Barrels Of Oil Research Articles

Petroleum Hydrocarbon Occurrence in Groundwater along the Trans-Niger Pipeline in Ogoniland, Rivers State, Nigeria

The Trans Niger Pipeline (TNP) commissioned in 1965 traverses Ogonil and along three (3) main corridors, covering a total distance of 62km and evacuates about 150 thousand barrels of crude oil per day to the Bonny oil Terminal. There have been several episodes of oil spillages along the TNP caused by pipeline failures and third-party interdiction; of which 84 oil spill incidents were reported between 2012 and 2014 alone, spilling a total volume of about 17,957bbls of crude oil into the environment. The incessant spilling of petroleum hydrocarbons along the pipeline Right-of-Way has polluted groundwater within these corridors and adjoining communities. This paper highlights the occurrence petroleum hydrocarbon contaminants and heavy metal complexes in groundwater within the corridors of TNP Right-of-Ways. Groundwater samples were obtained from 133 Geo-referenced boreholes and water wells within 200m swath of the TNP in Ogoniland. The results of laboratory analyses reveal the presence of Polycyclic Aromatic Hydrocarbons (PAHs) in concentrations ranging from 0.06µg/l to 1.0μg/l, Total Petroleum Hydrocarbons (TPH) ranged from 1.39μg/l to 4.34μg/l; in groundwater. Furthermore, the following heavy metals: Barium, Chromium, Cobalt, Cadmium, Lead and Nickel were also found in concentrations ranging from 0.11 µg/l to 19.5 µg/l. Hence, the concentrations of the aforementioned pollutants in groundwater along the TNP heightens our concerns for the safety of the inhabitants of communities who rely on water wells contiguous to the TNP for their everyday use. Chronic exposures to these toxins will ultimately have deleterious health effects especially for children.

Integrated Study of Production Decline Analysis and Streamline Simulation on Haripur Oil Field

In oil and gas industries there are available production data analysis tools and reservoir simulation techniques. Scientists and engineers use these tools and techniques to generate authentic and valuable information on the reservoir for planning and development. In this study production rate decline and streamline reservoir simulation are analyzed integrated way to determine the well life, flow rate, producible reserve, drainage volume and reserve. Well no SY-7 of Haripur oil field produced 0.531 million barrel of oil from 1987 to 1994. Exponential decline rate is matched with production profile and reveals well life of 10 years, producible reserve 0.7 million barrels. In addition, the drainage volume around the well is 158 million cubic feet estimated from the well life by using the streamline simulation, as well as the oil reserve 2 million barrels in the drainage volume is estimated. This reserve information carries value, authenticity and reliability for field development planning.
 Dhaka Univ. J. Sci. 67(1): 47-50, 2019 (January)

Polymer-Flood Field Implementation: Pattern Configuration and Horizontal vs. Vertical Wells

Summary A polymer pilot in the 8th Torton Horizon (8 TH) Reservoir in Austria showed promising results. The utility factors were 1.8 kg of polymer injected per incremental bbl of oil produced (polymer costs are EUR 1.74 to 3.48/kg). Furthermore, substantial incremental oil was produced, which might result in economic field implementation. The results triggered the planning for field implementation of polymer flooding. To optimize the economics of field implementation, a work flow was chosen ensuring that known uncertainties were covered. There were 1,200 geological models generated that cover a variety of different geological concepts. These geological models were clustered according to their dynamic response into 100 representative geological realizations, and then used for history matching. To screen areas of the reservoir that might benefit from polymer injection, probabilistic incremental net-present-value (NPV) maps were generated. Next, the well configuration was investigated using horizontal or vertical wells and the well distances. Afterward, operational parameters, polymer concentration, and duration of polymer injection were optimized for NPV. Finally, full-field simulation was performed to determine the cumulative distribution function (CDF) of incremental NPV. Applying the work flow to the 8 TH Reservoir in Austria led to the following results: Some areas of the reservoir were excluded from polymer injection because the P50 NPV map showed poor economics. Horizontal wells might lead to injection under matrix conditions, whereas vertical wells lead to injection under fracturing conditions for the conditions of the 8 TH Reservoir. In particular, the near-wellbore polymer rheology has a meaningful effect on injectivity. The NPV per reservoir area is higher for horizontal wells (EUR 43/m2) than for vertical wells (EUR 30/m2) because of the well cost vs. incremental recovery differences of the two configurations. The optimal well distance of the horizontal wells in the 8 TH Reservoir is 200 m for operational reasons. As operating parameters, a polymer concentration of 2,000 ppm and 8 years of injection were chosen to maximize NPV. The resulting CDF of incremental NPV showed a probability of economic success of 91% and an expected monetary value of EUR 73 million.

