Underground Deposits Research Articles

Shale Oil and Gas Revolution: Why Nigeria Must Transform and Sustain the Agro Economy

The shale boom is on course to make the U.S. the world's largest oil producer by 2017.Dependence on OPEC's crude is slipping as the U.S. and Canada unlock unconventional oil supplies from deep underground shale deposits with new drilling techniques- the fracking or hydraulic fracturing. The Nigerian economy with 80% dependency on crude is going to bear the drastic burden. Demand for the Nigerian oil is declining with sizable impact on the economy that solely depends on the mono-product. To contain the impact, agricultural production remains a vital sector to take the hold. The paper while describing the U.S. shale oil boom, explores the agricultural transformation and its subsequent contribution to the gross domestic product (GDP), as alternative to developing and sustaining the economy. It further outlined public and private investments in agricultural knowledge, science and technology, and effective decision-making as crucial steps for the nation's economic development in less demand of oil.

Delimitation of the use of ploughs and cutter drums in medium to small seam thicknesses with the aid of face simulations

AbstractThe article “Software development as the driving force for automation in the raw materials and mining sector” deals with the basic development of technical engineering software in the raw materials and mining sector at the DMT company. Longwall mining simulation has been created as a special field in the DMT software. This software is designed for calculation and optimisation of different face extraction technologies.Current studies predict a sharply increasing global demand for energy in future years. The highest demand for raw materials for energy generation is forecast in particular for future markets such as China, India and Russia.Despite the worldwide efforts to observe climate aims coal as a conventional energy raw material will continue to play a major role. Consequently there is already evidence of an intensified trend towards development of new coal deposits. If can be stated that there is a big future in deep mines and the seams with medium and small thicknesses will attract increasing attention.DMT has based its portfolio on these developments and offers complete planning for the working of coal deposits in deep mines. This planning starts with the modelling of the underground deposit on the basis of core samples and drilling planning data from exploratory drilling and seismic surveys. The specific geological properties of the actual deposit can be seen with the aid of these deposit models (Fig. 1).

The importance of salt mines for mining towns

Salt mining is one of the oldest industrial areas of human activity. Composure and evolution of rock salt mining methods were in the past an important factor of the development and prosperity of many European salt cities, including Wieliczka and Bochnia. Studies of Polish and foreign salt cities showed that urban space and underground mine workings can interact to varying degrees, often creating interdependent systems, both in economic and visually-compositional terms. At the same time, in the face of a global collapse of the salt mining industry, you can see the process of liquidation of underground salt mine, also a number of historical sites. The specificity of the salt mine also tends to post-industrial use of these facilities for new features. In this matter, the dominant course of action is to build underground tourist routes and sanatoriums, creation places of a religious cult, art, entertainment, sports, science and education and other forms of public services. At the same time, salt excavations are an attractive area for the location less accessible facilities, such as laboratories, and most of all underground deposits. Analysis of different salt mining centres leads to the conclusion that all mentioned forms of redevelopment can be cost-effective, however, to ensure the sustainable development of the salt mining centres is important to: fully preserve the existing values, represented by both the excavation underground spaces as well as different parts of the surface mining infrastructure expose and provide access to protected values for the broad group of users; maintain the authentic character of mine (excavation and ground facilities) in its reconstruction and adaptation to modern needs It seems that the inclusion of these conditions gives a real opportunity to preserve and even enhance the attractiveness of disused salt mines and use them in the current development of the salt cities.

