A multibeam bathymetric survey of Bay of Islands, Newfoundland: new evidence of late-glacial and Holocene geological processes

Multibeam bathymetric imagery of Ray of Islands, Newfoundland, is interpreted within the context of late-glacial and post-glacial processes- West of Humber Arm, the fiord floor is irregular and deep. Humber Arm has steep sidewalls and a flat floor. It contains glaciomarine mud. capped by a layer of red mud probably derived from the Deer Lake Basin, which was connected to the ocean ca. 12.2 ka. In the early postglacial period, sediments on the fiord sidewalls slid into deep water, forming erosional channels. Depositional lobes, stacked in many areas, overlie glaciomarine sediments in deep water. The glaciomarine and submarine slide sediments are overlain by postglacial mud that is imprinted by elongate, ovoid, and circular fluid-escape trenches, and sedimentary furrows. The natural morphology of the fiord has been modified by anthropogenic activity at Comer Brook. Effects include an apron of bark offshore from the paper mill, dredge spoil, and a sunken vessel at the mouth of Humber River. Large submarine slides, probably triggered by wharf construction at Seal Head, formed deep channels on the fiord sidewalls and overlapping depositional lobes on the fiord floor. They are morphologically similar to the lateglacial slide failures in the fund. RÉSUMÉ Les images bathymétriques multifaisceaux de Bay of Islands, Terre-Neuve, sont interprétées dans le contexte des processus tardiglaciaires et post-glaciaires. À I'ouest de Humber Arm. Ie fond du l’jord est irrégulier et profond. Humber Arm est doté de parois abruptes et d'un fond plat. Il renferme de la boue glaciomarine recouverte d'une couche de boue rouge provenant probablemenl du bassin du lac Deer, qui était relié à l'océan il y a environ 12.2 millies d'années avant nos jours. Au début de la période post-glaciaire, Ies sediments sur Ies parois du l’jord ont glissé a l’intérieur de I'eau profonde en formant des chenaux d'érosion. Des lobes sédimentaires s'empilant en de nombreux endroits recouvrent les sédiments glaciomarins en eaux profondes. Les sédiments de glissement glaciomarins et sous-marins sont recouverts d'une boue post-glaciaire marquée de tranchées allongées, ovoides et circulaires d'évacuation des liquides et de silions sédimentaires. L'activité anthropique a modi fié la morphologic naturelle du l’jord a Corner Brook. Les effets de cette activité comprennent un tablier d'écorce au large de la papeterie, des matériaux de dragage et un navire ayant coulé à I'embouchure dc la riviére Humber. D'importants éboulements sous-marins, probablement causés par la construction du quai de Seal Head, ont formé des chenaux profonds dans les parois du l’jord et des lobes sédimentaires qui se superposcnt sur Ic fond du l’jord Ceux-ci sont morphologiquemcnt analogues aux fractures de glissement tardiglaciaires dans le l’jord. Traduit par la rédactio

Late Quaternary Relative Sea-Level Change on the West Coast of Newfoundland

Two revised relative sea-level (RSL) curves are presented for the Port au Choix to Daniel’s Harbour area of the Great Northern Peninsula, northwestern Newfoundland. Both curves are similar, showing continuous emergence of 120-140 m between 14 700 cal BP and present. The half-life of exponential curves fit to the RSL data is 1400 years and the rate of emergence varies from ~2.3 m per century prior to 10 000 cal BP to ~0.13 m per century since 5000 cal BP. The curves fit a general pattern of RSL history along the west coast of Newfoundland, where there is a southward transition from solely emergence to emergence followed by submergence. Isostatic depression curves are generated for four RSL records spanning the west coast. Almost double the crustal depression is recorded to the northwest, reflecting the greater glacioisostatic loading by the Laurentide Ice Sheet over southern Labrador and Québec compared to a smaller loading centre by a regional ice complex over Newfoundland. Only the St. George’s Bay RSL record in the southwest appears to show evidence for a proglacial forebulge, when at 6000 cal BP an isostatic ridge of 4 m amplitude begins to collapse.Deux courbes du niveau marin relatif (NMR) sont présentées pour la région allant de Port-au-Choix à Daniel’s Harbour sur la Grande Péninsule Nord, au nord-ouest de Terre-Neuve. Les deux courbes sont semblables, montrant une émergence continue de 120 à 140 m entre 14 700 cal BP et l’actuel. La demi-vie des courbes exponentielles ajustées au NMR est de 1400 ans, et le taux d’émergence varie de ~2.3 m par siècle avant 10 000 cal BP à ~0.13 m par siècle depuis 5000 cal BP. Les courbes s’ajustent au modèle général de l’histoire du NMR de la côte ouest de Terre-Neuve, où il existe une transition d’émergence seule à une émergence suivie d’une submergence, en allant vers le sud. Des courbes de dépressions isostatiques préliminaires sont générées pour quatre chronologies du NMR couvrant la côte ouest. Presque le double de la dépression de la croûte est enregistré au nord-ouest, reflétant la charge glacio-isostatique plus grande de l’Inlandsis Laurentidien sur le sud du Labrador et du Québec comparée à la charge plus faible du complexe glaciaire régional localisé sur Terre-Neuve. Seules les données du NMR de St. George’s Bay, au sud-ouest, semble démontrer l’affaissement du bourrelet périphérique lorsqu’une vague isostatique de 4 m d’amplitude commence à s’effondrer vers 6000 cal BP

