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[en] The Semipalatinsk test site territory became available to geological research only in 1991, after stopping of nuclear tests. From information concerning the mineral deposits, we can learn about the geological heritage. The test site area has a unique combination of naturally-influenced and human-influenced geologic sites. These need research, classification, description, and preservation in order the use the geological heritage. (author)
[en] This book analyses the works of the French Geological Survey for 1987. Main results are given in summary form only which are indexed separately when they concern an energy related activity such as nuclear method chemical analysis, well logging or underground radioactive waste disposal
[fr]Ce livre analyse les travaux du BRGM pour 1987. Les principaux resultats sont resumes et ceux-ci sont indexes separement lorsqu'ils concernent une activite liee a l'energie comme les methodes nucleaires d'analyse chimique, la diagraphie ou l'elimination des dechets radioactifs dans des formations geologiques
[en] This report is about the geochemical prospect ion results carried out in the Otegui and Ombu hill anomalous zones of Lavalleja town as well as its location, geochemical and geologic information
[en] The 1973 bibliography is revised and reindexed to include all useful material published during the postwar period through 1973. It excludes most abstracts, environmental impact statements, and reports not available to the public. It does include reports that are unavailable because they are out of print if they can be found in the files of industry geologists and some company libraries. Appendices include US government publications listed by number and a cross reference by topic
[en] Survey geologists are doing extensive work in northern Saskatchewan mapping selected areas of the Precambrian Shield with a view to delineating, and understanding the formation of, uranium-bearing deposits. Underwater exploration techniques are being perfected and the federal-provincial Uranium Reconnaissance Program conducted five projects. (E.C.B.)
[en] Conducted a detailed analysis of the seismicity of Armenia and adjacent areas. Defined dual character of seismicity in the region, which is expressed as the stepped seismic activity and the frequency increased seismic regime; periods of activation are approximately: 12 and 24 hours, as well as 14 and 28 days. There is also an annual cycle of increased seismicity. Detailed examination revealed the nature of the seismicity and allowed more profound understanding of the physical and geological-tectonic processes leading to the appearance of strong earthquakes in the region. Provides recommendations for the design survey prognostic observation networks for precursors of earthquakes
[en] This work brings information of fields and laboratory samples about the outcrop in Treinta y Tres district in the framework of limestones programme carried out jointly with I.G.U and BGR through the geological German mission
[en] Dickinsonia in the central Urals occurs in a succession transitional from marginal marine to non-marine. Even within this sequence Dickinsonia appears to be restricted to the least marine facies interpreted as a coastal lagoon surrounded by tidal flats. Another puzzling aspect is the complete absence of other Ediacaran taxa that are usually found together with Dickinsonia in other fossil localities. In fact, the Sinii Kamen Member of the Cherny Kamen Formation yielded an assemblage of Ediacaran macrofossils including aspidellamorph and mawsonitomorph holdfasts, frondomorphs, palaeopascichnids, and concentric ring structures of microbial origin; however, fossils of Dickinsonia have never been found in this association.
[es]En los Urales centrales, Dickinsonia se encuentra en medios de transición entre sustratos continentales y marinos marginales, generalmente de tipo laguna costera rodeada por llanuras mareales. Otro aspecto llamatico es la ausencia de otros taxones ediacáricos asociados con Dickinsonia, relativamente abundantes en otros medios. De hecho, el Miembro de Sinii Kamen de la Formación de Cherny Kamen ha librado una asociación de macrofósiles ediacáricos, que incluye anclajes de tipo aspidellamorfo y mawsonitomorfo, frondomorfos, palaeopascichnidos y estructuras en anillos concéntricos de origen microbiano, con los que no se asocia Dickinsonia.
