Carboniferous Limestone Research Articles

Black "marble" in the Polish architecture - characteristics and possibility of its provenance determination: the case of the Dębnik limestone

Black limestone, also known as black marble, was widely used in the Polish small-scale architecture and art of the 17th and 18th centuries. Besides the Devonian limestone from Debnik near Krakow, also popular were the Netherlandish (Wallonian), Devonian to Carboniferous limestones from the Meuse River and Schelde River valleys. This paper deals with the possibility of identifying the rocks imported to Poland. Macroscopic similarities between the Netherlandish rocks and some Debnik limestones have been highlighted for the oldest Carmelite quarry in Debnik, exploiting the best stones. The analyses include: optical microscopy, scanning electron microscopy with EDS, X-ray diffraction, X-ray fluorescence and isotope ratio mass spectrometry (13 C and 18 O stable isotopes). Carboniferous limestones from Netherlands can be identified within and distinguished from the Debnik limestone in the macroscopic observations. Differences, depending on the varieties, are associated primarily with the presence of white calcite fragments of fossils, calcite veins intersecting the rock in all directions or hardness of the limestones. Deeply black Devonian limestones from Wallonia and Debnik without macrofossils and calcite veins differ in microscopic observations considering their texture, type of microfossils and inventory of non-carbonate components. The characteristic graying and whitening of the black limestones has also been discussed as a possible feature of rock provenance.

3D microstructure characterisation of tight reservoir rocks and effective recoverable reserve estimation

A data-constrained modelling (DCM) approach has been developed at CSIRO, which enables 3D characterisation of pores and mineral phase distributions using quantitative multi-energy synchrotron CT. For a tight reservoir, such as a carbonate limestone or a shale rock, DCM can generate microscopic partial volume distributions of materials and pores which are the effects of the fine length scales below X-ray CT resolution. Using this information, a quantitative relation between recoverable reserve and pore-throat size can be established for a rock sample. The technique can also be used for characterisation of other unconventional reservoir rocks.

Regional weather and climates of the British Isles – Part 6: Ireland

On 4 June 1944, the lighthouse keeper at Blacksod Bay on the far northwest of County Mayo relayed his usual weather observations to Dublin and on to London. On receiving the report from Blacksod, the Allied commanders decided to postpone for a day Operation Overlord that was to launch the invasion of German-occupied western Europe: a wise move since the Force 7 winds and heavy rain experienced in the Channel the next day could have seriously compromised the success of the operation. Sitting astride the main storm tracks, Ireland has always provided an early warning system, particularly for Britain, of forthcoming extreme events originating over the Atlantic, as well as a shield which lessens their severity. Ireland possesses a rich and varied climate mosaic, a product of its distinctive topography and geography, which interact with airstreams to produce a complex spatial arrangement of climates not often appreciated beyond its shores. In Victorian times the geomorphology of Ireland was taught by an analogy to an apple pie – the hard crusty bits around the edges enclosing a soft centre. This geological legacy of hard Caledonian and Armorican rocks around the perimeter and soft Carboniferous limestones in the centre creates an unusual topographic arrangement (Figure 1). In the west, with only a few breaks in the mountainous edge at Sligo Bay, Galway Bay and the Shannon Estuary that allow easier access for maritime air masses, there are some surprisingly sheltered pockets. The south and north coasts also have their mountain bulwarks in the Cork–Kerry and Donegal mountains and some protection is even afforded to the east coast by the Antrim Plateau and the Wicklow Mountains. A coast-versus-interior geography is, therefore, the chief characteristic of the Irish climate, so that the climate of the Central Plain has more in common with lowland England than with its Celtic neighbours of Wales and Scotland. The legacy of past weather observations

Early Carboniferous trilobite remains from limestones of the Dębnik Anticline, southern Poland

The presence of proetid trilobites remnants is reported for the first time from the early Carboniferous limestones of the Debnik Anticline outcropped in the Raclawka valley, the eastern part of the Upper Silesian Block (southern part of the Cracow Upland). Disintegrated exoskeletons of trilobites have been found in thin sections of fine-grained, peloidal wackstones and packstones. These rocks contain also foraminifers which indicate the Early Tournaisian age of this founding.

