Temizel, Cenk (Aera Energy) | Balaji, Karthik (University of North Dakota) | Canbaz, Celal Hakan (Ege University) | Palabiyik, Yildiray (Istanbul Technical University) | Moreno, Raul (Smart Recovery) | Rabiei, Minou (University of North Dakota) | Zhou, Zifu (University of North Dakota) | Ranjith, Rahul (Far Technologies)
Due to complex characteristics of shale reservoirs, data-driven techniques offer fast and practical solutions in optimization and better management of shale assets. Developments in data-driven techniques enable robust analysis of not only the primary depletion mechanisms, but also the enhanced oil recovery in unconventionals such as natural gas injection. This study provides a comprehensive background on application of data-driven methods in oil and gas industry, the process, methodology and learnings along with examples of data-driven analysis of natural gas injection in shale oil reservoirs through the use of publicly-available data.
Data is obtained and organized. Patterns in production data are analyzed using data-driven methods to understand key parameters in the recovery process as well as the optimum operational strategies to improve recovery. The complete process is illustrated step-by-step for clarity and to serve as a practical guide for readers. This study also provides information on what other alternative physics-based evaluation methods will be able to offer in the current conditions of data availability and the understanding of physics of recovery in shale oil assets together with the comparison of outcomes of those methods with respect to the data-driven methods. Thereby, a thorough comparison of physics-based and data-driven methods, their advantages, drawbacks and challenges are provided.
It has been observed that data organization and filtering takes significant time before application of the actual data-driven method, yet data-driven methods serve as a practical solution in fields that are mature enough to bear data for analysis as long as the methodology is carefully applied. The advantages, challenges and associated risks of using data-driven methods are also included. The results of comparison between physics-based methods and data-driven methods illustrate the advantages and disadvantages of each method while providing the differences in evaluation and outcome along with a guideline for when to use what kind of strategy and evaluation in an asset.
A comprehensive understanding of the interactions between key components of the formation and the way various elements of an EOR process impact these interactions, is of paramount importance. Among the few existing studies on natural gas injection in shale oil with the use of data-driven methods in oil and gas industry include a comparative approach including the physics-based methods but lack the interrelationship between physics-based and data-driven methods as a complementary and a competitor within the era of rise of unconventionals. This study closes the gap and serves as an up-to-date reference for industry professionals.
The PDF file of this paper is in Russian.
In recent years the task of development for an unconventional oil deposits (like a shale oil, heavy oil sands, tight oil, etc.) became highly important. On of such task is the development of Bazhenov formation reservoir containing large amounts of kerogen. Application of a thermal and gas impact (TGI) considering as an effective solution to this problem by pumping air under high pressure into the producing formation leading to the emergence of a highly miscible with the oil displacing agent that is formed by in-situ oxidation and thermodynamic processes. A thermal gas impact by pumping air under the high pressure into the producing formation is considered as an effective solution of this problem causing the moving hearth of burning due to in-situ oxidation and thermodynamic process. In the anoxic zone of the coking area ahead of the combustion front, which is characterized by increased temperatures, the kerogen is exposed to low temperature pyrolysis. To determine the optimal conditions for forming the maximum amount of liquid hydrocarbons due to pyrolysis reaction of solid organic a series of experimental studies of the pyrolysis kerogen-containing rocks in thermochemical reactors for the Bazhenov formation had been carried out in VNIIneft JSC. Besides, for the qualitative evaluation of the obtained liquid phase from the kerogen a complex study for determination the heat release in differential scanning calorimeter (DSC1) had been carried out. As a result of these studies it has been shown that the possibility of separating the organic matter of the Bazhenov formation from its mineral composition by using low temperature pyrolysis (350-450°C) with formation of liquid hydrocarbons observing in the whole studied temperature range and it`s reduction with increasing duration of the experiment as a result of further destruction. Comparison of the dissipation curves for the rock samples before and after experiments in the thermo-chemical reactor shows the number of additionally obtained liquid phase due to the pyrolysis of kerogen. Based on the results of the studies a light hydrocarbon components are mainly occurring at temperatures of 350-400°C. It should be noted that while the temperature reaching 400°C and above a secondary-cracking processes are overlaying with pyrolysis with a formed thermo-bitumen initiating to decompose into volatile components and coke which may cause clogging of the pores and channels in the rock.