The Future of Fracking: New Rules Target Air Emissions for Cleaner Natural Gas Production

Natural gas is lauded as a cleaner-burning fuel than either coal or oil, but getting the fuel out of the ground can be a dirty process, especially given the widespread adoption of the technology known as hydraulic fracturing (“fracking”). Concerns about toxic air emissions from previously unregulated fracking sites led to the U.S. Environmental Protection Agency (EPA) announcement on 18 April 2012 of new and updated air pollution regulations for these facilities and certain other elements of oil and natural gas production and transmission.1 Compliance with the new regulations is expected to result in major reductions in emissions of methane and volatile organic compounds (VOCs), particularly from new fracked natural gas wells. The rules were a hot topic nationally, drawing more than 156,000 comments after the proposed version was released in mid-2011. Under the final rules, companies have until January 2015 to fully phase in the control measures needed; by comparison, the initial proposal called for a 60-day phase-in for many major requirements. The EPA says about half of all new wells already use the equipment needed to capture the targeted emissions.2 A hydraulic fracturing natural gas drilling rig on the eastern Colorado plains. In 2009 there were more than 38,000 natural gas wells in the state. Many environmental groups consider the new regulations an improvement over the existing situation, but they tend to be disappointed much more wasn’t done. “This is quite a milestone,” says Jeremy Nichols, Climate and Energy Program director for the advocacy group WildEarth Guardians, one of two groups that filed suit against the EPA in 2009 to force action on the issue. “But is the work done? No, of course not. It’s a floor to build on, providing a minimal level of protection.” The oil and natural gas industry has its own concerns about the new rules but has indicated it can work with them. In a press release issued the day the rules were announced, Howard Feldman, director of regulatory and scientific affairs for the American Petroleum Institute, said, “EPA has made some improvements in the rules that allow our companies to continue reducing emissions while producing the oil and natural gas our country needs.”3

Courtship Behavior in the Cuban Ameiva (Ameiva auberi ustulata, Squamata: Teiidae) from the Siboney-Juticí Ecological Reserve in Eastern Cuba


 
 
 
 The genus Ameiva Meyer 1795 comprises 23 species of which 14 are found in Central and South America and 18 occur in the West Indies. These lizards occupy diverse habitats (e.g., grasslands, tropical forests, sandy beaches) but most species appear to prefer open areas. They are ground-dwellers and active diurnal foragers. Cuba harbors only one species, Ameiva auberi. However, 40 subspecies are distributed widely across the main island, adjacent cays, and on into the Bahamas. Reproductive behavior has been documanted in some species in the family Teiidae, but not for A. auberi, about which only one published account reported the underground deposition of a single egg. Herein, we describe for the first time the reproductive behavior (except ovipositioning) of A. auberi ustulata in natural habitat in the Ecological Reserve Siboney-Jutici (eastern Cuba) on 22-25 July 2009. Between 1200 and 1600 h, we observed six mating pairs directly or while using monocular Nikon Fieldscopes. We describe three sequential stages of reproductive behaviior: (1) Pursuit, (2) prematiing and mating, and (3) excavation, with a total duration of 64.8+-17.6 min (46-92 min).
 
 
 

Radioactive series disequilibria in underground uranium deposits of the Singhbhum Shear Zone, Eastern India

Radionuclides of the 238U series (226Ra, 210Pb, 234Th and 234U), 235U series (227Ac and 231Pa) and 232Th series (228Th and 228Ra) series were measured by High Resolution Gamma Spectrometry system in twenty-five uranium ore samples from underground uranium deposits in the Singhbhum Shear Zone of Eastern India. The activity concentrations were observed to vary within a wide range in most of the deposits, as is the case in most rocks of crustal origin. The uranium ore from these deposits were not of high ore grade (U concentrations ranged from 0.015 to 0.082%). Activity ratios of key daughter–parent pairs from the decay chains, viz. 226Ra/238U, 226Ra/210Pb, 231Pa/235U, 227Ac/235U, 230Th/238U, 234U/238U, 226Ra/230Th and 228Th/228Ra indicated migration/accumulation of uranium and radium in some samples. The 226Ra/230Th ARs suggested that the deposits were not closed to groundwater movement for a maximum time period of 8ky. Thiel plot of the 234U/238U vs. 230Th/238U activity ratios indicated uranium accumulation and complex processes of uranium redistribution.

