping of magnetic anomalies</span><span style="font-family:Verdana;"> due to kimberlites. Three different magnetic maps are obtained from the result of total magnetic field data processing on Oásis Montaj software programme. These maps include magnetic anomaly maps through statistical analyses, total magnetic field intensity map and map of the analytic signal. Based on the interpretation of these maps a structure is identified with SWW-NEE directions in which magnetic signatures that indicate the presence of kimberlite pipes are observed. As the interpretation of the magnetic anomalies is a complicated process due to their dipolar nature, the analytic signal is generated, where is possible to observe the typical shape of these anomalies.</span>展开更多
High-resolution aeromagnetic data of parts of Middle Benue Trough, Nigeria (sheets 212, 213, 233 and 234) was interpreted by applying source Parameter Imaging (SPI) and Spectral Depth analysis with the aim of mapping ...High-resolution aeromagnetic data of parts of Middle Benue Trough, Nigeria (sheets 212, 213, 233 and 234) was interpreted by applying source Parameter Imaging (SPI) and Spectral Depth analysis with the aim of mapping out the magnetic lineaments and analysing magnetic signals coming from different sources. The results from the derivatives maps show major and minor lineaments trends in the NE-SW and NW-SE directions respectively. Results from SPI show the maximum sedimentary thickness of about -4546.7 m (-4.5467 km) around the region of Awe, Aman, Langtang south, Gassol and the north-eastern part of Donga. Minimum depth of -167.9 m (-0.1679 km) around the region of north of Shendam, north of Wase, north-eastern part of Aman, Bantaji, Donga, Ibi and Bali. The residual map was divided into twenty-five sections. Spectral Depth was run for each of these twenty-five sections, the result shows that the depth to the deep magnetic source ranges between -0.65 km and -3.35 km. The depth to the shallow magnetic sources ranges between -0.03 km and -0.44 km showing the presence of magnetic intrusive bodies within the sediments. Since the sedimentary thickness of 3.0 km and above is only sufficient for hydrocarbon maturation and accumulation, then the results from this present study show that the study area might be sufficient enough for hydrocarbon maturation and accumulation.展开更多
文摘One of the measurement geophysical methods to investigate kimberlite pipes is by using the magnetic method. The acquired field data in this study uses <span style="font-family:Verdana;">two proton-precession magnetometers for the mapping of magnetic anomalies</span><span style="font-family:Verdana;"> due to kimberlites. Three different magnetic maps are obtained from the result of total magnetic field data processing on Oásis Montaj software programme. These maps include magnetic anomaly maps through statistical analyses, total magnetic field intensity map and map of the analytic signal. Based on the interpretation of these maps a structure is identified with SWW-NEE directions in which magnetic signatures that indicate the presence of kimberlite pipes are observed. As the interpretation of the magnetic anomalies is a complicated process due to their dipolar nature, the analytic signal is generated, where is possible to observe the typical shape of these anomalies.</span>
文摘High-resolution aeromagnetic data of parts of Middle Benue Trough, Nigeria (sheets 212, 213, 233 and 234) was interpreted by applying source Parameter Imaging (SPI) and Spectral Depth analysis with the aim of mapping out the magnetic lineaments and analysing magnetic signals coming from different sources. The results from the derivatives maps show major and minor lineaments trends in the NE-SW and NW-SE directions respectively. Results from SPI show the maximum sedimentary thickness of about -4546.7 m (-4.5467 km) around the region of Awe, Aman, Langtang south, Gassol and the north-eastern part of Donga. Minimum depth of -167.9 m (-0.1679 km) around the region of north of Shendam, north of Wase, north-eastern part of Aman, Bantaji, Donga, Ibi and Bali. The residual map was divided into twenty-five sections. Spectral Depth was run for each of these twenty-five sections, the result shows that the depth to the deep magnetic source ranges between -0.65 km and -3.35 km. The depth to the shallow magnetic sources ranges between -0.03 km and -0.44 km showing the presence of magnetic intrusive bodies within the sediments. Since the sedimentary thickness of 3.0 km and above is only sufficient for hydrocarbon maturation and accumulation, then the results from this present study show that the study area might be sufficient enough for hydrocarbon maturation and accumulation.