На протяжении последних лет задачи разработки месторождений нетрадиционных запасов нефти (сланцевая, высоковязкая нефти, нефтяные пески, нефть низкопроницаемых пород и др.) стали крайне актуальными. Одной из таких задач является разработка пластов баженовской свиты, обладающих высоким нефтематеринским потенциалом по степени обогащенности органическим веществом. Эффективным решением данной проблемы считается применение термогазового воздействия (ТГВ) путем закачки воздуха под высоким давлением в продуктивный пласт, приводящей к возникновению движущегося очага горения за счет протекания внутрипластовых окислительных и термодинамических процессов. В бескислородной зоне коксования перед фронтом горения, характеризующейся повышенными температурами, кероген подвергается низкотемпературному пиролизу. Для определения оптимальных условий образования максимального количества жидких углеводородов вследствие протекания процесса пиролиза твердого органического вещества в АО «ВНИИнефть» проведена серия экспериментальных исследований пиролиза керогеносодержащей породы баженовской свиты в термохимических реакторах. Кроме того, для качественной оценки полученной жидкой фазы из керогена выполнен комплекс исследований по определению тепловыделения на дифференциальном сканирующем калориметре (DSC1). Показана возможность выделения твердого органического вещества из породы баженовской свиты с помощью низкотемпературного пиролиза (350-450 °С), причем образование жидких углеводородов наблюдается во всем исследуемом температурном диапазоне, а с увеличением продолжительности эксперимента снижается в результате дальнейшей деструкции. Сравнение кривых тепловыделения для образцов породы после экспериментов в термохимическом реакторе и вторичной экстракции позволяет определить количество дополнительно полученной жидкой фазы, образовавшейся в результате пиролиза керогена. Исходя из результатов исследований, легкие углеводородные компоненты выделяются в основном при температурах 350-400 °С. Отмечено, что при достижении температуры 400 °С и более накладываются процессы вторичного крекинга, причем образованный битумоид начинает разлагаться на летучие компоненты и кокс, что может привести к кольматации пор и каналов в породе.
The rising level of industrial activity in the Barents Sea region will result in more SAR operations. Oil and gas companies develop their own emergency response organizations in order to obtain the governmental permits required to operate. Where commercial shipping and fisheries are concerned, emergency response operations will depend on the availability of governmental resources and vessels of opportunity when an accident occurs. Low sea and air temperatures require rapid response in the event of a maritime emergency.
Ghanaians have been concerned about the pollution of the surrounding waters of the country since the start of offshore exploration activities (
According to R.L Petrusac et al(2000), produced water is one of the largest streams of waste from offshore facilities. In order to identify gaps in existing effluent analysis requirements, this paper assessed produced water, from FPSO Kwame Nkrumah, a base case scenario of current analysis requirements in Ghana was assessed, selected countries; US, UK, Norway and Nigeria analysis requirements were also examined to bring out the gaps and a guideline was drafted for use by stakeholders.
Taking a look at analysis required in the various countries compared with Ghana, it was seen that the requirements varied from one country to the other. The only requirement running through all was the oil and grease requirement. This was accepted by all as being an important value to be monitored. A guideline was developed to include all other analysis in the other countries which were not currently being monitored in Ghana. This guideline will be useful to stakeholders interested in finding out produced water effluent composition in order to prevent pollution and also advise on important analysis required to be carried out.
Due to the complexities involved in the analysis of micro- and mesoporous gas shale, a combined theoretical and experimental approach has proven to provide increased insight into the adsorption characteristics of methane (CH4) and carbon dioxide (CO2). Pore characterization techniques are used to provide information for theoretical modeling efforts, such as pore volume and pore size distribution (PSD). Idealized powdered shale sorption isotherms are created by varying incremental amounts of kerogen, illite, quartz, and calcium carbonate (CaCO3). The kerogen and illite have been shown to be the most vital for micropore measurements. The kerogen was obtained from Silurian shale, while Green River illite was used for the clay component and the rest was composed of equal parts by weight of silica (SiO2) to represent quartz and CaCO3 to represent the carbonate components. Baltic, Eagle Ford, and Barnett shale sorption measurements were used to validate the idealized samples. The idealized and validation shale sorption isotherms were measured using low-pressure N2(77K), Ar (87K) and CO2 (273K) adsorbates on a Quantachrome Autosorb IQ2 instrument. A subset of these samples was also measured using CO2 and CH4 adsorbates under subsurface temperature and pressure conditions using a Rubotherm magnetic suspension balance. The shale samples were processed using outgassing temperatures that did not affect the structures of kerogen and illite, while removing adsorbed gas species, such as H2O and CH4. This data lends itself toward the development of predictive models weighted and scaled by the percentages of these essential shale components to provide accurate gas-in-pace estimates of both CH4 and CO2.
