Using Magnetic Method for the Identification of Anomalies Due to Kimberlite Pipes, Luando Area, Bié, Angola
- 1 Department of Geosciences, Instituto Superior Politécnico de Tecnologias e Ciências (ISPTEC), Talatona, Luanda, Angola
- 2 Department of Geophysics, Universidade Agostinho Neto (UAN), Camama, Luanda, Angola
- 3 Department of Geophysics, Universidade Agostinho Neto (UAN), Camama, Luanda, Angola
Abstract
One of the measurement geophysical methods to investigate kimberlite pipes is by using the magnetic method. The acquired field data in this study uses two proton-precession magnetometers for the mapping of magnetic anomalies 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.
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