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Auswahl der wissenschaftlichen Literatur zum Thema „CORE DRILLING THEORY“
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Zeitschriftenartikel zum Thema "CORE DRILLING THEORY"
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Schwander, J., S. Marending, T. F. Stocker und H. Fischer. „RADIX: a minimal-resources rapid-access drilling system“. Annals of Glaciology 55, Nr. 68 (2014): 34–38. http://dx.doi.org/10.3189/2014aog68a015.
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AbstractDetermining the expected age at a potential ice-core drilling site on a polar ice sheet generally depends on a combination of information from remote-sensing methods, estimates of current accumulation and modelling. This poses irreducible uncertainties in retrieving an undisturbed ice core of the desired age. Although recently perfected radar techniques will improve the picture of the ice sheet below future drilling sites, rapid prospective drillings could further increase the success of deep drilling projects. Here we design and explore a drilling system for a minimum-size rapid-access hole. The advantages of a small hole are the low demand for drilling fluid, low overall weight of the equipment, fast installing and de-installing and low costs. We show that, in theory, drilling of a 20 mm hole to a depth of 3000 m is possible in ∼4 days. First concepts have been realized and verified in the field. Both the drill cuttings and the hole itself can be used to characterize the properties of the ice sheet and its potential to provide a trustworthy palaeo-record. A candidate drilling site could be explored in ∼2 weeks, which would enable the characterization of several sites in one summer season.
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Li, Zhan Tao, Yong Zheng Ma und Ken-ichi Itakura. „Development of a Rotary Drilling Mechanism for Impregnated Diamond Bits“. Advanced Materials Research 989-994 (Juli 2014): 3136–39. http://dx.doi.org/10.4028/www.scientific.net/amr.989-994.3136.
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Impregnated diamond core bits are often used in core drilling for geological surveys. A tri-state theory is proposed to describe the three states in drilling processes for a diamond particle or a bit. These states are contacting state, cutting state, and ploughing state. Furthermore, the relations among thrust and other mechanical parameters are also summarized. The optimal value of the specific energy is in the cutting state. Several experiment results verified the proposed model. This mechanism is useful for selecting operation parameters in core drilling using impregnated diamond core bits.
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Talalay, P. G. „Perspectives for development of ice-core drilling technology: a discussion“. Annals of Glaciology 55, Nr. 68 (2014): 339–50. http://dx.doi.org/10.3189/2014aog68a007.
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AbstractMore than 170 years ago, Louis Agassiz, one of the creators of glacial theory, made his first attempt to drill into the bed of Unteraargletscher, Swiss Alps. Since that time, various systems for thermal and mechanical drilling have been designed especially for boring into ice, and some conventional drill rigs been adopted for ice coring. Although contemporary ice-drilling knowledge and techniques are now familiar, there remain many problems to be solved by advanced modern technology. Specific challenges related to improving old drilling methods and developing new emerging technologies include: (1) identification of depth limitation of ‘dry’ drilling; (2) improvement of casing; (3) searching for the new environmentally friendly low-temperature drilling fluids; (4) reliable elimination of sticking drills; (5) improvement of core quality in the brittle zone; (6) additional core sampling from borehole walls after the core has been drilled; (7) obtaining oriented core; (8) designing automation drilling systems; (9) developing rapid-access drills. Possible ways of solving these problems are presented below.
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Zhu, Lun. „Experimental Study by Using Drilling Core Materials Inversion Formation Rock Fracture Toughness Test Research“. Applied Mechanics and Materials 538 (April 2014): 315–18. http://dx.doi.org/10.4028/www.scientific.net/amm.538.315.
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On the basis of Cliftons, hydraulic fracturing is established under the condition of cylindrical specimen fracture toughness expression. Using a self-built laboratory equipment, drilling core specimen for the fracture toughness test and obtain the relevant data. Based on the rock parameters inversion theory to construct the formation rock fracture toughness inversion objective function and optimization function. according to the drilling core material fracture toughness test data and the application of Matlab programming presented the formation rock fracture toughness.
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Kurgansky, V. „"GEOPHYSICAL RESEARCHES OF MINING HOLES" – 50 YEARS AT TARAS SHEVCHENKO NATIONAL UNIVERSITY OF KYIV“. Visnyk of Taras Shevchenko National University of Kyiv. Geology, Nr. 1 (84) (2019): 89–94. http://dx.doi.org/10.17721/1728-2713.84.13.
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Development of carotage (retrospective years 1969-2019) at Taras Shevchenko National University of Kyiv is described. Basic achievements are shown in educational and scientific directions. Carbonate rocks methodology study problems, petrophysical models which allowed building physically well-founded dependences of "core-core", "core-geophysics", "geophysics- geophysics" type are described. Petrophysical simulation, theory of probability and mathematical statistics methods allowed the author to work out a complex system of data processing and interpretation in welllogging. Current status and tendency in dataware drilling process of the deep oil and gas wells are examined. Absolutely new ideology of operative getting of the reliable directional survey data without special logging services (telesystem in the process of drilling, autonomous inclinometer and other) is proposed.
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Wei, Na, YingFeng Meng, Gao Li, LiPing Wan, ZhaoYang Xu, XiaoFeng Xu und YuRui Zhang. „Cuttings Transport Models and Experimental Visualization of Underbalanced Horizontal Drilling“. Mathematical Problems in Engineering 2013 (2013): 1–6. http://dx.doi.org/10.1155/2013/764782.
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Aerated underbalanced horizontal drilling technology has become the focus of the drilling industry at home and abroad, and one of the engineering core issues is the horizontal borehole cleaning. Therefore, calculating the minimum injection volume of gas and liquid accurately is essential for the construction in aerated underbalanced horizontal drilling. This paper establishes a physical model of carrying cuttings and borehole cleaning in wellbore of horizontal well and a critical transport mathematical model according to gas-liquid-solid flow mechanism and large plane dunes particle transport theory.
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Azuma, Nobuhiko, Ikuo Tanabe und Hideaki Motoyama. „Heat generated by cutting ice in deep ice-core drilling“. Annals of Glaciology 47 (2007): 61–67. http://dx.doi.org/10.3189/172756407786857848.
