Oxygen- and strontium-isotopic studies of the skye intrusive complex, northwest Scotland

Thesis/Dissertation · Thu Jan 01 04:00:00 EST 1981

OSTI ID:6294914

Smith, B M

This dissertation is comprised of three parts, each of which addresses some aspect of the meteoric-hydrothermal fluid/rock interaction which affected the rocks within and near the Skye intrusive complex. Part 1 was undertaken to determine the scale and magnitude of hydrothermal Sr contamination in the Coire Uaigneich Granophyre (CUG). Sr- and O-isotopic and electron microprobe results show that Sr was mobile in the low-/sup 18/O meteoric-hydrothermal fluids, that Sr-exchange between these fluids and the CUG was limited to thin (less than or equal to 1 cm) zones of bleached and albitized granophyre adjacent to fractures, and that the scale of O-exchange was much larger. Part 2 focuses on the stable isotopic and mineralogical compositions of the Beinn an Dubhaich Granite and its Durness Limestone host rocks. Part 3 is an attempt to discriminate between magmatic and subsolidus /sup 18/O depletions in porphyritic felsitic dikes from two widely separated regions of the intrusive complex. Eastern Red Hills felsites, collected approximately 9 km from the exposed margin of the Cuillins intrusion, probably crystallized from O-isotopically normal magmas. Empirical and experimental data on the kinetics of volume diffusion of oxygen in feldspar minerals and quartz (in the presence of H/sub 2/O) suggest that the /sup 18/O depletion in quartz and feldspar from the SPF may be attributed to very high-temperature (>600/sup 0/C) subsolidus exchange with circulating low-/sup 18/O fluids.

• Research Organization: Brown Univ., Providence, RI (USA)
• OSTI ID: 6294914
• Country of Publication: United States
• Language: English

Related Subjects

58 GEOSCIENCES
580300* -- Mineralogy
Petrology
& Rock Mechanics-- (-1989)
ALKALINE EARTH ISOTOPES
CHEMICAL ANALYSIS
ELECTRON MICROPROBE ANALYSIS
EUROPE
EVEN-EVEN NUCLEI
GEOLOGIC FORMATIONS
GEOTHERMOMETRY
HYDROTHERMAL ALTERATION
IGNEOUS ROCKS
ISOTOPE RATIO
ISOTOPES
LIGHT NUCLEI
MICROANALYSIS
MINERALOGY
NUCLEI
OXYGEN 18
OXYGEN ISOTOPES
PLUTONIC ROCKS
ROCKS
STABLE ISOTOPES
STRONTIUM ISOTOPES
TEMPERATURE EFFECTS
UNITED KINGDOM
WESTERN EUROPE