Magnetic Field Characteristics in the Jiaozhou Bay and Their Engineering Geology Significance

Based on the magnetic survey data in the Jiaozhou Bay, the magnetic anomaly map was plotted. It is shown from the map that the central and northern Jiaozhou Bay is a positive magnetic anomaly area with gentle variations in magnetic anomaly and gradient; the western bay is a strong banded variant magnetic anomaly area with a banded distributions of alternate postive and negative magnetic anomalies; the magnetic anomaly in the northeastern Jiaozhou Bay shows a patchy distribution and is mainly positive anomaly; and the southern survey area is a mixed magnetic anomaly area with the magnetic anomaly in the middle Jiaozhou Bay showing near east-westly trending banded distributions and that in the southern Jiaozhou Bay showing NE trending alternate positive and negative anomaly distribution. It is shown from above-mentioned magnetic anomaly phenomena that the fault structures is the Jaozhou Bay are well developed, the NW and near east-westly trending faults against the NE trending fault structure background can be identified in the magnetic anomaly distribution map, and these faults can bring about unfavorable effects on the engineering construction in the Jiaozhou Bay.