In response to addressing potassium (K) deficiency in soil and decreasing agricultural production costs, the potential of K-bearing phyllosilicate minerals that can be directly used as an alternative K source has been investigated using sodium tetraphenylboron (NaTPB) extraction and an intensive cropping experiment. The results showed that the critical value of K-release rate and leaf K concent...

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...

The Jiaodong Peninsula is the most important gold mineralization area in China, and formation of deposits closely related to granitoids. isotopic ages Early Cretaceous granodiorites northwestern are concentrated range 111~123 Ma, coeval with area. However, studies on geotectonic settings granodiorites, especially their petrogenesis relationship Peninsula, scarce. Based field petrographic observ...

Chlorite flakes, as a product of alteration of biotite, the dominant ferromagnesian mineral in the Paleozoic granitic rocks of the Canadian Appalachians, have been analyzed by electron microprobe for major elements and by 57Fe M?ssbauer spectroscopy for the coordination and oxidation state of Fe. Comparison of M?ssbauer Fe3+/Fe ratios obtained from chlorite and its host biotite indicates that c...

The deposits of Eocene Lake Gosiute that constitute the Green River Formation of Wyoming contain numerous tuff beds that represent isochronous, correlatable stratigraphic markers. Tuff beds selected for Ar/Ar analysis occur within laminated mudstone, are matrix supported, and lack evidence of reworking. These tuffs contain 2%–15% euhedral phenocrysts of quartz, plagioclase, sanidine, biotite, a...

The Southern Highland Group (Dalradian) and Keltie Water Grit Formation, which includes the Lower Cambrian Leny Limestone, form an inverted, 1.4 km thick, largely arenaceous, sequence at Callander. The grits have the same detrital mineralogy throughout, mainly quartz, plagioclase (An1–3), muscovite, and biotite. Chlorite formed from detrital biotite during low-grade regional metamorphism (T<270...