Case study: joint seismic refection and CSAMT data interpretation for mineral explorations in Fujian, China

• Autorzy: Liu Guofeng , Meng Xiaohong , Tan Handong , Chen Zhaoxi , Ni Jianhui , Liu Lanbo

Identyfikatory

DOI

10.1007/s11600-020-00477-2

• Języki publikacji: EN

Abstrakty

EN

The Southwestern area of Fujian Province in China contains a major metallogenic belt. There have been three major tectonic movements since the Late Paleozoic, and the thrusts here are the main mineral deposits. These occurred between the Early Carboniferous and Late Permian eras. Due to dramatic undulations in the surface and associated complex underground structures, a single geophysical method cannot provide reliable imaging results. This is largely due to difculties in data acquisition and processing. Seismic exploration provides one example. Using this method, raw shot gathers have a low signal-to-noise ratio because of the undulations in the topography. Furthermore, strong lateral velocity variation makes the migration process exceedingly difcult. This means that interpretations of the resulting refection seismic profle give rise to uncertainty. For this reason, two-dimensional refection seismology and controlled source audio-frequency magnetotel lurics (CSAMT) electromagnetic sounding techniques were performed. After initially completing conventional processing on the seismic refection data, subsequent pre-stack depth migration (PSDM) over the rugged topography yielded a much better image. It was able to identify thrust faults and magma intrusions. Then, using CSAMT, inversion was conducted with the same topography as the seismic refection. By combining the migrated seismic profle, inverted resistivity profle, and borehole data, a vertical geological model was constructed. This proved the existence of an overlapped thrust, and it also indicated the possible presence of deeper mineralization.

Słowa kluczowe

EN

CSAMT; mineral exploration; seismic reflection; thrust; joint interpretation; PSDM on rugged topography

PL

CSAMT; poszukiwanie kopalin; sejsmika refleksyjna; napór

• Wydawca: Instytut Geofizyki PAN ; Springer
• Czasopismo: Acta Geophysica
• Rocznik: 2020
• Tom: Vol. 68, no. 5
• Strony: 1373--1385
• Opis fizyczny: Bibliogr. 28 poz.

Twórcy

autor

Liu Guofeng

• School of Geophysics and Information Technology, China University of Geosciences, Beijing 100083, China

autor

Meng Xiaohong

• School of Geophysics and Information Technology, China University of Geosciences, Beijing 100083, China

autor

Tan Handong

• School of Geophysics and Information Technology, China University of Geosciences, Beijing 100083, China

autor

Chen Zhaoxi

• School of Geophysics and Information Technology, China University of Geosciences, Beijing 100083, China

autor

Ni Jianhui

• The Eighth Geology Team of Fujian Province, Fujian, China

autor

Liu Lanbo

• Integrative Geosciences Center, University of Connecticut, Mansfeld, CT 06269, USA

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