Canadian Journal of Earth Sciences最新文献_第2页

Líl’wat Oral Traditions of Qw̓elqw̓elústen (Mount Meager): Indigenous Records of Volcanic Eruption, Outburst Flood, and Landscape Change in Southwest British Columbia Qw̓elqw̓elústen（Mount Meager）的 Líl'wat 口头传说：不列颠哥伦比亚省西南部火山爆发、爆发洪水和地貌变化的原住民记录

Canadian Journal of Earth Sciences Pub Date : 2024-02-15 DOI: 10.1139/cjes-2023-0098

Michael Clayton Wilson, Bill Angelbeck, Johnny Jones

{"title":"Líl’wat Oral Traditions of Qw̓elqw̓elústen (Mount Meager): Indigenous Records of Volcanic Eruption, Outburst Flood, and Landscape Change in Southwest British Columbia","authors":"Michael Clayton Wilson, Bill Angelbeck, Johnny Jones","doi":"10.1139/cjes-2023-0098","DOIUrl":"https://doi.org/10.1139/cjes-2023-0098","url":null,"abstract":"Indigenous oral traditions of the Líl̓wat Nation recount observations of Qw̓elqw̓elústen (Mount Meager), a Garibaldi Volcanic Belt volcano in southwestern British Columbia, Canada; and associated eruptive activity, mass-wasting, and outburst flooding. We present Líl̓wat observations relating to Qw̓elqw̓elústen’s ~2360 cal yr BP eruption and its aftermath, a devastating outburst flood down the Lillooet valley. The Copper Canoe story correlates with the event-sequence of pyroclastic damming of the Lillooet River and an outburst flood traveling far downstream, interrupting salmon runs and displacing people. Other stories suggest an eruptive plume and fumaroles. Recounted valley-floor changes, with proximal scouring and downstream filling of marshes allowing human resettlement, closely parallel and augment geological evidence, showing that oral traditions are equally important in holding landscape history. Oral traditions portray dramatic landscape changes, some by the Transformers, said to have traveled this land making imperfect things right. Geologically documented debris-flow delta progradation and infill of the upper 50 km of Lillooet Lake since ~12,000 cal BP underscore the land’s dynamism and the need for both sources to inform planning for future eruptive, mass-wasting, and flooding events. Traditional landscape knowledge, like Western science, is observational and evidence-based, though interpretations can differ given Indigenous belief in a sentient landscape, capable of acting with intention. Binding of stories to geographical locations has functioned as a mnemonic device to preserve orally transmitted information across many generations.","PeriodicalId":503418,"journal":{"name":"Canadian Journal of Earth Sciences","volume":"103 2","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139776721","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Líl’wat Oral Traditions of Qw̓elqw̓elústen (Mount Meager): Indigenous Records of Volcanic Eruption, Outburst Flood, and Landscape Change in Southwest British Columbia Qw̓elqw̓elústen（Mount Meager）的 Líl'wat 口头传说：不列颠哥伦比亚省西南部火山爆发、爆发洪水和地貌变化的原住民记录

Canadian Journal of Earth Sciences Pub Date : 2024-02-15 DOI: 10.1139/cjes-2023-0098

