Academic literature on the topic 'Laurentides region'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the lists of relevant articles, books, theses, conference reports, and other scholarly sources on the topic 'Laurentides region.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Journal articles on the topic "Laurentides region"
1
Gauthier, Robert. "La répartition et l'habitat du Tomenthypnum falcifolium au Québec–Labrador." Canadian Journal of Botany 65, no. 2 (February 1, 1987): 286–98. http://dx.doi.org/10.1139/b87-040.
Full textAbstract:
The discovery of Tomenthypnum falcifolium (Ren. ex Nich.) Tuom. in Canada is rather recent. For a long time, it was considered as a variety of Tomenthypnum nitens. Some characters allowing the distinction of the two species are discussed and illustrated. Distribution maps of both species in the Québec–Labrador Peninsula are presented. Habitat conditions of Tomenthypnum falcifolium in the Laurentides Park are derived from a study of peatland vegetation. It grows mainly in extremely poor fens, the dominant peatland type of this region. It is a hummock-preferring species and never forms extensive colonies. Its ecological amplitude is then rather different from that of Tomenthypnum nitens which is more commonly found in rich fens.
2
Desponts, Mireille, André Desrochers, Louis Bélanger, and Jean Huot. "Structure de sapinières aménagées et anciennes du massif des Laurentides (Québec) et diversité des plantes invasculaires." Canadian Journal of Forest Research 32, no. 12 (December 1, 2002): 2077–93. http://dx.doi.org/10.1139/x02-127.
Full textAbstract:
This study was undertaken to determine the contribution of old-growth and senescent forest stands regenerated through clear-cutting to the biodiversity of wet boreal fir stands in eastern Quebec because overmature stands are becoming scarce in that region. The study area was located in the Laurentian Mountains north of the city of Québec. The structure and composition of nonvascular plant communities (mosses, hepatica, lichens, and saprophytic fungi) of old-growth forests were compared with those of mature or senescent fir stands harvested 60 years ago. Nonvascular plants have a more uniform structure and a lower diversity in mature than in senescent or old-growth forests. A variety of specialized soil- and wood-inhabiting species and many rare species not observed in mature stands regenerated through clear-cutting are found in the latter. Structural diversity of senescent second-growth fir stands becomes similar to that of old-growth stand because of mortality within the overstory. These structural characteristics favour the development of diversified nonvascular plant communities, especially wood-inhabiting species found on slightly decomposed woody debris and soil-inhabiting species that colonize disturbed soils.[Journal translation]
3
Wójcik, Katarzyna. "(Re)visions télévisuelles de la colonisation du Nord – série médiatique d’Un homme et son péché de Claude-Henri Grignon." Romanica Silesiana 18, no. 2 (December 28, 2020): 86–97. http://dx.doi.org/10.31261/rs.2020.18.07.
Full textAbstract:
Claude-Henri Grignon’s novel Un homme et son péché presents the life of French Canadian colonial settlers of the Laurentides region at the end of XIXth century. It depicts a realistic image of the colonisation period of Quebec history. The novel is at the origin of a media series that englobes a radio adaptation, three filmic adaptations, theater adaptations, a comic, and two television series. The aim of this article is to discuss the vision of colonisation by analysing two television series based on Un homme et son péché: Les Belles Histoires des pays d’en haut broadcast from 1956 to 1970 and Les Pays d’en haut broadcast from 2016 to 2019 on ICI Radio-Canada Télé 1. The analysis will try to trace modifications inherent to the process of adaptation on different levels (protagonists, representation of space, ideological discourse) and their influence on the vision of the colonisation period.
4
Hébert, Rémi, Claude Samson, and Jean Huot. "Factors Influencing the Abundance of Berry Plants for Black Bears, Ursus americanus, in Quebec." Canadian Field-Naturalist 122, no. 3 (July 1, 2008): 212. http://dx.doi.org/10.22621/cfn.v122i3.601.
Full textAbstract:
Berries generally represent the primary food source used by Black Bears (Ursus americanus) during summer and sometimes fall. Our study attempted to identify factors influencing the abundance of these critical resources for Black Bears in Quebec. We used data from the ecological inventories of the Ministère de l’Environnement du Québec. Three different study areas were selected, including the Papineau-Labelle Wildlife Reserve (326 sample plots; 24 species), the Laurentides Wildlife Reserve (679 sample plots; 16 species) and the Côte-Nord administrative region (1944 sample plots; 30 species). Each site represented a different bioclimatic domain. Characteristics of the dominant vegetation (density and height), soil texture, and drainage classes (vertical or oblique) were used as analysis factors. In general, height and density of the dominant vegetation had a significant effect on the abundance of berry plants. Berry plants were more abundant in plots where dominant vegetation height and density were low. Soil texture had little effect on the abundance of berry plants, and the influence of drainage varied depending on the region. This study allowed us to determine the optimal sites of berry resources for Black Bears.