Mitochondrial physiology

As the knowledge base and importance of mitochondrial physiology to evolution, health and disease expands, the necessity for harmonizing the terminology concerning mitochondrial respiratory states and rates has become increasingly apparent. The chemiosmotic theory establishes the mechanism of energy transformation and coupling in oxidative phosphorylation. The unifying concept of the protonmotive force provides the framework for developing a consistent theoretical foundation of mitochondrial physiology and bioenergetics. We follow the latest SI guidelines and those of the International Union of Pure and Applied Chemistry (IUPAC) on terminology in physical chemistry, extended by considerations of open systems and thermodynamics of irreversible processes. The concept-driven constructive terminology incorporates the meaning of each quantity and aligns concepts and symbols with the nomenclature of classical bioenergetics. We endeavour to provide a balanced view of mitochondrial respiratory control and a critical discussion on reporting data of mitochondrial respiration in terms of metabolic flows and fluxes. Uniform standards for evaluation of respiratory states and rates will ultimately contribute to reproducibility between laboratories and thus support the development of data repositories of mitochondrial respiratory function in species, tissues, and cells. Clarity of concept and consistency of nomenclature facilitate effective transdisciplinary communication, education, and ultimately further discovery

Mitochondrial physiology

As the knowledge base and importance of mitochondrial physiology to evolution, health and disease expands, the necessity for harmonizing the terminology concerning mitochondrial respiratory states and rates has become increasingly apparent. The chemiosmotic theory establishes the mechanism of energy transformation and coupling in oxidative phosphorylation. The unifying concept of the protonmotive force provides the framework for developing a consistent theoretical foundation of mitochondrial physiology and bioenergetics. We follow the latest SI guidelines and those of the International Union of Pure and Applied Chemistry (IUPAC) on terminology in physical chemistry, extended by considerations of open systems and thermodynamics of irreversible processes. The concept-driven constructive terminology incorporates the meaning of each quantity and aligns concepts and symbols with the nomenclature of classical bioenergetics. We endeavour to provide a balanced view of mitochondrial respiratory control and a critical discussion on reporting data of mitochondrial respiration in terms of metabolic flows and fluxes. Uniform standards for evaluation of respiratory states and rates will ultimately contribute to reproducibility between laboratories and thus support the development of data repositories of mitochondrial respiratory function in species, tissues, and cells. Clarity of concept and consistency of nomenclature facilitate effective transdisciplinary communication, education, and ultimately further discovery

Mitochondrial respiratory states and rate

As the knowledge base and importance of mitochondrial physiology to human health expands, the necessity for harmonizing the terminologyconcerning mitochondrial respiratory states and rates has become increasingly apparent. Thechemiosmotic theoryestablishes the mechanism of energy transformationandcoupling in oxidative phosphorylation. Theunifying concept of the protonmotive force providestheframeworkfordeveloping a consistent theoretical foundation ofmitochondrial physiology and bioenergetics.We followguidelines of the International Union of Pure and Applied Chemistry(IUPAC)onterminology inphysical chemistry, extended by considerationsofopen systems and thermodynamicsof irreversible processes.Theconcept-driven constructive terminology incorporates the meaning of each quantity and alignsconcepts and symbols withthe nomenclature of classicalbioenergetics. We endeavour to provide a balanced view ofmitochondrial respiratory control and a critical discussion on reporting data of mitochondrial respiration in terms of metabolic flows and fluxes.Uniform standards for evaluation of respiratory states and rates will ultimatelycontribute to reproducibility between laboratories and thussupport the development of databases of mitochondrial respiratory function in species, tissues, and cells.Clarity of concept and consistency of nomenclature facilitate effective transdisciplinary communication, education, and ultimately further discovery

