Geodynamically induced variations in the emission of CO2 gas at San Faustino (Central Apennines,Italy)

The Central Apennines are affected by frequent earthquakes of moderate magnitude that occur mainly within the upper part of the crust at depths of <15 km. A large number of cold gas emissions that are rich in CO₂ are also found in the region. One particular vent with a high rate of degassing was equipped with a sensor to measure flow rates, which were recorded for a number of different periods between 2005 and 2010. Factors that could affect potentially CO₂ flow rates include barometric pressure, atmospheric temperature, precipitation and local seismicity. Our analysis indicates that the periods of anomalous flow rate were related not to the environmental factors but probably to the deformative processes of the crust associated with the local seismicity. Local seismic events as expression of geodynamic processes occurred always before and during these anomalous gas flow periods. This correlation exists only for events that occurred eastwards of the gas emission site close to the Martana fault zone. We herein consider this correlation as indication for a continuous interaction between the field of static strain and the deep fluid pressure. An approximation of the fluid pressure transmission towards the gas emission site gives reasonable values of 1–10 m² sec^?1. To make comparisons with the long‐term effects of the static strain, we also recorded the short‐term effects of the dynamic release of strain induced by the series of strong earthquakes that took place in L’Aquila in 2009. We detected a significant anomalous flow rate that occurred at the same time as this seismic sequence, during which widespread degassing was induced around the focal zone.     

Investigation of coupled hydraulic–geomechanical processes at the KTB site: pressure‐dependent characteristics of a long‐term pump test and elastic interpretation using a geomechanical facies model

The German Continental Deep Drilling Program comprising a pilot borehole down to 4000 m and a main borehole down to 9101 m in southeast Germany (KTB) is continuing to provide a unique opportunity for the identification of important factors and processes in deep‐seated fluid and energy transfer. In situ stress conditions significantly impact flow, transport and exchange characteristics of fracture networks that dominate the permeability of crystalline reservoir rocks. In this paper, several scales of information are combined to present a fully three‐dimensional hydraulic finite element model of the principal KTB fault zones, and linked to a geomechanical model describing the alteration of the hydraulic parameters with stress changes caused by fluid extraction. The concept of geomechanical facies is introduced to define and characterize architectural elements in the subsurface system. Evaluation of a long‐term pump test in the KTB pilot hole, June 2002–July 2003, coupled with a geomechanical model gives an insight into some of the elastic and nonelastic processes controlling hydraulic transport in the basement rocks. Trends in the decline of the permeability and the degree of storage in the system could only partially be explained by elastic processes, clearly indicating the importance of nonelastic processes. A number of inelastic processes are suggested as areas for further research.     

The Study of Local Public Economies: Multi‐organizational,Multi‐level Institutional Analysis and Development

One important extension of the IAD framework has been to the study of local public economies. These are multi‐organizational, multi‐level arrangements defined as the set of governmental jurisdictions, public and nonprofit agencies, and private firms that interact in various patterns to provide and produce public goods and services within a specific locality or region. Commonly, the localities or regions studied from this perspective have been U.S. metropolitan areas, often defined as a central city and its surrounding or adjoining county. Localities can be delineated, however, on various terms, and in the IAD framework, it is the geo‐physical nature of a locality that, in substantial part, drives the analysis. One of the strengths of the approach is its capacity to explain local variations in public organization as a function of the geo‐physical diversity of localities, while at the same time developing empirical generalizations and normative principles that apply across diverse regions. What, for example, might the organization and governance of a complex metropolitan area have in common with the organization and governance of a complex protected area, such as the greater Yellowstone eco‐region or the Adirondack Park? Construing both sorts of regions as local public economies can enhance our overall understanding of public organization at the same time that it permits a more nuanced understanding of diverse localities. Such work contributes to the ongoing IAD project of “understanding institutional diversity.”     

