Résultats de la recherche (142 résultats)

Affinez votre recherche

Par Collection Par Auteur Par Date Par Sujet Par Titre
  • Road log to some abandoned gold mines of the gold-pyrite belt, Northwestern Virginia
  • Gold mass balance in lateritic profiles from savanna and rain forest zones
  • French Guiana ; Geochemistry ; Gold ; Laterite ; Mali ; Mineralization ; Palaeoclimate ; Pedogenesis ; Savanna ; Tropical rain forest ; Tropical zone ; Weathering
  • In this paper, the gold behavior in laterites was compared under a tropical contrasted climate in Banankoro, South Mali, and under an equatorial climate in Yaou, French Guiana. Gold distribution was studied in detail in terms of pedologic horizons
  • , and mass balance calculations of gold were applied to both sites in order to evaluate the extent of gold mobility for each type of weathered profile.
  • Geomorphological control of gold distribution and gold particle evolution in glacial and fluvioglacial placers of the Ancocala-Ananea Basin, Southeastern Andes of Peru
  • The AA. describe the pattern of gold distribution in glacial and fluvioglacial sediments of the Ananea-Ancocala basin. They analyze the grain size and shape characteristics of gold particles which are found in the sediments of this basin
  • . They examine the factors controlling the formation and evolution of gold placers in glacial and fluvioglacial geomorphological environments.
  • The development of agriculture in a Gold Rush region
  • Between 1848-1920, agriculture in the Sierra foothills of California supplied food for the gold mining camps. Except for farms along rail lines, this agriculture was subsequently abandoned. - (DWG)
  • Westerly derived Early Cretaceous gold paleoplacers in the Western Canada foreland basin, southwestern Alberta: tectonic and economic implications
  • Alberta ; Canada ; Geochemistry ; Gold ; Microstructure ; Mineralization ; Placer ; Sedimentary ; Sedimentary structure ; Stratigraphy ; Tectonics
  • This paper presents evidence for the occurence of detrital gold in fluvial sediments of Albian (Early Cretaceous) igneous-clast conglomerate lenses in the upper Beaver Mines and Mill Creek formations (Blairmore Group). The AA. show how this unusual
  • occurence has arisen as a consequence of the tectonic development of the eastern Canadian Cordillera. The results indicate local gold assay values exceeding those reported elsewhere in the province in either placers or paleoplacers.
  • Geomorphological evolution and supergene gold ore at Posse, Goias State, Brazil
  • Brazil ; Geochemistry ; Geomorphology ; Gold ; Laterite ; Leaching ; Mineralization ; Pedogenesis ; Weathering
  • At Posse, primary gold mineralization occurs near the base of a sequence of metamorphosed volcanic and volcaniclastic rocks. During the Velhas geomorphological cycle (Oligocene to Lower Pleistocene) the region experienced extensive lateritization
  • . The observed gold distribution in the weathering profile has arisen through saprolitization during the Velhas cycle, then leaching, compaction and downward (and limited lateral) transport of gold during pedogenesis. The climatic and geomorphological history
  • of central Brazil has led to the formation of a low grade supergene gold orebody in the weathering profile at Posse.
  • Sustained storage and transport of hydraulic gold mining sediment in the Bear River, California
  • California ; Catchment area;Watershed ; Fluvial processes ; Gold ; Human impact ; Mining activity ; Model ; Pollution ; Sediment transport ; United States
  • This study examines the large deposits of hydraulic gold mining sediment and reevaluates Gilbert's (1917) classic model of sediment transport in a symmetrical wave that is based on hydraulic mining sediment primarily in the Yuba Basin. Sustained
  • Cocaine : white gold rush in Peru.
  • Placer gold in eastern Peru: the great strike of 1942
  • Gold content in some sediments from Lebanon
  • Conservation versus artisanal gold mining in Corcovado National Park, Costa Rica : land use conflicts at neotropical wilderness frontiers
  • Costa Rica, which has the most advanced conservation agenda in Latin America, nevertheless is the scene of conflicts between farmers, miners and the government over access to protected forest lands. In 1985 over 800 gold miners were evicted from
  • Gold production in Central Asia
  • Extractive industry ; Former USSR ; Geological field ; Gold ; Mine ; Organization ; Production ; Soviet Central Asia ; Uzbekistan
  • Regional trends in Russian gold production
  • Enterprise ; Extractive industry ; Gold ; Industrial organization ; Mine ; Production ; Regional disparities ; Russia
  • Why people move to the Sun-belt: a case study of long distance migration to the Gold Coast, Australia
  • Australie ; Comportement ; Croissance démographique ; Décision ; Enquête ; Facteur de migration ; Gold Coast ; Héliotropisme ; Migration intérieure ; Méthodologie ; Satisfaction
  • Dimensions of environmental justice in anti-gold mining movements
  • Argentina ; Conflict ; Environmental justice ; Gold ; Mine ; Participation ; Scale ; Social movement
  • Fair trade gold : antecedents, prospects and challenges
  • Discourse ; Ghana ; Gold ; Handicrafts ; Living conditions ; Management ; Mine
  • The tropical cyclone threat to tho Queensland Gold Coast
  • Australie ; Catastrophe ; Comportement ; Cyclone tropical ; Gold Coast ; Géographie humaine ; Perception du risque ; Queensland ; Région touristique
  • Ardenne ; Belgium ; Gold ; Mine ; Mining activity