5
Brigot, Guillaume, Marc Simard, Elise Colin-Koeniguer, and Alexandre Boulch. "Retrieval of Forest Vertical Structure from PolInSAR Data by Machine Learning Using LIDAR-Derived Features." Remote Sensing 11, no. 4 (February 13, 2019): 381. http://dx.doi.org/10.3390/rs11040381.
Full textAbstract:
This paper presents a machine learning based method to predict the forest structure parameters from L-band polarimetric and interferometric synthetic aperture radar (PolInSAR) data acquired by the airborne UAVSAR system over the Réserve Faunique des Laurentides in Québec, Canada. The main objective of this paper is to show that relevant parameters of the PolInSAR coherence region can be used to invert forest structure indicators computed from the airborne LIDAR sensor Laser Vegetation and Ice Sensor (LVIS). The method relies on the shape of the observed generalized PolInSAR coherence region that is related to the three-dimensional structure of the scene. In addition to parameters describing the coherence shape, we consider the impact of acquisition parameters such as the interferometric baseline, ground elevation and local surface slope. We use the parameters as input a multilayer perceptron model to infer canopy features as estimated from LIDAR waveform. The output features are canopy height, cover and vertical profile class. Canopy height and canopy cover are estimated with a normalized RMSE of 13%, 15% respectively. The vertical profile was divided into 3 distinct classes with 66% accuracy.
6
Gagnier, Marianne, Isabelle Laurion, and Anthony J. DeNicola. "Control and Surveillance Operations to Prevent Chronic Wasting Disease Establishment in Free-Ranging White-Tailed Deer in Québec, Canada." Animals 10, no. 2 (February 12, 2020): 283. http://dx.doi.org/10.3390/ani10020283.
Full textAbstract:
Chronic wasting disease (CWD), a degenerative and fatal prion disease affecting cervids, was detected for the first time in the province of Québec, Canada, in a red deer (Cervus elaphus) farm in the Laurentides region on 10 September 2018. To assess CWD prevalence and control the disease in the free-ranging white-tailed deer (Odocoileus virginianus) population, a response plan including enhanced surveillance, population control, regulatory measures, and public outreach was deployed by the Ministry of Forests, Wildlife, and Parks (MFFP). In the 401 km2 white-tailed deer control area, a total of 750 free-ranging white-tailed deer were culled over 70 days, from 22 September to 15 December 2018. Of the culled deer, 534 were tested for CWD. We also tested for CWD a total of 447 white-tailed deer hunted from the enhanced surveillance zone and 2584 free-ranging white-tailed deer harvested outside this zone. Regulations were applied to prevent the spread of the disease through movements of infected animals harvested by hunters. Although no case of CWD was detected in free-ranging cervids in Québec in 2018, this does not confirm the absence of the disease in these populations. However, the results suggest that if CWD is present, few free-ranging cervids are infected, making it possible to prevent its establishment in the province of Québec.
7
Patenaude, Marc, Paul Baudron, Laurence Labelle, and Janie Masse-Dufresne. "Evaluating Bank-Filtration Occurrence in the Province of Quebec (Canada) with a GIS Approach." Water 12, no. 3 (March 1, 2020): 662. http://dx.doi.org/10.3390/w12030662.
Full textAbstract:
Due to the abundance of surface water in the province of Quebec, Canada, it is suspected that many groundwater wells are pumping a mixture of groundwater and surface water via induced bank filtration (IBF). The regulatory framework in Quebec provides comprehensive guidelines for the development and monitoring of surface water and groundwater drinking water production systems. However, the regulations do not specifically address hybrid groundwater-surface water production systems such as IBF sites. More knowledge on the use of IBF in the province is needed to adjust the regulations with respect to the particularities of these systems. In order to provide a first evaluation of municipal wells potentially using IBF and the corresponding population served by these wells, a Geographic Information Science framework (GISc) was used to implement an IBF spatial database and calculate the distance from each well to the nearest surface water body. GISc is based on open source GIS programs and openly available data, to facilitate the reproducibility of the work. From this provincial scale approach, we show that nearly one million people are supplied by groundwater from municipal wells located <500 m from a surface water body, and half a million have a significant probability to be supplied by IBF wells. A more focused look at the watershed scale distribution of wells allows us to improve our interpretations by considering the aquifer type and other regional factors. This approach reveals strong spatial variability in the distribution of wells in proximity to surface water. Of the three selected regions, one has a high potential for IBF (Laurentides), one requires additional information do draw precise conclusions (Nicolet), and the third region (Vaudreuil-Soulanges) is unlikely to have widespread use of IBF. With this study, we demonstrate that extensive use of IBF is likely and that there is a need for improved understanding and management of these sites in order to properly protect the drinking water supply.
8
Bell, M., and E. P. Laine. "Erosion of the Laurentide Region of North America by Glacial and Glaciofluvial Processes." Quaternary Research 23, no. 2 (March 1985): 154–74. http://dx.doi.org/10.1016/0033-5894(85)90026-2.