The Supply of Glass at Portus Ilicitanus (Alicante,Spain): A Meta‐Analysis of HIMT Glasses

Portus Ilicitanus (Picola, Alicante) was the main sea harbour of the Roman Colonia Iulia Ilici Augusta and as such played a crucial role in the supply of fundamental commodities to the Iberian Peninsula. Excavations yielded large quantities of glass in fourth‐ and early fifth‐century contexts. Elemental analysis of 60 samples by laser ablation – inductively coupled plasma – mass spectrometry (LA–ICP–MS) confirmed that the glasses were imported from the Eastern Mediterranean. A majority of the glasses correspond to the HIMTa primary production group, which originates from Egypt. The statistical evaluation of published data of 589 HIMT glasses further revealed differential distribution patterns of the HIMTa and HIMTb subtypes between the Eastern and Western Mediterranean, suggesting chronological trends that are linked to wider geopolitical changes. This demonstrates the need for systematic large‐scale approaches to identify supply patterns and possible factors underlying geographical differences and/or chronological developments.     

New radiometric dating of water management features at the prehistoric Purrón Dam Complex,Tehuacán Valley,Puebla, México

Recent investigations at the prehistoric Purrón Dam Complex in the Tehuacán Valley of southern Puebla, México applied radiometric dating to more securely date the complex. Ceramic-based dating in the 1960′s placed the Dam's origin to the Formative Period. While Formative Period origins are widely accepted, the chronology lacks resolution and direct dates. Samples from impounded sediments behind the dam and from prehistoric canal fill were dated through Optically Stimulated Luminescence (OSL) as well as both standard ¹⁴C and accelerated mass spectrometry (AMS) assays. These samples directly date the functioning of the water management features within the complex. The results confirm the Formative Period origins of the Purrón Dam, and offer new insights into the construction and functioning of the dam and irrigation system.     

Investigating Activity Patterns In Prehispanic Plazas: Weak Acid‐Extraction ICP–AES Analysis of Anthrosols at Classic Period El Coyote,Northwestern Honduras

Weak acid‐extraction ICP–AES analysis was performed to obtain multi‐elemental characterizations of anthropogenic sediments from plaza spaces that no longer contain artefacts and adjacent trash deposits at the prehispanic site of El Coyote in northwestern Honduras. Multivariate quantitative assessments of the anthrosol chemical data, along with associated inventories of midden materials, are examined to derive signatures for activity areas and refuse dumps that can be linked across portions of the site. The findings of this study permit the reconstruction of activity patterns in the site's main plaza and in its environs. This has important implications for understanding the relationship among ritual practice, craft production and political economy during the Late and Terminal Classic periods, c. ad 600–1000.     

The Preservation of Invertebrates in 16th‐Century Cesspits at St Saviourgate,York*

The taphonomy of invertebrates from 16th‐century cesspits at St Saviourgate, York, was investigated. Earthworms, fly larvae and puparia are preserved through replication in calcium phosphate, a process facilitated by acidic cesspit pore water and by the presence of abundant organic matter, bones and shells. Features preserved by mineralization include muscles, blood vessels and setae. Non‐mineralized invertebrate remains include puparia and beetles. Py–GC/MS (flash pyrolysis–gas chromatography/mass spectrometry) revealed a very high level of preservation of structural biomolecules, with all the protein and chitin markers that are evident in the living forms still being detectable in the divalent remains.     

Changes in sub‐water table fluid flow at the end of the Proterozoic and its implications for gas pulsars and MVT lead–zinc deposits

A fundamental change in the nature of sub‐water table fluid flow occurred at roughly the Proterozoic–Phanerozoic boundary when organic matter began to be buried in sufficient quantities that nonaqueous fluids could occupy a significant fraction of the pore space. This allowed the formation of remarkably durable capillary seals that could trap gas in large portions (hundreds of kilometers) of a basin for hundreds of millions of years. Gas loss from these gas zones can be highly dynamic, especially during gas generation. Under the right circumstances, hundreds of cubic kilometers of gas can be rapidly discharged into adjacent permeable aquifers. In Pennsylvanian/Permian time, the Arkoma Basin may have repeatedly discharged such volumes of gas into the very permeable Cambrian sandstone and karstic carbonate aquifers of the mid‐continent of the United States. This could have displaced brines rapidly enough to form the Mississippi Valley‐type (MVT) lead–zinc deposits of this age that are associated with the Arkoma Basin, heating them only briefly as required by maturity indicators. Sea level rise accompanying the melting of Permian continental glaciers may have triggered the gas expulsion events. This radically new mechanism for the formation of MVT deposits is just one example of the nonlinear dynamics of gas accumulations that are possible since Late Proterozoic time.     