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AbstractIn order to understand and solve the ‘warm-ice problem’ in deep ice-core drilling, we applied the metal-cutting theory to ice and estimated the heat generated during ice coring taking into account the mechanical and thermal properties of the ice and cutters. We found that (1) most of the heat in cutting is generated by shear deformation at the shear plane of ice, and the heat could increase the chip temperature by several degrees; (2) the rake angle of the cutter has more influence on the temperature increase in chips than the barrel rotation speed and penetration pitch; (3) if the cutter is made of a material with larger thermal conductivity, the temperature increase in the chips can be reduced; and (4) if the density of the liquid is less than the density of ice, the cutting chips sink to the bottom and the friction heat generated by the drill head and slush can raise the ambient temperature of the drill head by several degrees.
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Sedaghatzadeh, Mostafa, Khalil Shahbazi, Mohammad Hossein Ghazanfari und Ghasem Zargar. „The Impact of Nanoparticles Geometry and Particle Size on Formation Damage Induced by Drilling Nano-Fluid during Dynamic Filtration“. Journal of Nano Research 43 (September 2016): 81–97. http://dx.doi.org/10.4028/www.scientific.net/jnanor.43.81.
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In this paper, the impact of three parameters including nanoparticles geometry, particles aggregation and borehole inclination on induced formation damage from water based drilling fluids were investigated by means of experimental studies. Accordingly, we designed a dynamic filtration setup capable to rotate and change well inclination. nanobased drilling fluids consisting of spherical, cubical and tubular shapes nanoparticles as fluid loss additives were used. Mud cake quality, core permeability impairment and degree of formation damage at various well inclinations were examined. The cluster structure of aggregated particles were determined using fractal theory and applying dynamic light scattering technique. For this purpose, drilling fluids were circulated at different well inclinations and at a constant differential pressure against a synthetic core. Field emission scanning electronic microscopy images taken from mud cakes confirmed the proposed cluster structures of nanoparticles. The experimental results show that the mud cake quality and degree of damage are functions of produced structure of aggregated particles. Moreover, by increasing the well inclination, the skin factor increases. However, this trend is intensively depended on particle geometry. Real time analysis of pore throat size to particle size ratio during mud circulation shows the tendency of particles to create external/internal filter cake is mainly related to well inclination and particle shape. The results can be used to optimize the size and shape of selected macro/nanoparticles as additives in drilling fluids to reduce formation damage in directional and horizontal wells during drilling operation.
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Jiang, An Nan, und Zheng Wen Zeng. „Three Dimensional Numerical Simulation of Rock Core Discing Based on Strain Soft Model“. Advanced Materials Research 187 (Februar 2011): 565–69. http://dx.doi.org/10.4028/www.scientific.net/amr.187.565.
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Aiming at the complexity of rock discing mechanics, and the theory being not mature, the paper carried out three-dimensional numerical simulation for rock core discing based on strain soft model. The strain soft theory is introduced firstly, then numerically simulated how the depth of lug boss and original stress affect the rock core destroy pattern(discing if occurs, the thickness of disk), obtained the characters of rock core discing. Along with the drilling depth increases, the stress concentration scope below lug boss also increases, as well as the pressure stress concentration degree of side corner below of lug boss. Rock core discing can be induced respectively by shear action and tension action, sometimes it is combined by both of them. The destroy pattern of them especially destroy sequence are different. The strain soft numerical simulation could be used in original stress feedback analysis, has significant meaning.
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Cao, Pinlu, Miaomiao Liu, Zhuo Chen, Baoyi Chen und Qi Zhao. „Theory calculation and testing of air injection parameters in ice core drilling with air reverse circulation“. Polar Science 17 (September 2018): 23–32. http://dx.doi.org/10.1016/j.polar.2018.06.005.
Der volle Inhalt der QuelleDissertationen zum Thema "CORE DRILLING THEORY"
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Maštera, Lukáš. „Koncepce vysokorychlostní vrtné hlavy pro odběr vzorků hornin“. Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2021. http://www.nusl.cz/ntk/nusl-443237.
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THE THESIS FOCUSES ON A CONSTRUCTION DESIGN OF A NEW DRILLING HEAD DESIGNED TO REPLACE THE ORIGINAL ONE IN A MULTIDRILL HYNDAGA DRILLING RING. THE SUBSTITUTION IS SUPPOSED TO PROVIDE A SOLUTION TO THE SHORTCOMINGS OF THE CURRENTLY USED DRILLING HEAD. THE THESIS ANALYSES PARAMETERS OBTAINED FROM THE MANUFACTURER, NEW PRODUCTION REQUIREMENTS AND PROPOSES TWO TYPES OF MOTORS INNOVATIVE METHODS HAD BEEN IMPLEMENTED IN CALCULATIONS OF CONCEPTUAL PARAMETERS OF THE NECESSARY COMPONENTS. THE OUTCOME IS A NEW F-TYPE DRILLING HEAD.
Bücher zum Thema "CORE DRILLING THEORY"
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Livermore, Roy. Probably the Best Theory on Earth. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780198717867.003.0002.
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The magnetic bar-code on the ocean floor provides convincing evidence of moving continents, yet, as with the discovery of the structure of DNA, few are convinced—at first. Drilling in the deep oceans and geochemical work at mid-ocean ridges provides further evidence in support of the Vine–Matthews Hypothesis. Application of the hypothesis to data collected in the Pacific and Atlantic Oceans establishes sea-floor spreading as the process that creates new oceans and, in conjunction with reversals of the geomagnetic field, stamps the bar-code into the rocks beneath the sea bed.
Buchteile zum Thema "CORE DRILLING THEORY"
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Molnar, Peter. „2. Seafloor spreading and magnetic anomalies“. In Plate Tectonics: A Very Short Introduction, 17–35. Oxford University Press, 2015. http://dx.doi.org/10.1093/actrade/9780198728269.003.0002.
