REGIONAL MAGNETIC DATA ANALYSIS FOR METALLIC ORE DETECTION WITHIN STRUCTURAL ASSEMBLAGES OF MUSLIM BAGH OPHIOLITE BELT BALOCHISTAN

Abstract

The application of regional magnetic survey is a key geophysical technique utilized to detect subsurface magnetized zones that hold potential for exploratory purposes. In the domain of geophysics, the detection of anomalous magnetization has the potential to suggest the presence of localized mineral deposits, which could hold economic importance. Hence, an assessment and analysis were conducted on a dataset comprising magnetic measurements obtained from the Muslim Bagh ophiolite region located in Balochistan. The Muslim Bagh ophiolite belt comprises many ophiolite zones that delineate the boundary separating the Afghan block of the Eurasian plate from the Indian plate. During the Late Cretaceous period, the ophiolites accreted onto the Indian continental margin. The purpose of the investigation was to ascertain and pinpoint areas of anomaly within the specified study area. The study site is situated in a latitude of 30 degrees, 49 minutes, and 27 seconds North, and a longitude of 67 degrees, 44 minutes, and 2 seconds East, within the ophiolitic belt of Muslim Bagh. A total of 1012 magnetic measurements from toposheets 34N/9 and 34N/13 were utilized for the purpose of study. The data were collected using a Proton Precession Magnetometer G-856AX. The collected data are presented in the form of 2D contour magnetic anomaly maps and total magnetic intensity (TMI) maps. Additionally, a 3D anomaly map was created to aid in the qualitative interpretation of the data. The field data were analyzed using Surfer and Geosoft software, which allowed for the creation of two cumulative maps: one for magnetic anomaly and one for total magnetic intensity (TMI). These maps revealed the presence of two distinct magnetic anomalous zones within the study area. The area under consideration exhibits a significant level of anomaly, as evidenced by the magnetic anomaly values recorded, which range from 520 to 2480 nanotesla. The other low anomalous zone exhibited magnetic field values ranging from -40 to -600 nanotesla. A cumulative total magnetic intensity (TMI) map was created, which identified and emphasized two magnetic zones (one high and one low) in order to validate the anomalous zones indicated on the cumulative magnetic anomaly map. The TMI values of the high magnetic zone exhibited a range between 48620 nT and 50540 nT. The observed higher magnetic readings are indicative of the presence of metallic mineralization. The TMI v values of the low magnetic zone exhibited fluctuations ranging from 47500 nT to 47980 nT, indicating the absence of magnetic properties in the subsurface. The high magnetic anomaly zone is observed to extend from toposheet 34N/9 to 34N/13 in a southwest to northeast direction. Additionally, the overall intensity map was divided into maps depicting regional anomalies and residual anomalies. The residual anomaly map underwent processing, incorporating several properties including Reduction to Equator, Vertical and Horizontal derivatives, and upward continuation. These techniques were employed to accurately identify anomalous zones and enhance the understanding of magnetic data. Therefore, the utilization of integrated geophysical techniques and thorough investigations can yield vital information regarding the identification of promising zones and the spatial distribution of magnetic minerals within the designated study region.