The application of downward continuation to deep mineral exploration: A case study of an ore district in Qinghai Province
SONG Shuang1, ZHANG Heng-Lei2
1. Exploration Institute, China National Offshore Oil Corporation Research Institute, Beijing 100027, China; 2. China University of Geosciences, Wuhan 430074, China
Abstract：In the exploration of deep concealed orebodies, the large distance between the iron orebody and the observation surface may produce only one broad magnetic anomaly which can't distinguish ore-related anomalies and background-induced anomalies. The application of upward continuation and derivatives fails to obtain satisfactory results. During the case study in Qinghai Province using downward continuation, the authors obtained the fine anomalies based on the downward continued field with a distance of 30 times that of the grid interval. The comparison of the downward continued field with many magnetite-bearing and non-magnetite-bearing drill holes revealed a clearer relationship between the magnetic anomalies and the ore-intersecting drill holes. It is also shown that all of the non-magnetite-bearing drill holes are located outside the downward continued field. Since it is possible to apply the stable downward continuation at present, the authors hold that the downward continuation of the anomaly with a large buried depth is useful in distinguishing superimposed anomalies and detecting the anomaly's location, thus providing evidence for planning the mining operations. The exploration accuracy is also discussed in this paper.
宋双, 张恒磊. 向下延拓在深部矿产勘探中的应用——以青海某矿区为例[J]. 物探与化探, 2014, 38(6): 1195-1199.
SONG Shuang, ZHANG Heng-Lei. The application of downward continuation to deep mineral exploration: A case study of an ore district in Qinghai Province. Geophysical and Geochemical Exploration, 2014, 38(6): 1195-1199.
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