Michael Clayton Wilson, Bill Angelbeck, Johnny Jones

{"title":"Líl’wat Oral Traditions of Qw̓elqw̓elústen (Mount Meager): Indigenous Records of Volcanic Eruption, Outburst Flood, and Landscape Change in Southwest British Columbia","authors":"Michael Clayton Wilson, Bill Angelbeck, Johnny Jones","doi":"10.1139/cjes-2023-0098","DOIUrl":"https://doi.org/10.1139/cjes-2023-0098","url":null,"abstract":"Indigenous oral traditions of the Líl̓wat Nation recount observations of Qw̓elqw̓elústen (Mount Meager), a Garibaldi Volcanic Belt volcano in southwestern British Columbia, Canada; and associated eruptive activity, mass-wasting, and outburst flooding. We present Líl̓wat observations relating to Qw̓elqw̓elústen’s ~2360 cal yr BP eruption and its aftermath, a devastating outburst flood down the Lillooet valley. The Copper Canoe story correlates with the event-sequence of pyroclastic damming of the Lillooet River and an outburst flood traveling far downstream, interrupting salmon runs and displacing people. Other stories suggest an eruptive plume and fumaroles. Recounted valley-floor changes, with proximal scouring and downstream filling of marshes allowing human resettlement, closely parallel and augment geological evidence, showing that oral traditions are equally important in holding landscape history. Oral traditions portray dramatic landscape changes, some by the Transformers, said to have traveled this land making imperfect things right. Geologically documented debris-flow delta progradation and infill of the upper 50 km of Lillooet Lake since ~12,000 cal BP underscore the land’s dynamism and the need for both sources to inform planning for future eruptive, mass-wasting, and flooding events. Traditional landscape knowledge, like Western science, is observational and evidence-based, though interpretations can differ given Indigenous belief in a sentient landscape, capable of acting with intention. Binding of stories to geographical locations has functioned as a mnemonic device to preserve orally transmitted information across many generations.","PeriodicalId":503418,"journal":{"name":"Canadian Journal of Earth Sciences","volume":"48 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139836368","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Laurentide Ice Sheet configuration in southern Ontario, Canada during the last glaciation (MIS 4 to 2) from stratigraphic drilling and LIDAR-based surficial mapping 根据地层钻探和基于激光雷达的地表测绘，加拿大安大略省南部劳伦特德冰原在末次冰川时期（MIS 4 至 2）的构造

Canadian Journal of Earth Sciences Pub Date : 2024-02-15 DOI: 10.1139/cjes-2023-0091

Syed Bukhari, N. Eyles, Riley P.M. Mulligan, Abigail K. Burt, C. Eyles, R. Paulen, M. Ross, Nico Putkinen

{"title":"Laurentide Ice Sheet configuration in southern Ontario, Canada during the last glaciation (MIS 4 to 2) from stratigraphic drilling and LIDAR-based surficial mapping","authors":"Syed Bukhari, N. Eyles, Riley P.M. Mulligan, Abigail K. Burt, C. Eyles, R. Paulen, M. Ross, Nico Putkinen","doi":"10.1139/cjes-2023-0091","DOIUrl":"https://doi.org/10.1139/cjes-2023-0091","url":null,"abstract":"Regional subsurface mapping of glacial depositional systems preserved in buried bedrock paleovalleys, and quantitative analysis of new LiDAR imagery of surface glacial landforms using machine learning techniques, when combined, are powerful tools for assessing the dynamics of the Laurentide Ice Sheet (LIS) during the last (Wisconsinan) glaciation in southern Ontario. While age dating of deposits preserved below Last Glacial Maximum tills (LGM: MIS 2 < c.24,000 years before present; ybp) is still sparse, newly available sedimentological data derived by cored drilling, combined with legacy outcrop data, identifies thick (100 m +) successions of glaciolacustrine sediments and a lack of till(s) indicating that the ice sheet margin did not extend beyond the Niagara Escarpment at the western end of Lake Ontario, during the earliest phases of the glaciation (MIS 4) or the ensuing mid-Wisconsinan (MIS 3). Ice was able to extend into New York State blocking the Rome outlet to the Hudson Valley ponding deep proglacial lakes in the glacio-isostatically depressed Huron-Ontario-Erie basins recorded by thick glaciolacustrine sediments in paleovalleys. These were cannibalized by an expanding Late Wisconsinan ice sheet after ~ 24,000 ybp recorded by extensive till sheets resting on a marked erosional unconformity, with drumlinized surfaces. Analysis and visualization of LiDAR data identifies discrete statistically validated flow sets of highly elongated streamlined bedforms (mega-scale glacial lineations; MSGLs). These provide key evidence of a major reorganization of the ice sheet margin during deglaciation into lobate paleo ice streams shortly after 17,400 ybp.","PeriodicalId":503418,"journal":{"name":"Canadian Journal of Earth Sciences","volume":"19 10","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139774237","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Laurentide Ice Sheet configuration in southern Ontario, Canada during the last glaciation (MIS 4 to 2) from stratigraphic drilling and LIDAR-based surficial mapping 根据地层钻探和基于激光雷达的地表测绘，加拿大安大略省南部劳伦特德冰原在末次冰川时期（MIS 4 至 2）的构造