A major part of world’s oil and gas reserves are located in Arctic and Subarctic seas, such as Sakhalin fields in Okthosk Sea as well in Chuchki Sea, Beaufort Sea Alaska. Year around operations in these areas results increasing need for special designed icebreaking offshore support vessels and tankers. Important characteristic of these vessels is the capability in ice managent duties.
Azimuth thruster offers great flexibility in different ice management using the thruster wake and propeller close contact with ice. Electric propulsion with Azipod propulsors has been used in such vessels with good success for many years and the system itself has shown to be reliable and very good characteristics when operated in ice. In Sakhalin region there has accumulated experience from 7 icebreaking vessels with ABB electric propulsion many equipped with Azipods. Recently two new icebreaking vessels with Azipod have been built for Arkutun-Dagi field. Electric Azipod propulsion system have been playing an important part in several arctic ship projects making the demanding projects technically and economically feasible. In this paper will be presented characteristics as well some full-scle test results where Azipod units are used in ice management type operations.
Stein, H. J. (AIRIE Program, Colorado State University, USA) | Hannah, J. L. (AIRIE Program, Colorado State University, USA) | Yang, G. (AIRIE Program, Colorado State University, USA) | Galimberti, R. (Eni E&P, San Donato Milanese, Italy) | Nali, M. (Eni E&P, San Donato Milanese, Italy)
To test the effectiveness of the Re-Os system for tracing source rocks and marking the time of maturation and expulsion, we examined a natural system in which key variables are controlled. Hydrocarbon source rocks (Late Ordovician Fjäcka shale) and adjacent, partly contemporaneous reservoir rocks (carbonate mounds) are exceptionally well exposed in quarries, drill core and outcrop in the Siljan area of central Sweden. At 377 Ma, a giant meteorite impacted the region heating Early Paleozoic sections, including immature Ordovician-Silurian hydrocarbon source rocks. Oil seeps and asphaltene coatings in carbonates just outside the Siljan impact crater attest to hydrocarbon maturation associated with the impact. The size of the impact supports elevated temperatures over a maturation-migration period of 10 to 1000 Ka, not unlike that for some sedimentary basins. The Siljan "field laboratory?? permits sampling of source rock and migrated oils in immediately adjacent units - uniquely, with the time of maturation temporally pinned by the bolide impact. Through Re-Os analyses of the source rock and analyses of the oil it generated, we found the Re-Os isotopic system to be intact at two of three shale localities, obtaining the expected late Ordovician and early Silurian depositional ages. In contrast, the Re-Os isotopic compositions and erratically varying Os concentrations derived from the oil seeps suggest infusion of shale-derived oil with Os derived from the bolide. Thus, we show that shales generally retain their Os isotopic systematics, even under extraordinary circumstances, whereas small quantities of migrating oil at Siljan were easily overwhelmed by the strong Os isotopic signature carried by the bolide.
A unique opportunity at the Siljan impact site
Seventy percent of meteorites leave their mark in the sedimentary record, yet little is known about the response of sedimentary targets on impact. The consequences of meteorite impacts for the continental and oceanic sedimentary record inform questions of climate change and mass extinction, both critical concepts to understanding deposition of source rocks. For two reasons, application of the Re-Os isotopic system to impacted black shales provides a unique opportunity to examine hydrocarbon maturation and migration. First, the extreme contrast between Re-Os concentrations and Os isotope compositions in sedimentary versus extraterrestrial reservoirs readily permits detection of both end members. Second, maturation and migration are nearly coincident and reduced to a geologic instant at the moment of impact. That moment is a well-dated heating event at 377 Ma - the impact age of the giant Siljan bolide smashing into the Late Devonian (Frasnian) seabed.
Re-Os and hydrocarbons
Key inputs for modeling hydrocarbon systems are identity of source rock(s) and the maturation and migration time(s). Typically, biomarkers are used to link migrated hydrocarbons to specific source rocks. This tool may be compromised by biodegradation of the oils, however. Time of maturation is generally estimated from models of burial history and is therefore dependent on estimates of biostratigraphic ages, sediment thickness and compaction history, and subsidence rates. Re-Os geochemistry overcomes some of these limitations and assumptions, serving as an intact tracer with a clear time component; biodegradation does not appear to compromise Re-Os systematics.
