INTERPRETASI STRUKTUR PENGONTROL MUD VOLCANO BLEDUG KUWU DI WILAYAH KECAMATAN KRADENAN, KABUPATEN GROBOGAN, JAWA TENGAH MENGGUNAKAN ANALISIS DATA ANOMALI MAGNETIK LOKAL; INTERPRETATION OF BLEDUG KUWU MUD VOLCANO’S CONTROL STRUCTURE IN KRADENAN SUBDISTRICT, GROBOGAN, CENTRAL JAVA USING OF LOCAL MAGNETIC ANOMALY DATA ANALYSIS
Al Firman, Wahyudi
2015 | Disertasi | FMIPA UGMGeophysical research by using magnetic method has been done in order to reconstruct mud volcano subsurface structure in Kradenan, Grobogan, Central Java. This measurement consisted of 118 magnetic station in the area 8 km x 8 km with spacing 0,7 km – 1 km. The measurement used a Proton Precession Magnetometer (PPM) G856. The position and elevation points were measured by Global Positioning System (GPS). Data processing is started by IGRF correction and daily variation correction to get total magnetic anomaly field. The anomaly is reduced to the pole and upward continuated until 1200 m height. The contour of the local magnetic field anomaly is analyzed qualitatively. The quantitative interpretation is done by using Mag2DC modelling. Based on the results of the qualitative interpretation, it shows that the structure controling the Bledug Kuwu Mud Volcano is normal fault which has a trend from southwest-northeast. The result of the quantitative interpretation is indicates that the subsurface structure that controls the Bledug Kuwu Mud Volcano composed by claystone with susceptibility 0,0005 (cgs), limestones with susceptibility 0,0011 (cgs) and alluvium with susceptibility 0,0001 (cgs).
Kata Kunci : Mud volcano; geology structure; magnetic field anomaly.