Canadian Journal of Earth Sciences Pub Date : 2024-02-15 DOI: 10.1139/cjes-2023-0091

Syed Bukhari, N. Eyles, Riley P.M. Mulligan, Abigail K. Burt, C. Eyles, R. Paulen, M. Ross, Nico Putkinen

{"title":"Laurentide Ice Sheet configuration in southern Ontario, Canada during the last glaciation (MIS 4 to 2) from stratigraphic drilling and LIDAR-based surficial mapping","authors":"Syed Bukhari, N. Eyles, Riley P.M. Mulligan, Abigail K. Burt, C. Eyles, R. Paulen, M. Ross, Nico Putkinen","doi":"10.1139/cjes-2023-0091","DOIUrl":"https://doi.org/10.1139/cjes-2023-0091","url":null,"abstract":"Regional subsurface mapping of glacial depositional systems preserved in buried bedrock paleovalleys, and quantitative analysis of new LiDAR imagery of surface glacial landforms using machine learning techniques, when combined, are powerful tools for assessing the dynamics of the Laurentide Ice Sheet (LIS) during the last (Wisconsinan) glaciation in southern Ontario. While age dating of deposits preserved below Last Glacial Maximum tills (LGM: MIS 2 < c.24,000 years before present; ybp) is still sparse, newly available sedimentological data derived by cored drilling, combined with legacy outcrop data, identifies thick (100 m +) successions of glaciolacustrine sediments and a lack of till(s) indicating that the ice sheet margin did not extend beyond the Niagara Escarpment at the western end of Lake Ontario, during the earliest phases of the glaciation (MIS 4) or the ensuing mid-Wisconsinan (MIS 3). Ice was able to extend into New York State blocking the Rome outlet to the Hudson Valley ponding deep proglacial lakes in the glacio-isostatically depressed Huron-Ontario-Erie basins recorded by thick glaciolacustrine sediments in paleovalleys. These were cannibalized by an expanding Late Wisconsinan ice sheet after ~ 24,000 ybp recorded by extensive till sheets resting on a marked erosional unconformity, with drumlinized surfaces. Analysis and visualization of LiDAR data identifies discrete statistically validated flow sets of highly elongated streamlined bedforms (mega-scale glacial lineations; MSGLs). These provide key evidence of a major reorganization of the ice sheet margin during deglaciation into lobate paleo ice streams shortly after 17,400 ybp.","PeriodicalId":503418,"journal":{"name":"Canadian Journal of Earth Sciences","volume":"540 ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139833923","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

The Texas Creek landslide, southwestern British Columbia: new ages and implications for the culture history and geomorphology of the mid-Fraser River region 不列颠哥伦比亚省西南部的德克萨斯溪滑坡：新的年龄及其对弗雷泽河中游地区文化史和地貌学的影响

Canadian Journal of Earth Sciences Pub Date : 2024-02-14 DOI: 10.1139/cjes-2023-0049

P. Friele, A. Blais-Stevens, John C. Gosse

{"title":"The Texas Creek landslide, southwestern British Columbia: new ages and implications for the culture history and geomorphology of the mid-Fraser River region","authors":"P. Friele, A. Blais-Stevens, John C. Gosse","doi":"10.1139/cjes-2023-0049","DOIUrl":"https://doi.org/10.1139/cjes-2023-0049","url":null,"abstract":"The Texas Creek rock avalanche is a prehistoric deposit in the Fraser River Canyon, 17 km south of Lillooet, southwestern British Columbia, Canada. Original mapping suggested that the debris consisted of two landslides: a 45 Mm3 event deposited after the Mazama tephra but before about 2 ka ago, and a 7.2 Mm3 event about 1.1 ka ago. The proposed timing of the younger landslide was correlated with a decline in the First Nations population and was proposed as an agent of cultural collapse driven by its impact on salmon returns vital to the population's sustenance. We provide six surface exposure ages using 10Be from boulder tops, with three samples from each surface that were originally posited to be older and younger debris. The six samples yielded similar ages suggesting the landslide deposit represents a single event with an average age of 2.28 ± 0.19 (2σ external error) ka before 1950 AD. Evidently, the landslide played no role in the cultural collapse. Fraser River Holocene incision rates, estimated pre- and post-landslide are between 13 and 24 mm/yr, consistent with previous estimates for the mid-Fraser River region. Landslide timing is coincident with the explosive eruption of Mount Meager, 120 km to the northwest, and with a possible landslide at Mystery Creek 85 km to the west and 65 km south of Mount Meager. The landslide may have been seismically triggered, but attribution is speculative.","PeriodicalId":503418,"journal":{"name":"Canadian Journal of Earth Sciences","volume":"158 ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139839393","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