According to the European Wind Energy Association (EWEA) in the first six months of 2012, Europe installed and fully grid connected 132 offshore wind turbines, with a combined capacity totalling 523.2 MW. Overall, 13 wind farms were under construction. Once completed these wind farms will account for 3,762 MW. Europe is therefore the industry leader since the initiation of offshore wind turbine development. Most of the projects have been limited to less than 30-m deep waters in the North and Baltic Seas. However, planned offshore wind farms in Germany will be located in water depths up to 40 m. Future offshore sites in the UK include water depths to about 65 m. Offshore wind farm systems today use three types of foundation: monopile structures, gravity structures or multi-pile structures. They are economic in relatively shallow water depths. Current monopile diameters range between 4 and 6 m, wheres as piles for jacketed structures are smaller (i.e. between 2 and 3m). They are relatively easy to install, for instance, in soft clayey soils or sandy layers. There are, however, several situations where the pile driving installation is not suitable. The department of maritime technologies of BAUER Maschinen GmbH already developed other offshore foundation installation methods based on its know-how in the onshore foundation engineering practice.
According to the IREA report, offshore wind farms are at the beginning of their commercial deployment stage. Offshore turbines are designed to resist the more challenging wind regime offshore and require additional corrosion protection and other measures to resist the harsh marine environment. The increased capital costs are the result of higher installation costs for the foundations, towers and turbines, as well as the additional requirements to protect the installation from the offshore environment. The most obvious difference between onshore and offshore wind farms is the foundations required for offshore wind turbines. These are more complex structures, involving greater technical challenges, and must be designed to survive the harsh marine environment and the impact of large waves. All these factors and especially the additional costs of installation mean they cost significantly more than land-based systems. Besides, Moving offshore will allow the use of very large wind turbines capable of supplying typically 3.5 MW (although this will probably increase with time), installed in farms of 50 or more turbines. In contrast to typical oil and gas structures used offshore, for a wind turbine the foundation may account for up to 35% of the installed cost (Byrne and Houlsby 2003). These structures will be large; the turbine hub for a proposed 3.5 MW machine is expected to be some 90 m above the sea floor, with the rotor diameter likely to be of the order of 100 m. Initially the structures were installed in relatively shallow water (5-20 m in depth). While installing structures offshore is hardly novel, these structures are different from typical offshore structures (usually oil and gas structures) in two respects, both related to the applied loads on the structure and hence on the foundations (Byrne and Houlsby 2003). According to EWEA 270 foundations (141 or 109% more than the same period last year) were installed during the first six months of 2012 in 10 wind farms: Thornton Bank 2 (Belgium), Lincs, London Array, Sherigham Shoal, Gwynt y Môr, Teeside (UK), Anholt, Avedore 2 (Denmark), BARD Offshore 1 and Riffgat (Germany).Currently in Germany foundations depth ranges between 20 and 40 m, according to the BSH (Federal Maritime and Hydrographic Agency) at the current state. Turbine sizes range betwenn 3 and 5 MW.
Shale - No abstract available.
It is now possible to relate most oil and gas reserves to six stratigraphic black shale formations which include the majority of the world's oil and gas source rocks (Ulmishek and Klemme, 1990). From 1997 the US Dept of Energy attempted to predict the activity of NORM and other factors which may affect the activity and / or occurrence of NORM in E&P production operations (Chriss 2002). Black shales are the source rocks for petroleum trapped within Uranium deposits (IAEA 2009).
According to current ideas kerogen† is the organic constituent of sedimentary materials that is associated with petroleum formation. Kerogen is considered by petroleum geologists as being of two different varieties: humic kerogen associated with poor oil sources and sapropelic‡ kerogen, related to subaqueous sediments and associated with rich oil sources. Oil and gas is formed by the thermal cracking of organic matter (kerogen) trapped in sedimentary rock.
Two hypotheses regarding NORM in E&P production operations need to be considered. The first hypothesis is that NORM is produced by locally high U and Th concentrations in the reservoir rocks. If this is generally true, NORM scale will be largely controlled by the geological formation and lithology. The second hypothesis is that NORM is released from ordinary geological media during normal geological processes. If this is generally true, the potential for NORM scale
precipitation may be predicted largely from basin setting and history.
A worldwide survey comprising a comprehensive review and detailed analysis of reported NORM activity in oilfield scales has now determined which of these hypotheses prevails. For the first time management will now have the ability to predict the magnitude of NORM in E&P facilities worldwide.