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‘Seafloor spreading and magnetic anomalies’ begins with the Vine–Matthews Hypothesis, which proposed that strips of seafloor parallel to the mid-ocean ridges, where two plates diverge from one another, were magnetized in opposite directions because the Earth’s field had reversed itself many times. A test of the Vine–Matthews Hypothesis, which required determining the age of the seafloor, became a test of seafloor spreading. Dating the ocean floor using magnetic anomalies detected by magnetometers towed behind ships and core samples extracted during the Deep-Sea Drilling Project confirmed the hypothesis. With magnetic anomalies to date the seafloor and a curve relating seafloor depth and age, the difference between the Atlantic, with its ‘ridge’, and the Pacific and its ‘rise’ became comprehensible. With a theory for predicting the depths of oceans, it was also possible to understand the history of sea-level changes.
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Matanovic, Davorin. „The Macondo 252 Disaster“. In Risk Analysis for Prevention of Hazardous Situations in Petroleum and Natural Gas Engineering, 115–31. IGI Global, 2014. http://dx.doi.org/10.4018/978-1-4666-4777-0.ch006.
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The disaster of the Deepwater Horizon platform, while drilling the Macondo 252 well in the Gulf of Mexico in 2010 is for now the last of numerous tragedies, blowouts, and oil spills resulting from petroleum engineering activities. After the accident, several commissions, investigation groups, advisory committees, and company reports were prepared. They investigate causes and consequences of the disaster from different standpoints, but mainly come to the same conclusions. The “nth” approach is presented in this chapter.
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Gaines, Susan M., Geoffrey Eglinton und Jürgen Rullkötter. „Deep Sea Mud: Biomarker Clues to Ancient Climates“. In Echoes of Life. Oxford University Press, 2008. http://dx.doi.org/10.1093/oso/9780195176193.003.0011.
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Though the concept of the biomarker emerged from attempts to infer the provenance of petroleum and the incidence of life on the young earth—for all the successes and disappointments of the early studies on Precambrian rocks, lunar dust, and oil shales—it was in the sediments of the deep sea that biomarkers really came into their own. The Deep Sea Drilling Project (DSDP) was initiated in the 1960s by a consortium of American oceanographic research institutions, but institutions in Russia, the United Kingdom, France, and Germany were quick to sign on. In what began as an effort to understand the makeup and dynamics of the earth’s crust and mantle, the DSDP’s special research ship traveled the world’s oceans, drilling thousands of meters into the seafloor to retrieve sediment cores that soon became coveted objects of study for geologists, oceanographers, biologists, paleontologists, and geochemists around the world. When Geoff’s group started analyzing the DSDP sediments in the early 1970s, most of the organic chemists involved with the program were from the oil industry and formed part of the drill ship’s safety program, monitoring the cores as they were brought on deck to ensure that dangerous accumulations of gas or liquid hydrocarbons weren’t being penetrated. But Geoff saw the DSDP as the perfect opportunity to wean his Bristol lab of its dependence on NASA’s Apollo program—a chance to bring his full attention back to Earth and its still largely unexplored realm of fossil molecules. The British Natural Environment Research Council had earmarked a large pot of funding for work on the cores, which would be unencumbered by the narrow commercial goals and secrecy that surrounded the limited offerings from oil-company bore holes. Geoff’s budding Organic Geochemistry Unit would be aligned with a multidisciplinary community of scientists who were all studying the same cores, working cooperatively, and publishing freely. And, unlike the lunar samples, ocean sediments were rife with interesting organic compounds, including many entirely unforeseen structures. Most of the cores consisted of sediments that had been laid down and buried sequentially without ever being subjected to the tectonic turmoil of stretching and subsidence, and the overlying kilometers of cold water had kept their temperatures relatively low.
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Oliveira, Grace Juliana Gonçalves de, Wolf Uwe Reimold, Álvaro Penteado Crósta, Natalia Hauser, Christian Koeberl, Dieter Mader, Ralf-Thomas Schmitt und Tanja Mohr-Westheide. „Terrestrial and extraterrestrial chemical components of early Archean impact spherule layers from Fairview Gold Mine, northern Barberton greenstone belt, South Africa“. In Large Meteorite Impacts and Planetary Evolution VI. Geological Society of America, 2021. http://dx.doi.org/10.1130/2021.2550(12).
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ABSTRACT Early Archean spherule layers, widely accepted to represent distal ejecta deposits from large-scale impact events onto the early Earth, have been described from several stratigraphic levels of the Barberton greenstone belt in South Africa. Recently, exploration drilling at the Fairview Gold Mine (25°43′53″S, 31°5′59″E) in the northern domain of the belt resulted in the discovery of a new set of spherule layer intersections. The Fairview spherule layers in drill cores BH5901, BH5907, BH5911, and BH5949 were intersected just a few meters apart, at about the same stratigraphic position within the transition from the Onverwacht Group to the Fig Tree Group. The Fairview spherule layers have petrographic and chemical similarities to at least three other well-known Barberton spherule layers (S2–S4), and multiple spherule layer bed intersections in drill cores BARB5 and CT3, all from about the same stratigraphic position. They are not uniform in composition, in particular with respect to abundances of highly siderophile elements. The highest concentrations of moderately (Cr, Co, Ni) and highly siderophile (Ir) elements are within the range of concentrations for chondrites and, thus, reinforce the impact hypothesis for the generation of the Fairview spherule layers. Iridium peak concentrations and Cr/Ir interelement ratios for spherule layer samples from drill cores BH5907, BH5911, and BH5949 suggest admixtures of 50%–60% chondritic material, whereas for the BH5901 spherule layer, only an admixture of 1% chondritic material is indicated. We discuss whether these four Fairview spherule layers represent the same impact event, and whether they can be correlated to any of the S2–S4, CT3, and BARB5 intersections.
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Zhang, Jie, Xu-Yang Yao, Bao-Jun Bai und Wang Ren. „Performance Evaluation and Mechanism Study of a Silicone Hydrophobic Polymer for Improving Gas Reservoir Permeability“. In 21st Century Surface Science - a Handbook. IntechOpen, 2020. http://dx.doi.org/10.5772/intechopen.90811.