The Texas Creek landslide, southwestern British Columbia: new ages and implications for the culture history and geomorphology of the mid-Fraser River region 不列颠哥伦比亚省西南部的德克萨斯溪滑坡：新的年龄及其对弗雷泽河中游地区文化史和地貌学的影响

Canadian Journal of Earth Sciences Pub Date : 2024-02-14 DOI: 10.1139/cjes-2023-0049

P. Friele, A. Blais-Stevens, John C. Gosse

{"title":"The Texas Creek landslide, southwestern British Columbia: new ages and implications for the culture history and geomorphology of the mid-Fraser River region","authors":"P. Friele, A. Blais-Stevens, John C. Gosse","doi":"10.1139/cjes-2023-0049","DOIUrl":"https://doi.org/10.1139/cjes-2023-0049","url":null,"abstract":"The Texas Creek rock avalanche is a prehistoric deposit in the Fraser River Canyon, 17 km south of Lillooet, southwestern British Columbia, Canada. Original mapping suggested that the debris consisted of two landslides: a 45 Mm3 event deposited after the Mazama tephra but before about 2 ka ago, and a 7.2 Mm3 event about 1.1 ka ago. The proposed timing of the younger landslide was correlated with a decline in the First Nations population and was proposed as an agent of cultural collapse driven by its impact on salmon returns vital to the population's sustenance. We provide six surface exposure ages using 10Be from boulder tops, with three samples from each surface that were originally posited to be older and younger debris. The six samples yielded similar ages suggesting the landslide deposit represents a single event with an average age of 2.28 ± 0.19 (2σ external error) ka before 1950 AD. Evidently, the landslide played no role in the cultural collapse. Fraser River Holocene incision rates, estimated pre- and post-landslide are between 13 and 24 mm/yr, consistent with previous estimates for the mid-Fraser River region. Landslide timing is coincident with the explosive eruption of Mount Meager, 120 km to the northwest, and with a possible landslide at Mystery Creek 85 km to the west and 65 km south of Mount Meager. The landslide may have been seismically triggered, but attribution is speculative.","PeriodicalId":503418,"journal":{"name":"Canadian Journal of Earth Sciences","volume":"25 3","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139779518","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Ordovician conodont biostratigraphy of northwestern Baffin Island, Nunavut, Canada, with new insights into the age and diachronism of the Ship Point Formation in the Foxe Basin 加拿大努纳武特巴芬岛西北部奥陶纪锥齿类生物地层学，对福克斯盆地船角地层的年龄和异时性的新认识

Canadian Journal of Earth Sciences Pub Date : 2024-02-14 DOI: 10.1139/cjes-2023-0101

