نوع مقاله : مقاله پژوهشی
نویسندگان
1 گروه مهندسی معدن، دانشکده معدن، دانشگاه صنعتی امیرکبیر، تهران ایران
2 گروه مهندسی معدن، دانشکده معدن، دانشگاه صنعتی امیرکبیر، تهران، ایران
3 گروه مهندسی معدن، دانکشده معدن، دانشگاه تهران، تهران ایران
4 گروه زمین شناسی، دانشکده زمین شناسی، دانشگاه باهنر کرمانف کرمان ایران
چکیده
کلیدواژه‌ها
موضوعات
عنوان مقاله [English]
نویسندگان [English]
Studied area is located in Kerman province. This area belongs to the URUMIA- Dokhtar magmatic arc zone. Several porphyry copper deposits were known in URUMIA- Dokhtar magmatic arc. UDMA is marked by voluminous Tertiary volcanic sequences of up to 3000 m thickness. It seemed that these Cu occurrences are related to structures, especially major and main faults. in this study magnetic structures were extracted by using of aeromagnetic data. This data was extracted by Atomic Energy Organization of Iran (AEOI) during 1977 and 1978. The flight lines distance and the sensor altitude were about 500 and 120 m, respectively. Airborne magnetic method is among the most efficient geophysical techniques for the detection of buried anomalies. In the first step, total magnetic intensity map was prepared. Then reduction to pole transformation was done on total magnetic intensity map. Reduction to the pole (RTP) is a standard part of magnetic data processing method, especially for large-scale mapping. RTP operation can transform a magnetic anomaly caused by an arbitrary source into the anomaly that the same source would produce if it is located at the pole and magnetized by induction only. Interpretation of magnetic data can further be helped by RTP in order to remove the influence of magnetic latitude on the anomalies, which is significant for anomalies caused by crust. Most of the studied areas are covered by mafic volcanic rocks. These rocks produce moderate to high magnetic anomalies. In some parts, the effect of demagnetization can be observed in these rocks. which is due to the spread of alteration in this area. A low magnetic anomaly is observed in the northern part of the studied area. which is related to sedimentary rocks in this area. Next, body magnetic anomalies were extracted from reduction to pole map. Tilt angle filter was used to extract magnetic lineaments. Tilt angle is defined as the arctan value of the ratio of the vertical derivative of the potential field to its horizontal derivative. A tilt angle filter was applied to the reduction to pole data. Upward continuation filter was implemented at 200 m, 500 m and 1000 m on the tilt angle map. Then magnetic lineaments were extracted from tilt angle maps. Several magnetic lineaments and magnetic bodies were extracted from magnetic maps (tilt angle maps and reduction to pole maps). There is good correspondence between magnetic structures and copper occurrences. The P-A curve confirms this result.
کلیدواژه‌ها [English]
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