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The remote-sensing study of an exhumed upper Paleozoic surface in the southern Gaspé Peninsula of Quebec has provided indirect evidence for the presence of a previously unidentified post-Acadian (post—Middle Devonian orogeny) graben-fill unit. Subsequent work on stratigraphic sections in that area confirms that the graben-fill unit, the new Saint-Jules Formation, is indeed petrographically distinct and older than previously documented upper Paleozoic strata in that area, which were collectively assigned to the Viséan (Upper Mississippian) Bonaventure Formation. Paleogeographic reconstruction from sedimentary facies, paleocurrent, and provenance studies concurs with the geometric detail that was provided by the preliminary geomorphic study. The present paper therefore presents the case study of an upper Paleozoic stratigraphic unit that was first inferred by geomorphic constraints prior to being recognized in the field through the study of stratigraphic sections. The study underlines the stratigraphic relevance of analyzing exhumed paleosurfaces at the margins of ancient sedimentary basins. [ABSTRACT FROM AUTHOR]

Little is known about reproduction of the sea pen Pennatula aculeata, which is found at high densities and constitutes vulnerable habitat in the Gulf of St. Lawrence, Canada. Sex ratio, size at maturity, and reproductive status were investigated for colonies collected in May, August, and October 2015 along the Gaspé Peninsula. Reproductive status was assessed by histological determination of gamete sex and maturity and by stereomicroscope measurement of the diameters of the leading cohort of oocytes (LCO) or sperm cysts of histologically mature colonies. Colonies were gonochoric, with a sex ratio of 1:1. Based on the distribution of gamete diameters in May, three groups of female and a single group of male colonies were identified. Female colonies classified in the group of LCO with the smallest diameter (0.10–0.39 mm) were shorter in total length (TL < 130 mm) than females in the other two groups of LCOs with larger diameters, and very few spawned from May to October. A major reduction in the proportion of large female colonies (TL ≥ 130 mm) belonging to the group with the largest diameter (≥0.55 mm) and of mature male colonies between May and August indicated one annual spawning event. Persistence of histologically mature (vitellogenic) female colonies classified in the two smaller oocyte diameter groups after spawning is indicative of prolonged oogenesis (at least 24 months). The fact that only approximately half of the large female colonies had ripe oocytes (diameter ≥0.55 mm) in May prior to spawning, while the other half had vitellogenic oocytes of much smaller diameter which persisted after the spawning period, suggests that they reproduce only every other year. Estimated size and age at which 50% of colonies spawned were greater in females (148 mm TL, 11–14 years) than in males (101 mm TL, 8–11 years). These reproductive characteristics may reduce resilience of P. aculeata to various anthropic stressors. [ABSTRACT FROM AUTHOR]

Sea cucumber Cucumaria frondosa have highly variable whole body mass and length, and are usually sold to Asian markets as dried gutted body wall. Understanding the relation between size and yield of dry product is essential for resource conservation and for economic purposes. In this study, stock-specific mass and length recovery rates were estimated for C. frondosa captured by dredging or diving at various depths and seasons on the South shore of the St. Lawrence Estuary, along Gaspé Peninsula, and processed in a commercial plant. The processing yield in dry product mass per sea cucumber was more than 1.5 times larger for sea cucumbers collected at 26–47 m depth compared to those collected at 9–16 m depth. Within each strata, there was little variation in the processed body mass, seasonally or spatially. Recovery rates based on gutted mass for this stock (13.4─14.5%) varied little among depths and seasons, despite observed seasonal and bathymetric variation in reproductive status. In contrast, recovery rates based on whole body mass and length were highly variable both seasonally and spatially. Stress related to dredging or post-capture handling induced important variable body contraction and water content, leading to variation in body length, mass and shape of sea cucumbers having the same processed body mass. Gutted mass was the best metric to predict processed body mass and to estimate size whereas whole body length was the least reliable. New stock-specific information on variability of body mass, length, and recovery rates induced by capture, and on seasonal and bathymetric variation in reproductive status and processing yields will be used for the design of future stock assessment surveys, and for stock conservation. [ABSTRACT FROM AUTHOR]

This paper presents the development and assessment of a numerical method for simulated site calibration. The wind flow over complex terrain is predicted with a small length scale resolution. The flow field is resolved with the Reynolds averaged Navier-tokes equations, complemented by the k-υ turbulence model, with special treatment of the ground boundary to account for very large roughness lengths such as forest. The computational model is solved using FLUENT. A complex site, Riviere au Renard, located in Gaspesie, QC, Canada, has been selected and data have been collected from five met masts installed on this site. An experimental data analysis has been undertaken with emphasis on uncertainty evaluation. Three sets of results are presented. First, the numerical method is validated over flat terrain by comparing the simulation results with Monin-Obukhov similarity theory. Second, the assessment of the numerical method over complex terrain is done by comparing the wind velocity profiles at three of the met masts for three different wind orientations. Finally, traditional and numerical site calibrations for Riviere au Renard are presented for two wind directions. The numerical results are within the experimental data uncertainty. [ABSTRACT FROM AUTHOR]

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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.)

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.)

Studies the longitudinal and vertical variation in grain orientation and size in eight turbidite greywacke beds from the Cloridome Formation of Gaspé, Quebec, Canada. What the agreement between grain orientation and other internal current-direction indicators such as graptolites and intra-bed lineation signifies; Where the most significant grain orientations are observed; Specific characteristics of certain beds.