Shunxin Zhang

{"title":"Ordovician conodont biostratigraphy of northwestern Baffin Island, Nunavut, Canada, with new insights into the age and diachronism of the Ship Point Formation in the Foxe Basin","authors":"Shunxin Zhang","doi":"10.1139/cjes-2023-0101","DOIUrl":"https://doi.org/10.1139/cjes-2023-0101","url":null,"abstract":"Northwestern Baffin Island, Nunavut, Canada, preserves the stratigraphic record in the northern margin of the Foxe Basin. The Ordovician succession exposed on an unnamed peninsula west of Steensby Inlet, northwestern Baffin Island includes the Lower and Middle Ordovician Ship Point Formation and Upper Ordovician Frobisher Bay and Amadjuak formations. Nearly 7000 conodont specimens recovered from six sections on this peninsula allow the establishment of seven conodont zones throughout this succession: Rossodus manitouensis Taxon-range Zone, Acodus deltatus–Oneotodus costatus Assemblage Zone, Oepikodus communis Interval Zone, and Cooperignathus aranda–Jumudontus gananda Assemblage Zone in units 2 and 3 of the Ship Point Formation, correlative to the upper Tremadocian and Floian, Lower Ordovician; Phragmodus polonicus Taxon-range Zone confined to unit 4 of the Ship Point Formation, correlative to the middle Darriwilian, Middle Ordovician; and Appalachignathus delicatuluss– Belodina confluens and Belodina confluens–Periodon grandis Assemblage zones limited to the Frobisher Bay and Amadjuak formations, respectively, correlative to the lower Katian, Upper Ordovician. The establishment of these conodont zones proves that (1) the Ship Point Formation in the Foxe Basin is not a continuous stratigraphic unit but has a stratigraphic interval missing that is assignable to the Dapingian and lower Darriwilian, Middle Ordovician; (2) the base of the Ship Point Formation is diachronous in the Foxe Basin, which is correlated to the upper Tremadocian on northwestern Baffin Island but to the upper Floian on Melville Peninsula; and (3) the strata younger than lower Amadjuak Formation have been eroded in this area.","PeriodicalId":503418,"journal":{"name":"Canadian Journal of Earth Sciences","volume":"58 39","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139777747","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Ordovician conodont biostratigraphy of northwestern Baffin Island, Nunavut, Canada, with new insights into the age and diachronism of the Ship Point Formation in the Foxe Basin 加拿大努纳武特巴芬岛西北部奥陶纪锥齿类生物地层学，对福克斯盆地船角地层的年龄和异时性的新认识

Canadian Journal of Earth Sciences Pub Date : 2024-02-14 DOI: 10.1139/cjes-2023-0101

Shunxin Zhang

{"title":"Ordovician conodont biostratigraphy of northwestern Baffin Island, Nunavut, Canada, with new insights into the age and diachronism of the Ship Point Formation in the Foxe Basin","authors":"Shunxin Zhang","doi":"10.1139/cjes-2023-0101","DOIUrl":"https://doi.org/10.1139/cjes-2023-0101","url":null,"abstract":"Northwestern Baffin Island, Nunavut, Canada, preserves the stratigraphic record in the northern margin of the Foxe Basin. The Ordovician succession exposed on an unnamed peninsula west of Steensby Inlet, northwestern Baffin Island includes the Lower and Middle Ordovician Ship Point Formation and Upper Ordovician Frobisher Bay and Amadjuak formations. Nearly 7000 conodont specimens recovered from six sections on this peninsula allow the establishment of seven conodont zones throughout this succession: Rossodus manitouensis Taxon-range Zone, Acodus deltatus–Oneotodus costatus Assemblage Zone, Oepikodus communis Interval Zone, and Cooperignathus aranda–Jumudontus gananda Assemblage Zone in units 2 and 3 of the Ship Point Formation, correlative to the upper Tremadocian and Floian, Lower Ordovician; Phragmodus polonicus Taxon-range Zone confined to unit 4 of the Ship Point Formation, correlative to the middle Darriwilian, Middle Ordovician; and Appalachignathus delicatuluss– Belodina confluens and Belodina confluens–Periodon grandis Assemblage zones limited to the Frobisher Bay and Amadjuak formations, respectively, correlative to the lower Katian, Upper Ordovician. The establishment of these conodont zones proves that (1) the Ship Point Formation in the Foxe Basin is not a continuous stratigraphic unit but has a stratigraphic interval missing that is assignable to the Dapingian and lower Darriwilian, Middle Ordovician; (2) the base of the Ship Point Formation is diachronous in the Foxe Basin, which is correlated to the upper Tremadocian on northwestern Baffin Island but to the upper Floian on Melville Peninsula; and (3) the strata younger than lower Amadjuak Formation have been eroded in this area.","PeriodicalId":503418,"journal":{"name":"Canadian Journal of Earth Sciences","volume":"170 ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139837423","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

The Influence of Fluvial and Glacial Watershed Dynamics on Holocene Sediment Accumulation in Cariboo Lake, Columbia Mountains, British Columbia, Canada 冲积和冰川流域动力学对加拿大不列颠哥伦比亚省哥伦比亚山脉卡里布湖全新世沉积物堆积的影响

Canadian Journal of Earth Sciences Pub Date : 2024-01-09 DOI: 10.1139/cjes-2023-0094