Geology, mineralogy, geochemistry, and depositional environment of a Late Miocene/Pliocene fluviolacustrine succession, Cappadocian Volcanic Province, central Anatolia, Turkey

This paper investigates the mineralogy, geochemistry, and depositional environment of Late Miocene/Pliocene fluviolacustrine deposits, including multiple ignimbrite levels and andesitic and basaltic lavas, within the Cappadocian Volcanic Province (CVP) of central Anatolia, Turkey. Palaeosols and calcretes formed within these terrestrial sedimentary rocks under near-surface or surface conditions. The palaeosols are composed predominantly of smectite ± illite with feldspar, quartz, calcite, opal-CT, and amphibole, and the calcretes mainly of calcite with minor feldspar, quartz, and accessory smectite ± palygorskite. The palygorskite occurs on and between the calcite crystals in the calcretes and at the edges of smectite flakes within the palaeosols, indicating an in situ formation from evaporated alkaline water rich in Si and Mg and poor in Al under arid or seasonally arid climatic conditions. In the palaeosols and calcretes, negative Ba, Nb, Ce, Sr, and Ti anomalies and an enrichment of light rare earth elements relative to medium rare earth elements and heavy rare earth elements, with a distinct negative Eu anomaly, likely reflect the alteration of feldspars and amphiboles in the ignimbrite. The alteration of the ignimbrites caused the depletion of SiO2, Al2O3+Fe2O3, TiO2, and K2O through the precipitation of smectite ± illite in the palaeosols and CaO in the form of calcite in the calcretes. The delta18O values of the calcretes and limestones range from –8.71‰ to –10.71‰, which are mainly related to the involvement of high-elevation meteoric water, whereas the delta13C values for the same rocks vary between –1.97‰ and 5.71‰. The positive delta13C values for the limestones reflect calcite precipitation in isotopic equilibrium with meteoric water in a lake. The slightly negative delta13C values of the lacustrine limestone carbonates may indicate precipitation from a relatively thick water column and an inflow of surface or groundwater through the ignimbrites with high Ba/Sr values. Conversely, the calcrete delta13C values (3.0‰ to 4.97‰) may suggest a pedogenic origin with low plant respiration rates and a predominance of C4 plants. Based on stable oxygen isotope values from the lake sediments and calcretes, this study suggests that the global warming trend that followed the Late Miocene continued into the Pliocene within the CVP.

Groundwater interaction assessment based on the large-scale mapping of geological and hydrogeological conditions in Moscow

Assessing the interaction between aquifers is crucial for estimating the extent of protection of the aquifer in Carboniferous limestone (which is the main source of potable water supply to Moscow area) against contaminants penetrating from the overlying aquifers. The presented approach to assessing groundwater interaction and protection is based on large-scale mapping of the geological and hydrogeological conditions in Moscow. The obtained results may be used for solving the problem of groundwater protection against contamination, as well as for planning the engineering activities in the city.

Measurement of rates of surface lowering of limestone in the southern Pennines: an example in the Wye catchment, Derbyshire, UK

Measurement of the differential denudation between chert and limestone in a Carboniferous limestone sequence that was cut during excavations for a railway tunnel (in 1865) has provided a means of assessing limestone dissolution rates in a valley side setting in the southern Pennines over the last ∼150 years. Dissolution rates of 0.031 mm/annum have been determined. This rate falls within the range of previously determined limestone dissolution rates in the UK, which have been described in the context of different methods of measurement and the difference in denudations rates over time.

The microstructural properties and deformation environments of the Kugarchi folded complex, Southern Urals

The Kugarchi folded complex is located on the western slope of the Southern Urals; it is a region of complex disharmonic folding in the Lower Carboniferous limestones. We revealed and studied two systems of mineral veins and accompanying veinlets in limestones. The microstructural analysis was used to recognize several deformation stages and orientations of the principal strain directions. This folded complex is interpreted to have formed under conditions close to uniaxial compression accompanied by a progressive change in the extensional strain direction from vertical to horizontal.