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The permeability of tight gas reservoirs is usually lower than 1 md. When the external fluids from drilling and completion processes invade such reservoirs, formation damage occurs and causes serious damage to oil and gas production. Fluorocarbon surfactants are most often recommended for removing such damage because they have extremely low surface tension, which means that they can change the reservoir wettability from water wet to gas or oil wet. However, they are not normally applied in the field because they are not cost-effective. Besides, some environmental concerns also restrict their application. In this work, we studied the effects of an oligomeric organosilicon surfactant (OSSF) on wettability modification, surface tension reduction, invasion of different fluids, and fluid flow back. It was found that the amount of spontaneous imbibition and remaining water could be reduced by the surfactant as a result of surface tension reduction and wettability alteration. Compared to the distilled water, the concentration of 0.20 wt% OSSF could decrease water saturation of cores by about 4%. At a flow-back pressure of 0.06 and 0.03 MPa after 20 PV displacement, permeability recovery could increase from 8 to 7–93% and 86%, respectively. We also found that the mechanism of OSSF includes the physical obstruction effect, surface tension reduction of external fluids, and wettability alteration of the reservoir generated. Meanwhile, quantum chemical calculations indicated that adsorbent layer of polydimethylsiloxane could decrease the affinity and adhesion of CH4 and H2O on the pore surface.
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Taft, George, und Bilal Haq. „Deep Sea Fan Issues“. In Continental Shelf Limits. Oxford University Press, 2000. http://dx.doi.org/10.1093/oso/9780195117820.003.0026.
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Deep sea fans occur along many continental margins. The Bengal Fan is the world's largest elongated submarine fan area, occupying over 3 x 106 km2 of seafloor in the Bay of Bengal. The Bay of Bengal is bordered by Sri Lanka, India, Bangladesh, Myanamar, the Andaman and Nicobar Islands, and Sumatra. The fan spans an area that is 2800-3000km in length and 830-1430 km in width. At the northern end of the Bay, the sediment cover is estimated to be more than 16 km in thickness (Curray and Moore, 1971, 1974, Moore et al., 1974). Recent drilling on the distal part of the fan just south of the equator during Ocean Drilling Program Leg 116 cored nearly 1 km of sediment without reaching hardrock basement (Cochran et al., 1990). The submarine feature of the Ninetyeast Ridge divides the fan into two major lobes, the main Bengal Fan and the eastern lobe, also known as the Nicobar Fan (Curray and Moore, 1974) (figure 19.1). The fan extends from 20°N latitude and, based on recent sedimentological and channel-system studies, to beyond 9°S latitude (Stow et al., 1990; Hübscher et al., 1997). The great size of the Bengal Fan is related to the history of the collision of the Indian tectonic plate with Eurasia and the subsequent uplift of the Himalayas. The first encounter of the northward-moving Indian Plate with the Asian mainland occurred around 50 million years (my) ago in the early Eocene Epoch (Haq, 1985). The first collision caused the initial uplift in the Himalayan region. Sedimentation in the bay is inferred to have started after this first collision, but extensive sedimentation probably did not begin until the early Miocene (ca. 17 my ago) after a major uplift in the Himalayas (Haq, 1985). Weathering and denudation of the Himalayas has furnished huge volumes of sediments that have built the Bengal Fan, supplied through the Ganges and Brahmaputra Rivers and their delta (figure 19.2). Sediments are transported largely by turbidity currents across the submerged continental terrace in the proximal part of the fan through a major delta-front canyon, also known as the Swatch-of-No-Ground. Currently, this canyon discharges its load into a single active channel that supplies sediment to the entire length of the fan.
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Newman, Richard S. „Widening the Circle of Influence“. In Love Canal. Oxford University Press, 2016. http://dx.doi.org/10.1093/oso/9780195374834.003.0015.
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Although known as “Mr. Clean” for his longtime environmental advocacy, Edmund Muskie had little knowledge of the American hazardous waste grid until 1978. A congressional sponsor of the landmark Clean Air and Clean Water Acts, the senator from Maine epitomized environmental politics. In fact, a few months before the Love Canal crisis unfolded, Muskie proposed yet another federal environmental law: a “comprehensive scheme to assure full protection of our national resources” in the wake of oil drilling disasters, tanker spills and toxic train derailments. Yet Muskie soon realized that his plan omitted something important: hazardous waste dumps. Love Canal had illuminated the toxic perils many Americans faced in their own neighborhoods. With an EPA study showing that tens of thousands of old toxic sites had yet to be contained, it was clear that the everyday landscape of homes, playgrounds, and schools needed environmental protection too. “In our society,” Muskie told an interviewer in the late 1970s, ...we are discovering almost every day, in almost every day’s newspaper, new hazards that have been released into the atmosphere over the period of our industrial revolution. [They] suddenly crop up in Love Canal, up in New York State … to create enormous hazards to public health, property values, to people. So we are constantly dealing with problems that [we] were not anticipating, which suddenly create almost insoluble problems for people and communities … [A]ll of these poisons and toxic materials were buried in landfill sites here, there, and elsewhere and sadly begin leaking in underground water, or into lakes and rivers, streams[,] only to rise up to hit people in the face with disease, with cancer, declining property values so on.... For Muskie, Love Canal was revelatory. It showed that federal law lagged behind the mounting problem of hazardous waste. After hearing Love Canal residents’ testimony, he believed that the time had come for a national statute governing toxic waste remediation—what he would refer to as a “clean land” law.
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Emery, K. O., und David Neev. „Introduction“. In The Destruction of Sodom, Gomorrah, and Jericho. Oxford University Press, 1995. http://dx.doi.org/10.1093/oso/9780195090949.003.0004.
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The thrilling biblical saga of Sodom and Gomorrah leaves a deep impression on the spirit of its readers, especially the young. Basic ethical concepts such as right and wrong were dramatically portrayed by that simple and cruel, yet humane, story. Memories of even more ancient disastrous geological events apparently were interwoven into the saga. A geologist cannot remain indifferent when investigating the Dead Sea region and observing stratigraphical and structural evidence of past and continuing similar events. Forceful dynamics indicated by vertically tilted beds of rocksalt layers that have penetrated upward through the ground and by later processes that have shaped some beds into pillars trigger association with the ancient story. Such features are abundant and clearly recognizable along the foot of the diapiric structure of Mount Sedom (Arabic Jebel Usdum). A gas blowout during the drilling of a water well near the Amazyahu fault in 1957 only by good luck failed to produce a gush of fire and smoke. Such an event could have happened in ancient times as a natural result of faulting. Knowledge of the regional geological background permits translation of the biblical descriptions into scientific terms, which suggests that the sagas of Sodom, Gomorrah, and Jericho described real events that occurred during ancient times before much was known about geology. Thirty-five years of the authors' professional experience in the Dead Sea region encompasses many geological aspects of the basin: deep and shallow stratigraphy, structural history, seismology, sedimentological processes, and the physical and chemical properties of the water. Archaeological studies in the region are reviewed. Although most of these studies are applicable to exploration for oil and gas or extraction of salts from brines, their results illuminate the role of changing paleogeography and paleolimnology on human environments. Climate changes and lake-level fluctuations have occurred since Mid-Pleistocene, especially during the past 50,000 years. Studies of sediments from shallow core holes delimit coastal areas that when exposed by drops in the level of the Dead Sea, quickly developed soils that could be used for agriculture.
