some small gabbro patches emplaced along the thrust fault with w-e trend in the vicinity of maien bolagh village at the ht/mp metapelites, a part of the central iran zone (near to sanandaj-sirjan zone). the coarse-grained dark gabbro samples consist of amphibole, clinopyroxene, plagioclase, minor quartz, titanite, and biotite. gabbros have high potassic calc-alkaline to shoshonitic affinity. th...

in order to determine the physico-chemical characteristics of oils from upper sarvak and dariyan formations, 4 oil samples collected from reshadat and resalat oilfields were analyzed. physical properties of oils (e.g. the api gravity), indicates that dariyan oil in both resalat and reshadat oilfield is similar to (with low pour points and high sulfur contents) the oils from sarvak reservoir. ba...

[1] Among aquatic and terrestrial landscapes of the McMurdo Dry Valleys, Antarctica, ecosystem stoichiometry ranges from values near the Redfield ratios for C:N:P to nutrient concentrations in proportions far above or below ratios necessary to support balanced microbial growth. This polar desert provides an opportunity to evaluate stoichiometric approaches to understand nutrient cycling in an e...

In the U.S., coal fired power plants produce over 136 million tons of coal combustion residuals (CCRs) annually. CCRs are enriched in toxic elements, and their leachates can have significant impacts on water quality. Here we report the boron and strontium isotopic ratios of leaching experiments on CCRs from a variety of coal sources (Appalachian, Illinois, and Powder River Basins). CCR leachate...

[1] Biogeochemical processes fractionate Ca isotopes in plants and soils along a 4 million year developmental sequence in the Hawaiian Islands. We observed that plants preferentially take up Ca relative to Ca, and that biological fractionation and changes in the relative contributions from volcanic and marine sources produce a significant increase in Ca in soil exchangeable pools. Our results i...

Abstract Most conventional statistical methods aiming at defining geochemical concentration thresholds for separating anomalies from background have limited effectiveness in areas with complex geological settings and variable lithology. In this paper, median+2MAD as a method of exploratory data analysis (EDA) and concentration-area (C-A) fractal model as two effective approaches in separation g...

A comparison is made of the probability of the process of two neutrino double beta decay for Se in direct (counter) and geochemical experiments. It is shown that the probability is systematically lower in geochemical experiments, which characterize the probability of ββ(2ν) decay a few billions years ago. The experimental data for Te are also analyzed. It is shown that geochemical measurements ...

Geochemical mapping programs carried out by the Geological Survey of Sweden (SGU) have generated large databases containing information on the concentrations of chemical elements in rocks, surface sediments and biogeochemical materials. Regional geochemical data being imprecise, multivariate, spatially auto-correlated and non-normally distributed pose specific problems to the choice of data ana...

Evidence of biochemical and geochemical evolution was sought in insoluble carbonaceous matter from 30 selected pre-Phanerozoic sediments ranging in age from about 3.8 to about 0.7 x 10(9) years. The carbon isotope ratios observed were in the range of -20 to -32 per mil with reference to the Peedee belemnite standard, similar to those previously reported. No systematic trends are obvious to us. ...