Full textAbstract:
Collection of seismic reflection data from continental margins and ocean basins surrounding North America makes it possible to estimate the amount of material eroded from the area formerly covered by Laurentide ice sheets since major glaciation began in North America. A minimum estimate is made of 1.62 × 106 km3, or an average 120 m of rock physically eroded from the Laurentide region. This figure is an order of magnitude higher than earlier estimates based on the volume of glacial drift, Cenozoic marine sediments, and modern sediment loads of rivers. Most of the sediment produced during Laurentide glaciation has already been transported to the oceans. The importance of continental glaciation as a geomorphic agency in North America may have to be reevaluated. Evidence from sedimentation rates in ocean basins surrounding Greenland and Antarctica suggests that sediment production, sediment transport, and possibly denudation by permanent ice caps may be substantially lower than by periodic ice caps, such as the Laurentide. Low rates of sediment survival from the time of the Permo-Carboniferous and Precambrian glaciations suggest that predominance of marine deposition during some glacial epochs results in shorter lived sediment because of preferential tectonism and cycling of oceanic crust versus continental crust.
9
Bobrowsky, Peter, and Nathaniel W. Rutter. "The Quaternary Geologic History of the Canadian Rocky Mountains." Géographie physique et Quaternaire 46, no. 1 (November 23, 2007): 5–50. http://dx.doi.org/10.7202/032887ar.
Full textAbstract:
ABSTRACT The Canadian Rocky Mountains figured prominently during the glacial history of western Canada. First as a western limit or boundary to the Laurentide Ice Sheet, second as an eastern margin of the Cordilleran Ice Sheet, and finally as a centre of local Montane ice. Throughout the Quaternary, complex interactions of glacier ice from these three ice sources markedly changed the physical form of the Rocky Mountains, Trench and Foothills areas. Investigations into the Quaternary history of this region have been ongoing since the beginning of the last century. Since about 1950, the number of studies performed in this area have increased significantly. This paper briefly reviews the historical accomplishments of Quaternary work in the region up to the period of about 1950. From this time to the present, individual study efforts are examined in detail according to the three geographic regions: 1) the northern Rocky Mountains (from the Liard Plateau south to the McGregor Plateau), 2) the central Rocky Mountains (from the McGregor Plateau south to the Porcupine Hills) and 3) the southern Rocky Mountains (from the Porcupine Hills south to the international border). In the northern region, geologic data suggest a maximum of two Rocky Mountain glaciations and only one Laurentide glaciation and no ice coalescence. In the central region, three of four Rocky Mountain events, and at least two Laurentide events are known. Only in the central region is there good evidence for ice coalescence, but the timing of this event is not clearly established. In the south, at least three Rocky Mountain episodes and a variable number of Laurentide episodes are recognized. There is no evidence for ice coalescence. A number of facts support the proposal that Cordilleran ice crossed the Continental Divide and joined with local Montane ice at several locations. However, this expansion of western ice occurred before the Late Wisconsinan in all areas but Jasper. In general, the chronological data presented suggest that the Late Wisconsinan glaciation in the Rocky Mountains was a short-lived event which started around or after 20 ka years ago and ended before 12 ka ago.
10
Wolfe, Stephen A., David J. Huntley, and Jeff Ollerhead. "Relict Late Wisconsinan Dune Fields of the Northern Great Plains, Canada*." Paleoenvironments 58, no. 2-3 (July 18, 2006): 323–36. http://dx.doi.org/10.7202/013146ar.
Full textAbstract:
Abstract Late Wisconsinan dune activity is investigated within the present-day boreal forest and parkland regions of the northern Great Plains, Canada, to extend the understanding of the spatial and temporal eolian record. Optical ages from stabilized sand dunes document the timing of past activity. Eolian activity ranges from about 16 ka in west-central Alberta to 9 ka in northwestern Saskatchewan. Between about 16 and 13 ka, dune activity in central Alberta occurred in an ice-proximal tundra setting along the margins of the Laurentide and Cordilleran ice sheets. Predominant dune-forming winds were from the west and northwest. Dune activity continued in this area between about 13 and 11 ka within parkland and grassland settings as the Laurentide Ice Sheet retreated to the northeast. Winds continued to blow from the west and northwest, and the climate was likely influenced by an increasingly dominant Pacific air mass. Also beginning at about 13 ka, dune-forming winds along the margins of the retreating Laurentide Ice Sheet were influenced by anticyclonic winds from the southeast that were maintained until about 9 ka. As the Laurentide Ice Sheet retreated, these southeasterly anticyclonic winds were successively replaced by winds from the northwest associated with the Pacific air mass. Dune activity across the region terminated in a time-transgressive manner from the southwest, at about 11 ka, to the northeast, at about 9 ka, with the establishment of boreal forest vegetation and reduced wind strength.
Dissertations / Theses on the topic "Laurentides region"
1
Lanthier, Gabriel. "Variations inter journalières dans la structure des communautés de poissons : implications pour le développement de modèles de qualité d'habitats." Thèse, 2009. http://hdl.handle.net/1866/8126.