X-ray fluorescence microchemical analysis and autoradiography applied to cave deposits: speleothems, detrital rhythmites, ice and prehistoric paintings

This article presents recent research on the sedimentary endokarstic infillings in connection with the new contributions of geochemical analysis by autoradiography and X-ray fluorescence (portable analyser, core scanner, micro-XRF, microprobe) in the context of the 'Climanthrope' ANR programme. Coupled with sedimentological analysis (stratigraphy, laser grain size analysis, micromineralogy, and micromorphology), geochemical analysis and imaging refine the study of underground deposits such as carbonated sediments (speleothems), rhythmites, subterranean ice, and prehistoric cave paintings. Formed following a seasonal cycle, stalagmites and rhythmites are likely to provide important data not only on the two main parameters of regional climate, i.e. hydrology and temperature, but also on human impacts (speleothems in urban tunnels) and the rural environment. The microdebris and dusts sampled in subterranean ice record the palaeoenvironment by snow trapping. Parietal paintings can be studied directly with a portable XRF analyser without sampling. In every case, the notion of the 'site effect' is discussed for four French examples (Pyrenees, Aquitaine, Charente, Rhône) and three foreign examples (Italy, Chile, China).

Estimation of shear strength recovery and permeability of single rock fractures in shear-hold-shear type direct shear tests

The evolution of the long-term mechanical, hydraulic, and transport characteristics of rock fractures should be predicted in advance by considering the issue of the underground deposits of the energy byproducts of high-level radioactive waste. This paper presents slide-hold-slide direct shear–flow coupling experiments conducted for mortar and granite specimens with single fractures so as to investigate the effects of load holding on the mechanical properties of rock joints. From the experimental results, it is confirmed that the shear strength of the mortar replica specimens increases and the permeability decreases during 3 days of load holding. However, no significant changes are observed for the mechanical or the hydro-mechanical properties of the granite specimen even after 20 days of load holding. It is also confirmed that the shear strength of the mortar specimens increases in both short- and long-time holding cases. However, the evolution of shear strength recovery is found to be different for the two cases. This is because the dominant factor in the shear strength recovery during short-time holding may be attributed to a purely mechanical process, like creep deformation at the contacting asperities, while the shear strength recovery during long-time holding is affected by both mechanical and chemical processes. Moreover, to reproduce the shear strength recovery during short-time holding, we develop a direct shear model by employing a temporal variation in the dilation that occurs during load holding. The model predictions are in relatively good agreement with the experimental observations in the range of the short-holding period.

Carbon Capture and Storage (CCS) - técnicas aplicadas à produção de cimento

As tecnicas de captura e de armazenamento de carbono sao de extrema importância para a reducao das emissoes desse gas de efeito estufa para a atmosfera. As CCS (Carbon Capture and Storage) utilizam mecanismos fisico-quimicos para separar esse poluente e outras tecnicas de compressao para armazenar geologicamente o dioxido de carbono que e emitido por fontes fixas, como e o caso do forno de clinquer, utilizado na producao de cimento. Este trabalho foi desenvolvido para sugerir possibilidades de uso de algumas das tecnicas de CCS, direcionadas a producao de cimento. As tecnicas de pos-combustao e oxi-combustao sao propostas para a separacao do dioxido de carbono, e o transporte tubular e rodoviario sao indicados para transporta-lo. O armazenamento geologico e sugerido, na jazida Candiota (RS- Brasil), para o armazenamento definitivo do CO2 . A metodologia empregada para a realizacao do trabalho foi a pesquisa bibliografica para o levantamento das tecnologias existentes, calculos especificos para o dimensionamento de um sistema de CCS e do tempo de vida util do projeto, bem como visitas tecnicas para o levantamento das atuais condicoes do processo do forno de clinquer numa fabrica de cimento de Pinheiro Machado (RS), como temperatura, pressao e volume de saida.

