Title | Descriptions of drill cores and thin sections from lower Paleozoic strata, southeastern Baffin Island shelf, Nunavut |
Download | Downloads |
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Licence | Please note the adoption of the Open Government Licence - Canada
supersedes any previous licences. |
Author | Bingham-Koslowski, N |
Source | Geological Survey of Canada, Open File 8409, 2018, 75 pages, https://doi.org/10.4095/308354 Open Access |
Links | Erratum
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Year | 2018 |
Publisher | Natural Resources Canada |
Document | open file |
Lang. | English |
Media | on-line; digital |
File format | pdf; docx |
Province | Nunavut; Northern offshore region |
NTS | 15L/11; 15L/12; 15L/13; 15L/14; 15M/03; 15M/04; 15M/05; 15M/06; 15M/11; 15M/12 |
Area | Baffin Island; Davis Strait; Baffin-Labrador Seaway |
Lat/Long WENS | -64.0000 -63.0000 63.7500 62.5000 |
Subjects | marine geology; sedimentology; paleontology; continental margins; continental shelf; drill core analyses; core descriptions; thin section microscopy; bedrock geology; lithology; sedimentary rocks;
limestones; dolomites; metamorphic rocks; gneisses; igneous rocks; intrusive rocks; granites; fossils; sedimentary environment; depositional environment; depositional history; dolomitization; diagenesis; bioturbation; Upper Ordovician; Middle
Ordovician; Baffin Island Shelf; Iapetus Ocean; Phanerozoic; Paleozoic; Ordovician |
Illustrations | location maps; tables; photographs; stratigraphic charts; photomicrographs |
Program | GEM2: Geo-mapping for Energy and Minerals Baffin Region Atlas |
Released | 2018 06 26; 2018 07 27 |
Abstract | Drill cores from the southeastern Baffin Island shelf offer rare insights into the lower Paleozoic bedrock geology that underlies the northern Baffin-Labrador Seaway Mesozoic to Cenozoic rift
stratigraphy. Six seabed drill cores (Cruise 75-009 Phase V, Stations 4, 5, 8A, 8B and Cruise 77027, Stations 026A, and 028) were recovered from offshore Baffin Island by the Geological Survey of Canada during marine cruises in the 1970s. The
lithology (sedimentology and paleontology) of the drill cores and their associated thin sections is analyzed to provide information on the depositional environments that existed in the Iapetus Ocean during the Middle to Upper Ordovician. The drill
cores are predominantly composed of fine, lime mud, with evidence of bioturbation observed in four of the six cores. The drill cores exhibit varying degrees of dolomitization, with the drill core from 75-009, Phase V Station 4 being the most
diagenetically altered. Disseminated pyrite is found throughout the drill cores and thin sections, and the cores from Stations 8A and 8B contain finely macerated organic matter dispersed in the matrix. Fossils identified in the drill cores and thin
sections include bivalves, trilobites, crinoids, sponge spicules, gastropods, brachiopods, corals, cephalopods, dasycladacean green algae, ostracods, bryozoans, and radiolarians, as well as possible calcispheres. Undifferentiated echinoderm and shell
fragments are also common throughout the strata. Initial interpretations based on observations from the drill cores and thin sections suggest depositional milieus ranging from shallow, photic zone environments to deeper, open marine settings.
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Summary | (Plain Language Summary, not published) This Open File provides an overview of the six Paleozoic drill cores recovered from the southeastern Baffin Island Shelf during Geological Survey of
Canada research cruises in the 1970s. The Open File report includes detailed core and thin section descriptions for the six drill cores and represents the first time such descriptions have been published. The core and thin section descriptions
highlight the lithological and paleontological nature of each drill core, providing insights into what life was like during the middle to late Ordovician along the western margin of the Iapetus Ocean. Preliminary interpretations regarding the
paleoenvironmental conditions represented by these drill cores are given, however more in-depth interpretations as well as regional connections and significance will be published in a peer-reviewed paper at a later date. |
GEOSCAN ID | 308354 |
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