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Numerical simulations of tidal flow past Cape St. James on the south tip of Haida Gwai (Queen Charlotte Islands) are presented that indicate mesoscale dipoles are formed from coalescing tidal eddies. Observations in this region demonstrate robust eddy generation at the Cape, with the primary process being flow separation of buoyant or wind driven outflows forming large anti-cyclonic, negative potential vorticity, Haida Eddies. However, there are other times where dipoles are observed in satellites, indicating a source of positive potential vorticity must also be present. The simulations here build on previous work that implicates oscillating tidal flow past the cape in creating the positive vorticity. Small headland eddies of alternating vorticity are created each tide. During certain tidal cycles, the headland eddies coalesce and self organize in such a way as to create large >20-km diameter eddies that then self-advect into deep water. The self advection speed is faster than the beta drift of anti-cyclones, and the propagation direction appears to be more southerly than typical Haida Eddies, though the model contains no mean wind-driven flows. These eddies are smaller than Haida Eddies, but given their tidal origin, may represent a more consistent source of coastal water that is injected into to the interior of the subpolar gyre. [ABSTRACT FROM AUTHOR]

Gwaii Haanas National Park Reserve and Haida Heritage Site are located in British Columbia on the Queen Charlotte Islands archipelago, also known as Haida Gwaii. The Archipelago Management Board, which manages Gwaii Haanas National Park Reserve/Haida Heritage Site commissioned a comprehensive strategic tourism marketing effort to help ensure that tourism optimally contributes to the local heritage and the local quality of life. The study described in this paper was part of a larger research project developed to provide input to the tourism effort. The 1998 Queen Charlotte Islands/Haida Gwaii Visitor Survey and focus groups were developed in concert to obtain information useful to park management in understanding the region's tourism system, and to forecast the outcomes of various scenarios for future management. Integral to a sound plan is a clear understanding of visitors' images of the Queen Charlotte Islands/Haida Gwaii. Thus, this paper draws on the larger study to explore expectations and impressions of first-time visitors to Gwaii Haanas/Queen Charlotte Islands, a culturally and ecologically distinctive place. The goal of this paper is to enhance understanding of destination image shifts and the roles of visitation and information on place image. Results from 594 questionnaires and four focus groups shed light on the expected image and the resulting impressions held by first-time visitors to the Queen Charlotte Islands. Expectations were primarily related to attributes/features of the place (e.g., wildlife, Haida culture), while impressions were more evaluative of visitors' experiences at the destination (e.g., excellent, peaceful, etc.). Composition of individuals' images shifted from the destination environment (nature and culture) to their feelings about that environment (friendly, excellent, relaxing). This was evident in both survey and focus group results. The shift demonstrates a change from cognitive to affective image domains, providing further insight into components of image that are representative of first-time visitors. Information sources that played a role in creating visitors' images generally were not under direct control of the destination; for example, coffee table books and newspaper articles. Theoretical contributions of these findings are discussed and practical implications for destination image and strategic tourism efforts on Queen Charlotte Islands are offered. [ABSTRACT FROM AUTHOR]

In this paper, we examine the influence of the 27 October 2012, Mw 7.8 earthquake on landslide occurrence in the southern half of Haida Gwaii (formerly Queen Charlotte Islands), British Columbia, Canada. Our 1350 km2 study area is undisturbed, primarily forested terrain that has not experienced road building or timber harvesting. Our inventory of landslide polygons is based on optical airborne and spaceborne images acquired between 2007 and 2018, from which we extracted and mapped 446 individual landslides (an average of 33 landslides per 100 km2). The landslide rate in years without major earthquakes averages 19.4 per year, or 1.4/100 km2/year, and the annual average area covered by non-seismically triggered landslides is 35 ha/year. The number of landslides identified in imagery closely following the 2012 earthquake, and probably triggered by it, is 244 or an average of about 18 landslides per 100 km2. These landslides cover a total area of 461 ha. In the following years—2013–2016 and 2016–2018—the number of landslides fell, respectively, to 26 and 13.5 landslides per year. In non-earthquake years, most landslides happen on south-facing slopes, facing the prevailing winds. In contrast, during or immediately after the earthquake, up to 32% of the landslides occurred on north and northwest-facing slopes. Although we could not find imagery from the day after the earthquake, overview reconnaissance flights 10 and 16 days later showed that most of the landslides were recent, suggesting they were co-seismic. [ABSTRACT FROM AUTHOR]

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In the winter of 2010-2011 a large storm blew down an area of about 18 ha of mature coastal rainforest on East Limestone Island, Haida Gwaii, British Columbia. The area supported part of a breeding colony of Ancient Murrelets (Synthliboramphus antiquus). Observations of the timing of chick departures from this section of the colony in 2012 and 2013 suggested that daily timing of chick departures were delayed, on average, by about 30 min, compared with earlier years. This delay may have been caused by debris from the blowdown impeding the progress of chicks over the ground. A sharp decrease in the number of chicks leaving the blowdown area in 2014 may signify that some breeding pairs left the area following reduced breeding success. [ABSTRACT FROM AUTHOR]

