Geochemistry and Mineralogy of Sardhi Formation and Related Rocks of the Salt Range, Punjab

Abstract

Research on Sardi Formation and Warchha sandstorm was planned due to old reports of copper occurrence in these rocks. It was also realized that Sardi Formation is top of the Permian Nilawahn Group. The later has Tobra Formation of glacier origin at its base succeeded by Dandot Formation. The Permian is well known to mark the period of continental rifting of the Indo-Pak plate with the rift basin receiving sedimentation. In the Permian time, the sedimentation is known to be derived from south although in Mesozoic the direction of sedimentation was reversed. In the first phase of the project, Warchha sandstone and Sardhi Formation were systematically sampled and studied in the laboratory. It was found that copper mineralization was more common in the Sard Formation but was rather sparce in the Warchha sandstone Therefore in the second phase of the project the work was concentrated on the Sard Formation. The present report covers both phases of research and give a combine presentation. The research was mainly based on field studied involving sampling from measuring section, petrographic analysis with advance optical method, mineral separation and their studied, chemical analysis, trace element analysis, radiometric studied, X-Ray Diffraction analysis and all other techniques were utilized which appeared necessary. Among major result of the studied, it was found that monotonous Sardi Formation has lithologic banding shown by variation minerals, textural and chemical variation. The clay minerals show a variety and peculiar association. Zeolites had also developed locally as tiny grains but also as thin veins. Copper minerals occur as nodules with core containing native copper surrounded by secondary copper mineral and some iron mineral as well. Regionally copper mineral is concentrated in the eastern part of the Sardi Formation locally they make with high concentration. Another apartment result was the present of barium generally could association with copper mineral. There is no anomaly radio-activity in the entire section of the Sardi Formation and the Warchha Sandstone. This study, the first of its kind of this important formation. Proved that the Sardi Formation derived from the Volcanic material which could have been also the source of copper mineral which could have been also the source of copper mineral as native cooper is known to occur in such formation. This mean that systematic studied should also be carried out in the central zone of Salt Range. In the addition structural studied should also be included to find/influences of rift tectonics because if such zones ae properly deliniated, it can provide an important frame work for mineral prospecting in the Salt Range. A regular field mapping combine with laboratory study can help locating the economically rich zone of the Sardi Formation.