Elemental concentration patterns

There were a few sherds with totally unique compositional patterns, and these will probably not be placed, at least until much more is known of the elemental concentration patterns for the whole Near East. In this category is a group (1 in Table VIII) of nine sherds having the same pattern unfortunately none of these have forms recognizable to the Hesi archaeologists. 

Considerable progress is being made in the development of regional scale receptor modeling. There is surprisingly little variation of relative elemental concentration patterns of fine particles associated with various back-trajectory groups in the Ohio River Valley. 

It is possible to distinguish whether airborne metals arise from crustal sources, e.g., windbome soil and rocks, or from anthropogenic sources by comparing the elemental concentration patterns of airborne... 

Let us suppose that dust particles have been collected in the air above a city and that the amounts of p constituents, e.g. Si, Al, Ca,..., Pb have been determined in these samples.The elemental compositions obtained for n (e.g. 100) samples, taken over a grid of sampling points, can be arranged in a data matrix X (Fig. 34.1). Each row of the table represents the elemental composition of one of the samples. A column represents the amount of one of the elements found in the sample set. Let us further suppose that there are two main sources of dust in the neighbourhood of the sampled area, and that the particles originating from each source have a specific concentration pattern for the elements Si to Pb. These concentration patterns are described by the vectors s, and Sj. For instance the dust in the air may originate from a power station and from an incinerator, having each a specific concentration pattern, sj = [Si, Al, Ca , ... PbJ with k = 1,2. 

Element distribution patterns in till around the MFN deposit are most likely the result of concentration of anionic species in the gossan, glacial dispersal of metal-rich bedrock, and mobilization of... 

The difference in the element concentration in the vicinity of mineralization relative to background is small and single element anomalous patterns extend a maximum of several tens of metres from mineralization. Significant differences in... 

When the results of the yellow limestone clay and the red field clay analyses were processed by the potstat routine (10), an average of data from the two clays yielded a pattern that matched (except for sodium) the analytical pattern of pottery made of a mix of the two clays. In the first case, the two raw clays were simply ground and analyzed separately in the second case, the two clays were mixed in a water bath, sand and Dead Sea salt were added, a vessel was formed, dried, and fired, and this finished product was analyzed. The sand temper did not contribute significantly to the relative test element concentrations, but the salt addition did, of course, raise the sodium concentration. These results are graphed in Figure 2. 

As reported by Olmez and Gordon (University of Maryland), the concentration pattern of rare earth elements on fine airborne particles (less than 2.5 micrometers in diameter) is distorted from the crustal abundance pattern in areas influenced by emissions from oil-fired plants and refineries. The ratio of lanthanum (La) to samarium (Sm) is often greater than 20 (crustal ratio is less than 6). The unusual pattern apparently results from tlie distribution of rare earths in zeolite catalysts used in refining oil. Oil industry emissions have been found to perturb the rare earth pattern even in very remote locations, such as the Mauna Loa Observatory in Hawaii. 

The applications of activation analysis are almost innumerable. In the physical sciences, activation analysis is used in trace-element analysis of semiconductor materials, metals, meteorites, lunar samples, and terrestrial rocks. In most cases, the multielemental analysis feature of activation analysis is used to measure the concentrations of several trace-elements simultaneously. From these detailed studies of trace-element abundance patterns, one has been able to deduce information about the thermal and chemical history of the Earth, moon, Mars, and meteorites, as well as the source or age of an object. 

For chemical analysis, we used a mild acid-extraction procedure, based on recent experimental work (13, 26, 36, 37). We chose the extraction procedure over total digestion of the sample (35) because we are interested specifically in anthropogenic inputs by way of inorganic P and other elements, and not the total compositional chemistry (i.e., anthropogenic and diagenetic inputs). The extractant we used, composed of 20 ml of dilute 0.60 molar hydrochloric acid and 0.16 molar nitric acid, has been experimentally determined to remove soluble and readily labile P and other elements. While the extraction is not always proportional to the total P (or other elements) in soil, for activity area research we are concerned with the spatial patterns of elemental concentrations rather than absolute concentrations, as many variables affect elemental levels in soils (39, 40). 

