The Application Of Magnetic Prospecting In Hai Xing Plain, Hebei

According to aeromagnetic anomalies of Haixing Plain in Hebei, we select the appropriate method of magnetic survey data processing, analyse magnetic data of Haixing areas, and predict whether there is large deep mine on the eastern plain area of Hebei.Verified by drilling, we can announce that magnetic anomalies cause by the deep thick Archean metamorphic rock, which are geological conditions of metamorphic iron ore formatted. Based on the study of aeromagnetic anomalies, we divide the scope of ground magnetic anomaly, collect previous geological data and design ground magnetic survey field work; then collect and manage the field data, ascertain the physical property and make the correction of Diurnal sun variation and so on.Rendering the original magnetic anomaly contour map, on this basis, we determine the position center of the precise measurement profile and high-precision measurement. Then we analysis and process the magnetic data,combined prospecting experience of Shandong plain, to calculate the original anomaly on a variety of effective way.And combinated of drilling data,we determine abnormal body shape,depth and size by caused the magnetic anomaly and establish an integrated method to explorate in plain.In this paper, based on the geological data in the past and collected previous research results, we pretreat and analysis the magnetic data and define the abnormal cells in the abnormal areas.According to the mathematical and physical characteristics of magnetic anomalies, we make the necessary mathematical processing to the measured magnetic anomalies, to meet the needs of data conversion. By using gravity and magnetic processing software developed on the Chinese Development Research Center of Geological Survey, we process and convert the pretreated data, obtain the Multi-parameters information and deal with different aspects of each parameter, to assess results. As the exploration area in mid-latitudes,anomaly measured parameters isΔT,which is seriously affected by the oblique magnetization, we transformΔT intoΔZ⊥by geotropic pole approach,which is convertedΔT to the vertical magnetic anomaly in vertical magnetic case.Anomaly can be simplified and easy to explain;Second,we can treat the pole magnetic anomaly, to determine the optimum processing parameters.Through the tentative calculation,we find the best extension height;and dispose of gravity and magnetic anomalies, obtain Gravity and magnetic anomaly.Compared with the magnetic anomaly.We do something about gravity and magnetic anomaly corresponding analysis, determine the relevance and homologous of gravity and magnetic anomalies, to obtain the geological interpretation of the abnormal. Applied processing technology to magnetic anomalies,we do forward calculation and inverse calculation about human-machine interactive to the magnetic anomaly profile data of Precision measurements.Combined with regional geological and drilled data,we explain the center of magnetic anomalies on the Haixing inversion profiles,analysis the possibility of looking for deep deposits in Haixing plain.Inferred reasons caused by geological aeromagnetic anomaly,finally we establish the mode of integrated geophysical prospecting methods in plains.In this work area, Gaowan-Dashan magnetic anomaly zone mainly is caused by the relative enrichment of pyroxene metamorphic rocks which is the strong magnetic of the fault uplift. By the determination of magnetic drill core samples,we know that the Archean metamorphic rock magnetic is medium, the upward continuation results of magnetic anomaly and the aeromagnetic suggest that the deep anomaly source downward is very deep,and huge magnetic body. Comparison to Shandong Yandian aeromagnetic anomalies, Haixing magnetic anomaly and gravity anomaly overlap is less, that gravity and magnetic is different sources.It is projected that the plain bored deep mineralization is unlikely.