Geosciences Research

Download PDF (236.8 KB) PP. 93 - 99 Pub. Date: May 15, 2017

DOI: 10.22606/gr.2017.22003

• P K Yadav^*
  Consultant Geologist

In the recently drilled deeper boreholes by HZL new intersection of lead and zinc ores have established depth ward continuity of ores of previous boreholes and have thus augmented reserves considerably. It has suggested revision of ore forming concepts and also that in the Rajpur Dariba area further search for Zn-Pb should be carried out using new innovative techniques. Success often requires supplementing standard procedures with the effective use of new exploration methods: the kind that can see deeper, are more definitive, and more efficient to ore discovery. The conventional methods have their place, but these are proving to be less effective as new terrains are increasingly more difficult to explore. Present studies have helped in searching new controls of mineralisation and in formulation of new ore guides for future search of new ore bodies. On the basis of present studies like facies of volcano-sedimentary sequence, textures, structures, ore microscopy, environment of ore deposition, characters of mineralisation, ore facies, sequence stratigraphy, airborne and ground geophysics new evidences for ore genesis have been collected. In Sindesar Khurd these studies have suggested vent complex type of hydrothermal sedex deposit. Rajpura Dariba deposit displays biphase mineralisation including stratiform sulphides and post metamorphic epigenitacally melt introduced independently. Salient features of vein ores such as occurrences as pods, segregation veins or open space fillings traversing the banded ores, absence of deformation and recrystalisation textures indicate that these veins are post-metamorphic and could have formed from a different ore fluid. The cavity filling nature of vein ore and their occurrence in irregular shear planes suggest their environment of ore formation was different than imprints of metamorphism in banded ores. The source of this fluid could be intrusive granite located during present studies. Now with an objective of searching new ore zones more evidences like faults and shear zones which are loci for ore in volcanoclastic rocks and calc silicate marble is the best host. Other evidences of ore forming processes and characters of volcanic rocks are also helpful in ore search. These strategies are discussed in this paper to search new local targets for selecting new drill sites.

Rajpur-Dariba, volcano-sediments, volcanic textures, faults, ore guides, new ore bodies, alteration, zoning, hydrothermal, bimodal

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