Exploring Placer Gold Deposits through Integrated Geophysical and Geochemical Techniques at the Confluence of the Indus and Kabul Rivers, NW Pakistan

Abstract

Analysis of the anomalous magnetic mineral intensities and geochemistry for placer gold deposits are presented for those of the Attock area at the confluence of the Indus and Kabul rivers in northwestern Pakistan. Two grids covering an area of 10x18 m 2 and 8x10 m 2 were analyzed using a G-858 Cesium Vapor Magnetometer. The anomalous zones obtained were plotted on contour maps, 2D and 3D magnetic intensity maps. Based on the magnetic anomalies, grid-1 of the study area was sampled at three different anomalous zones for geochemical analysis. These zones contain gold concentrations, ranging from 2.11 ppm to 6.109 ppm with an average of 4.01 ppm. Increase in gold concentration in the subsurface within the anomalous zones indicates that magnetometer survey followed by a geochemical analysis can potentially narrow down the gold-bearing anomalous zones.

Petrographic and Geochemical Analysis of Indus Sediments: Implications for Placer Gold Deposits, Peshawar Basin, NW Himalaya, Pakistan

“…The BBC consists of heterogeneous gneisses, quartzofeldspathic gneisses, amphibolites, granodiorites, pegmatites, quartzite, metacarbonate sedimentary rocks, and leucocratic granites [25]. The Peshawar Basin is an intermontane basin located on the Indian Plate in the LH, along the southern edge of the Pakistan Himalaya [5,23]. This intermontane basin originated in the Plio-Pleistocene during the late stages of orogenetic episodes caused by The Peshawar Basin is an intermontane basin located on the Indian Plate in the LH, along the southern edge of the Pakistan Himalaya [5,23].…”

“…The Peshawar Basin is an intermontane basin located on the Indian Plate in the LH, along the southern edge of the Pakistan Himalaya [5,23]. This intermontane basin originated in the Plio-Pleistocene during the late stages of orogenetic episodes caused by The Peshawar Basin is an intermontane basin located on the Indian Plate in the LH, along the southern edge of the Pakistan Himalaya [5,23]. This intermontane basin originated in the Plio-Pleistocene during the late stages of orogenetic episodes caused by Indian-Eurasian plate collisions [24,28,29].…”

“…It is responsible for the sediment accumulation in the Attock-Cherat Range and causes pounding drainage [28]. Exposed igneous and metamorphic rocks eroded from northern Pakistan have the potential to provide primary gold in the Himalaya that can be deposited mostly via river systems [5]. These depositions may consist of scattered economic gold clusters deposited by gravity settling [29,30].…”

“…Gold is one of the most valuable minerals on the planet, consisting mostly of elemental gold with traces of mercury, silver, copper, iron, nickel, manganese, and tinier amounts of selenium, platinum-group metals, bismuth, and rhenium [1][2][3][4][5]. When the gold is about 4 g/ton with other accumulated deposits, it is included in mineral deposits [6].…”

“…As they influence the flow of water, features such as canyon exits, waterfalls, and point bars may change its accumulation in the same place. The aforementioned characteristics substantially reduce water velocity and may be good places for the deposition of heavy minerals, such as gold grains [5].…”