Quaternary history, palaeo-geography and sedimentology of the Humber River Basin and adjacent areas

The Humber River basin in western Newfoundland was completely glaciated during the Quaternary. Glacial erosional features show an early southward ice flow from a source north of the basin that covered the coastal margins in the western part of the basin, including the Harrys River valley. Subsequent regional ice flow was southwestward to northwestward from a dispersal centre on The Topsails. South to southwestward flowing ice from the Long Range Mountains occupied the upper Humber River valley. This flow was confluent with ice from The Topsails flowing northwestward towards Bonne Bay. -- Ice retreated from the inner coast about 13 ka. During retreat, ice occupying the Deer Lake Valley dammed a proglacial lake in the adjacent Grand Lake basin to an elevation up to 85 m above present lake levels, as interpreted from strandlines on the west side and deltas on the east. This lake, named glacial Lake Howley, drained through its western end into the Harrys River valley via a well-defined channel. Drainage followed the modem Harrys River valley, reaching the sea in northern St. George's Bay. The lake was lowered by exposure of the South Brook valley outlet, and finally drained catastrophically through a spillway at Junction Brook. -- Marine incursion accompanied glacial retreat in the Deer Lake valley. Marine limit at the coast was 60 m asl, based on the elevation of a delta in the Hughes Brook valley. Inland deltas found at the head of Deer Lake and fine-grained sediment exposed within the Deer Lake valley show inundation below 45 m modem elevation. Dated marine macro-fossils in the Humber Arm and lower Humber River valley, indicate the deltas at the head of Deer Lake formed about 12.5 ka

Contemporary frontal moraine formation in the Yoho Valley, British Columbia

The northern terminus of Emerald Glacier (51ﾟ31'N, 116ﾟ32'W) in the Yoho Valley, British Columbia was bordered by a small, actively forming frontal moraine during summer 1979. Stratigraphic and morphological contrasts existed round the ice front, which primarily resulted from a contrast in the distribution of supraglacial debris. -- Sedimentological and geotechnical techniques were utilised to determine the origin of stratigraphic units within the moraine ridge. -- Moraine A, at the margin of heavily debris covered ice, exhibited a complex stratigraphy. At most sites a lens of subglacially derived till was evident, between units of supraglacially derived material. It is proposed that the moraine forming process involved the initial development of an ice-front talus apron, which was subsequently pushed and over-ridden. A plastic subglacial till was squeezed from beneath the supra-morainal ice margin, and overlain by a sorted supraglacial unit during glacier retreat. The moraine was actively advancing during the field season due to the maintenance of glacier-moraine contact resulting from the retardation of ice-melt afforded by the supraglacial debris cover. -- Moraine B is located at the margin of debris-free ice. The stratigraphy is less complex, although an upper unit representing a younger depositional phase was observed. The process of formation involved the melt-out of subglacial deposits during the summer months (July to August), which were bull-dozed into a ridge during winter advance. Successive accretions of till onto the proximal moraine side, perhaps on a annual basis, are suggested. -- Deterioration of climate, resulting in positive mass balances is the main cause of glacier advance. Positive balances have been recorded from nearby glaciers between 1973 and 1976. This suggests that small glaciers are sensitive indicators of periods of climatic deterioration. -- The thesis concludes that more than one moraine forming process may be observed around a single ice margin, one of which may be 'annual' in nature; and that complex moraines may be formed by depositional processes operating at the margin of a temperate glacier. If complexities exist in presently forming moraines, then such a possibility must be considered when examining deposits of past glaciations

Topographically-controlled Deglacial History of the Humber River Basin, Western Newfoundland