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Pawlowsky-Glahn, Vera, und Richardo A. Olea. „Application to real data“. In Geostatistical Analysis of Compositional Data. Oxford University Press, 2004. http://dx.doi.org/10.1093/oso/9780195171662.003.0013.
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Methods for spatial correlation analysis and estimation of r-compositions introduced in the foregoing chapters are illustrated here by an example that draws upon real data taken from the Lyons West oil field located in west-central Kansas, USA. Data consist of core analyses of water saturation, saturated thickness and average reservoir porosity over the connate saturated interval at different locations in the Lyons West field. These data are used to compare different possible methods for predicting regionalized compositions. The methods we consider are: 1. a direct approach for estimating compositional variables derived from the original measurements; 2. the basis method, applicable only when there is a random function that can be regarded as the size or accumulation of the regionalized variable under study; 3. the logratio approach, using the additive logratio (air) transformation. Kriging and cokriging estimation methods will be considered for original compositions and for transformed data. Software used for statistical analyses include GSLIB, programs written by Ma and Yao (2001) and ad hoc programs written by the authors. GSLIB is a public-domain library of geostatistical programs written in Fortran (Deutsch and Journel 1998); the other programs are available from their authors. The Lyons West oil field is located at 98° 15' west longitude and 38° 20' north latitude in west-central Kansas, near the center of the United States. The reservoir occurs in Mississippian (Lower Carboniferous) rocks that originated as sediments deposited in the shallow interior sea that covered much of North America in the late Paleozoic. The field was discovered somewhat accidentally in 1963, during the drilling of a deeper Ordovician prospect. Initial oil in place was estimated at 22 million stock-tank barrels of oil. The genesis of the reservoir, composed of carbonate-cemented sands, is interpreted as an offshore bar enclosed in marine shales. Regional uplift tilted the sand body, which was truncated along the western margins by the unconformity marking the base of the Pennsylvanian (Upper Carboniferous). The sandstones interfinger with marine shales to the east, but the eastern margin of the reservoir is defined by the intersection of the oil-water contact with the shale seal at the top of the reservoir interval (Ehm 1965).
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De Blij, Harm. „Lowering the Barriers“. In The Power of Place. Oxford University Press, 2008. http://dx.doi.org/10.1093/oso/9780195367706.003.0014.
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Becoming conscious of one’s cultural and physical environments early in life involves fast-developing recognition of circumstances malleable and immutable. By the time we are about six years old, our brain is about as big as it will be for the duration, but its maturation goes on for many years more. The language-learning ability of young children, the subject of numerous studies and much speculation, undoubtedly connects this process; youngsters are able to recollect facts and vocabularies but cannot match adults or even adolescents in conceptualizing context or relationships. While we quickly learn to use words to gain immediate objectives such as nourishment or affection, it takes much longer to begin forming an understanding of our place and its (apparently) fixed attributes. Thus our perception of place changes over time, as do the opportunities to counter its formative impress. Bilingualism and multilingualism already are a key to upward mobility and will be more so in the future; exposing children in their earliest years of learning to a language other than the mother tongue will endow them with potentially immense advantages. Religious fanaticism is intensifying in many parts of the world; protecting children against it in their early years gives them the chance to develop their contextual abilities before being exposed to it. Religious leaders of all faiths would do well to consider the divine potential of pronouncements that assert the superiority of their particular beliefs and rituals over others. Pope Benedict in the spring of 2007 declared that Roman Catholicism afforded the only true route to salvation and that all other (Christian) approaches are “defective,” a proclamation Christianity and the world could have done without. Drilling into children that “there is no god but Allah” closes young minds to the religious convergence that should be the hope of all believers. It may not be absolutely true that “religion poisons everything,” the subtitle of an angry book on the topic, but religious males in medieval outfits do misuse their powers to erect barriers that last lifetimes. The power of place defines an aggregate of circumstances and conditions ranging from cultural traditions to natural phenomena, into which we are born, with which we cope, and from which we derive our own multiple identities.
Konferenzberichte zum Thema "CORE DRILLING THEORY"
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Kunakasov, Arthur Ahatovich, Evgeniy Viktorovich Kharkov und Robert Aleksandrovich Chigirev. „Mohr-Coulomb Envelope Based on Geomechanical Studies: West Siberian Fields Case Studies. Applied Methods“. In SPE Symposium: Petrophysics XXI. Core, Well Logging, and Well Testing. SPE, 2021. http://dx.doi.org/10.2118/208427-ms.
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Abstract The strength properties of the rock determine many physical processes occurring in the formation and at the bottom of the well. Deformation and destruction of rocks under the influence of external forces can be both a positive and a negative factor for working with formations at all stages of development. To create the optimal design of the well drilling trajectory, select the optimal development project, the fluids extraction rate from the formations, efficient planning and implementation of hydraulic fracturing procedures, prevention of emergencies during drilling and operation and reduction of oil recovery due to irreversible loss of reservoir properties and solving many other problems, it is necessary to consider possible destruction of the rock. The Mohr-Coulomb envelope (rock strength passport) can be used as a strength criterion for such tasks, it characterizes the boundary values of stresses in the rock, at which its destruction occurs according to the Mohr-Coulomb theory. At article discusses three methods for determinate strength passports based on the results of laboratory studies of rock samples: multistage loading of the sample, assessment of the sample fracture after triaxial compression strength test, the use of "twin" samples for testing. The features of each method, its advantages and limitations are disclosed, examples of construction of strength passports for rocks from fields in Western Siberia are shown. According to the research results, the most preferable is the use of "twin" samples. However, this method is associated with technical difficulties.