Mining Archaeology and Micro‐Raman Analysis Associated with ESEM‐EDX: Toward a Chrono‐Spatial Definition of Ore Consumption in a Pyrenean Medieval Workshop, 14th–16th Centuries

The rapid expansion of non‐ferrous metallurgy in the late Middle Ages (14th–15th centuries) enhanced ore demand, which was supported by mining intensification. Metallurgical workshops developed various supply strategies based on geological, political and economic constraints. This is particularly true for the Pyrenean multi‐metals workshop of Castel‐Minier (Ariège, France), where recent excavations unearthed an exceptional corpus of non‐ferrous ores. A specific analytical methodology combining micro‐Raman spectroscopy and environmental scanning electron microscopy with energy dispersive X‐ray (ESEM‐EDX) was set up to study these artefacts. This composite methodology permitted the fast characterization of both mineral and gangue as well as a discussion of their economic potential. Ores identified were compared with ancient mines in neighbouring mining districts in order to sketch a geography of the mineral resources available to medieval metallurgists. Moreover, a chrono‐stratigraphic study of ore distribution in Castel‐Minier revealed the supply strategies, technological choices as well as spatializing of copper and lead metallurgies.     

One of His Majesty's ‘Beste Kraffwells’: the wreck of an early carvel‐built ship at Franska Sternarna,Sweden

We report recent fieldwork on an early‐16th‐century wreck in the Stockholm archipelago, Sweden. The discovery not only provides new insights into early carvel shipbuilding and its adoption across northern Europe but manifests the changing role of ships and the nature of power and agency in the process of state formation at the dawn of the modern world. © 2012 The Authors     

Precipitation of lead–zinc ores in the Mississippi Valley‐type deposit at Trèves,Cévennes region of southern France

The Trèves zinc–lead deposit is one of several Mississippi Valley‐type (MVT) deposits in the Cévennes region of southern France. Fluid inclusion studies show that the ore was deposited at temperatures between approximately 80 and 150°C from a brine that derived its salinity mainly from the evaporation of seawater past halite saturation. Lead isotope studies suggest that the metals were extracted from local basement rocks. Sulfur isotope data and studies of organic matter indicate that the reduced sulfur in the ores was derived from the reduction of Mesozoic marine sulfate by thermochemical sulfate reduction or bacterially mediated processes at a different time or place from ore deposition. The large range of δ³⁴S values determined for the minerals in the deposit (12.2–19.2‰ for barite, 3.8–13.8‰ for sphalerite and galena, and 8.7 to ?21.2‰ for pyrite), are best explained by the mixing of fluids containing different sources of sulfur. Geochemical reaction path calculations, based on quantitative fluid inclusion data and constrained by field observations, were used to evaluate possible precipitation mechanisms. The most important precipitation mechanism was probably the mixing of fluids containing different metal and reduced sulfur contents. Cooling, dilution, and changes in pH of the ore fluid probably played a minor role in the precipitation of ores. The optimum results that produced the most metal sulfide deposition with the least amount of fluid was the mixing of a fluid containing low amounts of reduced sulfur with a sulfur‐rich, metal poor fluid. In this scenario, large amounts of sphalerite and galena are precipitated, together with smaller quantities of pyrite precipitated and dolomite dissolved. The relative amounts of metal precipitated and dolomite dissolved in this scenario agree with field observations that show only minor dolomite dissolution during ore deposition. The modeling results demonstrate the important control of the reduced sulfur concentration on the Zn and Pb transport capacity of the ore fluid and the volumes of fluid required to form the deposit. The studies of the Trèves ores provide insights into the ore‐forming processes of a typical MVT deposit in the Cévennes region. However, the extent to which these processes can be extrapolated to other MVT deposits in the Cévennes region is problematic. Nevertheless, the evidence for the extensive migration of fluids in the basement and sedimentary cover rocks in the Cévennes region suggests that the ore forming processes for the Trèves deposit must be considered equally viable possibilities for the numerous fault‐controlled and mineralogically similar MVT deposits in the Cévennes region.     

