The report of aerial geophysics studies in method of magnetometry and radiometry in Chapan sheet

States KHORASAN SHOMALI
Author Engineer Abdolfatah Hesami
Publisher gsi
Published At 11 April 2000

Summary

Magnetic data are used for better recognition of geological structures and for informing of lithologic changes in the regions without exposure and better relation to them in the regions which have a little our crop. Magnetic data without consideration to weathering of rocks give important data about location of faults which area suitable environment movement of mineralization solution and characterizes more precise position and extent of buried intrusive masses and also they will appear geological structures are visible with direct viewpoint with aerial photo.

Description

Introduction Magnetic data are used for better recognition of geological structures and for informing of lithologic changes in the regions without exposure and better relation to them in the regions which have a little our crop. Magnetic data without consideration to weathering of rocks give important data about location of faults which area suitable environment movement of mineralization solution and characterizes more precise position and extent of buried intrusive masses and also they will appear geological structures are visible with direct viewpoint with aerial photo. Also he weathered regions which are suitable place for concentration of ore deposits due to ruining of magnetite mineral with detectable magnetic information. Magnetic aerial information should be as suitable magnetic maps (image and perpendicular gradient) and they have been explanted systematically because this information will not help to solve of geological problem of the region individually. Correlation of magnetic irregularities with sulfide minerals in the region should be characterized. Examining of magnetic irregularities with lithologic units in the region and also relations of these units to mineralization, new magnetic ground measurements, measurement of magnetic properties, sample gathering from out cropped region and collecting of sample from the regions without overlap along profiles that we can comprise lithologic change from magnetic data to geological mapped changes, is necessary with this work, the problems resulted from a little exposure, extent of weathering and deep development of rocks will low removed and correlation of magnetic information to mapping geology will be used in regions without exposure. A precise geological map of the region usually not only for exploration of mineral resources of metals with value likes gold and copper is very important but also from ground water aspect, agriculture, engineering destinations and industrial minerals are precise too. Magnetic information in aspect of non dependence to exposure, weathering and coverage for obtaining geological information, structural and explorations of metal resources, as systematically in Canada, Australia, India and other countries are used which is used nowadays seriously from this method and a sample of its usage can be seen in this report. Using of magnetic information, for direct searching that during that, magnetic reply and are special geological aim is evaluated, is used and is generally in exploration and gold, aim of mineralized system which contains magnetite or pyrotite and with using of magnetic information can be traced directly. Seeking out and identification of a special geological unit, an important contact or  structural impermanent are other cases which are used by magnetic information in this direct seeking out. Magnetic information should have high quality in usage of this method. Even in cases which rocks have considerable out crop, magnetic information of borders, trend of units in rocks group and important disconformity in exposure, resulted from faults. In the regions where they have less exposure of weathering and surface coverage they become barrier from direct vision. These information connect between lithologic units with more certainty, Main aims of this plan are: Identification of magnetic units in aspect of type of lithology and relation of that to mineralized in the region. Identification of modern intrusive masses. Finding of lineation and faults which are suitable locations for mineralizing. Determination of promising regions in aspect of aerial geophysics. and also main aims of using these radiomerty data are: * Determination of lithology and detectable structures from radiometry data. * Alteration * Identification of introduction and high potential from radiometric aspect.