This article documents the near-field effects of the largest tsunami of 2012 (globally), which occurred following Canada's second-largest recorded earthquake, on a thrust fault offshore western Haida Gwaii on October 28 (UTC). Despite a lack of reported damaging waves on the coast of British Columbia (largest amplitudes were recorded in Hawaii), three field surveys in the following weeks and months reveal that much of the remote unpopulated, uninstrumented coastline of western Haida Gwaii was impacted by significant tsunami waves that reached up to 13 m above the state of tide. Runup exceeded 3 m at sites spanning ~200 km of the coastline. Greatest impacts were apparent at the heads of narrow inlets and bays on western Moresby Island, where natural and manmade debris with a clear oceanward origin was found on the forest floor and caught in tree branches, inferring flow depths up to 2.5 m. Bays that see regular exposure to storm waves were generally less affected; at these sites a storm origin cannot be ruled out for the debris surveyed. Logs disturbed from their apparent former footprints on the forest floor at the head of Pocket Inlet provide evidence of complex runup, backwash and oblique flow patterns, as noted in other tsunamis. Discontinuous muddy sediments were found at a few sites; sedimentation was not proportional to runup. Lessons learned from our study of the impacts of the Haida Gwaii tsunami may prove useful to future post-tsunami and paleotsunami surveys, as well as tsunami hazard assessments. [ABSTRACT FROM AUTHOR]

A species of Lecanora in the L. dispersa group, with a well-developed pale thallus and a granular epihymenium, resembling L. albescens, is found exclusively on shoreline rocks and appears to be new. It is described as Lecanora schofieldii sp. nov., found mainly in the Pacific Northwest, but also rarely on the northeast coast. Its distinctions from similar species on shoreline rocks are given, together with a key for their identification. The first western record of L. xylophila from rocks is given. L'auteur rapporte une espèce de Lecanora du groupe L. dispersa montrant un thalle pâle bien développé, avec un épihyménium granulaire; on le retrouve exclusivement sur des rochers maritimes et ressemble au L. albescens, pouvant constituer une nouvelle espèce. L'auteur le décrit comme Lecanora schofieldii sp. nov., présent surtout dans le nord-ouest du Pacifique mais aussi, bien que plus rarement, sur la côte nord-est. Il présente les caractéristiques le distinguant d'espèces similaires des rochers maritimes ainsi qu'une clé pour leurs identifications. Il mentionne également pour la première fois dans l'ouest, le L. xylophila sur rochers. [ABSTRACT FROM AUTHOR]

The article presents a case study on the development of a geoferenced inventory and quality assurance species of the Haida Gwaii region in Canada. It states that the major goal of marine area conservation is assessing species diversity, which is a basic requirement for conservation and protecting biodiversity. Moreover, the starting the point for gathering regional biodiversity knowledge is the utility of georeferenced inventory.

Aim We used modern pollen assemblages to develop a method for climate reconstruction that reduces the spatial autocorrelation of residuals and accounts for the strong topographic and climatic variation that occurs in British Columbia, Canada. Location British Columbia, Canada, including sites both on the mainland and on adjacent islands (Queen Charlotte Islands and Vancouver Island). Methods New pollen assemblages from surface-sediment samples collected in British Columbia were combined with other published and unpublished samples ( n = 284). Multivariate rank-distances between sample sites and a randomized set of sites within the province were calculated for climate parameters to determine whether gaps in the current network of present-day pollen sample sites exist. Lacustrine surface-sediment pollen assemblages ( n = 145) were ordinated using non-metric multidimensional scaling (NMDS), and a generalized additive model (GAM) was used to reconstruct modern mean warmest month temperature (MWMT) and mean annual precipitation (MAP) from the NMDS ordination. The results were compared with standard climate reconstruction techniques, including the modern analogue technique, partial least squares, weighted averaging, weighted averaging–partial least squares and factor analysis. Results Reconstructions of MWMT and MAP using NMDS and GAM were comparable to those of existing models. When reconstructing MWMT, the NMDS/GAM method had a lower root-mean-squared error of prediction (RMSEP), lower spatial autocorrelation and higher correlation with observed temperature values than the other methods tested. When reconstructing MAP, the partial least squares method performed better than the NMDS/GAM method for RMSEP and correlation with observed values; however, the NMDS/GAM method had a lower spatial autocorrelation of residuals. Main conclusions NMDS reveals strong relationships among modern pollen assemblages, vegetation and climate parameters. Climate models using NMDS and GAM are comparable to other palaeoecological reconstruction models, but provide lower spatial autocorrelation of residuals for both parameters tested. An inverse distance-weighted surface of multivariate rank-climate distances generated from the network of pollen sample sites indicates that greater sampling intensity in north-western and central-interior British Columbia is required in order to obtain an accurate representation of climatic and vegetation diversity in the province. [ABSTRACT FROM AUTHOR]