Enregistrement et modélisation 3D de la fouille archéologique et paléontologique du cône d'entrée d'Orgnac (Ardèche, France)

The underground deposit of the Orgnac aven is an accumulation that could host a wildlife trapped in the Quaternary. It has a pure morphology, unconstrained by wall effects. For two years, this deposit is the subject of archaeological and paleontological excavations and is studied by lasergrammetry. This preliminary work shows the integration of spatial data for the research in the 3D model and presents some perspectives : sedimentary surface fitting, taphonomic analysis, 3D reconstruction and virtual reality.

AVA seismic reflectivity analysis in carbon dioxide accumulations: Sensitivity to CO2 phase and saturation

Abstract Seismic monitoring of sequestered carbon dioxide (CO 2 ) in underground deposits is a matter of growing importance. The subsurface monitoring of this greenhouse gas is possible due to the marked contrast between the physical properties of natural reservoir fluids and those of carbon dioxide after the injection. This technique makes necessary the investigation of appropriate seismic indicators to link seismic attributes to petrophysical properties, composition and state of the rock as well as pore-fluid type and in-situ physical conditions. With this motivation in mind, we use a Biot–Gassmann formulation to model the theoretical P-wave amplitude reflection coefficients vs. angle of incidence in the seismic range when a planar P-wave strikes the interface between a caprock and a porous sandstone which has its pore space saturated by a mixture of CO 2 with brine or oil at different states (supercritical, liquid and gas). The effects of dissolution of CO 2 in oil and the existence of a saturation threshold, above which a free CO 2 phase develops, are included in the computations. Attention is particularly focused on the sensitivity of the classic best-fit amplitude variations with angle coefficients, to different degrees of CO 2 saturation. We conclude from this analysis that the changes in seismic AVA attributes between 30 and 40 degrees can be useful to infer bounds on the CO 2 saturation degree, to detect the presence of immiscible CO 2 phase and, in some cases, to infer the physical state of the accumulations.

What determines the way of deposition of excavated soil

Subterranean rodents continuously extend their burrow systems primarily in search of food, which has an important impact on the ecosystem in which they live. Excavated soil may be pushed either into aboveground mounds or into tunnels underground. Factors affecting the amount of burrowing and the preference of aboveground or underground soil deposition are, nevertheless, little known. We investigated the influence of food supply, soil hardness, and the animal’s body mass on the mode of soil deposition in ten burrow systems of free ranging silvery mole-rats Heliophobius argenteocinereus Peters, 1846. In each burrow system, we estimated the volume of backfilled tunnels and the volume of soil deposited aboveground. The highest amount of variation in these parameters was explained by the interaction of food supply and soil hardness. The ratio of the volume of backfilled tunnels to the volume of mounds was not significantly dependent on any of the explanatory variables. The proportion of backfilled tunnels decreased with the increasing volume of the complete burrow system. We propose that both low food supply and soft soil lead to an increased amount of burrowing, which results in a larger volume of soil deposited both above ground and under ground over a given period of time.

The geochemistry of Boron-rich groundwater of the Karlovassi Basin, Samos Island, Greece

Abstract The upper Miocene of Karlovassi Basin, Samos Island, Greece, contain continental evaporites such as colemanite, ulexite, celestite, gypsum and thenardite. These evaporites are related with volcanic tuffs, diagenetically altered in a saline-alkaline lake environment. The aim of the present paper is to: a) define the impact of the already known and possible buried borates and other evaporites to the geochemistry of the hydrogeological system of Karlovassi Basin, and; b) to assess the correlation between surface and underground evaporite deposits considering the spatial changes in the concentrations of the examined physicochemical parameters. Fieldwork, laboratory measurements and literature data revealed elevated boron values (2136–33012 ⧎/L) in the central part of Karlovassi Basin. In the same area, high amounts of strontium, sodium, lithium and sulfates also occur. It is proposed that these ions originate from the leaching of evaporites and authigenic minerals such as the Sr-rich clinoptilolite and the boron-bearing potassium feldspar. Boron values are abnormally high for freshwater aquifers, and are indicative of the presence of buried evaporites in the basin with unknown significance.

