Poison Canyon Mine, Poison Canyon area, Ambrosia Lake subdistrict, McKinley County, New Mexico, USAi

Regional Level Types
Poison Canyon Mine	Mine
Poison Canyon area	Area
Ambrosia Lake subdistrict	Mining Sub-district
McKinley County	County
New Mexico	State
USA	Country

Structure: Poison Canyon Fault The Poison Canyon Fault And A Series Of Smaller Faults And Fractures.

Tectonics: Chaco Slope

Deposit: The ore deposits of this district are chiefly filled fissure veins with or without some replacement of the wallrock. They are usually single fissures ranging in width from 2 ft. To 8 ft. And are filled with banded and crustified vein material. Vein systems trending north-south are valuable for gold and silver with copper occurring sparingly in places. Vein systems trending east-west or roughly radial trends are valuable chiefly for silver and copper. In the extreme southern end of the district are veins containing galena, sphalerite and some associated gold, silver and chalcopyrite. Crib sites and record numbers for this district are alaska group(d002800) ; info.src : 1 pub lit the deposit consists of two tabular, stringlike deposits associated with fossil logs and organic debris. There isboth trend and redistributed ore present.

Development: The poison canyon mine was the first sandstone uranium discovery in the grants district. A navajo sheepherder, paddy martinez, was drawn to this site thinking that radiation in the canyon might be responsible for the mysterious deaths ofhundreds of sheep. Assays of the uraniferous ore showed appreciable quantities of selenium. Several years later helen cannon of the USGS geobotanical branch proposed that the deaths were due to the consumption of the noxious plant, astragalus, which grows selectively in the presence of selenium.

Geology: In this district the oldest rocks exposed are limestones, shaley sandstones and shales of the penn. Magdalena group which are overlain by red sandstones and conglomerates of the perm. Abo fm.. Outcrops of these sedimentary rocks appear along the lower portions of some fault blocks and in general the beds dip to the east. Tert. To late cret. Propylitic andesites are more characteristic of the region and form extensive flows, tuffs and breccias along the eastern portion of the black range. Rhyolite flows and tuffs overlie the andesites but are less extensive. Tectonic setting is continental platform disrupted by extensive cenozoic vulcanism and basin and range deformation. The deposit occurs in the poison canyon sandstone of the brushy basin member of the morrison formation.

Rock formation(s): Morrison


Ore(s): A Series Of Faults And Fractures

Other Databases

Link to USGS MRDS:	10072196

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References