The Queen Charlotte Fault zone is the transpressive boundary between the North America and Pacific Plates along the northwestern margin of British Columbia. Two models have been suggested for the accommodation of the ∼20 mm yr−1 of convergence along the fault boundary: (1) underthrusting; (2) internal crustal deformation. Strong evidence supporting an underthrusting model is provided by a detailed teleseismic receiver function analysis that defines the underthrusting slab. Forward and inverse modelling techniques were applied to receiver function data calculated at two permanent and four temporary seismic stations within the Queen Charlotte Islands. The modelling reveals a ∼10 km thick low-velocity zone dipping eastward at 28° interpreted to be underthrusting oceanic crust. The oceanic crust is located beneath a thin (28 km) eastward thickening (10°) continental crust. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Geographer is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Earth Sciences is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The article presents information on the histories of the gold crystal localities of British Columbia. The first reported locality was at the Queen Charlotte Islands in 1852. Its discovery sparked a minor gold rush in 1857. Other gold localities include the Cariboo Forest Region and Vancouver Island.

Presents a study which determined the relationships of the five species of ground beetles of the Nebria gregaria group, found on the Queen Charlotte Islands, British Columbia. Role of the glacial cycles of the late Pleistocene in the biogeography of North America; Information on the study organisms; Materials and methodology; Results and discussion.

Voluminous basalts dominate a middle Tertiary bimodal volcanic assemblage in the Queen Charlotte Islands, British Columbia, Canada. These moderately enriched mid-ocean-ridge basalt (MORB-)like magmas were associated with significant crustal extension related to the subduction of the Pacific–Farallon ridge and the initiation of a slab window environment, which persisted for 35 Ma. These asthenospheric melts were derived from a low degree of melting of a heterogeneous peridotite source mainly in the spinel stability field, as inferred from fractional melting inversion calculations. The basaltic magmas in turn gave rise to both tholeiitic and calc-alkaline volcanic strata up to 3.5 km thick in local grabens. The tholeiitic basalts resemble MORB, with rare-earth element (REE) patterns ranging from slightly depleted to enriched in light REE (LREE). The calc-alkaline basaltic andesites are enriched in LREE, but are not strongly depleted in Nb. The rocks have overlapping Nd, Sr, and Pb isotopic compositions, similar to those of intraplate basalts from the adjacent northeast Pacific seamounts and Cordillera. The difference between the tholeiitic and calc-alkaline rocks is, in part, attributed to polybaric fractional crystallization of different proportions of plagioclase to mafic minerals from a similar tholeiitic magma. This marginal-basin subalkaline volcanic sequence and its genesis describe the slab window environment for the Tertiary tectonics of the western Canadian continental margin and provide a model for older combined tholeiitic and calc-alkaline volcanic successions.De grands volumes de basaltes dominent un assemblage volcanique bimodale du Tertiaire moyen dans les îles de la Reine-Charlotte (Colombie-Britannique, Canada). Ces magmas, moyennement enrichis, de type basalte de la dorsale médio-océanique (MORB) ont été reliés à une importante extension crustale associée à la subduction de la dorsale Pacifique–Farallon et au commencement d'un environnement d'ouverture de plaque qui a duré 35 Ma. Ces fusions asthénosphériques ont été dérivées de la fusion partielle d'une source de péridotite hétérogène, surtout dans le domaine de la stabilité des spinelles, tel que déduit des calculs d'inversion des fusions fractionnelles. À leur tour, les magmas basaltiques ont produit des strates volcaniques tholéiitiques et calco-alcalines qui atteignent jusqu'à 3,5 km d'épaisseur dans des graben locaux. Les basaltes tholéiitiques ressemblent aux MORB avec des patrons d'éléments des terres rares (REE) qui vont de légèrement épuisés à enrichis en éléments de terres rares légers. Les andésites basaltiques calco-alcalines sont enrichies de REE légers, mais le Nb n'est pas fortement épuisé. Les roches ont des compositions isotopiques Nd, Sr et Pb qui se chevauchent, semblables à celles des basaltes intraplaques des monts sous-marins de la Cordillère et du Pacifique NE adjacents. La différence entre les roches tholéiitiques et les roches calco-alcalines est attribuable en partie à la cristallisation fractionnelle polybarique des différentes proportions de minéraux plagioclases à mafiques provenant d'un magma tholéiitique semblable. Cette séquence volcanique, en marge d'un bassin marginal sub-alcalin, et sa genèse décrivent l'environnement d'ouverture de plaque pour la tectonique du Tertiaire de la marge continentale de l'Ouest canadien et fournit un modèle pour les séquences volcaniques calco-alcalines et tholéiitiques combinées antérieures.[Traduit par la Rédaction] [ABSTRACT FROM AUTHOR]

The article discusses the aspects of a proposed model related to the sedimentological characteristics of the Honna Formation (HF) of sandstone from the Queen Charlotte Islands of Canada. They include: the assertion that the HF conformably overlies the Skidgate Formation, inference that the interbedded conglomerate and volcanic strata at Long Inlet are of Tertiary age and the case for differential rotation of small crustal blocks on Graham Island.