The Humber River in western Newfoundland flows through a large interior basin, that influenced Late Wisconsinan ice flow from major dispersal centres to the north, in the Long Range Mountains, and to the east in The Topsails. An early southward ice flow from a source to the north covered coastal areas in the western part of the basin. Subsequent regional ice flow was southwestward to northwestward from The Topsails, while south to southwestward flowing ice from the Long Range Mountains occupied the upper Humber River valley. This flow was confluent with ice from The Topsails and moved northwestward toward Bonne Bay. Regional deglaciation began about 13 ka from the inner coast. Ice occupying the Deer Lake valley dammed glacial Lake Howley in the adjacent Grand Lake and Sandy Lake basins to an elevation up to 85 m above present lake levels, which were controlled by drainage through a western outlet feeding into St. George’s Bay. The lake was lowered by exposure of the South Brook valley outlet, and finally drained catastrophically through a spillway at Junction Brook. Marine limit at the coast was 60 m asl. Inland deltas at the head of Deer Lake and fine-grained sediment exposed in the Deer Lake valley show inundation below 45 m present elevation. This produced a narrow embayment extending at least 50 km inland from the modern coast and is named here as ‘Jukes Arm’. Dated marine macrofossils in the Humber Arm and lower Humber River valley, indicate the deltas at the head of Deer Lake formed about 12.5 ka.Dans l’ouest de Terre-Neuve, le fleuve Humber draine un vaste bassin qui a influencé la direction des flux glaciaires, au Wisconsinien supérieur, à partir des principaux centres de dispersion situés au nord et à l’est. Dans l’ouest du bassin, les régions côtières ont d’abord été occupées par des glaces en provenance des monts Long Range, au nord. Par la suite, le flux glaciaire régional en provenance des Topsails, à l’est, s’est dirigé du sud-ouest vers le nord-ouest, tandis que la glace provenant des monts Long Range s’est écoulée vers le sud et le sud-ouest, occupant le secteur amont de la vallée du Humber. Les flux alors raccordés se sont par la suite orientés vers le nord-est, vers Bonne Bay. La déglaciation régionale a commencé il y a 13 000 ans environ, sur la côte. La glace, qui bloquait la vallée du Deer Lake, a créé le Lac glaciaire Howley, dans les bassins actuels des lacs Grand et Sandy, qui a atteint l’altitude de 85 m. À l’ouest, un exutoire assurait le drainage du lac vers St. George’s Bay. Dans la vallée du South Brook, le dégagement d’un exutoire a entraîné l’abaissement du niveau lacustre ; le drainage catastrophique du lac a été provoqué par la rupture d’un seuil au droit de Junction Brook. La limite marine a atteint 60 m sur la côte. Des deltas à la tête du Deer Lake et des sédiments fins dans la vallée témoignent d’une submersion ayant atteint 45 m, ce qui a engendré un bras de mer, appelé Jukes Arm, s’étendant sur plus de 50 km à l’intérieur des terres. Ces deltas se sont formés il y a 12 500 ans, d’après la datation d’organismes marins.El río Humber situado al oeste de Terranova irriga una gran cuenca interior de gran afluencia durante el Winconsiniano tardío. En esta área convergieron el flujo glacial proveniente de las montañas Longe Range al norte y de Topsails al este. Al oeste de la cuenca, la región costera fue inicialmente recubierta por el flujo de hielos provenientes del norte luego por el flujo glacial regional proveniente de Topsails. El flujo de Topsails se dirigió del sudoeste al noroeste, mientras que los hielos provenientes de Long Range se dirigieron hacia el sur y sudoeste ocupando así la parte superior del valle del río Humber. Posteriormente, su confluencia se orientó en dirección noreste hacia Bonne Bay. El deshielo regional se inicio hace aproximadamente 13 000 años en la región costera. Los hielos que ocupaban el valle del lago Deer formaron el lago glacial de Howley en la cuenca adyacente de los lagos Grand y Sandy a una altitud de 85 m sobre el nivel actual, siendo controlado por un afluente secundario que lo drenaba hacia la bahía St. Georges. El nivel del lago disminuyó al ser drenado hacia el valle South Brook y finalmente por un evento catastrófico que provocó la ruptura de un vertedero en Junction Brook. El limite marino en la costa fue de 60 m nmm. Los deltas situados a la cabeza del lago Deer y los sedimentos finos expuestos en el valle dan testimonio de la sumersión de hasta 45 m con respecto a la elevación actual. Ello provocó la formacion de un brazo de mar llamado Jukes Arm que se extendió 50 km. al interior de la costa. La datación de macro fósiles marinos provenientes del la rama del río Hamber y del valle sitúan la formación de dichos deltas hace aproximadamente 12 500 años