Tar on Tap

This article explores diverse ways adopted by companies to find ways to make extracting oil from the sands of northern Alberta a little easier. At Petrobank’s Whitesands site, heat from in situ combustion both melts and upgrades the bitumen in the underground deposit. Horizontal production wells carry the oil to the surface. However, even with the new processes in place, copious quantities of energy and water are needed to produce oil from sands. In situ production processes exploit bitumen deposits that are inaccessible through surface mining. The facility at EnCana’s Foster Creek site processes some of the water used to extract bitumen in situ. That recycled water is then boiled and reinjected below the surface. Environmental arguments aside, many observers contend that the only argument against exploiting the Alberta oil sands that might have any success is economic—that it might cost more than alternatives. The paper concludes that barring some unforeseen calamity, oil demand is expected to outstrip the capacity of conventional petroleum production. Even if wringing oil from the Alberta sands is expensive and energy-intensive, it is probably a cost most consumers will be willing to pay for access to the next easiest oil.

Prospecting for coal in China with remote sensing

Abstract With the rapid development of China's economy, coal resources are increasingly in great demand. As a result, the remaining coal reserves diminish gradually with large-scale exploitation of coal resources. Easily-found mines which used to be identified from outcrops or were buried under shallow overburden are decreasing, especially in the prosperous eastern regions of China, which experience coal shortages. Currently the main targets of coal prospecting are concealed and unidentified underground coal bodies, making it more and more difficult for coal prospecting. It is therefore important to explore coal prospecting by taking advantage of modern remote sensing and geographic information system technologies. Given a theoretical basis for coal prospecting by remote sensing, we demonstrate the methodologies and existing problems systematically by summarizing past practices of coal prospecting with remote sensing. We propose a new theory of coal prospecting with remote sensing. In uncovered areas, coal resources can be prospected for by direct interpretation. In coal bearing strata of developed areas covered by thin Quaternary strata or vegetation, prospecting for coal can be carried out by indirect interpretation of geomorphology and vegetation. For deeply buried underground deposits, coal prospecting can rely on tectonic structures, interpretation and analysis of new tectonic clues and regularity of coal formation and preservation controlled by tectonic structures. By applying newly hyper-spectral, multi-polarization, multi-angle, multi-temporal and multi-resolution remote sensing data and carrying out integrated analysis of geographic attributes, ground attributes, geophysical exploration results, geochemical exploration results, geological drilling results and remote sensing data by GIS tools, coal geology resources and mineralogical regularities can be explored and coal resource information can be acquired with some confidence.

Halophilic archaea isolated from man-made young (200 years) salt lakes in Slănic, Prahova, Romania

Abstract We isolated a number of extremely halophilic archaea from four salt lakes (Red Bath, Green Bath, Shepherd Bath and Bride Cave) located in Slanic Prahova, Romania. The characterization of 12 representative isolates by polyphasic approach revealed that 11 strains were members of the genus Haloferax and only one was a member of the genus Haloarcula. The 11 Haloferax isolates possessed sulfated diglycosylarchaeol-1 as the major membrane glycolipid, and G+C contents of total DNA were 63.4–65.8 mol%. The predominant isolation of Haloferax species from the lakes may suggest that the underground salt deposit possesses Haloferax species as the major biota of ancient origin. To the best of the authors’ knowledge, this is the first paper on the survey of halophilic archaea of man-made young salt lakes.

Energy: towards nuclear breeder installations before the end of this century?

To play an essential role in the energy crisis, the civilian nuclear fission industry urgently requires a large and safe underground deposit for irradiated materials. Breeder reactors should be required to extract more energy, not to eventually reduce the radioactivity of dangerous materials. These two aims still require much work, from the fundamental issue of the mechanics of materials, to large industrial parks for breeder development on an international basis. To cite this article: R. Dautray, J. Friedel, C. R. Mecanique 335 (2007).

