نتایج جستجو برای: albitization

تعداد نتایج: 33  

Journal: :journal of sciences, islamic republic of iran 2016
k. khoshnoodi m. yazdi m. behzadi m. gannadi-maragheh

the study area is located in the central iranian tectono-magmatic zone, which is known for its world-class ioa-type iron ore deposits. the advanced space borne thermal emission and reflection radiometer (aster) and landsat enhanced thematic mapper plus (etm+) image-processing techniques, were used in satellite imagery through conventional and also modern processing methods including band ratios...

Journal: :Journal of Structural Geology 2021

Exhumed faults in granitoids along the Lanterman Fault-Rennick Graben Fault system (northern Victoria Land, Antarctica) show superposed ductile to brittle deformation and pervasive hydrothermal fluid-rock interaction. These processes triggered multiple slip events producing crosscutting epidote prehnite-rich fault veins, ultracataclasites pseudotachylytes of crushing origin. Combined microstruc...

Journal: :Geologica Acta 2021

Post-collisional mafic dykes crosscut the Paleozoic metamorphic basement and late-Variscan plutons in Les Guilleries massif (Catalan Coastal Ranges, NE Iberia). The predominance of phenocrysts, porphyritic texture, abundant amphibole, high MgO volatile content, together with crustal-like trace-element patterns indicate that correspond to calc-alkaline lamprophyres, mainly spessartites. Their en...

Journal: :Geochemistry Geophysics Geosystems 2022

Abstract Aseismic megathrust slip downdip of the seismogenic zone is accommodated by either steady creep or episodic slow events (SSEs). However, geological conditions defining rheology remain elusive. We examined exhumed subduction mélanges on Kyushu, Japan, which deformed at ∼370–500°C under greenschist to epidote‐amphibolite facies conditions, comparable warm‐slab environments. The recorded ...

Journal: :Minerals 2021

Previous geochemical and petrological studies have concluded that initially magmatic Nb–Ta mineralization is often modified by post-magmatic hydrothermal fluids; however, there still a lack of mineralogical evidence for the syenite-related deposit. From perspective minerals, pyrochlore supergroup minerals significance indicating fluid evolution alkaline rock or related carbonatite type deposits...

2006
J. P. K. A. RODGERS

A LENSOID mass of serpentinite is continuously exposed over some 650 m along the trace of the NNE.-trending Waipa Fault at Wairere (38~ 33" S., 175 ~ 2' E.) south of Te Kuiti (Fleming, 1948; O'Brien, I97O). Extensive quarrying of the deposit has revealed the presence of numerous highly-altered xenoliths of gabbro ranging in size from hand specimens to about 12o m a and exhibiting strongly groov...

Journal: :Bulletin Mineralogie Petrologie 2023

Classical locality Vyskočilka in the Barrandian Basin displays a well-exposed section of black Silurian shales penetrated by ca. 10-m thick diabase sill. We examined petrographic character and mineral composition intrusive body enclosing shales, as well hydrothermal veins cutting rocks. The is rock with basic affinity (paleobasaltoid), which was strongly influenced post-magmatic alterations inc...

Journal: :Minerals 2023

Greisenization is typically linked with highly fractionated granites and often associated hydrothermal vein systems. Late to postmagmatic metasomatic processes involve the enrichment of volatile components such as boron halogens well several metallic elements. The purpose this study reveal main effects paragenetic sequences related mineralizations in Highiş granitoids, Romania. In a natural out...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید