Abstract
A detailed magnetic survey has been carried out in the northern Taiwan area in order to determine the topographic surface of the magnetic basement. This survey covers an area of about 900 km2, and totally the observation point is 269. After geomagnetic corrections of the observed data, the magnetic anomaly map was obtained. For the purpose of resolving the deeper (relative to the shallow effects) magnetic basement, a low-pass filter was applied to the magnetic anomaly to obtain a smoothed magnetic anomaly. Thirteen profiles were designed to cross and cover evenly the smoothed geomagnetic anomaly in the study area. These geomagnetic anomaly profiles were inverted to obtain the magnetic basement profiles by trial and error method. Compiling these 1-D magnetic basement profiles, we outlined the 2-D magnetic basement relief. The pattern of the relief of the geomagnetic basement shows that the depth is ranged from 2.6 to 6 km. There exists a basement high under the Tatun volcano area. Compiling with the topographic relief, we can find that they correlate to each other well, except for a contravention in the mountainous area surrounding the Taipei basin. This converse can be explained by supposing that tectonic forces lifted the mountainous area after the basement was formed. In order to verify the “truth” of the solution, we calculated the theoretical geomagnetic anomaly using the model we have inverted. Comparing the result with the observed geomagnetic anomaly map, we can find that they are quite similar to each other, with only a small variance.
Highlights
A regional magnetic survey covering an area of about 900 km2 has been conducted in the TAO, Vol 1 2, No 3, September 2001 northern Taiwan area
A magnetic anomaly map is certainly important to investigations of regional tectonics by providing information in geological boundaries and the volcanic nature of underlying sources
A detailed magnetic survey has been conducted in the northern area of Taiwan to infer the magnetic basement
Summary
A regional magnetic survey covering an area of about 900 km has been conducted in the. A magnetic anomaly map generally provides fundamental reconnaissance of a geological province. These maps yield basic information reflecting the physical properties of the underly ing rocks or sediments. A magnetic anomaly map is certainly important to investigations of regional tectonics by providing information in geological boundaries and the volcanic nature of underlying sources. The objective is to describe the boundary between sedimentary basins and surrounding areas where the basement is shallow. Such information can often be obtained by visual inspection of a magnetic map. Forward modeling is a basic approach to the interpretation of the underlying magnetic bodies. Algorithms using the generalized analytic signal to determine the depth to magnetic source developed by Hsu et al (1996) were applied to do the profile and surface modeling
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