In general, as noted in the previous discussion on probabilities, trace elemental concentrations in juices of Florida origin were found to be lower than those of non-domestic origin. Therefore, three cases were utilized to test the efficiency of the pattern recognition decision vector. 

Rhyolites exhibit variable concentrations of major and trace elements, with Palmarola showing higher incompatible trace element and lower Sr contents than Ponza (Fig. 6.19). Peralkaline rhyolites are strongly enriched in Rb, Th and other incompatible elements. REE patterns are fractionated, with rhyolites showing negative Eu anomalies, which are stronger at Palmarola (Fig. 6.20a). Incompatible element patterns (not shown) have mod-... 

The alkaline mafic volcanics are less enriched in silica and more enriched in incompatible trace elements than oversaturated tholeiitic rocks with similar MgO contents. REE show smooth and fractionated patterns (Fig. 9.7). Mantle normalised incompatible element patterns of mafic rocks generally display a small upward convexity with moderate enrichments in Ta and Nb. The large majority of the mafic volcanic rocks exhibit positive spikes of Ba and Pb, which are small or absent in the southern outcrops of Capo Ferrato, Guspini and Rio Girone (Fig. 9.7). Silicic volcanics exhibit a large range of incompatible element concentrations. Sr- and Nd-isotopic... 

We summarize noble gas amounts in deep-sea and subaerial sediments in Figure 5.1. From the data displayed here, we calculated median values which are shown in Table 5.1. Both Figure 5.1 and Table 5.1 show that even though there is little difference in the lighter noble gas concentration between subaerial and deep-sea sediments (He, Ne, and Ar), heavier noble gases are much more abundant in subaerial sediments than in deep-sea sediments. As in volcanic rocks (cf. Section 6.6), most sediments, either deep-sea or subaerial, show fractionation toward the heavier ones relative to air noble gas, although the mechanism for the fractionation may be different. Figure 5.2 shows noble a gas elemental abundance pattern relative to the air abundance subaerial sediments show much more severe fractionation. 

In this study we have employed the simultaneous collection of atmospheric particles and gases followed by multielement analysis as an approach for the determination of source-receptor relationships. A number of particulate tracer elements have previously been linked to sources (e.g., V to identify oil-fired power plant emissions, Na for marine aerosols, and Pb for motor vehicle contribution). Receptor methods commonly used to assess the interregional impact of such emissions include chemical mass balances (CMBs) and factor analysis (FA), the latter often including wind trajectories. With CMBs, source-strengths are determined (1) from the relative concentrations of marker elements measured at emission sources. When enough sample analyses are available, correlation calculations from FA and knowledge of source-emission compositions may identify groups of species from a common source type and identify potential marker elements. The source composition patterns are not necessary as the elemental concentrations in each sample are normalized to the mean value of the element. Recently a hybrid receptor model was proposed by Lewis and Stevens (2) in which the dispersion, deposition, and conversion characteristics of sulfur species in power-plant emissions... 

Coefficients of the elemental concentrations on the first principal component (Table II) show the pattern expected for a temper-related dimension the signs are positive for all variables except K and Ba, which are negative. Thus, the group separation on principal component No. 1 shown in Figure 6 can be interpreted as temper-related. As expected, the two major groups evident on the plot are (I) hypothetical fine-paste mixtures along with raw clay and (2) hypothetical medium-paste mixtures along with real sherds. 

Because geochemically different clay sources may have been used by potters to produce ceramics for both domestic and trade purposes, neutron activation analysis (NAA) has been used as an independent means of ceramic characterization. Because of the relatively good analytical precision possible with NAA, statistical patterning of NAA data for major, minor, and trace element concentrations may be used as a powerful provenancing tool. 

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