Geology of the Avakutakh iron formation, Labrador
Includes bibliographical references. Includes illustrations and maps. The Avakutakh iron formation, the basal unit of the Aphebian-aged Falls Brook Group, is exposed in the Snyder Bay - Avakutakh River area of Labrador. Together with the metasedimentary Snyder Group, it forms part of the contact aur...
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Northern Illinois University
1981
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ftnorthillinuni:oai:commons.lib.niu.edu:10843/19058 2023-05-15T17:22:18+02:00 Geology of the Avakutakh iron formation, Labrador Schuh, Mary Louise Berg, Jonathan H. Department of Geology 1981 viii, 169 pages, 23 unnumbered pages application/pdf https://commons.lib.niu.edu/handle/10843/19058 eng eng Northern Illinois University https://commons.lib.niu.edu/handle/10843/19058 NIU theses are protected by copyright. They may be viewed from Huskie Commons for any purpose, but reproduction or distribution in any format is prohibited without the written permission of the authors. Geology--Newfoundland--Labrador Text Dissertation/Thesis 1981 ftnorthillinuni 2020-09-22T09:43:40Z Includes bibliographical references. Includes illustrations and maps. The Avakutakh iron formation, the basal unit of the Aphebian-aged Falls Brook Group, is exposed in the Snyder Bay - Avakutakh River area of Labrador. Together with the metasedimentary Snyder Group, it forms part of the contact aureole of the Kiglapait intrusion. Thin section study, oxygen isotope analysis, and microprobe analysis were used to determine the petrography, mineral chemistry, and metamorphic history of the Avakutakh iron formation. The Avakutakh iron formation is comprised of three metamorphic zones: grunerite-zone, hypersthene zone, and pigeonite zone. During the metamorphic event, temperatures ranged from 625 - 860°C over a distance of 565 m and pressure was essentially constant at 2.2 kbar. Anomalously low temperatures were obtained from oxygen isotope 18 analysis and appear to be the result of diffusion of ¹⁸O between quartz and magnetite with cooling. Chemical diffusion between the Avakutakh iron formation and adjacent mafic orthogranulites is limited to a band several centimeters wide. Thus, it can be assumed that the Avakutakh iron formation behaved as a closed system with respect to major non-volatile components. M.S. (Master of Science) Thesis Newfoundland Northern Illinois University (NIU): Huskie Commons Repository Newfoundland Snyder ENVELOPE(-121.386,-121.386,56.917,56.917) Falls Brook ENVELOPE(-56.865,-56.865,49.633,49.633) |
institution |
Open Polar |
collection |
Northern Illinois University (NIU): Huskie Commons Repository |
op_collection_id |
ftnorthillinuni |
language |
English |
topic |
Geology--Newfoundland--Labrador |
spellingShingle |
Geology--Newfoundland--Labrador Schuh, Mary Louise Geology of the Avakutakh iron formation, Labrador |
topic_facet |
Geology--Newfoundland--Labrador |
description |
Includes bibliographical references. Includes illustrations and maps. The Avakutakh iron formation, the basal unit of the Aphebian-aged Falls Brook Group, is exposed in the Snyder Bay - Avakutakh River area of Labrador. Together with the metasedimentary Snyder Group, it forms part of the contact aureole of the Kiglapait intrusion. Thin section study, oxygen isotope analysis, and microprobe analysis were used to determine the petrography, mineral chemistry, and metamorphic history of the Avakutakh iron formation. The Avakutakh iron formation is comprised of three metamorphic zones: grunerite-zone, hypersthene zone, and pigeonite zone. During the metamorphic event, temperatures ranged from 625 - 860°C over a distance of 565 m and pressure was essentially constant at 2.2 kbar. Anomalously low temperatures were obtained from oxygen isotope 18 analysis and appear to be the result of diffusion of ¹⁸O between quartz and magnetite with cooling. Chemical diffusion between the Avakutakh iron formation and adjacent mafic orthogranulites is limited to a band several centimeters wide. Thus, it can be assumed that the Avakutakh iron formation behaved as a closed system with respect to major non-volatile components. M.S. (Master of Science) |
author2 |
Berg, Jonathan H. Department of Geology |
format |
Thesis |
author |
Schuh, Mary Louise |
author_facet |
Schuh, Mary Louise |
author_sort |
Schuh, Mary Louise |
title |
Geology of the Avakutakh iron formation, Labrador |
title_short |
Geology of the Avakutakh iron formation, Labrador |
title_full |
Geology of the Avakutakh iron formation, Labrador |
title_fullStr |
Geology of the Avakutakh iron formation, Labrador |
title_full_unstemmed |
Geology of the Avakutakh iron formation, Labrador |
title_sort |
geology of the avakutakh iron formation, labrador |
publisher |
Northern Illinois University |
publishDate |
1981 |
url |
https://commons.lib.niu.edu/handle/10843/19058 |
long_lat |
ENVELOPE(-121.386,-121.386,56.917,56.917) ENVELOPE(-56.865,-56.865,49.633,49.633) |
geographic |
Newfoundland Snyder Falls Brook |
geographic_facet |
Newfoundland Snyder Falls Brook |
genre |
Newfoundland |
genre_facet |
Newfoundland |
op_relation |
https://commons.lib.niu.edu/handle/10843/19058 |
op_rights |
NIU theses are protected by copyright. They may be viewed from Huskie Commons for any purpose, but reproduction or distribution in any format is prohibited without the written permission of the authors. |
_version_ |
1766108868191977472 |