Castleton, Derbyshire, UK

The area around Castleton in the English county of Derbyshire has extensive outcrops of Carboniferous Limestone, showing complex sedimentary facies changes as well as interleaved extrusive basaltic volcanic rocks. Overlying these are the lower parts of the Millstone Grit, ranging from marine shales through a variety of deltaic sandstones. The limestones are hosts to hydrothermal mineral deposits, with veins containing galena, fluorspar, baryte and calcite. A unique variety of fluorspar is Blue John, mined for ornamental purposes since the mid‐eighteenth century. Landscape features include a massive landslip, dry valleys, loess, dolines, scree slopes and various karstic landforms. A complex hydrological system encompasses numerous caves, of which four are open to visitors.

Noble gas, CFC and other geochemical evidence for the age and origin of the Bath thermal waters, UK

The city of Bath is a World Heritage site and its thermal waters, the Roman Baths and new spa development rely on undisturbed flow of the springs (45°C). The current investigations provide an improved understanding of the residence times and flow regime as basis for the source protection. Trace gas indicators including the noble gases (helium, neon, argon, krypton and xenon) and chlorofluorocarbons (CFCs), together with a more comprehensive examination of chemical and stable isotope tracers are used to characterise the sources of the thermal water and any modern components. It is shown conclusively by the use of 39Ar that the bulk of the thermal water has been in circulation within the Carboniferous Limestone for at least 1000years. Other stable isotope and noble gas measurements confirm previous findings and strongly suggest recharge within the Holocene time period (i.e. the last 12 kyr). Measurements of dissolved 85Kr and chlorofluorocarbons constrain previous indications from tritium that a small proportion (<5%) of the thermal water originates from modern leakage into the spring pipe passing through Mesozoic valley fill underlying Bath. This introduces small amounts of O2 into the system, resulting in the Fe precipitation seen in the King’s Spring. Silica geothermometry indicates that the water is likely to have reached a maximum temperature of between 69–99°C, indicating a most probable maximum circulation depth of ∼3km, which is in line with recent geological models. The rise to the surface of the water is sufficiently indirect that a temperature loss of >20°C is incurred. There is overwhelming evidence that the water has evolved within the Carboniferous Limestone formation, although the chemistry alone cannot pinpoint the geometry of the recharge area or circulation route. For a likely residence time of 1–12kyr, volumetric calculations imply a large storage volume and circulation pathway if typical porosities of the limestone at depth are used, indicating that much of the Bath-Bristol basin must be involved in the water storage.

Geothermal energy in sedimentary basins in the UK

Deep onshore Mesozoic basins have favourable geothermal aquifers at depth comprising basal Permo-Triassic sandstones. The principal basins are the Wessex and Worcester (southern England), Cheshire (northwest England), Eastern England, Larne and Lough Neagh (Northern Ireland). Measured temperatures are up to 80 °C and could reach 100 °C in the deepest parts of some of the basins. Porosity and permeability data from depth are limited, but values high enough to allow adequate yields have been measured in many of the basins. Productive sandstones vary from a few tens of metres to hundreds of metres thick resulting in productive transmissivities. The estimated heat in place (Inferred Geothermal Resource) has been calculated as 201 × 1018 to 328 × 1018 J. New heat demand maps illustrate that many of the centres of high heat use are coincident with Upper Palaeozoic basins. Within the Carboniferous and Devonian there are thick sequences of deeply buried arenaceous deposits. Some productive local aquifers occur at shallow depth, but most depend on fissure flow that is anticipated to diminish rapidly with depth. The exception may be the Carboniferous Limestone where warm springs and a pronounced thermal anomaly in Eastern England demonstrate groundwater flow at depth, possibly along pathways of many kilometers.

