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Hydrothermal alteration and earth surface rock weathering: a basalt example
  • Hydrothermal alteration and earth surface rock weathering: a basalt example
Weathering or hydrothermal alteration?
  • Weathering or hydrothermal alteration?
  • Altération hydrothermale ; Arénisation ; Australie ; Bega ; Cristallin ; Dartmoor ; England ; Granite ; Géographie physique ; Hydrothermal ; Météorisation ; Royaume-Uni
Intrusion of basaltic sills into highly porous sediments, and resulting hydrothermal activity
  • Intrusion of basaltic sills into highly porous sediments, and resulting hydrothermal activity
  • California, gulf ; Dépôt hydrothermal ; Escarpement de faille ; Fond sous-marin ; Guaymas, basin ; Géographie physique ; Hydrothermal ; Pacifique Nord-Est ; Pacifique, îles ; Rift ; Roche ; Sill basaltique ; Sédimentaire ; Sédimentation ; Volcanisme
  • Sill intrusions into highly porous sediments in the Guaymas Basin, Gulf of California, lead to low-grade metamorphism, thermal alteration and migration of organic compounds, marked changes in interstitial water chemistry, and large-scale expulsion
  • of heated pore fluids. The latter process creates space for the intruding magma and initiates a hydrothermal system, which can explain the observed hydrothermal deposits around fault scarps on the basin floor.
Reconstruction of hydrothermal karst system in Zn-Pb sulphite deposits Upper Silesian Region, Poland
  • Reconstruction of hydrothermal karst system in Zn-Pb sulphite deposits Upper Silesian Region, Poland
  • Hydrothermal alteration ; Karst ; Karstification ; Ore geology ; Poland
Mineralogical and geo-chemical characterization of a diapiric formation in the North of Spain
  • Cantabria ; Diapir ; Domaine semi-aride ; Espagne ; Géochimie ; Hydrothermal ; Minéralogie ; Propriétés du sol ; Sol
  • Cantabria ; Diapir ; Geochemistry ; Hydrothermal ; Mineralogy ; Semi-arid area ; Soil ; Soil properties ; Spain
  • The AA. study a diapiric zone located in the Miranda-Treviño Depression, in the southern part of the Basque-Cantabrian Basin. They have selected 7 profiles : 3 soils formed on basic rock of volcanic origin (ophite) and rich in alterable minerals, 3
  • conditions in the study zone, together with the processes of extrusion and hydrothermal activity affecting the formation of the diapir, that are responsible for the genesis of the minerals.
Le associazioni paragenetiche idrotermali e supergeniche dell'area di Tresnuraghes (Sardegna occidentale, Italia) come possibile guida alla prospezione di metalli preziosi
  • Applied geology ; Hydrothermal alteration ; Italy ; Mineralogy ; Mining exploration ; Sardegna
  • Kaolin deposits and a wide range of hydrothermal minerals occur at Tresnuraghes district. As the hydrothermal processes could be related to epithermal precious metal deposition, spatial/temporal zonation of the newformed minerals was studied
Mobility and fractionation of rare earth elements during weathering of a granodiozite
  • largely result from mineralogical controls. Submarine and subaerial weathering processes may affect REE similarly, producing intensively weathered materials appreciably depleted in the REE. Spilitisation and hydrothermal alteration processes may affect
  • The rare earth elements (REE) have been mobilised and fractionated during supracrustal alteration of the Torrongo granodiorite. Compared with the parent granodiorite, incipiently and moderately altered rocks are particularly enriched in the heavy
  • REE, while the extremely altered residual products are especially depleted in the heavy REE. Mobilisation of the REE probably results from PH changes of soil and ground waters as they encounter different chemical environments while fractionation may
A Budai-hegység hidrotermális karsztja
  • Karst hydrothermal dans les monts Buda
  • Dolomie ; Grotte ; Géomorphologie ; Hongrie ; Hydrothermal ; Karst ; Modelé karstique ; Montagne ; Roche carbonatée
  • Carbonate rock ; Cave ; Dolostone ; Geomorphology ; Hungary ; Hydrothermal ; Karst ; Karstic landform ; Mountain
  • The paper presents the locally variable impacts of hydrothermal processes and provides explanations for the hydrothermal karst in the mountains. According to the A. neither dripstone formation, nor the major cave systems carved out by the mechanical
  • erosion of streams can be excluded from among karst phenomena. Author regards the Buda Hills (Hungary) a prototype of hydrothermal karst. - (JS)
Smectite formation produced by weathering in a coarse granite saprolite in Galicia (NW Spain)
  • The study of a granitic weathering profile in southern Galicia has shown the presence of smectites, which cannot be explained by poor drainage or by hydrothermal alteration. As the soil is polycyclic, the AA. cannot rule out the possibility
Scenarii du climat de la région de Moscou jusqu'en 2050
  • Climatic variation ; European part of Russia ; Hydrothermal alteration ; Model ; Moscow ; Oblast ; Precipitation ; Scenario ; Solar radiation ; Temperature ; Twenty-first century
