Geological and geophysical exploration of Saghand iron deposit

Document Type : Research Article

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Abstract

The Saghand Iron Ore is a type of magnesian skarn deposit formed by the intrusion of granitic igneous bodies of Jurassic into carbonate rocks. Four lithological units of micaschist, gneiss, skarn and limestone are present in the area. On the basis of the RTP magnetic map, three magnetic anomalies A, B and C are present in the area. The first vertical gradient map shows that anomaly A has shallow and near surface sources as part of it correlates with iron outcrop. Anomaly B which correlates with the alluvium shows also shallow sources in the western portion on the first vertical gradient map but the eastern portion of anomaly B has no responses. Anomaly C which also correlates with the alluvium, has no responses on the vertical gradient map. Considering the upward continued map, it is inferred that only anomaly A and the western portion of anomaly B have deep responses and their sources are possibly iron mineralization at depth. Due to the high magnetic susceptibility of magnetite in iron ores relative to the other rock units, the best causative source of the western portion of anomaly B which correlates with the alluvium can be magnetite in the covered iron bodies. Two anomalies are present in gravity data. Considering the first vertical and continued maps, the first priority of drilling is recognized over anomaly A which correlates with an iron ore outcrop. The second priority of drilling is identified over the western portion of anomaly B which correlates with the alluvium. This drilling results are consistent with the responses of the first vertical gradient and continued maps and confirm them.
 

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References

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Iranian Journal of Geophysics
Volume 7, Issue 1
June 2013
Pages 116-132

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