| Title | Ichnology and paleoenvironmental interpretations of the Cretaceous-Paleocene rift succession of northeast Baffin Island region, Nunavut, Canada |
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| Author | Dafoe, L ;
Haggart, J; Williams, G; Stimson, M |
| Source | AAPG - Annual Convention and Exhibition, abstracts; American Association of Petroleum Geologists, Annual Meeting Abstracts 2019, 2019 p. 1-2 |
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| Year | 2019 |
| Alt Series | Natural Resources Canada, Contribution Series 20180428 |
| Publisher | American Association of Petroleum Geologists |
| Meeting | AAPG - Annual Convention and Exhibition; San Antonio; US; May 19-22, 2019 |
| Document | serial |
| Lang. | English |
| Media | paper; digital |
| File format | pdf (Adobe® Reader®) |
| Province | Nunavut |
| NTS | 38A; 38B; 38C; 38D; 48D |
| Area | Baffin Island; Pond Inlet; Bylot Island |
| Lat/Long WENS | -81.0000 -72.0000 74.0000 72.5000 |
| Subjects | paleontology; sedimentology; stratigraphy; tectonics; Science and Technology; Paleogene; Paleocene; ichnology; ichnofossils; ichnofacies; trace fossils; palynology; paleoenvironment; tectonic setting;
tectonic history; rifting; sea floor spreading; depositional history; depositional environment; sedimentary structures; sedimentation rates; bedrock geology; lithology; sedimentary rocks; clastics; mudstones; sandstones; Eclipse Trough; North Bylot
Trough; Scoyenia; Ophiomorpha; Cruziana; Phycosiphon; Macaronichnus; Dinoflagellates; Phanerozoic; Cenozoic; Tertiary; Mesozoic; Cretaceous |
| Program | GEM2: Geo-mapping for Energy and Minerals Baffin Mapping of onshore Cretaceous Strats |
| Released | 2019 06 30 |
| Abstract | Clastic strata cropping out along northeast Baffin Island, Canada, preserve an onshore stratigraphic record of rifting that formed the adjacent Baffin Bay region, beginning in the Early Cretaceous with
seafloor spreading ceasing near the end of the Eocene. Cretaceous through Paleocene strata of this succession are preserved in the area around Pond Inlet, in Eclipse Trough along southwest Bylot Island, and in North Bylot Trough on north Bylot
Island. Analysis of the ichnology and sedimentology of 35 stratigraphic sections of these strata was undertaken, in conjunction with palynological study, to better understand their evolving depositional environments and to provide an analogue for the
associated offshore section in Baffin Bay. Lower Cretaceous syn-rift strata of Eclipse Trough include primarily fluvial facies. However, a unique interval containing wave ripples and mud-crack casts, as well as surface trails, trackways, resting
traces, shallow dwellings, and microbial-induced sedimentary structures reflecting the Scoyenia Ichnofacies, is interpreted as lake-margin in origin. In another synrift section, Ophiomorpha characterize middle shoreface strata, and wave-rippled to
hummocky cross-stratified beds contain a diverse, but opportunistic, archetypal Cruziana Ichnofacies within storm-dominated lower shoreface deposits. Overlying Upper Cretaceous transgressive mudstones reflect more distal marine deposition and are
dominated by Phycosiphon. Shallower, proximal outer-shelf settings with distal Cruziana Ichnofacies assemblages are also seen in the mudstones where they transition to sandstones. These sandstones consist of progradational, storm-dominated, inner
shelf through foreshore deposits, with alternating stratified and bioturbated beds containing either archetypal Cruziana Ichnofacies or Macaronichnus-dominated suites. Overlying Paleocene sandstones generally show evidence of high sedimentation rates
suggesting deltaic deposition. Paleocene mudstones are rarely bioturbated, primarily by diminutive, marine, grazing traces. Palynological analysis indicates a lack of dinocysts in these rocks, supporting a brackish estuarine or prodeltaic setting.
Seafloor sampling from Baffin Bay reveals similar facies to those seen onshore, demonstrating that the onshore record provides a vital analogue for understanding the adjacent offshore succession. These analyses help to document depositional
complexities within an evolving rift system. |
| Summary | (Plain Language Summary, not published)
The Cretaceous and Paleogene onshore stratigraphy of Bylot Island, Nunavut provides a vital analogue for understanding the adjacent offshore succession
in Baffin Bay where sampling is very limited. Detailed analysis of the sedimentology and trace fossils of 35 stratigraphic sections provides new insights into the depositional paleoenvironments of the rock units. Specifically, the overall succession
shows a predominance of marine deposition and storm-dominance with similar depositional paleoenvironments seen between the two structurally isolated areas of Bylot Island. |
| GEOSCAN ID | 314519 |
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