Metacolloid pyrite-pitchblende veinlets of high-grade hydrothermal ores at the Dalmatovskoe uranium deposit, Transural Region, Russia: New data on the mineralogy, geochemistry, age, and uranium sources

2014 ◽  
Vol 52 (5) ◽  
pp. 372-387
Author(s):  
Yu. M. Dymkov ◽  
A. S. Saltykov ◽  
G. A. Kolpakov ◽  
D. I. Krinov ◽  
A. P. Aleshin ◽  
...  
Keyword(s):  
Uranium Deposit ◽  
High Grade ◽  
Transural Region ◽  
Uranium Sources

Neotectonic stage in the formation of the Khokhlovskoe uranium deposit, eastern Transural region: Structural, hydrochemical, mineralogical, and geochemical formation conditions

2013 ◽  
Vol 55 (6) ◽  
pp. 411-437 ◽  
Author(s):  
S. F. Vinokurov ◽  
V. Yu. Prokof’ev ◽  
V. I. Malkovsky ◽  
Yu. M. Dymkov ◽  
A. V. Chugaev ◽  
...  
Keyword(s):  
Uranium Deposit ◽  
Transural Region ◽  
Formation Conditions

Mineralogy and U/Pb, Pb/Pb, and Sm/Nd geochronology of the Key Lake uranium deposit, Athabasca Basin, Saskatchewan, Canada

1992 ◽  
Vol 29 (5) ◽  
pp. 879-895 ◽  
Author(s):  
C. Carl ◽  
E. von Pechmann ◽  
A. Höhndorf ◽  
G. Ruhrmann
Keyword(s):  
Uranium Deposit ◽  
Time Span ◽  
Radiometric Dating ◽  
Age Difference ◽  
High Grade ◽  
Uranium Deposits ◽  
Isotopic Data ◽  
Athabasca Basin ◽  
The Past ◽  
Preparation Techniques

The Key Lake deposit is one of several large, high-grade, unconformity-related uranium deposits located at the eastern margin of the Athabasca Basin in northern Saskatchewan, Canada. The deposit consists of the Gaertner orebody, now mined out, and the Deilmann orebody, which is presently being mined. In the past, radiometric dating efforts yielded an age of oldest ore-forming event of 1250 ± 34 Ma at the Gaertner orebody and 1350 ± 4 Ma at the Deilmann orebody. This unlikely age difference called for further investigation. Innovative preparation techniques were used to separate the paragenetically oldest U mineral, an anisotropic uraninite. Ore microscopy and U/Pb isotopic data show that the oldest event of uranium emplacement occurred simultaneously at the two orebodies, at 1421 ± 49 Ma. The primary ore-forming phase was followed by younger generations of U mineralization and periods of remobilization. Sm/Nd data of Key Lake uraninite form an isochron corresponding to an age of 1215 Ma. This is interpreted as the age of a uranium remobilization or a new mineralizing event. The lead found in the Athabasca Group above the Deilmann deposit and in galena appears to be a mixture of a common lead and radiogenic lead mobilized from the orebody over a time span of at least 1000 Ma.

Geometallurgical ore characterization of the high-grade polymetallic unconformity-related uranium deposit

2021 ◽  
Vol 59 (5) ◽  
pp. 813-845
Author(s):  
Andrew J. Kaczowka ◽  
T. Kurt Kyser ◽  
Tom G. Kotzer ◽  
Matthew I. Leybourne ◽  
Daniel Layton-Matthews
Keyword(s):  
Uranium Deposit ◽  
Mineral Chemistry ◽  
Molar Ratio ◽  
High Grade ◽  
Tectonic Structures ◽  
Athabasca Basin ◽  
Significant Control ◽  
Mine Effluent ◽  
Ore Characterization

ABSTRACT Cigar Lake is a polymetallic, unconformity-related uranium deposit with complex geochemistry and mineralogy located in the eastern Athabasca Basin of northern Saskatchewan, Canada. Variable concentrations and spatial distributions of elements of concern, such as As, Mo, Ni, Co, Se, and Zr, associated with the high-grade tetravalent uranium ores [UO2+x; U(SiO4)1–x(OH)4x] present unique mining, metallurgical, and environmental challenges. Sulfide and arsenide minerals have significant control over As, Mo, Ni, Co, and Se abundances and have properties that affect element of concern mobility, thus requiring consideration during mineral processing, mine-effluent water treatment, and long-term tailings management. The U-bearing (uraninite, coffinite) and metallic arsenide (nickeline, often called “niccolite” in the past), sulfarsenide (gersdorffite, cobaltite), and sulfide (chalcopyrite, pyrite, galena, bornite, chalcocite, sphalerite, pyrrhotite) minerals provide the main controls on the distributions of the elements of concern. Arsenic, Ni, and Co occur primarily in a reduced state as 1:1 molar ratio, Ni-Co:As, arsenide, and sulfarsenide minerals such as gersdorffite, nickeline, and cobaltite. Molybdenum occurs within molybdenite and uraninite. Selenium occurs within coffinite, sulfide, and sulfarsenide minerals. Zirconium is found within detrital zircon and coffinite. The spatial distribution and paragenesis of U-, As-, and S-bearing minerals are a result of the elemental composition, pH, and redox conditions of early formational and later meteoric fluids that formed and have modified the deposit through access along lithostratigraphic permeability and tectonic structures. Using the holistic geometallurgical paradigm presented here, the geochemistry and mineral chemistry at Cigar Lake can be used to optimize and reduce risk during long-term mine and mill planning.

1278: The Role of Diagnostic Criteria of Obstruction in Patients with High Grade Cystocele: Correlation to Subjective Symptoms

2007 ◽  
Vol 177 (4S) ◽  
pp. 421-421
Author(s):  
Veronica Triaca ◽  
Christian O. Twiss ◽  
Ramdev Konijeti ◽  
Larissa V. Rodriguez ◽  
Shlomo Raz
Keyword(s):  
Diagnostic Criteria ◽  
High Grade ◽  
Subjective Symptoms
Sign in / Sign up

Export Citation Format

Share Document