Results 161 to 170 of about 210,813 (245)

Nanoparticulate apatite and greenalite in oldest, well-preserved hydrothermal vent precipitates. [PDF]

Sci Adv
Rasmussen B, Muhling JR, Tosca NJ.
europepmc   +1 more source

Light δD apatites reveal deep origin water in North China Craton intracontinental granites and basalts. [PDF]

Nat Commun
Yang CM, Xu YG, Xia XP, Yang JH, Huang XL, Spencer CJ, Sun JF, Yang Q.   +7 more
europepmc   +1 more source

Mafic slab melt contributions to Proterozoic massif-type anorthosites. [PDF]

Sci Adv
Keller DS, Lee CA, Peck WH, Monteleone BD, Martin C, Vervoort JD, Bolge L.   +6 more
europepmc   +1 more source

Occurrence and lithogeochemical composition of iron ore in Ngororero District, Rwanda. [PDF]

Heliyon
Nshimiyimana C, Chisakulo E, Nsengiyumva C.   +2 more
europepmc   +1 more source

Chemical aspects of hydrothermal alteration with emphasis on hydrogen metasomatism

Economic Geology, 1964
The ratio of cation to hydrogen-ion concentration is used as a basis for coordinating many observed varieties of silicate rock alteration. Low ratios drive alteration from feldspar through sericite, montmorillonite, or paragonite, toward kaolinite or pyrophyllite.
W. R. Jones, J. J. Hemley
semanticscholar   +4 more sources

GIANT HYDROTHERMAL HEMATITE DEPOSITS WITH Mg-Fe METASOMATISM: A COMPARISON OF THE CARAJAS, HAMERSLEY, AND OTHER IRON ORES

Economic Geology, 2004
The genesis of banded iron formation (BIF)-hosted high-grade hematite deposits has been debated for nearly a century. Recent worldwide recognition of magnetite- and/or hematite-, carbonate-, and talc-rich mineralization, deep below the modern weathering in these deposits, and recognition of Mg-Fe metasomatism in wall rocks implies that hydrothermal ...
Hilke J. Dalstra, Sergio Guedes
semanticscholar   +5 more sources

Seawater-metasomatism in hydrothermal sediments (Escanaba Trough, northeast Pacific)

Chemical Geology, 1995
Abstract Hydrothermal sediments from the NESCA vent-field, Escanaba Trough, are enriched in a number of typical “vent-fluid” metals for which fluid data for the same, sediment-hosted, site exhibit anomalous depletion. These results are consistent with cooling of rising fluids and precipitation of various metal sulphide, sulphate and oxide phases in ...
B.A. Barreiro, E. M. Ludford, T.A. Nelsen, Martin R. Palmer, Christopher R. German, N.C. Higgs   +5 more
semanticscholar   +5 more sources

Fluid flow and metasomatism in a subduction zone hydrothermal system: Catalina Schist terrane, California

Geology, 1989
On Santa Catalina Island, southern California, bluechist to amphibolite facies metasedimentary, metamafic, and meta-ultramafic rocks show veining and alteration that reflect fluid flow and mass transfer at 25-45 km depths in an Early Cretaceous subduction zone. Synkinematic and postkinematic veins record fluid transport and metasomatism during prograde
Mark D. Barton, Gray E. Bebout
semanticscholar   +4 more sources

The Arba'at Granite, Sudan: a mineralised, Pan-African intrusion enhanced by hydrothermal metasomatism

Journal of African Earth Sciences, 1997
Abstract The granite at Arba'at shows many of the chemical features of a metallogenetically specialised A-type granite, although no economic mineralisation has yet been found there. The specialised character is, however, only strong within the aphyric granites of low density forming the interior of the intrusion.
A.A. Osman, Farouk Ahmed, David C. Almond   +2 more
semanticscholar   +4 more sources

Metasomatism in the Whin Sill of the North of England. Part II: Hydrothermal Alteration by Juvenile Solutions

Geological Magazine, 1929
In Teesdale and Weardale, at all exposures that have been examined, the Whin Sill is cut by a system of approximately vertical, sweeping, joint planes. These are distinct in general character from, and are on a larger scale than, the columnar jointing which is conspicuous in all vertical scars of Whin Sill. The pattern of the larger scale jointing on a
L. R. Wager
semanticscholar   +4 more sources