Element strongly positive

A strong positive correlation exists between Cu, Ag, Co, Au, W, and Se in the B and C horizon soil and suggests that these elements are geochemical pathfinders for sulfide mineralization at the Shiko Lake mineral occurrence. Glacial dispersal of Cu and Co in C horizon soil samples is characterized by the shape of geochemical profiles. These typically... 

The clay content (wt. %) (Fig. 2) shows a strong positive correlation with most element concentrations in the <250pm soil analyses, e.g. Cu (Fig. 3), with distinctly low values at 400 m east. In contrast, the clays show a well defined anomaly at the bottom of the profile at 400 m east (Fig. 4), with high concentrations of Ag, Cu, Au, Cd, Co, Bi, Se, and Mn. 

Contents of REE in massive sulfides from the BMC are strongly controlled by the abundance of and REE concentrations in phosphate minerals, specifically apatite, xenotime and monazite. Strong positive Eu anomalies in apatite, account for the anomalous Eu signatures of exhalative sulfides whereas REE in monazite masses are largely reflective of detrital sources and may mask hydrothermal signatures. Limited release of mobile trace elements (LREE and Eu) during green-schist facies metamorphism has partly modified REE profiles for VMS deposits of the BMC. 

Eased on two main lines of evidence, Niu et al. (1997) concluded that abyssal peridotites are the end products of melt extraction followed by variable amounts of olivine crystallization. First, in their set of reconstructed compositions they found that model fractional and batch melt extraction trends could not reproduce major and minor element variations in their data set. Most importantly, they found that melt extraction models failed to account for the strong positive correlation between FeO and MgO, as well as incompatible minor-element concentrations. Specifically, at a given Na20 or Ti02 content, abyssal peridotites are enriched in MgO relative to model melt extraction residues. Niu et al. (1997) showed that these compositional anomalies can be reconciled by a model of melt extraction followed by olivine crystallization, with more MgO-enriched samples having more accumulated olivine. If correct, this model has important implications for understanding melt extraction at oceanic ridges, and it has recently been the focus of re-evaluation. 

The dissolved Cu showed strong positive correlation with dissolved and exchangeable Mn whereas Cu and Mn were independent of Fe concentrations. It can be concluded from this observation that the elements Cu and Mn were independent of the scavenging effects of Fe. Only 2.8 percent of Cu and 10.9 percent of Mn were associated with the oxide fraction of solid phase as compared to 5.35 percent of Cu and 14.49 percent of Mn which were found to be associated with the carbonate fraction of the solid phase(13). It has been reported that generally, in the surface layers of natural waters, the conditions of pH and oxygen are such that Mn - introduced into these layers is readily oxidized to insoluble MnOa (40). This apparently was not true for the surface waters at SRP. The average pH of water samples examined at... 

Secondary structures are currently the most useful structural elements with respect to computer analysis. Secondary structrures are mostly known for RNAs and proteins but they also play important roles in DNA. Potential secondary structures can be easily determined and even scored via the negative enthalpy that should be associated with the actual formation of the hairpin (single strand) or cruciform (double strand) structure. Secondary structures are also not necessarily conserved in primary nucleotide sequence but are subject to strong positional correlation within the structure. Three-dimensional aspects of DNA sequences are without any doubt very important for the functionality of such regions. However, existing attempts to calculate such structures in reasonable time met with mixed success and cannot be used for a routine sequence analysis at present. 

Selenium, Te and Po combine directly with most elements, though less readily than do O and S. The most stable compounds are (a) the selenides, tellurides and polonides (M ) formed with the strongly positive elements of Groups 1, 2 and the lanthanides, and (b) the compounds with the electronegative elements O, F and Cl in which the oxidation states are 4-2, 4-4 and... 

Edmond et al. 1995 Table 13.3) and certain metals such as Cu, Co, Mo, and Se appear to show a strong positive temperature-concentration relationship which likely accounts for observed enrichments of these elements in the sulfides from high-... 

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