Full text
2
Rainville, Rosalie. "La résilience par le terroir : une sociologie du bien-vivre dans les Hautes-Laurentides." Thèse, 2016. http://hdl.handle.net/1866/18847.
Full textAbstract:
Cette étude sociologique porte sur la Municipalité régionale de comté (MRC) Antoine-Labelle dans la région des Hautes-Laurentides au Québec. Historiquement, depuis le début des années 1900, la forêt a constitué la principale assise économique et sociale de la MRC. Depuis 2005, « la crise forestière » frappe durement cette région québécoise. Un mouvement de la transition s’est installé au sein de la communauté régionale. À l’intersection de la nature et de la culture, le terroir se présente depuis lors comme l’une des voies privilégiées de la résilience. À travers le terroir, c’est le « vivre de » et le « bien vivre ensemble » que les habitants cherchent à repenser dans leur région. Aujourd’hui, plusieurs initiatives mettant en valeur le terroir régional, notamment des projets d’agriculture biologique, sont repérables à l’ensemble du territoire des Hautes-Laurentides. Plus qu’une simple ouverture économique, le terroir est porteur de nouveaux récits sociaux et symboliques dans la région. Dans ce mémoire de maîtrise, notre objectif est précisément de mettre en lumière les représentations sociales du terroir de certains acteurs du domaine agroalimentaire de la MRC Antoine-Labelle. Nous cherchons à comprendre comment le terroir se construit, se pense, se vit et se raconte dans cette région. En interrogeant dix-sept acteurs, notamment des agriculteurs, des artisans du domaine alimentaire, des chefs, des restaurateurs et des représentants de la gouvernance régionale, ceux-ci montrent que ce concept est porteur de valeurs sociales et environnementales qui répondent à de nouvelles aspirations au sein de la communauté. Non sans difficultés, le terroir renvoie pour les acteurs interrogés à des valeurs d’autonomie, de qualité de vie, de convivialité, de conscience écologique, d’éducation et d’espoir pour la relève à venir. Cette étude sociologique du terroir dans les Hautes-Laurentides jette finalement un éclairage nouveau sur le bien-vivre en région rurale au Québec.This sociological study is about the Regional County Municipality (RCM) of Antoine-Labelle in the Hautes-Laurentides region of Quebec. Since the early 1900s, the forest has been the main economic and social base of the MRC. Since 2005, "the forestry crisis" has heavily affected this region of Quebec. A transition movement has emerged within the regional community. At the intersection of nature and culture, the terroir has appeared as one of the preferred pathways toward resilience. Through the terroir, it’s the ideas of "living" and "living together" that inhabitants are sinking to rethink in their region. Today, several initiatives which highlight the regional terroir, including organic farming projects, have emerged throughout the territory of the Hautes-Laurentides. More than just an economic opportunity, the terroir brings with it new social and symbolic narratives in the region. In this master thesis, our goal is precisely to highlight the social representations of the terroir of some actors in this field of activity in the Antoine-Labelle RCM. We seek to understand how the terroir is constructed, conceptualized, lived and told in this region. By interviewing seventeen actors, including farmers, artisans, chefs and representatives of regional governance, we show that this concept carries social and environmental values that express new aspirations within the community. For the actors interviewed and not without its challenges, the terroir refers to values such as autonomy, quality of life, friendliness, environmental awareness, education and hope for the next generation. This sociological study of the terroir in the Hautes-Laurentides sheds new light on what is meant by “living well” in rural Quebec.
3
Montpetit, Véronique. "Les stratégies visant à améliorer l’acceptabilité des voies de contournement dans les petites municipalités du Québec : le cas de quatre municipalités le long de la route 117 dans la région des Laurentides." Thèse, 2013. http://hdl.handle.net/1866/10854.
Full textAbstract:
Cette recherche explore les différentes stratégies mises en place afin de minimiser les impacts négatifs encourus à la suite de la mise en service d'une voie de contournement pour les petites municipalités du Québec. Les stratégies identifiées ont été relevées dans la littérature, dans la documentation municipale ainsi que dans des études de cas, soit par des relevés terrains et des entretiens sur le territoire de quatre (4) municipalités. Les stratégies de planification mises sur pied visent essentiellement la configuration des entrées de villes, la signalisation ainsi que les programmes de revitalisation des noyaux urbains. Il ressort de l'analyse que la bonne acceptation sociale des voies de contournement est liée à la présence de concertation entre les différentes parties prenantes d'un projet tout au long de celui-ci. De plus, le temps écoulé entre les premiers balbutiements du projet et la mise en service d'une voie de contournement doit être d'une durée acceptable afin que des stratégies planifiées concordent avec le contexte économique et culturel dans lequel s'insèrera le projet.