In situ monitoring of karst springs in Wallonia (southern Belgium)

The implementation of the Water Framework Directive, as well as the forthcoming entry into force of other European water policies focusing on water resources, require a thorough reorganization of groundwater resources monitoring in most European countries. In Wallonia, monitoring programs were initiated in 2005 to control the quantitative and chemical statuses of groundwater bodies, as well as the effectiveness of management plans aimed at achieving environmental objectives. In karst aquifers, springs are preferential monitoring targets even if, as a result of the high heterogeneity of this type of aquifer, the interpretation of time series and spatial data remains a challenge. Since 2006, a “springs” monitoring network has been progressively set up in the southern part of Belgium. Currently, in situ measurements of discharge, temperature, conductivity, turbidity and fluorescence of water are conducted at nine karstic outlets in the Devonian and the Carboniferous limestone aquifers of Wallonia. The main objective of this ongoing research is to evaluate the suitability and the robustness of such standard measurements to discriminate anthropogenic impacts from natural variations, at both short- and long-term scales. Discharge and temperature data revealed being useful in the assessment of regional hydro-climatic trends. Groundwater proved to be a better natural filter for the assessment of long-term climatic changes than mathematical filtering of noisy surface signals. Investigations of such data at a European scale could therefore give additional insight into the impacts of climate change on groundwater resources. Conductivity, turbidity and fluorescence data characterize the particulate, mineral and organic health of water and a better understanding of their natural dynamics could help in the early detection of anthropogenic deviations. However, the current reproducibility of these measurements is too low to ascertain observed trends and fluctuations, and further research is still needed.

Mesolithic and Neolithic Human Remains from Foxhole Cave, Gower, South Wales

This paper presents an overview of the results of two brief excavation seasons (2008 and 2010) at Foxhole Cave, Gower, south Wales, placing them into the wider context of mid-Holocene Britain. No prehistoric pottery was found and the few pieces of worked flint recovered are diagnostic of the Mesolithic period. Typically for the Carboniferous limestone caves of Gower, bone was well preserved, however, and though much of the material in the heavily disturbed upper metre or so of the deposits was modern sheep and rabbit, scattered fragments representing the remains of at least six humans were also recovered, of which two have been directly radiocarbon-dated using accelerator mass spectrometry (AMS 14C) to the Late Mesolithic and two to the earlier Neolithic (the remaining two providing Romano-British and medieval dates). Their associated stable carbon and nitrogen isotope values indicate a significant difference in diet between the two periods (contrary to the results from an earlier excavation in 1997), with marine foods contributing around half of the protein for the Mesolithic individuals and little or none for the Neolithic individuals. The new results are consistent with those from Caldey Island, Pembrokeshire, some 30km to the west. The floor of the cave has still not been reached at around 2m depth; limited investigation of the lowermost levels has yielded a Pleistocene fauna (including reindeer, aurochs or bison and collared lemming) with dates back to approx 33,500 cal bc, though with no definite evidence for human activity so far. A small, dark-stained fragment of human cranium was recovered from what may be pre-Holocene levels, but this failed to produce sufficient collagen for dating. In addition to a marked dietary shift, the combined stable isotope and dating programme provides further support for an equally striking temporal gap of some two millennia between the Mesolithic and Neolithic use of caves for burial.

Flow Characterization in the Santee Cave System in the Chapel Branch Creek Watershed, Upper Coastal Plain of South Carolina, USA

Karst watersheds possess both diffuse and conduit flow and varying degrees of connectivity between surface and groundwater over spatial scales that result in complex hydrology and contaminant transport processes. The flow regime and surface- groundwater connection must be properly identified and characterized to improve management in karst watersheds with impaired water bodies, such as the Chapel Branch Creek (CBC), South Carolina watershed, which has a long-term sampling station presently listed on an EPA 303(d) list for phosphorous, pH, and nitrogen. Water from the carbonate limestone aquifer of the Santee Cave system and spring seeps in the CBC watershed were monitored to characterize dominant flow type and surface-groundwater connection by measuring dissolved calcium and magnesium, total suspended solids, volatile suspended solids, alkalinity, pH, specific conductance, and stable isotopes (d 18 O, d 2 H). These measurements indicated that the conduit flow to Santee Cave spring was recharged predominantly from diffuse flow, with a slow response of surface water infiltration to the conduit. Qualitative dye traces and stage elevation at Santee Cave spring and the adjacent Lake Marion (equal to the elevation of the flooded portion of CBC) also indicated a relation between fluctuating base level of the CBC reservoir-like embayment and elevation of the Santee Limestone karst aquifer at the spring. Methods described herein to characterize the flow type and surface-groundwater connection in the Santee Cave system can be applied not only to watershed management in the Chapel Branch Creek watershed, but also to the greater region where this carbonate limestone aquifer exists.