Biopedturbation by an island ecosystem engineer: Burrowing volumes and litter deposition by sooty shearwaters (Puffinus griseus)

Seabirds can influence entire island ecosystems through the effects of their burrowing and of their underground deposition of vegetation on biotic and abiotic island processes. This study quantifies the extent of these effects at three sooty shearwater breeding islands in southern New Zealand, with the aim of assessing the importance of this species as an ecosystem engineer. Mean burrow volumes ranged between 158.2 and 528.1 m3 ha–1. Between 18 and 34% of the ground surface was undermined by burrow space on the three islands. This extent of burrowing is comparable to that of fossorial mammals, widely recognised as ecosystem engineers. Mean vegetation inputs (dry weight), transported underground by birds and incorporated into nests, varied between 33 and 96 g m‐2 The implications of the biopedturbation caused by sooty shearwater burrowing to the extent measured in this study may be profound for some ecosystem processes, and certainly warrants further research.

A transaction cost model of contract choice: The case of petroleum exploration

The growing literature on transaction costs posits that the structures of contracts involving exchange under uncertainty are influenced by the costs incurred by the contracting parties prior to, as well as after, a contract is signed. This research investigates the contractual responses to the substantial uncertainty attending the exchange of rights to underground petroleum deposits. It develops a transaction cost model to explain the payment structure found in these contracts. The model identifies the major transaction costs associated with the payment types used in oil and gas exploration contracts, including ex ante measurement costs and ex post production inefficiencies, and explains their effect on contract structure. Testable implications concerning variations in the payment structure of petroleum exploration contracts are generated and tested using data from private oil and gas mineral rights leasing contracts in four western states. The study has direct public policy significance in that it delineates the implications of different payment structures of oil and gas leasing contracts. These implications can be used to evaluate proposals to reform federal oil and gas leasing policies. In addition, while there has been considerable analysis of federal offshore oil and gas leasing contracts, there has been a dearth of research on private onshore oil leasing practices. This study helps to fill this empirical void.

Taxes and Non-Renewable Resources: The Impact on Exploration and Development

Oil & gas projects consist of a series of options. The mineral owner must first decide whether to spend money on in order to learn the extent of potential reserves, the cost and timing of recovering the reserves, and the probability that the reserves are actually recoverable. The mineral owner holds an since the owner need not explore immediately but may wait until an increase in mineral makes the potential rewards from exploration more promising. After exploration of a property, the owner holds a The owner may pay to drill a test well to see if the reserves are recoverable, or the owner may put off any such test until are higher. If the test well proves there are recoverable reserves, the owner has a This option consists of the ability to complete the test well as a producer, and to drill and complete any other wells required to completely drain the recoverable reserves. The incentives for exploration, development, and production depend on the prices at which an investor will execute each option. This article examines the impact of various tax policies on exploration and development threshold prices, using a simplified production model that collapses the production option into the development option. Capitalizing rather than expensing development costs (such as intangible drilling costs) creates incentives to do projects that have a lower probability of success, that have shorter well lives, and that have lower development costs. This shift in incentives creates a nonneutrality, causing investors to develop some properties prematurely while unduly delaying the development of other projects. Capitalizing development costs also causes a slight increase in the exploration threshold price and therefore reduces exploration. Capitalizing rather than expensing exploration costs (such as the costs of seismic analysis to detect potential underground deposits) results in a more complicated pattern of effects. This policy causes a large increase in the exploration threshold price, thereby reducing exploration. Since the taxpayer will not recover capitalized exploration costs until development, this policy also reduces the cost of development and lowers development threshold prices. As a consequence, capitalizing exploration costs results in more intensive development and production of known reserves as well as reduced exploration. This pattern is undesirable if the goal is to enhance national security by encouraging the creation of a pool of reserves that are available for immediate exploitation in case foreign supplies become unavailable. It also is possible that taxpayers may be able to circumvent most of the impact of rules requiring capitalization of exploration costs by strategically realizing losses. This possibility may blunt the undesirable national security impact of such rules, but the costs of the associated trading are social costs that would not arise under expensing.