La recherche dresse ainsi le portrait des stratégies planifiées pour les municipalités situées le long de la route nationale 117 et ayant des voies de contournement. Plus spécifiquement, l'étude de cas porte sur les municipalités de Mont-Tremblant (secteur de Saint-Jovite), La Conception, Labelle et Rivière-Rouge dans la région des Laurentides.This research explores the different strategies currently put into place to minimize the negative effects of the implementation of bypass routes on the small cities of the province of Québec. An assessment of the different strategies used was done by reviewing literature and municipal documentation, as well as reviewing case studies by analysing field reports and maintenance reports of four (4) municipalities. The planning strategies elaborated are essentially aimed at the configuration of city entrance lanes, the utilisation of road signs and the programs of revitalisation of urban areas. The main element that can be observed is that in order to have a good social acceptation of bypass routes, there has to be a good dialogue between the different parties involved, and that for the entire duration of the road works. Also, in order for the strategies to concord with the economic and cultural realities of the municipalities, the amount of time elapsed between the beginning of the project and the actual implementation of the relief route has to be reasonable. This research overlooks the strategies planned for municipalities that are located in the Laurentides region alongside national road 117 and that are accessible via a bypass route. More specifically, this case study focuses on the cities of Mont-Tremblant (Saint-Jovite aera) , La Conception, Labelle and Rivière-Rouge.
Books on the topic "Laurentides region"
1
Histoire de la presse hebdomadaire au Québec : laurentides, Lanaudisre. Montréal, QC: Hebdos Québec, 2008.
Find full textBook chapters on the topic "Laurentides region"
1
Gibson, Roy K. "Umbria and the Laurentine Shore." In Man of High Empire, 132–61. Oxford University Press, 2020. http://dx.doi.org/10.1093/oso/9780199948192.003.0006.
Full textAbstract:
Pliny owned two important residences outside Rome: one on the Laurentine shore; the other in Umbria. Pliny calls the latter villa ‘Tuscan’: a reference to the ethnicity (rather than geography) of the locality. He was deeply embedded and widely connected in Umbria, but plays the region down, to give Comum prominence. A network of Umbrian friends can be documented, plus marriage to ‘Venuleia’: daughter of an established Umbro-Etruscan senatorial family. Pliny says little about her, to give the later marriage to Calpurnia of Comum more publicity. Pliny’s persona in Umbria is warm, and marked by an interest in religious sites. At the Laurentine villa, Pliny focuses on reading, writing, and improvement of the self. How does Pliny’s persona at his villas relate to ancient conceptions of the ‘true self’? Pliny’s leisure was based on the labour of those who worked his huge Umbrian estates. What were his record and practices as a wealthy landowner?
2
Elias, Scott A. "Paleoecology and Late Quaternary Environments of the Colorado Rockies." In Structure and Function of an Alpine Ecosystem. Oxford University Press, 2001. http://dx.doi.org/10.1093/oso/9780195117288.003.0023.
Full textAbstract:
Present-day environments cannot be completely understood without knowledge of their history since the last ice age. Paleoecological studies show that the modern ecosystems did not spring full-blown onto the Rocky Mountain region within the last few centuries. Rather, they are the product of a massive reshuffling of species that was brought about by the last ice age and indeed continues to this day. Chronologically, this chapter covers the late Quaternary Period: the last 25,000 years. During this interval, ice sheets advanced southward, covering Canada and much of the northern tier of states in the United States. Glaciers crept down from mountaintops to fill high valleys in the Rockies and Sierras. The late Quaternary interval is important because it bridges the gap between the ice-age world and modern environments and biota. It was a time of great change, in both physical environments and biological communities. The Wisconsin Glaciation is called the Pinedale Glaciation in the Rocky Mountain region (after terminal moraines near the town of Pinedale, Wyoming; see chapter 4). The Pinedale Glaciation began after the last (Sangamon) Interglaciation, perhaps 110,000 radiocarbon years before present (yr BP), and included at least two major ice advances and retreats. These glacial events took different forms in different regions. The Laurentide Ice Sheet covered much of northeastern and north-central North America, and the Cordilleran Ice Sheet covered much of northwestern North America. The two ice sheets covered more than 16 million km2 and contained one third of all the ice in the world’s glaciers during this period. The history of glaciation is not as well resolved for the Colorado Front Range region as it is for regions farther north. For instance, although a chronology of three separate ice advances has been established for the Teton Range during Pinedale times, in northern Colorado we know only that there were earlier and later Pinedale ice advances. We do not know when the earlier advance (or multiple advances) took place. However, based on geologic evidence (Madole and Shroba 1979), the early Pinedale glaciation was more extensive than the late Pinedale was.
3
Davias, Michael E., and Thomas H. S. Harris. "Postulating an unconventional location for the missing mid-Pleistocene transition impact: Repaving North America with a cavitated regolith blanket while dispatching Australasian tektites and giving Michigan a thumb." In In the Footsteps of Warren B. Hamilton: New Ideas in Earth Science. Geological Society of America, 2022. http://dx.doi.org/10.1130/2021.2553(24).