The geochemical evolution of very dilute CO2‐rich water in Chungcheong Province,Korea: processes and pathways

A geochemical study was carried out on the CO₂‐rich water occurring in granite areas of Chungcheong Province, Korea. In this area, very dilute and acidic CO₂‐rich waters [62–242 mg l^?1 in total dissolved solid (TDS), 4.0–5.3 in pH; group I) occur together with normal CO₂‐rich waters (317–988 mg l^?1 in TDS, 5.5–6.0 in pH; group II). The concentration levels and ages of group I water are similar to those of recently recharged and low‐mineralized groundwater (group III). Calculation of reaction pathways suggests that group I waters are produced by direct influx of CO₂ gas into group III type waters. When the groundwater is injected with CO₂, it develops the capacity to accept dissolved solids and it can evolve into water with very high solute concentrations. Whether the water is open or closed to the CO₂ gases becomes less important in controlling the reaction pathway of the CO₂‐rich groundwater when the initial pco ₂ is high. Our data show that most of the solutes are dissolved in the CO₂‐rich groundwater at pH > 5 where the weathering rates of silicates are very slow or independent of pH. Thus, groundwater age is likely more important in developing high solute concentrations in the CO₂‐rich groundwaters than accelerated weathering kinetics because of acidic pH caused by high pco ₂.     

Linking Land and Navy: archaeological investigations at the site of the Woolwich Royal Dockyard,south‐eastern England

This paper outlines the archaeological evidence found at the demolished Royal Naval Dockyard at Woolwich for the development and construction of dockyard structures of the 18th to early‐19th centuries. This is set within the framework provided by historic, documentary, map and historic‐model evidence. The results of earlier excavations at the same facility are also reviewed. The themes covered include; the interplay of ‘carpentry’ versus ‘shipwrightry’ in dockyard construction, aspects of naval timber‐supply and landscape, the recycling of ships' timbers, dockyard craft specialisation and changing relative sea‐levels. © 2011 Pre‐Construct Archaeology Limited     

First Insights into the Technique Used for Heat Treatment of Chert at the Solutrean Site of Laugerie‐Haute,France

The earliest evidence of flint and chert heat treatment was found in the ~21.5–17 ka old European Solutrean culture. The appearance of pyrotechnology as part of the production of stone tools has important implications for our understanding of Upper Palaeolithic technological evolution and the specific adaptations during the last glacial maximum in Europe. However, the techniques and procedures used to heat‐treat rocks during the Solutrean remain poorly understood. No direct archaeological evidence has so far been found and the most promising approach is to understand these techniques by determining the parameters with which flint and chert were heated at that time. In this study, we investigate the heating temperature of 44 heat‐treated laurel‐leaf points from Laugerie‐Haute, using a non‐destructive technique based on infrared spectroscopy. Our results document that most of the artefacts were heated to a narrow interval of temperatures between 250 °C and 300 °C. This indicates a standardized technique that allowed to created similar conditions during successive heating cycles. The implications of these results for our understanding of the technical complexity during the Solutrean must be discussed in the light of different heating techniques used at different places and periods.     

‘The Party Hack,and Tool of the British Government’: T.P. O'Connor,America and Irish Party Resilience at the February 1918 South Armagh By‐Election

The common view of Irish electoral politics for the 1916 to 1918 period is one of major decline for the traditional nationalist representatives, the Irish Parliamentary Party (IPP), and the meteoric rise of the newly reconstituted Sinn Féin party; culminating in the latter's overwhelming victory at the December 1918 general election. By examining the February 1918 South Armagh by‐election campaign, this article argues that the Irish Parliamentary Party, which won the contest, was much more resilient than is often acknowledged. Through detailed analysis of election pamphlets, newspaper articles, private correspondence and committee minutes, it considers the significance of the grass‐roots strength of both in the form of their local organisations, the role of the Roman catholic church, and the election strategies of the two parties; in particular Sinn Féin's vilification of the IPP member, T.P. O'Connor, who was in America at the time of the contest.