Geology topics

Karl W. Stauffer

Publications and source records attributed to Karl W. Stauffer.

4 recordsLinked to original sources

USGS1975

Heavy mineral prospecting in Pakistan

Heavy-mineral prospecting is a method of tracing potential ore minerals to their source by systematically examining the heavy minerals of stream sands. The heavy minerals are partially concentrated in the field by panning. In the laboratory the heavy minerals are further concentrated by floating off the quartz and feldspar in a heavy liquid, such as bromoform, having a specific gravity of 2.89. Magnetite is separated magnetically and scheelite is identified under short-wave ultraviolet light. To obtain quantitative results on the minerals present, the sample is reduced by coning and quartering, mounted on a slide in oil, and a count of a minimum of 250 grains made. The chi square test applied to the splitting and counting techniques shows them to be statistically valid. The properties of some heavy minerals most useful for their rapid identification are listed. Methods here described are those utilizing a minimum of field and laboratory equipment and may be appropriate for application in many areas of the world.

Open-File Report↗

USGS1975

Heavy minerals in stream sands of the southern Hazara District, Pakistan

The areal distribution of heavy minerals in 99 samples from stream sands in the southern Hazara District, West Pakistan, indicates that the metamorphic grade of the rocks in the area increases toward the northwest. Minerals of potential economic value in the heavy-mineral samples include scheelite from the Oghi-Batgram-Battal area and hematite from the Galdanian area. The total weight of magnetite sand grains transported down the Indus River past Darband is calculated to be about 200,000 tons per year, a quantity which may be of economic value. Radioactive minerals are not present in any of the samples in sufficient quantity to be of economic importance.

Hazara District↗

USGS1969

Devonian laterite in Chitral state, West Pakistan

A Devonian laterite has recently been discovered near Reshun in the Mastuj valley of Chitral State, West Pakistan. It is believed to be the fourth recorded Paleozoic laterite in the world. The laterite is entirely within a thick carbonate of the Shogram Formation of Upper Devonian (Frasnian) age. A chemical analysis of the laterite shows the principal constitutents to be: Al 2 O 3 35.5%, SiO 2 , 21.7% Fe 2 O 3 16.0%, FeO 10.3%, TiO 2 , 3.5% CaO 0.97%, and MgO 0.70%. Minerals determined by X-ray analysis include hematite, boehmite, diaspore, anatase, rutile, kaolinite, pyrophyllite and what is probably chamosite.

Chitral↗

USGS1968

Silurian-devonian reef complex near Nowshera, West Pakistan

The first Paleozoic reef belt on the Indo-Pakistan subcontinent has recently been recognized near the town of Nowshera (lat 34°00′ N., long 72°00′ E.) in northern West Pakistan. It consists of nine separate hills aligned in a 15-mile-long, east-west band rising out of the Peshawar alluvial plain. Each hill is composed of one or more reef cores whose thicknesses range from less than 100 feet to more than 700 feet. The reef cores are separated by relatively unfossiliferous carbonate rocks thinner than the reefs. The reef belt contains a fauna entirely new to Pakistan that has been dated as Early Devonian to to Late Silurian (Ludlovian to Gedinnian). The reef carbonates are the first sediments of possible Silurian age found anywhere in the country and the southernmost Devonian deposits in West Pakistan. Individual reef cores consist of faunal zones or layers that indicate a gradual growth of the reef mass from relatively quiet water upward into rough water. The presence of these reefs and correlative fossiliferous carbonate sediments in the Peshawar area suggests that in Silurian and Devonian times much of northern West Pakistan was covered by warm, shallow seas bordered by reefs or containing reef platforms. The association of these Paleozoic reefs with extensive deposits of fetid black limestones and porous dolomites may indicate economic potential for the accumulation of oil.

Town of Nowshera in northern West Pakistan↗