Full textAbstract:
ABSTRACT This thesis embraces and expands upon a century of research into disparate geological enigmas, offering a unifying catastrophic explanation for events occurring during the enigmatic mid-Pleistocene transition. Billions of tons of “Australasian tektites” were dispatched as distal ejecta from a target mass of continental sediments during a cosmic impact occurring ca. 788 ka. The accepted signatures of a hypervelocity impact encompass an excavated astrobleme and attendant proximal, medial, and distal ejecta distributions. Enigmatically, the distal tektites remain the only accepted evidence of this impact’s reality. A protracted 50 yr search fixated on impact sites in Southeast Asia—the location of the tektites—has failed to identify the requisite additional impact signatures. We postulate the missing astrobleme and proximal/medial ejecta signatures are instead located antipodal to Southeast Asia. A review of the gradualistic theories for the genesis and age of the “Carolina bay” landforms of North America finds those models incapable of addressing all the facts we observe. Research into 57,000 of those oriented basins informs our speculation that they represent cavitation-derived ovoid basins within energetically delivered geophysical mass surge flows emanating from a cosmic impact. Those flows are seen as repaving regions of North America under blankets of hydrated impact regolith. Our precisely measured Carolina bay orientations indicate an impact site within the Laurentide ice sheet. There, we invoke a grazing regime impact into hydrated early Mesozoic to late Paleozoic continental sediments, similar in composition to the expected Australasian tektites’ parent target. We observe that continental ice shielded the target at ca. 788 ka, a scenario understood to produce anomalous astroblemes. The ensuing excavation allowed the Saginaw glacial lobe’s distinctive and unique passage through the Marshall Sandstone cuesta, which encircles and elsewhere protects the central region of the intracratonic Michigan Basin. Subsequent erosion by multiple ice-age transgressions has obfuscated impact evidence, forming Michigan’s “Thumb” as an enduring event signature. Comprehensive suborbital modeling supports the distribution of distal ejecta to the Australasian tektite strewn field from Michigan’s Lower Peninsula. The mid-Pleistocene transition impact hypothesis unifies the Carolina bays with those tektites as products of an impact into the Saginaw Bay area of Lake Huron, USA. The hypothesis will be falsified if cosmogenic nuclide burial dating of Carolina bay subjacent stratigraphic contacts disallows a coeval regolith emplacement ca. 788 ka across North America. We offer observations, interdisciplinary insights, and informed speculations fitting for an embryonic concept involving a planetary-scale extraterrestrial impact.
4
Elias, Scott. "Millennial and Century Climate Changes in the Colorado Alpine." In Climate Variability and Ecosystem Response in Long-Term Ecological Research Sites. Oxford University Press, 2003. http://dx.doi.org/10.1093/oso/9780195150599.003.0033.
Full textAbstract:
Ecosystems are the products of regional biotic history, shaped by environmental changes that have occurred over thousands of years. Accordingly, ecological changes take place at many timescales, but perhaps none is more significant than the truly long-term scale of centuries and millennia, for it is at these timescales that ecosystems form, break apart, and reform in new configurations. This is certainly true in the alpine regions, where glaciations have dominated the landscape for perhaps 90% of the last 2.5 million years (Elias 1996a). In the alpine tundra zone, the periods between ice ages have been relatively brief (10,000–15,000 years), whereas glaciations have been long (90,000–100,000 years). Glacial ice has been the dominant force in shaping alpine landscapes. Glacial climate has been the filter through which the alpine biota has had to pass repeatedly in the Pleistocene. This chapter discusses climatic events during the last 25,000 years (figure 18.1). At the beginning of this interval, temperatures cooled throughout most of the Northern Hemisphere, culminating in the last glacial maximum (LGM), about 20,000–18,000 yr b.p. (radiocarbon years before present). The Laurentide and Cordilleran ice sheets advanced southward, covering most of Canada and the northern tier of the United States. Glaciers also crept down from mountaintops to fill high valleys in the Rocky Mountains. In the Southern Rockies, the alpine tundra zone crept downslope into what is now the subalpine, beyond the reach of the relatively small montane glaciers. By about 14,000 yr b.p., the glacier margins began to recede, leading eventually to the postglacial environments of the Holocene. It is now becoming apparent that the climate changes that drove these events were surprisingly rapid and intense. This chapter examines the evidence for these climatic changes and the biotic response to them in the alpine zone of Colorado. To reconstruct the environmental changes of this period, we must rely on proxy data, that is, the fossil record of plants and animals, combined with geologic evidence, such as the age and location of glacial moraines in mountain valleys. As of this writing, the principal biological proxy data that have been studied in the Rocky Mountains are fossil pollen and insects.
Conference papers on the topic "Laurentides region"
1
Groult, Benjamin. "FACTORS INVOLVED IN THE BIOGEOGRAPHIC DISTRIBUTION OF MICROBIAL DIVERSITY IN SUBSURFACE WATER OF THE LAURENTIDES REGION, QUEBEC." In GSA 2020 Connects Online. Geological Society of America, 2020. http://dx.doi.org/10.1130/abs/2020am-355079.