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Karimi Rad, Mohammad Saeed, Mojtaba Kalhor Mohammadi und Kourosh Tahmasbi Nowtarki. „Bridging Agents Optimization Based on Predicting Induced Fracture Model for Deviated Wells – A Case Study“. In IADC/SPE Asia Pacific Drilling Technology Conference. SPE, 2021. http://dx.doi.org/10.2118/201070-ms.
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Abstract Applying bridging agents to prevent seepage losses is a common practice during drilling reservoir sections which limits the invaded zone and reduces stuck pipe possibility. Unfortunately, the initial particle size distribution (PSD) design of bridging agents based on static models does not prevent actual seepage losses due to the induced fractures which have different sizes comparing to the initial reservoir pore sizes. This paper reviews an actual case study with provided solutions in an offshore field located in the Middle East which had a seepage loss circulation problem through induced fractures. It also presents analyzing natural and induced fractures size of the reservoir layer to choose optimized possible bridging agents’ PSD to cure/prevent loss circulation problems. The maximum/average pore size of formation can be measured from routine core analyses. A geological method to estimate the induced fracture widths with geo-mechanical data were used. Finally, optimum blends of bridging agents for loss circulation pills or background treatment to prevent mentioned problems were designed. Based on the laboratory testing on cores taken from previously-drilled wells in the mentioned field, the maximum size of pore throats was measured as 20 microns. Therefore, using the Ideal Packing Theory (IPT) method, the result for selecting bridging agents through pore throats (for seepage loss) indicates that optimum treatment is using of bridging agents with D50 and D90 6.5 and 16 microns, respectively. Also, for improving the treatment selection through parameters such as PSD of bridging agents, investigation on behavior of fracture growth were done. As a result, induced fracture width in studied well, with provided geo-mechanical (such as Poisson's Ratio & Young Modulus) and drilling fluid data was calculated approximately to be 230 microns through the porous medium in the near-wellbore region. Therefore, optimization for bridging these new fractures while drilling was performed again and it was concluded that optimum bridging agent size distribution at the tip of these newly-created induced fractures is applying bridging agents with D50 and D90 of 64 and 170 microns respectively, which are approximately 10 times higher than normal treatment in size. This paper describes the historical seepage circulation and related problems in the mentioned field and presents a methodology to prevent these issues by predicting induced fractures and optimizing bridging agent PSD to block them. Considering this methodology, the gap between the design and actual drilling is reduced and both rig downtime and related drilling and drilling fluids costs can be saved.
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Inoue, Tomoya, Junya Ishiwata, Ryota Wada und Junichiro Tahara. „Attempt of a Real-Time Drilling State Identification With Machine Learning“. In ASME 2020 39th International Conference on Ocean, Offshore and Arctic Engineering. American Society of Mechanical Engineers, 2020. http://dx.doi.org/10.1115/omae2020-19169.
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Abstract Japan Agency for Marine-Earth Science and Technology (JAMSTEC) operates the scientific drillship Chikyu for scientific research. However, Chikyu has experienced problems with respect to drill pipe failure. This may be due to the limitation of indication of anomalies such as drill pipe failure in conventional drilling data monitoring. As one of primary aims of scientific drilling is to recover core samples from sediment layers under the seabed, improving core recovery rate is very important because it can enhance the operation efficiency. Obtaining the information of lithology of drilling layer is also helpful for both scientific and operational aspects. However, there is no direct information regarding the core recovery rate and lithology. The recovery rate and lithology can be determined after retrieving a coring tool. Therefore, this study applies a machine learning technique to identify the drilling states, which includes anomaly detection of the drilling torque assuming the drill pipe failure, the prediction of core recovery rate as well as lithology. This study aims to achieve real-time drilling state identification. Accordingly, a drilling data acquisition and distribution system was developed. The drilling data distributed from the system is read by data analysis systems in several languages for real-time analysis. The drilling state identification models created in Python include the anomaly detection model and the prediction models of the core recovery and lithology. The models were installed in the real-time drilling data analyzing system, and real-time drilling state identification was attempted during the operation to confirm the health of the real-time drilling data analyzing system and to demonstrate identification with machine learning.
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Ali, Liaqat, Shan Jin und Yong Bai. „Systematic Measures to Cope With Offshore Drilling Hazards: An Interpretive Structural Modeling Approach“. In ASME 2020 39th International Conference on Ocean, Offshore and Arctic Engineering. American Society of Mechanical Engineers, 2020. http://dx.doi.org/10.1115/omae2020-19165.
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Abstract The process of offshore drilling faces several challenges. The process of mixing of water and oil results in issues that lead to the contamination of ocean water. Therefore, this study focuses on the hazards and the measures taken to cover up those hazards of offshore drilling. There are types of offshore drilling hazards such as health hazards and safety hazards. In connection to identify the hazards facing in offshore drilling and taking measures to prevent these hazards, ISM (interpretive structural modeling) technique is used. Data is collected through extensive literature review and by conducting interviews from Japan and China. Experts from academia and industry specialists are approached for interview. Eight important Measures to prevent the hazards due to offshore drilling have been identified. And the relationship among these measures are depicted by constructing SSIM (structural self-interaction matrix). The next step of ISM technique which is reachability matrix, developed which also establish the driving and dependence power of each variable. After reachability matrix a diagram is discussed where the measures are depicted in relation to their dependency, drive and independency levels, which show the influence of each measure with other. This study is valuable in the field of offshore drilling for top managers in decision making and for literature review study. Further, this study has some limitation, if the contributions of experts from other countries would have been exerted in our research that may came up with more measures for the prevention of hazards encounter in Offshore oil drilling. Further, quantitative analysis should be considered to find the absolute values to evaluate the measure.
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Spirina, Anastasiia, und Evgeniy Cherepanov. „Petroelastic Modeling of Complex Lithology Fields: Case Study“. In SPE Symposium: Petrophysics XXI. Core, Well Logging, and Well Testing. SPE, 2021. http://dx.doi.org/10.2118/208423-ms.