Insights into the origin of the thermal springs of Bath and Bristol, England, from geophysical data

The thermal springs of Bath, England, produce 1.25 Ml day −1 of water at 46.5 °C. The spring at Hotwells, Bristol, England, 15 km to the west, is estimated to produce between 0.17 and 0.39 Ml day −1 of water at a temperature between 22.8 and 24.4 °C. Published research suggests that the waters originate in the Mendip Hills, SW of Bath and Bristol, and are heated by geothermal energy within the Carboniferous Limestone basin (‘The Mendips Model’). The exact paths of the waters to the springs have not been established. We interpreted seismic reflection data for the urban district of Bath and for the Radstock Basin to the south of Bath. By combining the geophysical interpretations with published geological data we have established a potential route through the Carboniferous Limestone reaching sufficient depths for the waters to attain the required temperatures. We imaged a steeply dipping, fractured region of Carboniferous Limestone coincident with the valley of the River Avon and propose that this is the feature by which the thermal waters can rise rapidly to the surface, providing an explanation for the existence of these unique springs. We have incorporated these new aspects of the Mendip Model into the ‘Mendip–Avon Fracture Zone Model’.

Geological controls on radon potential in England

Radon exposure is a chronic and serious geohazard but with the correct knowledge of its distribution provided by an accurate radon potential map, this risk to human health can be reduced through well directed radon testing programmes and building control regulations. The radon potential map presented here, produced by mapping radon concentrations in homes, grouped by underlying geology, provides the most detailed and accurate assessment of radon in England. Bedrock and superficial geology associated with the most radon prone areas are investigated using the joint HPA-BGS radon potential dataset, geological information and, where available, soil geochemistry, airborne radiometric or laboratory analysis. Some of the geological units associated with high radon potential are well known, such as the granite intrusions in south west England, the Carboniferous limestones of Derbyshire and the Jurassic ironstones in Northamptonshire. This study provides a more comprehensive description of the main bedrock geological units associated with intermediate to high radon potential in England including: granites and associated uranium mineralisation in south west England; Devonian, Carboniferous, Permian and Jurassic limestones and dolomites; Devonian, Carboniferous, Jurassic and Cretaceous sandstones; Silurian, Devonian, Lower Carboniferous and Jurassic mudstones; Jurassic ironstones; and some Triassic breccias and conglomerates. Uranium in soil is elevated over many known radon-prone areas but also reflects the accumulation of U in organic-rich soil and peat. Near surface weathering, bedrock fracturing and former working of the ironstones in the English Midlands are all implicated in increased radon potential on these geological units.

Groundwater Resources Modeling: A Case Study from the U.K.

As populations grow, climates change, and water resources (and budgets) dwindle, well-documented, wellcoordinated, and well-maintained groundwater management tools are needed more than ever. This book (Shepley et al. 2012), a collection of papers written specifically for this volume, provides not only case studies of individual groundwater modeling efforts, but also an important case study of an overall effort to model a nation’s aquifers. I read this book with great personal interest because I have been involved with a similar modeling program in Texas. (Texas is not a nation, but it used to be!) This collection of papers documents a national program administered by the United Kingdom’s Environment Agency between 1998 and 2009 to develop groundwater flow models of England’s and Wales’ primary bedrock aquifers. While most nonnatives will be aware of the internationally famous Chalk Aquifer, the book also discusses the Permo-Triassic Sandstone Aquifer, the Carboniferous Limestone Aquifer, and the Scottish alluvial aquifers, among others. The editors were closely involved in the national effort; therefore, they were well-positioned to coordinate and deliver a thorough and well-documented product. Broadly, the papers in the book fall into one of three categories: (1) organization and execution of the national modeling effort; (2) descriptions of the modeling efforts; and (3) discussions of conceptual model issues, methodologies, and use of the models. After a foreword by Mary P. Anderson (who also served as a reviewer of the volume), the first five papers focus on the organization and execution of the modeling program, including the history of modeling in the United Kingdom, the background of the national modeling program, the management of the program and its standards, how stakeholders were included in the process, and how final models have been served to stakeholders and others. Eight of the remaining 17 papers are primarily focused on descriptions of specific regional modeling efforts, with the other nine papers focused on conceptual model issues, methodologies, and use of the models. Topics include estimating recharge, using modeling to better understand groundwater flow, and developing and

Where are all the crinoids? An enigma of the Lower Carboniferous (Mississippian) White Peak of midland England

A glut of fossil crinoids does not lead to a succession being recognised as rich in crinoids. Crinoid palaeontology relies on cups, crowns and complete specimens, not fragments. The Carboniferous Limestone of the White Peak is rich in crinoid fragments, but depauperate in named crinoids. Something needs to be done.