Full text
2
Naylor, Shawn, Andrew D. Wickert, Douglas A. Edmonds, and Brian J. Yanites. "THE BURIED BEDROCK SURFACE AND PLIOCENE TOPOGRAPHY OF THE NORTH AMERICAN LAURENTIDE REGION." In GSA Annual Meeting in Indianapolis, Indiana, USA - 2018. Geological Society of America, 2018. http://dx.doi.org/10.1130/abs/2018am-323073.
Full text
3
McDonald, Jennifer, Kaleb G. Wagner, and Gary N. Meyer. "CHRONOLOGY AND EXTENT OF THE LAURENTIDE ICE SHEET IN THE ARROWHEAD REGION, NORTHEASTERN MINNESOTA, USA." In 54th Annual GSA North-Central Section Meeting - 2020. Geological Society of America, 2020. http://dx.doi.org/10.1130/abs/2020nc-346971.
Full text
4
Barth, Aaron M., Shaun A. Marcott, Alex Horvath, Jeremy D. Shakun, and Joseph M. Licciardi. "EARLY DEGLACIAL THINNING OF THE LAURENTIDE ICE SHEET FOLLOWED BY RAPID REGIONAL DEGLACIATION." In GSA Annual Meeting in Seattle, Washington, USA - 2017. Geological Society of America, 2017. http://dx.doi.org/10.1130/abs/2017am-307235.
Full text
5
Robitaille, Alexis, Robert-André Daigneault, and Olivier J. Caron. "LAKES HISTORY: A KEY TO UNDERSTANDING THE DEGLACIATION PATTERN OF THE LAURENTIDE AND LANAUDIERE REGION (SOUTHERN QUEBEC)." In GSA 2020 Connects Online. Geological Society of America, 2020. http://dx.doi.org/10.1130/abs/2020am-358014.
Full text
6
Lowe, Theodor Rex Hartmann, David Malone, Jennifer Gifford, David Grimley, and Patrick Colgan. "DETRITAL ZIRCON GEOCHRONOLOGY OF ILLINOIS-EPISODE GLACIAL DEPOSITS: CONSTRAINING THE DYNAMICS OF THE PENULTIMATE LAURENTIDE GLACIATION IN THE GREAT LAKES REGION." In GSA Connects 2021 in Portland, Oregon. Geological Society of America, 2021. http://dx.doi.org/10.1130/abs/2021am-369304.
Full textReports on the topic "Laurentides region"
1
Kerr, D. E. Reconnaissance surficial geology, Bloody River, Northwest Territories-Nunavut, NTS 96-P. Natural Resources Canada/CMSS/Information Management, 2022. http://dx.doi.org/10.4095/329457.
Full textAbstract:
Preliminary surficial geology, based on airphoto interpretation and limited legacy field data of Bloody River map area, records a dynamic Late Wisconsin glacial landscape. Streamlined till and bedrock landforms, relating to Laurentide ice originating east of the map region, indicate regional westward flow diverged northwestward and southwestward at the eastern end of two topographic highs. Ice then converged between and south of these two highs, then diverged at the western end of these highlands. During deglaciation, ice stagnated in northwestern and central highland regions, forming extensive hummocky moraine, large kames, recessional moraines, and kame moraines. In other parts of the map area, hummocky till, small moraines, and undifferentiated till ridges, were deposited over fluted till. Outwash plains, eskers, and meltwater corridors record northwestward to southwestward meltwater flow. Glaciolacustrine sediments associated with glacial Lake McConnell occur in the southeast, up to 280 m elevation. Other unrelated, isolated glaciolacustrine deltas indicate small ice-marginal lakes between 400 and 460 m elevation.
2
Rice, J. M., R. C. Paulen, M. Ross, M. B. McClenaghan, and H E Campbell. Quaternary geology of the south Core Zone area, Quebec and Labrador. Natural Resources Canada/CMSS/Information Management, 2022. http://dx.doi.org/10.4095/330903.
Full textAbstract:
The complex glacial geomorphology of east-central Quebec and western Labrador has resulted in conflicting ice sheet reconstructions leaving many questions regarding the behaviour of large ice sheets within their inner regions. Specifically, the ice-flow chronology and subglacial conditions remain poorly constrained. To address this, surficial geology investigations were conducted across the border of Quebec and Labrador. A complex glacial history consisting of five ice-flow phases influenced by regional ice stream dynamics was identified, including a near-complete ice-flow reversal. During each ice-flow phase, the subglacial thermal conditions fluctuated both spatially and temporally, resulting in palimpsest glacial dispersal patterns. Deglacial ages from samples collected as part of this research confirm deglaciation occurred relatively rapidly around 8 ka. The results of this work improve our understanding of the glacial history of an inner region of the Laurentide Ice Sheet and have important implications for mineral exploration in the southern Core Zone area.
3
McMartin, I., and P. J. Henderson. A relative ice-flow chronology for the Keewatin Sector of the Laurentide Ice Sheet, Northwest Territories (Kivalliq region, Nunavut). Natural Resources Canada/ESS/Scientific and Technical Publishing Services, 1999. http://dx.doi.org/10.4095/210178.