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Abstract The present-day growth of petroleum reserves, maintaining and enhancing of oil production is associated with involving of complex fields into production (Uspenskaya, 2014). The complex structure of the study areas of the Urai Region (facies variability, formation replacement, fracturing, crushing and cleavage zones, complicated structure of the pore space) makes conventional forecast of reservoir properties ineffective. Moreover, the pay formations are highly exhausted with high production water cut. Therefore, the search of prospective targets is relevant in the Urai Region. The article shows generalized results of petroelastic modeling of several fields of the Urai Region for solving the following tasks: ○ Lithology, saturation and poroperm properties forecast of reservoir rocks from log and seismic data; ○ Development of 1D mechanical earth models (MEM) of horizontal well sections and their maintenance while drilling horizontal wells. The approach is based on the principles of integrating different-scale geological and geophysical studies. The lithological division of rocks was carried out, the saturation behavior and point-by-point interpretation of the data of geophysical methods of well logging (WL) were identified. 3D component models were built with taking into account the lithological features of the section using core sample studies. Effective models for the environment of sediments of interest were selected and petroelastic modeling was carried out.
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Abugharara, Abdelsalam N., Charles A. Hurich, John Molgaard und Stephen D. Butt. „Implementation of Circular Wave Measurements and Multiple Drilling Parameter Analysis in Rock Anisotropy Evaluation“. In ASME 2017 36th International Conference on Ocean, Offshore and Arctic Engineering. American Society of Mechanical Engineers, 2017. http://dx.doi.org/10.1115/omae2017-62088.
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A laboratory procedure has been developed to evaluate the anisotropy of Rock Like Material (RLM), granite, red shale, and green shale. This procedure involves detailed anisotropy evaluation steps through implementing circular ultrasonic wave velocity measurements, representing physical measurement and multiple drilling parameters (MDP), representing drilling performance. The physical tests involved circular pattern measurements of compressional and shear wave velocities, VP and VS, respectively. The drilling tests involved drilling samples of each rock in different a 25.4 mm Diamond Coring bit. The MDP included the study of the variations of Rate of Penetration (ROP), bit cutter Depth of Cut (DOC), Revolution Per Minute (RPM), and Torque (TRQ). The MPD were studied as function of orientations under atmospheric pressure. In addition to the physical and drilling evaluation, mechanical tests, such as Oriented Unconfined Compressive Strength (OUCS) were also used in rock anisotropy evaluation. Concrete with fine aggregate and Portland cement is used as RLM for much of the laboratory work. This material was cast into cylinders measuring 101.6 mm by 152.4 mm and 203.2 mm by 203.2 mm, from which NQ; 47.6mm core samples were taken. Coring was performed in three main orientations including 0°, 45°, and 90°. Characterization tests were performed on the RLM cores as they were conducted on the natural rock that included granite and red shale as isotropic and vertical transverse isotropic rocks, respectively. A fully instrumented lab-scale rotary drilling rig was used in conducting the drilling experiments. Details on the strategy for the tests on the anisotropy evaluation with results from laboratory work on natural rocks and RLM are reported. Result of the effect of shale anisotropy orientation on the drilling parameters that influence ROP as means of anisotropy evaluation are also, reported.
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Seaton, Simon, Thomas Jelley und Daphné Carthy. „Improving Employee Wellbeing through a Five-Phase Psychological Model to Reduce Risk and Improve Performance“. In SPE/IADC International Drilling Conference and Exhibition. SPE, 2021. http://dx.doi.org/10.2118/204036-ms.
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Abstract In its latest US Oil & Gas workplace safety report, the American Petroleum Institute (API) noted that the industry's incidence rate has decreased by 41% since 2008 due to an increased focus on the industry-wide goal of zero incidents (American Petroleum Institute, 2020). However, there continues to be a significant number of serious incidents directly related to human behaviours rather than a lack of control or processes. In a high-risk environment such as Oil & Gas sites, onshore or offshore, it is imperative to have a healthy workforce - both physically and mentally - and there is a link between worker wellbeing, stress, overall performance, and safety attitudes. Many segments of the Oil & Gas industry require workers to leave home and family for extended periods, and this can have a significant impact on an employee's psychological wellbeing. This paper aims to inform individuals and organisations so they can better understand the effects of the experience of being away and increase the chances of maintaining their workers’ psychological wellbeing. A five-phase model - from preparing to leave home through to being back at home - has been developed in consultation with academics, trade unions, expert insight from oil and gas, military and education sector perspectives. This model offers a new and practical way to think about and manage potential adverse impacts on psychological wellbeing while away in order to reduce risk. It was first set out by Seaton and Jelley (2015) and additional research has since been completed with new data that demonstrates the impact of the five-phase model. The five-phase model has been tested among international students at universities in the UK (Smith, Smith and Jelley 2018) and in 2019 among foreign workers at an on-shore location in the United Arab Emirates (UAE). Consistent with findings in the university context, the results of the latest field research suggest that greater use of strategies to cope with working away from home is associated with (a) greater positive wellbeing (happiness, life satisfaction) in life generally (b) a better quality of working life (c) more efficient operational performance.
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Mohammadlou, Mohammadhossein, Matthew Guy Reppert, Roxane Del Negro und George Jones. „THE IMPACT OF OVERBALANCED DRILLING FROM EXPLORATION/APPRAISAL WELLS TO FIELD DEVELOPMENT PLAN“. In 2021 SPWLA 62nd Annual Logging Symposium Online. Society of Petrophysicists and Well Log Analysts, 2021. http://dx.doi.org/10.30632/spwla-2021-0013.