Occurrence of molybdenum in British surface water and groundwater: Distributions, controls and implications for water supply

Data for Mo in British surface water and groundwater collated from a number of databases show that concentrations are in most cases low, of the order of 2μg/L or less. However, variability is large and sporadic high values are found in both streamwaters and groundwaters. Data for some 11,600 British streamwater samples indicate a 10–90th percentile range of 0.08–2.44μg/L with a median of 0.57μg/L and maximum observation of 230μg/L. High values tend to be from streams on clay-rich formations and sulphide-mineralised bedrock and streams affected by localised urban and industrial contamination. Monitored lowland river waters also typically have median concentrations <1μg/L although higher values are present in a number of urban/industrialised English rivers. Highest observed concentrations (median 20μg/L), occur under low-flow conditions in a river system from an urban, industrial area of NE England and are likely the products of industrial contamination and mine drainage. Concentrations in 96 upland lakewater samples from NW England are universally 0.1μg/L or less. Data for 1735 groundwater samples from across Britain have a 10–90th percentile range for Mo of 0.035–1.80μg/L with a median of 0.20μg/L and maximum observation of 89μg/L. Relatively high values derive from some Lower Cretaceous greensand, Carboniferous limestone and mudstone (Coal Measures) aquifers, particularly under anaerobic conditions. Release from Fe oxides and possibly Mn oxides by reductive dissolution is a likely mechanism for the concentrations. Under more rarely observed sulphate-reducing conditions in British aquifers, concentrations of Mo diminish, likely due to sequestration by precipitating sulphide minerals. The observed ranges in aqueous samples indicate that most water sources in Britain have Mo concentrations more than an order of magnitude below the WHO health-based value for Mo in drinking water (70μg/L). Such sources are unlikely to pose a risk to drinking water from the current WHO guidance, provided those impacted locally by mining or other industrial contamination are avoided.

Mineralogy, geochemistry, and genesis of lateritic bauxite deposits in the Wuchuan–Zheng'an–Daozhen area, Northern Guizhou Province, China

The lateritic bauxite deposits in the Wuchuan–Zheng'an–Daozhen area, Northern Guizhou Province, are hosted by the Liangshan Formation which unconformably overlies the Lower–Middle Silurian mud-shale and the Upper Carboniferous limestone and underlies the Middle Permian limestone. From the bottom upward, the deposits are generally composed of brick-red, yellow-brown, and gray bauxite horizons. Diaspore, boehmite, kaolinite, smectite and hematite are the major mineral components in the bauxite ores with small amounts of gibbsite, illite, goethite, pyrite, anatase, zircon, quartz and feldspar. The textural features of ores suggest that the bauxite has an authigenic origin but locally underwent transportation and re-deposition. Geochemical investigations indicate that the immobile elements like Al, Ti, Zr, Cr, Hf, Nb, Ta and Th were obviously enriched during bauxitization. Factors such as the type of parent rock, pH variation in weathering solutions, adsorption processes, groundwater chemical characteristics, Fe concentration variation in the weathering profiles, leaching degree of minerals, and geochemistry of elements have played a significant role in the distribution of trace and rare earth elements during weathering of the lateritic bauxite. The bauxites may have a close genetic relationship with the Hanjiadian mud shale and the Huanglong limestone in view of their similar chondrite-normalized REE patterns, Zr/Hf and Nb/Ta ratios. However, field observations and geochemical data suggest that the precursors of bauxites are complex and the main components of precursors are basic igneous rocks possibly from the Neoproterozoic basic igneous rocks and the Mesoproterozoic basic–ultrabasic intrusions in the Yangtze Block.