Fe and Mn oxides at seafloor hydrothermal vents
  • Fe and Mn oxides at seafloor hydrothermal vents
  • Action biogène ; Dorsale océanique ; Fer ; Fond sous-marin ; Géochimie ; Hydrothermal ; Manganèse ; Minéralisation ; Minéralogie
  • Biogenic process ; Geochemistry ; Hydrothermal ; Iron ; Manganese ; Mineralization ; Mineralogy ; Oceanic ridge ; Sea floor
  • This paper describes the occurence and distribution of Fe and Mn oxides associated with hydrothermal activity on the mid-ocean ridges and discusses some of the mineralogical and chemical characteristics of the Fe and Mn precipitates. Studies of Fe
  • and Mn oxides at seafloor hydrothermal vents have focussed primarily on the inorganic precipitation of metals, but routine mineralogical and chemical analyses of these deposits reveal abundant microbial forms and organic carbon which suggest
Hydrothermal manganese in the Galapagos Rift
  • Hydrothermal manganese in the Galapagos Rift
A deep-sea hydrothermal site on a strike-slip fault
  • A deep-sea hydrothermal site on a strike-slip fault
  • Faille ; Fond sous-marin ; Géographie physique ; Hydrothermal ; Marge continentale ; Pacifique Est ; Pacifique, îles ; San Clemente fault zone ; Source thermale ; Volcanisme
  • Submersible exploration of a young scarp in the San Clemente fault zone, at 1,800m in the California Borderland, discovered tall piles of hydrothermal barite and dense colonies of large benthic animals. Phenomena along this active strike-slip fault
Geothermal exploration of the Reykholt thermal system in Borgarfjordur, west Iceland
  • Champ hydrothermal ; Géochimie ; Géographie de l'Europe ; Hydrochimie ; Hydrothermal ; Islande ; Source chaude
  • Etude du plus grand champ hydrothermal à basse température d'Islande. Les eaux thermales sont d'origine météorique. (JCB).
The application of advanced space-borne thermal emission and reflection (ASTER) radiometer data in the detection of alteration in the Chadormalu paleocrater, Bafq region, Central Iran
  • The application of advanced space-borne thermal emission and reflection (ASTER) radiometer data in the detection of alteration in the Chadormalu paleocrater, Bafq region, Central Iran
  • ASTER ; Crater ; Data processing ; Geological deposit ; Hydrothermal alteration ; Iran ; Iron ; Mineralogy ; Remote sensing
Relationships between clay mineralogy, hydrothermal metamorphism, and topography in a Western Cascades watershed, Oregon, USA
  • Relationships between clay mineralogy, hydrothermal metamorphism, and topography in a Western Cascades watershed, Oregon, USA
  • Argile minéral ; Bassin-versant ; Coulée boueuse ; Dynamique de versant ; Etats-Unis ; Hydrothermal ; Minéralogie ; Métamorphisme ; Oregon ; Roche volcanique
  • Clay mineral ; Hydrothermal ; Metamorphism ; Mineralogy ; Mudflow ; Oregon ; Slope dynamics ; United States of America ; Volcanic rock ; Watershed
  • This study investigates variation in clay mineralogy and its relation to hydrothermal metamorphism, hillslope processes, and topography in the western Cascade Mountains. The study area is the drainage basin of Dorena Lake, a medium-sized watershed
Vorkommen und Entstehung von tri-oktaedrischen Smektiten in den Basalten und Boden der Konig-Georg-Insel (S-Shetlands/West-Antarktis) (Occurrence et genèse d'une smectite tri-octoédrique dans les basaltes et les sols de King George Island (S-Shetlands/Antarctique ouest))
  • properties the saponite should have been formed by hydrothermal alteration of the primary Mg-Fe-minerals olivine and clinopyroxene.
Contribution of remote sensing techniques to the identification and characterization of Miocene calderas, Lesvos Island, Aegean Sea, Hellas
  • characteristics related with caldera structures such as topographic caldera rims and floors, ring faults, areas of hydrothermal alteration, drainage networks and lava domes, both internal and external to caldera structures. Six caldera structures are reported here
In situ determination of the hydrothermal properties of a deep fractured medium by a single-well technique in Hydrogeothermal studies. 26th International geological congress.
  • In situ determination of the hydrothermal properties of a deep fractured medium by a single-well technique in Hydrogeothermal studies. 26th International geological congress.
  • Expérimentation ; Géographie physique ; Hydrogéologie ; Hydrothermal ; Milieu fissuré ; Milieu poreux ; Propriété physique ; Technique de recherche
Galapagos hydrothermal mounds: stratigraphy and chemistry revealed by deep-sea drilling
  • Galapagos hydrothermal mounds: stratigraphy and chemistry revealed by deep-sea drilling
  • Fond sous-marin ; Galapagos ; Géochimie ; Géographie physique ; Hydrothermal ; Manganèse ; Pacifique Sud ; Pacifique, îles ; Rift ; Stratigraphie
  • Le système hydrothermal des monts sous-marins des Galapagos est au moins âgé de 300 000 ans et a produit des sédiments pauvres en manganèse qui ont presque recouvert la zone. Les dépôts actuels sont limités et riches en manganèse, suggérant un