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Geology topics

J. D. Friedman

Publications and source records attributed to J. D. Friedman.

6 recordsLinked to original sources
USGS1994

Possible Mesozoic age of Ellenville Zn-Pb-Cu(Ag) deposit, Shawangunk Mountains, New York

Ore textures, epithermal open-space filling of Permian structures of the Alleghanian orogeny, and largely postorogenic mineralization of the Ellenville, New York, composite Zn-Pb-Cu(Ag) vein system, provide permissive evidence for post-Permian mineralization. Isochron ages determined by 40Ar/39Ar laser-fusion techniques for K-bearing liquid inclusions in main-stage quartz from the Ellenville deposit additionally suggest a Mesozoic time of mineralization, associated with extensional formation of the Newark basin. The best 40Ar/39Ar total-fusion age range is 165 ?? 30 to 193 ?? 35 Ma. The Mesozoic 40Ar/39Ar age agrees with that of many other dated northern Appalachian Zn-Pb-Cu(Ag) deposits with near-matching lead isotope ratios, and adds new evidence of Jurassic tectonism and mineralization as an overprint to Late Paleozoic tectonism at least as far north as Ellenville (lat. 41??43???N). ?? 1994 Springer-Verlag.

Mineralium Deposita↗
USGS1970

Aerial infrared surveys of Reykjanes and Torfajökull thermal areas, Iceland, with a section on cost of exploration surveys

In 1966 and 1968 aerial infrared surveys were conducted over 10 of 13 high-temperature thermal areas in Iceland. The surveys were made with an airborne scanner system, utilizing radiation in the 4.5–5.5 μm wavelength band. Supplementary ground geological studies were made in the Reykjanes and Torfajökull thermal areas to interpret features depicted on the infrared imagery and to relate zones of high heat flux to tectonic structure. In the Reykjanes area in southwestern Iceland a shallow ground temperature map was prepared for temperatures at a depth of 0.5 meters; comparison of this map with the infrared imagery reveals some striking similarities. It appears that aerial infrared surveys outline the surface thermal patterns of high-temperature areas and aid in relating these patterns to possible geological structures controlling the upflow of hot water. Amplitude-slicing techniques applied to the magnetically taped airborne scanner data permit an estimate to be made of the natural heat output on the basis of size of area and specific radiance. In addition to their value in preliminary studies of high-temperature areas, infrared surveys conducted at regular intervals over thermal area under exploitation can provide valuable data on changes that occur in surface manifestations with time. e.

Reykjanes, Torfajokull↗
USGS1970

Satellite observation of effusive volcanism

Infrared emission from an active effusive volcanic eruption on Surtsey, Vestmannaeyjar, Iceland, was recorded by airborne and satellite infrared systems at irregular intervals between 19 August and 3 October 1966. Ground and lava temperature measurements and volumetric lava outflow data permitted a comparison to be made between total thermal-energy yield and radiant emission recorded by the satellite system. The Nimbus HRIR recorded radiant emission at a level of about 3% of the estimated total thermal yield.

British Interplanetary Society Journal↗