Alex Cebulski, J. Desloges

{"title":"The Influence of Fluvial and Glacial Watershed Dynamics on Holocene Sediment Accumulation in Cariboo Lake, Columbia Mountains, British Columbia, Canada","authors":"Alex Cebulski, J. Desloges","doi":"10.1139/cjes-2023-0094","DOIUrl":"https://doi.org/10.1139/cjes-2023-0094","url":null,"abstract":"Records of sedimentation collected from Cariboo Lake, situated in the northern Columbia Mountains, British Columbia, Canada, are analyzed to assess Holocene fluvial and glacial watershed dynamics. The aim of this study is to provide a proxy record of Holocene hydroclimate and glacier change from sediment archives at a higher temporal resolution compared to available records for the Interior Ranges of British Columbia. Deglacial and Holocene sediment accumulation is observed to reach a maximum thickness of 35 m in deep parts of the lake, using sub-bottom acoustic soundings. A transition from massive to well-stratified sediments is observed in the sub-bottom acoustic record during final phases of valley deglaciation in the region (~10.5–9 cal ka BP). Laminae couplets are interpreted to be deposited annually according to two 14C dates and a varve counting chronology. Two long cores, 2.9 and 3.8 m in length, were selected for analysis with estimated basal dates of 2 cal ka BP. Trends in downcore sediment characteristics were linked to environmental changes in the glaciated catchment headwaters at a temporal resolution of ~100 yrs. Upstream lake filtering of river floodplains and lakes prevented finding a higher temporal resolution linkage between the sediment characteristics and headwater fluvial and glacial activity. Despite some upstream filtering, the Cariboo River was found to be the primary source of sediment to the long core sites. Observed grain size and varve thickness from two long cores show above average trends which are coincident with cooler temperatures and the primary glacier advances over the last 2 ka.","PeriodicalId":503418,"journal":{"name":"Canadian Journal of Earth Sciences","volume":"47 21","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139442580","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Net evolution of subglacial sediment transport in the Quebec-Labrador sector of the Laurentide Ice Sheet 劳伦泰德冰原魁北克-拉布拉多地区冰川下沉积物迁移的净演变

Canadian Journal of Earth Sciences Pub Date : 2024-01-05 DOI: 10.1139/cjes-2023-0050

J. Rice, M. Ross, H. Campbell, R. Paulen, M. McClenaghan

{"title":"Net evolution of subglacial sediment transport in the Quebec-Labrador sector of the Laurentide Ice Sheet","authors":"J. Rice, M. Ross, H. Campbell, R. Paulen, M. McClenaghan","doi":"10.1139/cjes-2023-0050","DOIUrl":"https://doi.org/10.1139/cjes-2023-0050","url":null,"abstract":"The Laurentide Ice Sheet's (LIS) interior had a dynamic polythermal base, but the spatiotemporal variations of subglacial processes related to ice-divide migration and other transient changes remain largely unknown, limiting our understanding of regional glacial dynamics. Previous studies focused on the regional glacial landform record, while ice sheet models lacked detailed parameterization within these regions, leading to an overestimation of cold-based subglacial conditions' extent and duration. In this study, glacial sediment dispersal patterns as identified by heavy minerals, clasts, and multivariate statistics of till matrix geochemistry were used to assess ice-sheet dynamics within the Quebec-Labrador sector of the LIS. The earliest ice-flow phase produced and transported till across the study area (> 175 km). However, major oxide data from till matrix geochemistry shows a correlation with underlying bedrock and this relationship is relatively common in areas of thin till cover and resistant bedrock lithologies. These results suggest a switch from an early phase of widespread erosion and long, sustained sediment transport to one of more limited erosion, perhaps abrasion dominant, and shorter transport. Till compositional data and related dispersal patterns add supporting evidence to earlier ice sheet reconstructions based on ice-flow indicators and 10Be data together suggesting a transition from widespread uniform warm-based conditions during the earliest ice-flow followed by the development of an ice divide, its migration, and more sporadic warm-based conditions. Consequently, a thorough understanding of ice-flow history is essential for ice sheet modelling and future mineral exploration programs in inner ice sheet regions of the LIS.","PeriodicalId":503418,"journal":{"name":"Canadian Journal of Earth Sciences","volume":"54 18","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139382169","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

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