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During well planning, drillers and petrophysicists have different principle objectives. The petrophysicist’s aim is to acquire critical well data, but this can lead to increased operational risk. The driller is focused on optimizing the well design, which can result in compromised data quality. In extreme cases, the impact of well design on petrophysical data can lead to erroneous post-well results that impact the entire value-chain assessment and decision making toward field development. In this paper, we present a case study from a syn-rift, Upper Jurassic reservoir in the Norwegian Sea where well design significantly impacted reservoir characterization. Three wells (exploration, appraisal, and geopilot) are compared in order to demonstrate the impact of overbalanced drilling on well data from both logs and core. Implications for reservoir quality assessment, volume estimates, and the errors introduced into both a static geomodel and dynamic reservoir simulation are discussed. This case study highlights the importance of optimizing well design for petrophysical data collection and demonstrates the potential for value creation. Extensive data collection was initially carried out in both exploration and appraisal wells, including full sets of logging while drilling (LWD), wireline logging, fluid sampling, and extensive coring. Both wells were drilled with considerable overbalanced mud weights due to the risk of overpressured reservoirs in the region. The log data was subsequently corrected for significant mud-filtration invasion, with calibration to core measurements guiding the interpretation. Geological and reservoir models were built based on results from the two wells, and development wells were planned accordingly. A thorough investigation of core material raised suspicion that there could also be a significant adverse effect of core properties resulting from overbalanced drilling. The implications were so significant for the reservoir volume that a strategic decision was made to drill a geopilot well close to the initial exploration well, prior to field development drilling. The well was drilled six years after the initial exploration phase with considerably lower overbalance. Extensive well data, including one core, were acquired. The recovered core was crucial in order to compare the reservoir properties for comparable facies between all three wells. The results from the core demonstrate distinctly different rock quality characteristics, especially at the high end of the reservoir quality spectrum. Results of the core study confirmed the initial hypothesis that overbalanced drilling had significantly impacted the properties of the core as well as the well logs. The study concluded that the updated reservoir model properties would significantly increase the in-place volumes compared to the pre-geopilot estimate. This study shows how well design adversely affected petrophysical measurements and how errors in these data compromised geological and reservoir models, leading to a suboptimal field development plan that eroded significant value. This example provides a case study that can be used to improve the well design so that petrophysicists and drillers can both be part of the same value creation result. Future work will include further laboratory investigations on the effects of high overbalanced drilling on core and possible “root causes” for compromised core integrity.
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Chen, Jianlin, Yanhua Yao, Yingbiao Liu, Zhaofei Wang, Craig Collier und Wenhuan Tang. „Valuable Cuttings-Based Petrophysic Analysis Successfully Reduces Drilling Risk in HPHT Formations“. In IADC/SPE Asia Pacific Drilling Technology Conference. SPE, 2021. http://dx.doi.org/10.2118/201064-ms.
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Abstract Cuttings data has always been neglected or forgotten as a source of information by many operators. In some areas, it is even common practice to throw away cuttings in order to reduce cost. However, cuttings data can yield a great amout of information to provide great value and support to drilling operations, as well as reduce potential downhole risks. This was evident in wells drilled in remote Western regions of China, where wells typically have high temperature high pressure (HTHP) formations with a true vertical depth ranging between 4000-7000 meters and target formation temperature between 150-160 degrees Celcius. Due to severe drilling conditions, the measurement tools of Logging While Drilling (LWD) and Measured While Drilling (MWD) are at high risk of running into holes. Even due to the high formations’ temperatures is over the bottom line of LWD and MWD tools, the sensors of LWD and MWD cannot work efficiently in such circumstances, increasing the drilling risk and expense. Thus, "blind" drilling is the most reasonable economical choice for local operators. Without sufficient real-time formations’ information, the drilling uncertainties dramatically increase. The fluid loss, pipe stuck, as well as drilling bit damages frequently occur. Currently, there is no successful well that accesses to the target reservoir. The data from the wireline logs and cores cannot be available, as the well is the first exploration well in the block; however, during drilling, only drill cuttings are available for peoples. The creative cutting-based petrophysics models are built for the formation analysis that is able to provide rock density, cuttings gamma, Delta Time of Compressional Acoustic (DTC), Unconfined Compressional Strength (UCS) Index, Caliper Index, Brittleness Index, and Hydrocarbon Index from the cuttings samples at the wellsite on a near-real-time basis. This data can help people quantitatively and qualitatively evaluate the downhole formations on a near-real-time basis and can help people to make a more reasonable decision, and therefore, reduce the drilling risk within a controlled level. The authors provide the several cases to study the cutting models into drilling events, and proves the models are consistent with log and core data, and match the drilling parameters and like ROP, and pumping pressure, as well as torque, and bit performance. LWD and MWD are unable to run into the hole due to high formation pressure and extreme risky hole. The field portable XRF instrument is applied, and the mineralogy and elements input into the models. The cuttings petrophysics analysis application can provide the valuable information for drilling engineers to drill the wells to TD.
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Scott, Dan E., und Marc R. Skeem. „Diamond Enhanced Shear Cutting Elements on Roller Cone Bits“. In ASME 2001 Engineering Technology Conference on Energy. American Society of Mechanical Engineers, 2001. http://dx.doi.org/10.1115/etce2001-17031.
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Abstract Polycrystalline diamond (PCD) cutters and drag bit designs have been substantially improved since their 1972 introduction, and PCD drill bits now are approaching the rolling cone tungsten carbide insert (TCI) market is terms of revenue size and have surpassed it in terms of economic impact on the drilling industry.1,2 These performance improvements have lead to a significant encroachment into the drill bit market built upon the breakthrough invention of the rolling cone bit by Howard Hughes Sr. Material and design improvements in the last decade, however, have now led to the successful application of patented shear cutting PCD elements as well as conventional diamond enhanced crushing style inserts on rolling cone bits. Diamond enhanced rolling cone bits are also a growth market for diamond elements in drilling. Failing rock in shear is a more efficient process than by crushing, but most cutting materials can not stand up to the forces generated in the shearing process as rock strength increases. To take advantage of the unique ability of the PCD cutter to shear rock efficiently, a concerted R&D effort supported by laboratory and field-testing led to the application of diamond as a shear cutting element on roller cone bits. A variety of rolling cone shear cutting elements have been developed and successfully commercialized in the last decade. This paper will discuss laboratory results and increased field performance achieved relative to conventional crushing style diamond and tungsten carbide inserts. The authors will document through case studies increases in rate of penetration (ROP), footage, overall durability, and gauge holding ability in addition to bearing/seal effectiveness that have further reduced drilling costs and served to increase usage of polycrystalline diamond elements on roller cone bits. These applications range from such diverse markets as high cost offshore North Sea, to low cost North American land operations.