Geospatialization of Spilling Facility From Spdc 2015 Oil Spill Reports of The Niger Delta Region of Nigeria

A hundred and thirty two (132) Oil spill Incidents that occurred in year 2015 based on the existing SPDC Oil Spill JIV Reports were studied using GIS. The JIV reports were downloaded and the requisite information was acquired and incorporated into ArcMap10.2 and they were analysed to produce different maps. Result shows that about 18,233.04bbl of Oil was spilled and an area of 1,718,091.88m2 was impacted in year 2015.Pipelines account for 65.15% (86) of the spills, followed by flowlines 14.39% (19), Wellheads 13.63% (18) while others account for the rest. Pipelines are the most sabotaged Production Facility with 73.63 %( 81) of the Sabotage that occurred followed by wellhead13.63 % (15) and, flowline 10 % (11) while other Production Facilities account for the rest. This Study also shows that JIV Reports to an extent are a good and convenient tool for characterising Oil spills and the JIV culture should be encouraged. This study should be carried out on all JIV so that they are put in a Digital Format where they can be easily queried to produce the necessary information as needed.

Determinants of oil-spill cleanup participation following the Deepwater Horizon oil spill

BackgroundOn April 20, 2010, the Deepwater Horizon oil rig exploded, spilling over 4.9 million barrels of oil in the Gulf of Mexico over an 87-day period and developing into a long-term environmental disaster that affected people living in Gulf Coast states. Engagement of community members in recovery efforts is important for mitigating adverse effects of disasters and accelerating the rebuilding process for impacted communities; however, few studies have explored factors that determine participation in oil spill cleanups. MethodsWe analyzed data from the Gulf States Population Survey (GSPS) to study the determinants of participating in the Deepwater Horizon Oil Spill cleanup. The GSPS was a random-digit dialing survey conducted on 38,361 adults in counties and parishes in Alabama, Florida, Louisiana, and Mississippi impacted by the oil spill. Using survey estimation to account for the complex survey design, we estimated the probability of cleanup participation and used logistic regression to examine the association between sociodemographic factors and cleanup participation. ResultsApproximately 4.7% of residents in affected Gulf communities participated in the cleanup. Most participants were young, men, non-Hispanic white, and employed. Living in an affected coastal county was associated with higher odds of participation (unadjusted odds ratio [OR]: 1.69; 95% confidence interval [CI]: 1.28–2.24), as was having excellent or very good physical health (OR: 2.05; 95% CI: 1.11–3.81). Older persons were less likely to participate in the cleanup (OR for 65+ age group vs. 18–24 age group: 0.14; 95% CI: 0.05–0.36). ConclusionsUnderstanding the demographics of cleanup participants may help inform civilian recruitment for future oil spill responses.

Building Representations and Infrastructures in Places for Spaces

Unable to produce scales of one-to-one in places or spaces, people interact as they develop common representations, actions, and objects. In places, they can point to connect representations and objects. Places may be small spaces, but spaces can contain places and even more variations. Unable to name each variation, actors and analysts create abstractions. They might use a part to represent the whole, with miles of track for railroads, kilowatt-hours for electric power, and barrels of oil for energy. Some treat their representations as hegemonic, even true. However, dealing with social and material variations, actors and analysts represent, build, maintain, and repair combinations of cultures, economies, governments, and materials. Thus, railroads and power systems, like other technologies and infrastructures, do not design, build, or repair themselves. To resolve problems, people with relevant skillsets interact in places to create common representations, actions, and objects tying themselves and others together in spaces.

Is the oil industry able to support a world that consumes 105 million barrels of oil per day in 2025?

