Rubidium-strontium dating of ore deposits hosted by Rb-rich rocks, using calcite and other common Sr-bearing minerals

Journal Article · Tue May 01 00:00:00 EDT 1984 · Geology; (United States)

DOI:https://doi.org/10.1130/0091-7613(1984)12<259:RDOODH>2.0.CO;2· OSTI ID:7061586

Ruiz, J; Jones, L M; Kelly, W C

The authors have tested a Rb-Sr technique that permits ore deposits to be dated using common gangue minerals such as calcite and fluorite. The only conditions the deposit must meet are that (1) it have minerals with a low Rb/Sr ratio and (2) it be enclosed by wall rock with a high Rb/Sr ratio. Because hydrothermal minerals acquire a strontium-isotope composition that is usually similar to that of the wall rock, minerals with low Rb/Sr ratio should record and retain the isotopic composition that the wall rock had at the time of mineralization. The difference between that ratio and that of the wall rock at present is a function of time and the Rb/Sr composition of the wall rock. The technique was tested fusing fluorite and calcite from three deposits ranging in age from Tertiary to Precambrian. In all cases the age determined here closely resembles that obtained by conventional K-Ar and Rb-Sr dating methods. The precision, however, can be poor and depends chiefly on the strontium-isotope heterogeneity of the wall rock and its Rb/Sr enrichment. 36 references, 1 figure, 1 table.

• Research Organization: Univ. of Arizona, Tucson
• OSTI ID: 7061586
• Journal Information: Geology; (United States), Vol. 12:5
• Country of Publication: United States
• Language: English

Related Subjects

58 GEOSCIENCES
CALCITE
ISOTOPE DATING
FLUORITE
ORES
GEOCHEMISTRY
RUBIDIUM ISOTOPES
STRONTIUM ISOTOPES
GANGUE
ORE COMPOSITION
AGE ESTIMATION
ALKALI METAL ISOTOPES
ALKALINE EARTH ISOTOPES
ALKALINE EARTH METAL COMPOUNDS
CALCIUM CARBONATES
CALCIUM COMPOUNDS
CALCIUM FLUORIDES
CALCIUM HALIDES
CARBON COMPOUNDS
CARBONATE MINERALS
CARBONATES
CHEMISTRY
FLUORIDES
FLUORINE COMPOUNDS
HALIDE MINERALS
HALIDES
HALOGEN COMPOUNDS
ISOTOPES
MINERALS
OXYGEN COMPOUNDS
RESIDUES
580100* - Geology &amp; Hydrology- (-1989)