Full text
4
Paulen, R. C., and I. R. Smith. Surficial geology, Sulphur Bay, western Great Slave Lake, Northwest Territories, NTS 85-G. Natural Resources Canada/CMSS/Information Management, 2022. http://dx.doi.org/10.4095/330073.
Full textAbstract:
The Sulphur Bay map sheet is a low-relief terrain underlain by lower- to middle-Devonian dolostone and limestone. A thin (&lt;4 m thick) Laurentide Ice Sheet-derived glacial sediment cover drapes most of the landscape, except for bedrock outcrops exposed near Great Slave Lake. Relict glacial landforms record an older northwest ice flow across the region. These are strongly overprinted by subsequent west-southwest-oriented flutings and mega-scale glacial lineations formed during deglaciation. As ice retreated, the entire map area became inundated by glacial Lake McConnell and then subsequently by the expanded postglacial Great Slave Lake. This produced a discontinuous, coarse winnowed surface lag over higher terrain and thin sheets of glaciolacustrine nearshore sands over lower-lying regions. Abundant iceberg furrows occur throughout the map area. Bogs and fens have formed over much of the landscape and display extensive thermokarst.
5
McMartin, I., J. E. Campbell, P.-M. Godbout, P. Behnia, T. Tremblay, and P. X. Normandeau. High-resolution mapping of glacial landscapes in the north-central portion of the Laurentide Ice Sheet in Nunavut and Northwest Territories. Natural Resources Canada/CMSS/Information Management, 2022. http://dx.doi.org/10.4095/330867.
Full textAbstract:
A new glacial geomorphology map covers approximately 415,000 km2 in a core region of the Laurentide Ice Sheet in Nunavut. The compilation builds on recent and legacy maps and is supplemented by visual digitization of glacigenic features using high-resolution digital elevation (ArcticDEM) and Landsat 8 images. From this unprecedented, detailed inventory of &gt;156,000 features and &gt;14,000 field observations, we identify various glacial landsystems, many of which are entirely new and others that are significantly modified or updated. These include ice streams, palimpsest ice flows, and areas where basal ice thermal regimes fluctuated between cold-based and warm-based. The GIS data comprise glacial features mapped at original and generalized scales, standardized field datasets and interpreted glacial landsystems. These comprehensive georeferenced datasets can be used to reconstruct the glacial history in the interior portion of the Laurentide Ice Sheet in Nunavut and Northwest Territories and to identify distinct glacial sediment transport paths for applications to mineral exploration.
6
Kerr, D. E. Reconnaissance surficial geology, Bebensee Lake, Northwest Territories-Nunavut, NTS 86-M. Natural Resources Canada/CMSS/Information Management, 2022. http://dx.doi.org/10.4095/329456.
Full textAbstract:
Preliminary surficial geology, based on airphoto interpretation and limited legacy field data of the Bebensee Lake map area, records a complex glacial landscape. Highly streamlined till, till blanket, hummocky till, moraine complex, and ridged till are dominant units. Glaciofluvial sand and gravel form eskers, subglacial meltwater corridors, ice-contact deposits, and outwash plains. Fine-grained glaciolacustrine sediments in the south occur predominantly in lowlands below 250 m elevation, relating to glacial Lake McConnell. Multiple lobes of Laurentide ice glaciated the area. Relict glacial landforms record older westward to west-southwestward ice flow. In the southeast, these are strongly overprinted by subsequent north-oriented flutings, decreasing in intensity northward, and originating from a lobe south of the map area. Streamlined till landforms, relating to a third lobe originating east and northeast of the map region, indicate the last ice flow was dominantly westward in east-central regions, and southwestward in the north and west. During deglaciation, widespread hummocky till was deposited, and major moraines and esker complexes formed along the margins of two ice lobes.
7
Smith, I. R., R. C. Paulen, and G W Hagedorn. Surficial geology, northeastern Cameron Hills, Northwest Territories, NTS 85-C/3, 4, 5, and 6. Natural Resources Canada/CMSS/Information Management, 2021. http://dx.doi.org/10.4095/328129.
Full textAbstract:
The northeastern Cameron Hills comprise a Cretaceous bedrock upland, rising &gt;550 m above the regional boreal plains. It was inundated by the Laurentide Ice Sheet and includes much of a prominent 60 by 20 km southwest-oriented mega-scale glacial lineation field, formed in thick till. Subsequent ice flow on northeast Cameron Hills occurred north to south, and a series of lobate and ice-thrust moraines suggest glacial surging. Rotational bedrock slumps cover the eastern and northern flanks of Cameron Hills, and extensive alluvial fan deposits draining from these slopes blanket the surrounding topography. The Cameron River formed as a glacial spillway, draining southwest across the upland before turning north and draining into Tathlina Lake. An expansive raised delta and glaciolacustrine sediment cover extending up to ~295 m above sea level, south of Tathlina Lake, records impoundment of an ice-marginal lake between the northeastward-retreating Laurentide Ice Sheet and Cameron Hills.