[en] The mid-Cenomanian Mishrif Formation (Fm.) is considered as one of the most important rudist-bearing reservoir horizons in the Sirri Oil Fields of the Persian Gulf. Due to the general heterogeneity of carbonate reservoirs, the use of an integrated approach is helpful for investigating porosity and permeability distribution along with recognizing controlling pore system factors in the reservoir. Thus, for the reservoir characterization of the Mishrif Fm., an integrated approach including facies analysis, diagenetic history and sequence stratigraphic analysis is considered. Detailed petrographic studies showed a total of eight microfacies and seven facies belts, related to inner ramp to the basin of a homoclinal carbonate ramp. Humid climatic condition and tectonic activity, associated with eustatic sea-level fluctuations during the mid-Cretaceous, led to meteoric diagenesis of the Mishrif carbonates during subaerial exposures (mid-Cenomanian and Cenomanian-Turonian disconformities). General diagenetic overprints and modifications include micritization, cementation, dissolution, compaction, dolomitization, pyritization and fracturing. Considering this reservoir in the sequence stratigraphic framework reveals that the reservoir zones development is basically related to the Cenomanian–Turonian sequence boundary, recognized in the three studied wells, and also to the mid-Cenomanian boundary, identified only in one well. In addition, pore system properties were inspected by differentiation of Hydraulic Flow Units (HFUs) within the reservoir. The identified flow units, based on their capability for fluid flow, can be classified into four main rock types with very high- (HFUD), high- (HFUC), medium- (HFUB) and low-quality (HFUA). Accordingly, this study shows that the main part of the Mishrif Reservoir is affected by diagenetic processes related to subaerial exposures, resulting in zones with higher storage capacity and fluid flow rates. So, the study of depositional and diagenetic characteristics of the Mishrif carbonates in the sequence stratigraphy framework is essential to unravel the reservoir heterogeneity, and to describe the reservoir zones and their distribution in the field and regional scale. In addition, observed changes in the thickness of hydrocarbon column are attributed to the different location of the studied wells on the anticline structures, which show a tilted oil-water contact with a slope to the North.
[en] Geomorphological indices, such as the Stream Length-Gradient (SL) index, have been demonstrated to be suitable for detecting anomalies in stream-profiles. These anomalies (knickpoints) are generally related to active tectonics, lithological changes and large mass movements. This study aims to detect drainage areas affected by mass movements using SL index in La Vall d’Àssua, Romadriu and La Vall de Tor basins (Central Pyrenees). The methodology used consists of computing the SL index using the Chi-Map script and then, applying two ArcGIS® tools, which are the Hotspot and Cluster Analysis (HCA) and Kernel Density (KD), to provide a better visualisation and location of the knickpoints. SL anomalies have been compared with the slope failure inventory of La Vall d’Àssua basin, indicating a good correlation between SL anomalies and slope failures. Additionally, this geomorphological index provided the identification of 13 mass movements which had not previously been described. To sum up, this geomorphological parameter is a useful tool for the identification of drainage network areas affected by mass movements
[es]Los índices geomorfológicos, como el índice del gradiente del perfil longitudinal de los ríos (Stream LengthGradient index, SL) han demostrado ser buenos identificadores de anomalías en los perfiles longitudinales de los ríos. Generalmente, los factores más comunes que producen estas anomalías (knickpoints) son principalmente cambios litológicos, estructuras tectónicas activas y grandes movimientos de ladera. Este estudio se propone detectar zonas de la red de drenaje afectadas por movimientos en masa utilizando el índice SL en las cuencas de La Vall d’Àssua, Romadriu y La Vall de Tor (Pirineos Centrales). La metodología utilizada consiste en calcular el índice SL utilizando la herramienta Chi-Map y, después, se han aplicado las herramientas Análisis de Puntos Calientes (Hotspot and Cluster Analysis, HCA) y Densidad de Kernel (Kernel Density, KD) de ArcGIS® para proporcionar una mejor visualización y localización de los valores anómalos del índice SL. Las anomalías de SL han sido comparadas con el inventario de inestabilidades de ladera existente en la cuenca de La Vall d’Àssua. Los resultados obtenidos de este análisis indican que hay una buena correlación entre anomalías de SL y los movimientos en masa. Además, este índice geomorfológico ha ayudado en la identificación de 13 nuevas inestabilidades de ladera en el conjunto de las tres cuencas analizadas. En conclusión, el estudio realizado ha permitido comprobar la utilidad del índice SL para detectar aquellos puntos de la red de drenaje que están afectados por movimientos en masa.