This paper investigates the significant risk of a supply crunch in the oil market by 2025 and beyond, given current pace of investment and growth of world demand. We focus particularly on today’s upstream sector and the challenges it faces in meeting the ever-increasing demand for oil. We then study different production scenarios for U.S. unconventional oil potential and draw conclusions on its potential capability to offset the weakening context of conventional oil supply (declining production, declining discoveries, insufficient investment, persistent geopolitical risks and environmental pressures). We conclude that with growing oil demand, the probability of an oil crunch by 2025 is far from null.

Green Energy and Environmental Protection in Modern World

The energy needs of the world are increasing every day, and the state in which we rely on the energy potential of fossil fuels such as coal, oil or gas is completely unsustainable. The rate at which oil is consumed is absurd. It makes a large part of fossil fuel cakes, but for each barrel of oil which is found to be consumed eight barrel. In the era of industrial revolution, the use of fossil fuels has increased rapidly as a initiator of changes. Considering that we live in a modern society where one of the imperatives represents new ways of obtaining energy, it is time to take responsibility for own actions and explore alternate ways of obtaining energy which can be collectively referred to call a Green energy. The term Green energy refers to all renewable energy sources. These are sources that can not be exhausted and give pure energy without the harmful consequences on the environment and our health. The aim of this paper is to briefly explain to readers what the production of new forms of energy means for the whole economy and what will happen if any form of environmental pollution occurs.

Cases and future developments of well stimulation approaches to siliceous shale reservoir

We have made continuous efforts to develop a middle mioccene siliceous shale distributed in northern Japan since 2012 with governmental supports. The shale formation is called as Onnagawa formation and is roughly estimated to have an order of hundred million barrels of oil as an original in-place. Although we have successfully recovered a certain amount of oil from Onnagawa shale, cost-effective and efficient production methods to exploit oil from Onnagawa shale are still unclear. In our project, two different stimulation approaches were tried: multi-stage hydraulic fracturing and acidizing.

The Paleozoic petroleum system in the north of Scotland – outcrop analogues

Abstract All of the components of an exhumed Devonian petroleum system occur in Orkney. These include a good quality mature source rock to bitumen-bearing sandstone reservoirs, with several separate accumulations that could have held about 1.88 billion barrels of oil. The exhumed system presents an excellent analogue for deeply buried petroleum systems offshore. Whilst lighter oils are now absent, reported oil shows occur, commonly associated with faults cutting the Eday Group. On Orkney, Middle Devonian source rocks (750 m thick) were thick lacustrine laminites (fish beds) representing some 30% of the sequence. RockEval and vitrinite analyses show the organic matter is good quality Type I and II and within the early oil window. These source rocks underwent burial until Permian inversion. Several exhumed reservoirs occur on Orkney in aeolian and fluvial sandstones with porosities from 15 to 25%. These reservoirs have been ‘breached’, losing the light-end hydrocarbons, leaving pore space oil stain and bitumen residues. Thin fluvial and sheet-floods sands found within the lake cycles have bitumen residues and provided connectivity between the thicker reservoir units. All types of trap are found including a major, broad anticline running north–south on Mainland Orkney and an unconformity with fault traps and pinchouts.

Oil as Currency: Venezuela’s Petro, a New ‘Oil Pattern’?

The socio-economic and political crisis that has been wreaking havoc on oil rich Venezuela since 2010, coupled with low oil prices since 2015, has generated hyperinflation on an enormous scale, rising to 500,000% in September 2018, and likely to reach 1,000,000% by the end of 2018. In response to its economic woes and hyperinflation, on February 20, 2018 the Venezuelan ‘Petro’ was officially born. The Petro, Venezuela’s new government-backed ‘cryptocurrency’, is a financial instrument whose value is pegged to the Venezuelan oil barrel and which attempts to create an alternative to the traditional currency system. While the idea appears novel – or to put it in ‘Venezuelan’ terms, ‘revolutionary’ – it is not. The Petro is a public debt instrument structured as a ‘cryptocurrency’ backed up by Venezuelan oil reserves and whose ‘intrinsic value’ is allegedly based on the Venezuelan international oil basket price as discretionarily decided by the Venezuelan Executive, not on trust of the currency itself or its demand or supply. The Petro’s relationship to Venezuela oil assets is important for the energy community not only due to its implications concerning Venezuelan oil reserves and infrastructure, but more so because the modality of this new ‘currency’ might be replicated by other raw-material dependent countries. They might do so to ‘mortgage’ their natural reserves to obtain financing by the sale of a raw-material pegged cryptocurrency. Much uncertainty accompanies the Petro and for very good reason. Hence, the aim of this paper is to present an academic analysis of the Petro. We discuss a number of critical aspects of the Petro, including an examination and clarification of its legal status, the regulatory regime is it subject to, the nature of the Petro (a currency or a debt), its relation to the future of energy markets, and risks associated with this creative measure.

Valuing Nature Waste Removal in the Offshore Environment Following the Deepwater Horizon Oil Spill

The offshore and deep-sea marine environment provides many ecosystem services (i.e., benefits to humans), for example: climate regulation, exploitable resources, processes that enable life on Earth, and waste removal. Unfortunately, the remote nature of this environment makes it difficult to estimate the values of these services. One service in particular, waste removal, was examined in the context of the Deepwater Horizon oil spill. Nearly 5 million barrels of oil were released into the offshore Gulf of Mexico, and 14 billion dollars were spent removing about 25% of the oil spilled. Using values for oil spillcleanup efforts, which included capping the wellhead and collecting oil, surface combustion, and surface skimming, it was calculated that waste removal, i.e., natural removal of spilled oil, saved BP over $35 billion. This large amount demonstrates the costs of offshore disasters, the importance of the offshore environment to humans, as well as the large monetary values associated with ecosystem services provided.

Geostatistical 3D geological model construction to estimate the capacity of commercial scale injection and storage of CO2 in Jacksonburg-Stringtown oil field, West Virginia, USA

As concerns around global warming increase, carbon capture, utilization and geological storage (CCUS) is a promising way to reduce the emissions of anthropogenic CO2 into the atmosphere. Sequestering the CO2 into depleted hydrocarbon reservoirs with associated enhanced oil recovery (EOR) is the most achievable approach under current economic constraints since it increases recovery of existing oil reserves, and bridges the gap between regional-scale CO2 capture and geologic sequestration. However, one of the challenges is the paucity of modern subsurface data required for adequate reservoir characterization and storage estimates. The Upper Devonian fluvial sandstone reservoirs in the Jacksonburg-Stringtown oil field in West Virginia, which have produced over 22 million barrels of oil since 1895, are ideal candidates for CO2 sequestration coupled with EOR. Reservoir storage capacity and oil recovery factors are keys for the evaluation of coupled CO2 storage and CO2-EOR process. Regression relationships between wireline logs and core measured data for porosity, permeability are constructed by artificial neural network and support vector machine in core-scale; then extended from core-scale to well-scale, where wells do not have porosity and permeability wireline logs; finally a 3D static geological model is generated based on the Random Gaussian Function simulation method and well-established variogram models generated by detailed data analysis. A static 3D reservoir model, which integrates detailed geological knowledge and existing legacy geological data from Jacksonburg-Stringtown oil field, is constructed to estimate theoretical CO2 storage capacity. Depending on the proposed 3D geological model, the best regions for coupled CCUS-EOR are located in southern portions of the field, and the estimated CO2 theoretical storage capacity for Jacksonburg-Stringtown oil field varies from 24 to 383 million metric tons. The estimated results of CO2 sequestration indicate that the Jacksonburg-Stringtown oilfield has significant potential for CO2 storage and value-added EOR.

