Gravity and Magnetic Studies in the Tatun volcanic Region

Abstract

Gravity and ma gnetic surveys have been carried out in the Taton vol canic field in order to analyze the subsurface structures, the extension of the Chinshan Fault and the volcanic rock distribution in the surveyed area.Qualitative interpretation of gravity data indicates that the highest gravity zones are located in the Hengshantsun, Chihsingshan, Tatunshan, Mateng shan, and Chutzushan regions, whereas the lowest gravity anomaly is in the Yukuangkengt' ou region .. The inverted density/depth models are comparable to the surface geo logic characteristics. The density discontinuous zones are related to the Chin shan fault. The magnetic high anomalous areas, such as the Hengshantsun, Tatunshan, Chutzushan, Hsiaokuanyinshan, and Yangmingshan regions are also the gravity high regions except for the Chihsingshan region which, how ever, does show a low magnetic anomaly. Gravity and magnetic studies reveal comparable results. The geophysical anomalies support most of the major ge ological features presented in the studied area.

New Gravity and Magnetic Anomaly Maps in the Taiwan-Luzon Region and Their Preliminary Interpretation

“…This is probably due to the difficulty of the field work. However, a few magnetic data were collected on the periphery of Taiwan: the Coastal Plain in western Taiwan (Chang and Hu, 1981), the Pingtung Plain in southwestern Taiwan (Yu and Tsai,198 1), the Coastal Range of eastern Taiwan (Hu and Chen, 1986;Wu, 1991), the Ilan Plain of northeastern Taiwan (Yu and Tsai, 1979;Hsu et al, 1996a), and the Tatun volcanic region of northern Taiwan (Yang et al, 1994).…”

Geomagnetic Basement Relief of the Northern Taiwan Area

“…Because of interest in the seismicity, volcano activity, petroleum exploration, and geothermal resources, some studies, including gravity (Tzou and Yu 1987;Chen and Yeh 1991;Yang et al 1994), seismology (Chen . and Yeh 1991; 1995; Chen 1998), seismic (Wang et al 1994), magnetic (Yang et . ' al.…”