Abstract:

Located on the Bohai seashore, the Xiaoshan volcano is the direct evidence of crustal activity on the western Bohai seacoast. The area is famous for its typicality, diversity and naturalness. With its unique scienti-fic significance, it is very rare in China. Due to the extensive Quaternary cover on the volcanic rocks, high-precision magnetic measurement was used to delineate the boundary of volcanic relics and to study typical geological structures. In this study, we described the magnetic field distribution characteristics of the Xiaoshan volcanic geological relics protected zone. Distribution range of the magmatic and sedimentary rocks in the zone was identified and their boundaries were delineated, and a number of faults were inferred. This is achieved through analyzing magnetic anomaly of the pole, upward extension, and the search for derivative and other processing methods. Our findings support that the high-precision magnetic method is effective to study the geological characteristics beneath the overburden area. The study of the magnetic field distribution features provides detailed and reliable basic data for the Xiaoshan volcano geological relics, and has important implications for the division of the geological relic landscape and for sensible planning of the protected zone.

Key words: Xiaoshan, Hebei Province, volcano, geomagnetic field, high-precision magnetic, fault