Download Free Geological Survey Of Canada Current Research Online 2007 D1 Book in PDF and EPUB Free Download. You can read online Geological Survey Of Canada Current Research Online 2007 D1 and write the review.

Dans le cadre de la partie 2 du projet sur les ressources énergétiques des Appalaches de l'Initiative géoscientifique ciblée, nous avons utilisé un étinceleur pour obtenir plus de 3000 km de profils sismiques monotrace à haute résolution dans l'estuaire du Saint-Laurent. Ces données, recueillies en 2003 et 2004 en vue de cartographier des séries sédimentaires à de faibles profondeurs, contiennent de nombreux artéfacts, par exemple des réflexions multiples de courte et de longue périodes. Afin de fournir dans la mesure du possible des profils sans artéfacts, nous avons établi un processus à 10 étapes qui a servi pour le traitement des 55 profils obtenus. Ce processus comporte un algorithme de déconvolution trace par trace qui permet de comprimer la signature de la source. Les profils traités fournissent une image sismique améliorée qui permet de sélectionner avec précision les réflecteurs stratigraphiques clés.
New geophysical techniques (multibeam echo sounding and 3D seismics) have revolutionized high-resolution imaging of the modern seafloor and palaeo-shelf surfaces in Arctic and Antarctic waters, generating vast quantities of data and novel insights into sedimentary architecture and past environmental conditions. The Atlas of Submarine Glacial Landforms is a comprehensive and timely summary of the current state of knowledge of these high-latitude glacier-influenced systems. The Atlas presents over 180 contributions describing, illustrating and discussing the full variability of landforms found on the high-latitude glacier-influenced seafloor, from fjords and continental shelves to the continental slope, rise and deep-sea basins beyond. The distribution and geometry of these submarine landforms provide key information on past ice-sheet extent and the direction and nature of ice flow and dynamics. The papers discuss individual seafloor landforms, landform assemblages and entire landsystems from relatively mild to extreme glacimarine climatic settings and on timescales from the modern margins of tidewater glaciers, through Quaternary examples to ancient glaciations in the Late Ordovician.
This volume, covering metals and minerals, contains chapters on approximately 90 commodities. In addition, this volume has chapters on mining and quarrying trends and on statistical surveying methods used by Minerals Information, plus a statistical summary.
As the importance and dependence of specific mineral commodities increase, so does concern about their supply. The United States is currently 100 percent reliant on foreign sources for 20 mineral commodities and imports the majority of its supply of more than 50 mineral commodities. Mineral commodities that have important uses and face potential supply disruption are critical to American economic and national security. However, a mineral commodity's importance and the nature of its supply chain can change with time; a mineral commodity that may not have been considered critical 25 years ago may be critical today, and one considered critical today may not be so in the future. The U.S. Geological Survey has produced this volume to describe a select group of mineral commodities currently critical to our economy and security. For each mineral commodity covered, the authors provide a comprehensive look at (1) the commodity's use; (2) the geology and global distribution of the mineral deposit types that account for the present and possible future supply of the commodity; (3) the current status of production, reserves, and resources in the United States and globally; and (4) environmental considerations related to the commodity's production from different types of mineral deposits. The volume describes U.S. critical mineral resources in a global context, for no country can be self-sufficient for all its mineral commodity needs, and the United States will always rely on global mineral commodity supply chains. This volume provides the scientific understanding of critical mineral resources required for informed decisionmaking by those responsible for ensuring that the United States has a secure and sustainable supply of mineral commodities.