نتایج جستجو برای: sodic calcic and potassic alterations
تعداد نتایج: 16837401 فیلتر نتایج به سال:
In order to investigate the alteration products of rhyolitic tuffs under alkaline hydrothermal condition, samples of acidic pyroclastic rocks from Darabad area (N-E Tehran) were selected. Rock samples were examined under petrographic microscope, X-Ray powder diffraction, X-Ray Fluorescence and were eventually powdered and mixed with Na+ and K+ bearing solutions in hydrothermal autoclaves. The e...
in order to comparision of the micromorphic properties of saline-sodic and nonsaline-nonsodic soils in the west of urmia lake, four soil profiles (2profile in saline-sodic soils and 2profiles in nonsaline-nonsodic soils) were investigated. these profiles were described and sampled using standard methods. soil samples were used for physico chemical analysis and undisturbed and oriented samples w...
Soil alkalinisation generally constitutes a major threat to irrigated agriculture in the semiarid regions of West Africa. The improvement of sodic soils is generally difficult and expensive. However, a recent study in the Niger valley in NIGER, reveals that a natural dealkalinisation is possible under natural conditions in a semi-arid climate. Transformation of non-saline sodic soil into brown ...
Sodic soils have low organic carbon content, microbial load and their activities which were the biological indicators of soil health. Soil organic carbon is the kay factor which derives the soil functions. A field experiment was conducted to study the effect of different amendments and micronutrient mixture on soil biological properties. Gypsum+GM, DSW (distillery spent wash) and GLM (Glyricidi...
sakhtehesar mountain is located in urumieh-dokhtar magmatic belt and is composed of volcanic and subvolcanic rocks (pliocene andesite to dacite) which intruded the volcanics and pyroclastics of paleocene age. three alteration zones including potassic, phyllic and propylitic are recognized in the area. in this paper, the mineral chemistry of magmatic and primary biotite and the mineral chemistry...
Abstract A comprehensive mineralogical, geochemical and isotopic review of six ultramafic-alkaline-carbonatite magmatic intrusions the Shillong Plateau (Sung Valley, Jasra, Swangkre-Rongjeng, Mawpyut) Mikir Hills (Samchampi-Samteran Barpung) is presented here, using published data. These emplaced ca. 115–102 Ma ago, thus are significantly younger than tholeiitic flood basalts erupted in Rajmaha...
analytical results of 11 groundwater samples are used to evaluate the quality of groundwater in the hastijan area, (central province –iran). the main indices of water, ions physicochemical characteristics and the important heavy metals concentration studied. to estimate of water quality, piper, ghibbs, schoeller and wilcox diagrams, sodium absorption ratio, color-alkalinity and saturation index...
Many andesites erupted at arc volcanoes are the products of magma mixing, and this process could be important in triggering their eruption. Throughout life Ngauruhoe volcano (?2.5 ka), lack macroscopic enclaves or lithological features mingled magma. However, intricate microscopic mixing mingling occur. Plagioclase phenocrysts have a wide range textures. Their diverse 87Sr/86Sr values (0.7039–0...
prosopis cineraria (l.) druce (kahour in persian) is a native and indicative species of saharo-sindian region. prosopis forest in iran extends from the beach of persian gulf and oman sea in boushehr, hormozgan and sistan-baluchistan provinces to south of kerman province. in this research ecological conditions of prosopis such as floristic diversity, climate, soil and the biomass were studied. i...
Magmatic augites reacted with high temperature aqueous solutions to form secondary calcic pyroxenes during the subsolidus cooling of the Skaergaard intrusion. Secondary, hydrothermal clinopyroxenes replace wall rock igneous augites at the margins of veins filled with calcic amphibole. These veins are up to several millimeters wide and tens of meters in length. Hydrothermal clinopyroxenes are a ...
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