Exploration Project of Minerals in the South of Khorasan
This sheet is located in southern Khorasan province at longitudes 59? to 59?30' E and latitudes 31?30 to 32? N.
In this area the igneous, sedimentary and metamorphic lithology units related to the upper cretaceous to Neogene, especially Shahkouh granite having extensively covered this sheet, outcrop. Metamorphic rocks along with ophiolite complexes and metamorphic complex of Dehsalm with indefinite age including schist, metamorphosed tuffs, hornfels, migmatite, diabase and metamorphosed ultrabasic rocks are the oldest outcropped lithology units in the study area. Younger lithology units covering the existing units are sandstone, shale, andesite and limestone of Triassic-Jurassic, granite of Jurassic-Cretaceous, conglomerate, limestone, sandstone and marlstone of lower Cretaceous, conglomerate, limestone, marlstone and sandstone of Upper Cretaceous, sandstone, conglomerate, limestone, tuff, agglomerate, andesite of Paleogene, conglomerate, clay, andesite and basalt of Neogene, acidic and intermediate intrusive rocks of Tertiary and finally alluviums and salt flats of Quaternary.
In this sheet, 585 geochemical samples were taken and analyzed for 20 elements of Co, Cr, Ni, Ti, Mn, Sr, Ba, Au, Fe, As, Sb, Bi, Hg, W, Cu, Pb, Mo, Sn, Ag and Zn. Then the accuracy of analyses was evaluated using Thompson control diagram and calculating the relative error. Afterwards all data was processed with the help of computer software in such a way that first, statistical parameters related to the raw data were calculated and next, equal lithology communities were separated. Each community was normalized in proportion to the mean values of the same community for obtaining the values of elements` enrichment index and then enrichment index data was normalized. By means of monovariable and multivariable statistical techniques like elements` correlation coefficient, cluster analysis and factor analysis, the data was analyzed and out of order values were studied. Monovariable maps were drawn using network estimation technique for enrichment index data (the total number of the maps has been 36 sheets). In addition, anomalous areas resulting from factor analysis method were specified and indicated.
Subsequently, anomalous areas coming from geochemical data were introduced. In order to control introduced anomalies, to specify different elements` creation phase and to distinguish actual anomalies from false ones, the method of heavy mineral studies was applied. Heavy mineral was taken in the area of preliminary geochemical anomalies and then its data was processed. In the end, 12 areas were introduced as final anomalous areas and anomalies based on their compatibility rate with a certain type of ore deposits were modeled to conduct the probable exploration operation to be done in that area.
The following is the introduction of the mineral promising areas according to the geochemical studies: