Deep Regolith Weathering on the Summit Surface of the Southern Mount Lofty Ranges,South Australia: a Contribution to the ‘Laterite’ Debate

Chemical and mineralogical analyses of samples from a 102 m deep borehole and from road cuts on the summit surface of the Mount Lofty Ranges near Willunga Hill, are used to assess critically the view that the regolith here developed as a result of tropical, so‐called ‘lateritic’ weathering processes that developed a standard ‘laterite’ profile of great antiquity. There is no evidence of a former surface crust that comprises the upper part of a ‘standard laterite profile’. Moreover, there is no dramatic variation in chemical composition down the profile, with largely in situ localised weathering transformations explaining mineralogical variability. The presence of 2:1 layer silicates and the absence of gibbsite do not favour the operation of former intense tropical weathering, but the possible presence of chloritised smectite may have inhibited gibbsite formation. An iron‐depleted pallid zone does not occur at depth in the profile, but is present on the plateau margin. Many of the weathering features exposed in the road cuts can be explained in terms of modifications and developments under environmental conditions similar to those of the present, arguing against the view that the summit surface and its associated weathering mantle have been preserved in pristine form since the Mesozoic.     

Secular variations in seawater chemistry as a control on the chemistry of basinal brines: test of the hypothesis

The hypothesis that basinal brines inherited their major ion chemistries and elevated salinities from evaporated paleoseawaters is tested by comparing the compositions of basinal brines in Silurian (Michigan basin, Illinois basin, Appalachian basin in eastern Ohio) and Jurassic/Cretaceous (Central Mississippi Salt Dome basin, Arkansas shelf, and south‐central Texas) host rocks, when the world oceans were ‘CaCl₂ seas’, with those from Permian and Pennsylvanian rocks (Palo Duro basin, Central Basin Platform, and Delaware basin, Texas and New Mexico) when the world oceans were ‘MgSO₄ seas’. Basinal brines examined are assumed to have originally formed from evaporation of the same seawaters that produced major evaporites. Sulfate, Mg and K levels in basinal brines are below the concentrations expected from evaporation of seawater of any type, which emphasizes the importance of diagenetic mineral–brine interactions in controlling basinal brine chemistry. There are no major differences in SO₄, Mg and K concentrations between basinal brines hosted by rocks originally formed during ages when the world oceans were MgSO₄ seas versus CaCl₂ seas. Basinal brines in Pennsylvanian–Permian rocks are compositionally distinct (relatively high Na and low Ca) from basinal brines in Silurian, Jurassic and Cretaceous host rocks, which may reflect original differences in seawater chemistry. Basinal brines enriched in Ca and depleted in Na relative to evaporated seawater of any type have traditionally been interpreted to form by albitization of plagioclase feldspar. A new explanation for Ca enrichment and Na depletion of basinal brines is the mixing of evaporated CaCl₂‐type seawater with more dilute water. Some basinal brines are similar in major ion composition to evaporated seawater of a particular age, for example basinal brines in the Cretaceous Edwards Group carbonates, Texas, where dolomitization is the only reaction required to convert evaporated Mesozoic CaCl₂ seawater into Edwards Group brine.     

Accurate identification of the pastry contained in a ceramic pot excavated from Jurou Li's grave from the Jin dynasty (1115–1234 ce) in Xi'an,Shaanxi, China

In order to identify accurately the circular object contained in the ceramic pot excavated from Jurou Li's grave of the Jin dynasty (1115–1234 ce ) in Xi'an, Shaanxi, China, mass spectrometry was applied to determine the amino acid sequences of the residual proteins extracted from the sample, after preliminary starch grain analysis. The sequences were searched against a standard protein sequence database. The proteins extracted were identified as originating from domesticated barley (Hordeum vulgare), soybean (Glycine max), and fermentative microorganisms (Kluyveromyces lactis, Lipomyces starkeyi, Wickerhamomyces ciferrii, Nadsonia fulvescens and Zygosaccharomyces rouxii). These findings indicate that the extremely degraded object in the ceramic pot was made from barley by fermentation with the addition of soy sauce, providing direct evidence of culinary culture in the Jin dynasty.     

Identifying domestic functional areas. Chemical analysis of floor sediments at the Classical-Hellenistic settlement at Düzen Tepe (SW Turkey)

For over a decade, multi-element chemical analysis of floor sediments in archaeological contexts has been a tool to identify and interpret anthropogenic chemical residues and activities. For the current study, a multi-element chemical analysis was applied to floor samples from a Classical-Hellenistic courtyard building at Düzen Tepe (SW Turkey). Among a series of 19 elements analyzed, K, Mg, Fe, P and Sr are thought to directly reflect anthropogenic chemical residues. The elements Cr, Mg, Ni, Pb and Ti are considered to reflect the geological background of the site, yet their contents seem to vary over different chemical residue zones, making them a suitable tool for delineating activity areas. Overall, the sampling and analysis techniques applied at Düzen Tepe – mild acid sample extraction and ICP-OES analysis – have proven to be fit for this kind of study. The analyses allow human activity zones within the study area to be identified and interpreted and deliver insights into the archaeological contexts that could not be obtained by archaeological research alone.     

A re-assessment of Basketmaker II cave 7: massacre site or cemetery context

Our ongoing investigation of early maize farming in the American Southwest has entailed stable isotope analysis and accelerator radiocarbon dating of Basketmaker II remains from sites in the Four Corners region. Here we report radiocarbon dates on a large mortuary assemblage excavated by Richard Wetherill in 1893 from a burial cave in southeastern Utah. It has long been thought that all individuals interred in Cave 7 were massacred in a single violent attack given embedded projectiles and evidence for blunt force trauma. However, accelerator radiocarbon dates on purified bone collagen (n = 96) do not lend strong support to this argument, even among the subset of individuals with clear evidence for violent injuries. Moreover, nearly 80% of Cave 7 burials examined in the study show no evidence of perimortem trauma and no adult females or subadults under the age of 12 appear to have suffered violent deaths. Rather than an anomalous single-event massacre, the Cave 7 radiocarbon dataset suggests that raiding and intra-group, male/male violence was episodic among Basketmaker groups in southeastern Utah. Population densities were relatively high and individuals interred in Cave 7 and elsewhere in the region were heavily dependent on maize agriculture, a prehistoric economic strategy typically characterized by high amplitude fluctuations in productivity. Variability in the array of grave goods accompanying Cave 7 male burials and elsewhere suggests competitive social differentiation likely heightened during periods of resource shortfall leading to intra-group conflict, raiding and perhaps ritualized acts of violence.     

Let no space go to waste: comparing the uses of space between two Late Classic centers in the El Paraíso valley,Copan, Honduras

Phosphorus analysis of earthen and plaster floors has been used in Mesoamerica to locate and identify activities at ancient sites. This study uses phosphorus analysis to discern if the inhabitants of two Late Classic coeval and proximal sites located in the El Paraíso Valley of Honduras were different culturally from each other. The buried earthen and plaster surfaces of both sites were systematically sampled and analyzed for phosphorus remains. The patterns of elevated phosphorus from these open spaces were subsequently compared to determine if differences in the habitual use and treatment of open spaces could be discerned. These differences are evaluated as a function of behavioral norms, functional responses, and cultural dispositions in order to evaluate the extent to which these two populations were indeed different from each other.     

Strontium and calcium distribution in plants: Effect on palaeodietary studies

In palaeodietary studies it is assumed that no discrimination occurs during uptake by plants of calcium and strontium from the soil. Here, a compilation of distribution ratios is presented from which it is apparent that differences in Sr/Ca ratios within and between plants do exist. These differences affect Sr intake by humans and animals and thus should be taken into consideration when interpreting prehistoric human bone Sr levels in a dietary sense, and when selecting a herbivorous baseline species. In agricultural societies, human Sr intake may be diversified by differences in Sr/Ca ratios in various grain species and varieties.     

Identification of activity area signatures in a reconstructed Iron Age house by combining element and lipid analyses of sediments

One promising analytical method used in household archaeology in addition to inorganic (element) geochemical analysis is that of organic (lipid) analysis applied to anthropogenic sediments. We use both methods here to review chemical imprints that might be useful for recognizing space use and identifying daily activities in a reconstructed Iron Age village at Lejre, Denmark. As documented in many previous studies, element analysis enabled separate activity areas to be distinguished, but the results could not be used to identify the specific activities pursued in the areas. A more qualitative identification of activity areas was possible through lipid analysis, however. The carbon chain distribution, studied for Average Chain Length (ACL), Carbon chain Diversity Index (CDI) and Carbon Preference Index (CPI), enabled a similar separation to be achieved as by element analysis, so that the same areas could be discerned in addition to the reference samples. The stable was distinguished by a substantial input of coprostanol and even more so by 24-ethylcoprostanol, indicating a faecal input from herbivores. Trace levels of these markers were also identified at the entrance, where the animals had passed through. The dwelling area, consisting of two adjacent rooms, could be identified by the sterol ratio (cholesterol/[stigmasterol + β-sitosterol + campesterol]). Lipids from an archaeological context have decayed further toward simpler compounds and become more difficult to identify. Some markers have however a better potential for survival. The results emphasize the importance of further studies on ethnoarchaeological material in order to recognize past activities by element analysis. Moreover, the combination of element and lipid analyses provided a tool that enabled all the separate areas to be identified and provided positive identification of the activities concerned in all areas except the smithy.     

山东省重化工业结构演进与区域经济持续发展

本文在对山东省近十多年工业发展资料分析的基础上,总结了山东省重化工业结构演进和地区工业结构特点,提出了加速工业化进程,推进山东经济持续发展的对策。