Results 11 to 20 of about 222,262 (199)

Hydration of silica and its role in the formation of quartz veins - Part 2 [PDF]

Substantia, 2019
The aqueous chemistry of silica and the formation of abundant polymeric silica species in natural sediment accumulations is set out in Part 1. Part 2 continues to describe the amorphous silica in sediments and presents more evidence for the formation of ...
John Elliston
doaj   +2 more sources

Antimony quartz and antimony-gold quartz veins from northern Portugal [PDF]

Geochimica et Cosmochimica Acta, 2006
Abstract Antimony- and Pb–Sb-quartz veins from the Braganca district, Portugal, are mainly hosted by Silurian phyllites. Antimony–Au-quartz veins from the Durico–Beira region are mainly hosted by a Cambrian schist–metagraywacke complex, as well as Ordovician phyllites and quartzites.
Neiva, A. M. R., András, P., Ramos, J. M. F.   +2 more
openaire   +4 more sources

Tourmaline-quartz-cassiterite mineralization of the Land's End Granite at Nanjizal, west Cornwall [PDF]

, 2002
Nanjizal is one of the few locations in the southern segment of the Land's End Granite (Early Permian) where magmatic-hydrothermal tin mineralization has been worked. Three principal mineralization episodes are recognized.
A.V. Bromley (21814982), RK Shail (21814886), G.S. Camm (21814973), N. Hoppe (21814985), N.G. LeBoutillier (21814913), C. Jewson (21814916)   +5 more
core   +6 more sources

Pseudo-two-girdles c-axis fabric patterns in a quartz-feldspar mylonite (Costabona granodiorite, Canigo massif) [PDF]

, 2012
An example of the relationship that exist between the preferred crystaliografic orientation of quartz grains and the attitude of the mylonite foliation of quartz-feldspar mylonites is described. These rocks are the result of the inhomogeneous deformation
Casas Tuset, Josep Maria
core   +6 more sources

Platinum mineralization in quartz veins near Naboomspruit, central Transvaal

, 1995
Quartz veins which transect felsites and sandstones of the Transvaal Sequence near Naboomspruit contain locally high concentrations of platinum. These were exploited between 1924 and 1926 by Transvaal Platinum Ltd.
Tredoux, M., McDonald, I., Vaughan, D. J.   +2 more
core   +10 more sources

Origin and pathways of pro- and retrograde fluids, PTt paths and fluid-mineral equilibria from Alpine veins of the Central Alps : case studies of the Fibbia and Amsteg areas [PDF]

, 2006
In order to constrain the conditions of and processes related to vein formation and the origins of mineralising fluids, field work, multiple geochemical methods applied to whole rocks, minerals, and fluid inclusions, as well as thermodynamic modeling ...
Heijboer, Tjerk Cornelis
core   +1 more source

Metamorphic Rock-Hosted Orogenic Gold Deposit Type as a Source of Langkowala Placer Gold, Bombana, Southeast Sulawesi

Indonesian Journal on Geoscience, 2014
DOI: 10.17014/ijog.v6i1.114In 2008, placer gold was discovered in Langkowala area (Bombana Regency), Southeast Sulawesi, Indonesia, and more than 60,000 traditional gold miners in the early 2009 have been operating by digging vertical pits and panning ...
Arifudin Idrus, I. Nur, I. W. Warmada, Fadlin Fadlin   +3 more
doaj   +1 more source

A Randomized Trial Comparing Treatments for Varicose Veins [PDF]

, 2014
BACKGROUND: Ultrasound-guided foam sclerotherapy and endovenous laser ablation are widely used alternatives to surgery for the treatment of varicose veins, but their comparative effectiveness and safety remain uncertain. METHODS: In a randomized trial
Ramsay, Craig R, J Scott, Wileman, S., Elders, Andrew, Baker, Sara A., M Gough, G Scotland, Scott, Julian, Scotland, G., Gough, Michael, M K Campbell, E Tassie, J Norrie, S Baker, Burr, Jennifer, Campbell, Marion K, S Wileman, Campbell, Marion K., Burr, J., Bachoo, P., Ramsay, C. R., Lees, T., Baker, S. A., Earnshaw, J., Francis, J., Elders, A., Burr, J. M., Baker, S., S C Cotton, Brittenden, J., Campbell, Marion Kay, Norrie, John, Baker, Sara A, B Campbell, Francis, Jill, J Francis, Tassie, Emma, Scott, J., J M Burr, A Elders, J Earnshaw, Bachoo, Paul, C R Ramsay, Brittenden, Julie, Ramsay, Craig R., Gough, M., Chetter, I., Cotton, S. C., Lees, Tim, Tassie, E., T Lees, Campbell, Bruce, Wileman, Samantha, Campbell, M. K., Chetter, Ian, Campbell, B., Cotton, Seonaidh C, Cotton, Seonaidh C., Neil Stewart, Earnshaw, Jonothan, J Brittenden, Scotland, Graham, Norrie, J., P Bachoo, I Chetter   +64 more
core   +1 more source

Quartz Vein Geochemistry Records Deformation Processes in Convergent Zones

Geochemistry, Geophysics, Geosystems, 2021
In several examples of subduction zones, we compared pairs of quartz veins formed either at the lower temperatures of the seismogenic zone (260°C or below), or at the higher temperatures of its downdip limit (∼330°C). All the veins analyzed here are mode
Hugues Raimbourg, Kristijan Rajič, Benjamin Moris‐Muttoni, Vincent Famin, Giulia Palazzin, Donald Fisher, Kristin Morell, Saskia Erdmann, Ida Di Carlo, Clément Montmartin   +9 more
doaj   +1 more source

The origin and evolution of the ore-forming fluids at the Manondo-Choma gold prospect, Kirk range, southern Malawi

Open Geosciences, 2023
This study provides an in-depth analysis of fluid inclusions (FIs) and stable isotopes from the Manondo-Choma gold prospect in southern Malawi to understand the ore-forming mechanisms, genesis, and evolution of the hydrothermal fluids responsible for ...
Chisambi Joshua, von der Heyden Bjorn
doaj   +1 more source