Nickel-cobalt-iron-copper sulfides and arsenides in solution-collapse breccia pipes, northwestern Arizona
Abstract
An extensive suite of Ni-Co-Fe-Cu sulfides and arsenides lies within the matrix of solution-collapse breccias buried deep within the plateaus of the Grand Canyon region. Ceilings over large caverns in the Redwall collapsed, brecciating the overlying sandstone and forming cylindrical breccia pipes up to 300 ft in diameter that extend vertically as much as 3,000 ft. These highly permeable breccias served as a host for the precipitation of a suite of over 100 minerals, including uraninite, sphalerite, galena and various copper phases, in addition to the Ni-Co-bearing-phase discussed here. Intricately zoned crystals of small (<1 mm), euhedral Ni-Co-Fe-As-S minerals were the first to form during the second major episode of mineralization in these pipes. Several of these phases replace minerals, such as barite and anhydrite, from the first episode. Extensive microprobe work has been done on samples from two breccia pipe mines, the Hack 2 and Orphan, which are about 50 miles apart. Mineral compositions are similar except that no copper is found in the Ni-Co-Fe phases from the Hack 2 mine, while pyrites containing 1 wt % Cu are common from the Orphan, which was mined for copper. In some of these pyrites', Cu is dominant and the mineralmore »
- Authors:
-
- Geological Survey, Denver, CO (United States)
- Sandia National Labs., Albuquerque, NM (United States)
- Publication Date:
- OSTI Identifier:
- 5023999
- Report Number(s):
- CONF-9305259-
Journal ID: ISSN 0016-7592; CODEN: GAAPBC
- DOE Contract Number:
- AC04-76DP00789
- Resource Type:
- Conference
- Journal Name:
- Geological Society of America, Abstracts with Programs; (United States)
- Additional Journal Information:
- Journal Volume: 25:5; Conference: 89. annual meeting of the Cordilleran Section and the 46th annual meeting of the Rocky Mountain Section of the Geological Society of America (GSA), Reno, NV (United States), 19-21 May 1993; Journal ID: ISSN 0016-7592
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 58 GEOSCIENCES; ARIZONA; GEOLOGIC DEPOSITS; GEOCHEMISTRY; GEOLOGY; ORIGIN; ORES; ARSENIDES; BARITE; COBALT SULFIDES; COPPER SULFIDES; CRYSTALLIZATION; CRYSTALLOGRAPHY; GALENA; IRON; MINERALOGY; NICKEL SULFIDES; PYRITE; SPHALERITE; URANINITES; ARSENIC COMPOUNDS; CHALCOGENIDES; CHEMISTRY; COBALT COMPOUNDS; COPPER COMPOUNDS; DEVELOPED COUNTRIES; ELEMENTS; MATERIALS; METALS; MINERALS; NICKEL COMPOUNDS; NORTH AMERICA; OXIDE MINERALS; PHASE TRANSFORMATIONS; PNICTIDES; RADIOACTIVE MATERIALS; RADIOACTIVE MINERALS; SULFATE MINERALS; SULFIDE MINERALS; SULFIDES; SULFUR COMPOUNDS; TRANSITION ELEMENT COMPOUNDS; TRANSITION ELEMENTS; URANIUM MINERALS; USA; 580000* - Geosciences
Citation Formats
Wenrich, K J, and Hlava, P F. Nickel-cobalt-iron-copper sulfides and arsenides in solution-collapse breccia pipes, northwestern Arizona. United States: N. p., 1993.
Web.
Wenrich, K J, & Hlava, P F. Nickel-cobalt-iron-copper sulfides and arsenides in solution-collapse breccia pipes, northwestern Arizona. United States.
Wenrich, K J, and Hlava, P F. 1993.
"Nickel-cobalt-iron-copper sulfides and arsenides in solution-collapse breccia pipes, northwestern Arizona". United States.
@article{osti_5023999,
title = {Nickel-cobalt-iron-copper sulfides and arsenides in solution-collapse breccia pipes, northwestern Arizona},
author = {Wenrich, K J and Hlava, P F},
abstractNote = {An extensive suite of Ni-Co-Fe-Cu sulfides and arsenides lies within the matrix of solution-collapse breccias buried deep within the plateaus of the Grand Canyon region. Ceilings over large caverns in the Redwall collapsed, brecciating the overlying sandstone and forming cylindrical breccia pipes up to 300 ft in diameter that extend vertically as much as 3,000 ft. These highly permeable breccias served as a host for the precipitation of a suite of over 100 minerals, including uraninite, sphalerite, galena and various copper phases, in addition to the Ni-Co-bearing-phase discussed here. Intricately zoned crystals of small (<1 mm), euhedral Ni-Co-Fe-As-S minerals were the first to form during the second major episode of mineralization in these pipes. Several of these phases replace minerals, such as barite and anhydrite, from the first episode. Extensive microprobe work has been done on samples from two breccia pipe mines, the Hack 2 and Orphan, which are about 50 miles apart. Mineral compositions are similar except that no copper is found in the Ni-Co-Fe phases from the Hack 2 mine, while pyrites containing 1 wt % Cu are common from the Orphan, which was mined for copper. In some of these pyrites', Cu is dominant and the mineral is actually villamaninite. Pyrites from both mines characteristically contain 0.5 to 3 wt % As. Metal contents in zones pyrite-bravoite-vaesite (M[sub 1]S[sub 2]) crystals at the Hack 2 mine range from Fe[sub 1] to Fe[sub .12], Ni[sub 0] to Ni[sub .86], and Co[sub 0] to Co[sub .10]. The metal content for polydymite-siegenite-violarite averages about (Ni[sub 2.33]Co[sub .39]Fe[sub .23])(S[sub 3.9]As[sub .1]). Orphan mine pyrite-bravoite-vaesite-villamaninite ranges in composition from pure FeS[sub 2] to (Ni[sub .6]Fe[sub .21]Co[sub .17])S[sub 2], and (Cu[sub .46]Ni[sub .27]Fe[sub .21]Co[sub .13])S[sub 2]. Of all the sulfides or arsenides found in these breccia pipes, only nickeline consistently occurs as the pure end member.},
doi = {},
url = {https://www.osti.gov/biblio/5023999},
journal = {Geological Society of America, Abstracts with Programs; (United States)},
issn = {0016-7592},
number = ,
volume = 25:5,
place = {United States},
year = {Thu Apr 01 00:00:00 EST 1993},
month = {Thu Apr 01 00:00:00 EST 1993}
}