URANIUM IN THE PHILLIPS MINE-CAMP SMITH AREA, PUTNAM AND WESTCHESTER COUNTIES, NEW YORK

Technical Report · Tue Jan 01 04:00:00 EST 1957

OSTI ID:4298526

Klemic, H; Eric, J H; McNitt, J R; McKeown, F A

Uraniferous rock was discovered in the Phillips mineCamp Smith area in 1953. Precambrian rocks of the Hudson Highlands of the New England physiographic province underlie the area. Hornblende pegmatite intrudes hornblende gneiss and diorite. The hornblende pegmatite and dmorite are conformable with regional structures in the gneiss. Cross-cutting bodies of oligoclase-quartz pegmatite intrude the diorite and hornblende gneiss. Uraninite occurs in hornblende pegmatite and in adjacent hornblende gneiss and diorite in an elongate zone that is mineralized with magnetite and iron sulfides. The mineralized zone strikes northeast and dips steeply northwest. The Phillips pyrrhotite-pyrite ore body at the northeast end of this zone plunges northeast. The uraninlte is in crystals and grains, most of which range from a millimeter to a centimeter in diameter. Subhedral uraninite crystallized from the pegmatite magma. The isotopic age of a crystal of uraninite from the hornblende pegmatite is about 920 million years. Magnetite is believed to have been emplaced during the latest stages of the consolidation of the hornblende pegmatite and is associated with secondary augite resulting from the alteration, possibly pneumatolytic, of hornblende in the pegmatite and adjacent rocks. The solutions that deposited magnetite and altered hornblende to augite embayed and rounded some of the uraninite crystals. lron sulfides are believed to have been deposited by hydrothermal solutions that followed the main channels through which the hornblende pegmatite magma and the magnetite solutions had been introduced. Later, oligoclase-quartz pegmatite intruded the area discordantly. The lead-alpha age of zircon from the oligoclase- quartz pegmatite is about 620 million years. Results of exploration suggest that the deposits are submarginal under 1955 marketing conditions for uranium. (auth)

• Research Organization: Geological Survey, Washington, D.C.
• NSA Number: NSA-13-000704
• OSTI ID: 4298526
• Report Number(s): TEI-530
• Country of Publication: United States
• Language: English

Related Subjects

AGE ESTIMATION
ALUMINUM SILICATES
AUGITE
CALCIUM SILICATES
CRYSTALS
DECOMPOSITION
DEPOSITS
DIORITES
ECONOMICS
GEOLOGY
GEOLOGY AND MINERALOGY
GNEISS
HIGH TEMPERATURE
HORNBLENDE
HYDROLOGY
HYDROTHERMAL STAGE
INTRUSION
IRON ORES
IRON OXIDES
IRON SULFIDES
LEAD ISOTOPES
LEAD METHOD
MAGMA
MAGNESIUM SILICATES
MAGNETITE
NEW YORK
OLIGOCLASE
PEGMATITES
PROSPECTING
PYRITE
PYROXENES
PYRRHOTITE
QUARTZ
ROCKS
SOLUTIONS
STRATIGRAPHY
URANINITES
URANIUM ORES
ZIRCON
ZIRCONIUM SILICATES