GEOSCAN, résultats de la recherche


TitreThe application of seismic shothole drillers' log records to the understanding of permafrost, ground ice, bottomfast ice, and granular aggregate resources in the Mackenzie - Beaufort region
AuteurSmith, I R
SourceCanada - United States Northern Oil and Gas Research Forum, Program and Abstracts; 2011 p. 26-27
LiensOnline - En ligne
LiensPresentation - Présentation
Séries alt.Secteur des sciences de la Terre, Contribution externe 20110100
RéunionCanada - United States Northern Oil and Gas Research Forum; Calgary; CA; Novembre 30 - décembre 2, 2011
Mediaen ligne; numérique
ProvinceTerritoires du Nord-Ouest; Yukon
Sujetspergélisol; congélation du sol; glace fossile; températures au sol; ressources granulaires; aggrégats; glace massive; géologie des dépôts meubles/géomorphologie; géologie de l'ingénieur
Programmepipeline nordiques, Géosciences environnementales
Résumé(disponible en anglais seulement)
This research discusses the recent database compilation of >275,000 seismic shothole drillers' log records from northern Yukon and the Northwest Territories. These previously, largely unused records have provided a wealth of baseline, near-surface (10-60 m) geoscience information that has enabled the publication of several new and original GIS-based geoscience interpretations and models.
Characteristics of permafrost and distribution of massive ice and ground ice is often understood in detail at monitoring stations, but may be poorly constrained on regional bases. While the seismic shotholes are generally too shallow to constrain permafrost depths in the Mackenzie ' Beaufort region, they do record 100s of instances of sub-surface unfrozen sediments. These records reflect both hazards to development, and highlight aspects of channel migration and lake drainage that is of key concern to infrastructure planning and design. The shothole database also has 2111 records of massive ice, and 11,666 records of ground ice, providing far greater understanding of their distribution and character than presently exists. Bottomfast ice formation in near-shore marine areas also represents a significant hazard to pipelines and related infrastructure. There are 12,069 shothole records that constrain bottomfast and floating ice extents and provide a temporal record of conditions that largely predates satellite-based observations.
Identification and delineation of granular aggregate resources is one of the key development constraints in the arctic. The shothole records are ideally suited to identifying new potential resources owing to the drillers' propensity for recording gravel and other granular aggregates. Also, in areas characterized by extensive bog and muskeg, the drillers' logs can serendipitously identify surface and subsurface deposits that otherwise have no geomorphic expression.
Application of this research to the Alaskan North Slope and Beaufort coast is considered of high potential to resolve similar issues of terrain hazards and environmental constraints to oil and gas exploration and development.