Controls on organic matter distributions in Eocene Lake Uinta, Utah and Colorado

The Green River Formation deposited in Eocene Lake Uinta in the Uinta and Piceance Basins, Utah and Colorado, contains the largest oil shale resource in the world with an estimated 1.53 trillion barrels of oil in place in the Piceance Basin and 1.32 trillion barrels in the Uinta Basin. The Douglas Creek arch, a slowly subsiding hinge-line between the two basins, created separate deep depocenters, one in each basin with shallow water conditions near the crest of the arch. Lake Uinta was a saline lake throughout its history with a lower saline to hypersaline layer (monimolimnion) and an upper less saline layer (mixolimnion). Most of the organic matter in the Green River Formation was derived primarily from algae that lived in the photic zone of the lake and is very hydrogen-rich and oil-prone. In many modern large and deep lakes, rates of organic matter production are highly variable due to differences in nutrient supply. However, cyclonic circulation often leads to winnowing out of organic and mineral matter in the mixolimnion leading to organic matter and fine-grained mineral matter being deposited in increasing amounts toward hydro-dynamically dead zones in the center of the circulation producing concentric bands of increasing organic matter content. Organic matter transport through the dense, hypersaline monimolimnion may have been facilitated by low density organic matter attaching to more dense clay mineral particles. Most of the oil shale intervals deposited in Lake Uinta display similar patterns in their organic matter distributions, increasing in very regular fashion toward the central areas of the lake’s two depocenters. This concentric feature is particularly prominent in the most laminated oil shale zones. Here, we propose that cyclonic circulation was present in Lake Uinta. Each basin appears to have had its own circulation currents, separated by shallow water conditions near the Douglas Creek arch, and one hydrodynamically dead zone in each basin. Sediment gravity flow processes were also very active in some strata of Lake Uinta, leading to the reworking and re-depositing of sediments. Two general types of sediment gravity flows are recognized: (1) organic-rich sediment gravity flows that reworked and may have concentrated organic-rich material closer to the two deep depocenters, and (2) sandstone- and siltstone-rich organic-poor mass movement deposits that originated on marginal shelves. Mass movements could have been triggered by various natural processes and/or possibly by the movement of dense brines that evolved on marginal shelves and moved along the bottom of the water column toward the deep part of the lake. The uppermost, poorly consolidated sediment layer was incorporated in sediment gravity flows as they moved, and in many cases sediment gravity flows scoured down significantly into the more consolidated underlying sediment producing large rip-up clasts of laminated sediments. Truncation of more than 100 ft occurs at the base of a sequence of sediment gravity flows in one well, indicating a significant incised channel. Coarser-grained sediment gravity flows terminated before reaching the lake’s deepest areas, forming thick concentric buildups of organically lean sediment near the base of the marginal slopes. Intervals dominated by organic-rich fine-grained sediment gravity flows have tightly concentric bands of increasing organic matter toward the deepest parts of the lake and can be organically richer than the richest laminated intervals. There is some evidence that the hydrodynamically quiet zones did not always correspond closely to the deepest areas of the lake, extending in some cases into some shallower areas.

Military Use Of Environmental Degradation by Islamic State, Northern Iraq

Members of the co-called Islamic State of Iraq and Syria (IS) took control of Qayyara and the surrounding oil fields in June 2014. They were expelled by Iraqi forces in August 2016, but as they withdrew north, they created a complex battlespace igniting fires at the Al-Mishraq sulphur plant and at oil wells, as well as allegedly using chemical weapons. The fires were originally intended to deter coalition airstrikes, but later became a ground tactic to thwart the advance of US-backed Iraqi government and Peshmerga forces. Oil wells in the Qayyara and Najma oil fields were intentionally set alight and it took on average 30 days to put out a single well. Plumes from oil fires were observed in satellite images over 267 days, and it is estimated that 1,33 million barrels of oil burned. The market value of the sour crude burned was between $26,7 million and $45 million. Additionally, the fires denied IS earning between $105 000 and $472 000 from road tankerage of oil to Syria. The sulphur piles ignited by IS at the Al-Mishraq sulphur plant generated plumes of sulphur dioxide (SO 2 ) and hydrogen sulphide (H 2 S). Using ozone monitoring data, it is estimated that 83 461 metric tonnes (MT) of SO 2 were released into the atmosphere over six days. The market value of the combusted sulphur is estimated at $6,1 million. The fires set at oil wells and sulphur piles by IS caused significant lost revenue to the ‘caliphate’ but also amplified an existing humanitarian crisis in an environmentally degraded region. This was caused by a toxic legacy from previous conflicts, coupled with desertification and unsustainable agricultural practices. The fires and areas affected continued to have real health effects on civilians even after IS had been defeated. For humanitarian aid and military personnel who were exposed by being in the areas, the severity of the effect was dependent upon the level of toxicity and length of exposure. This highlights the need to monitor environmental degradation in conjunction with accurate and timely health and environmental threat assessment in conflict areas. These must continue after the fighting ends if the true effects are to be understood.

Technology Focus: Water Management (December 2018)

Technology Focus “Water, water, everywhere, And all the boards did shrink; Water, water, everywhere, Nor any drop to drink.”—Samuel Taylor Coleridge, The Rime of the Ancient Mariner Produced water has been an albatross around the neck of operators for a long time. It gets in the way of production by displacing the target oil, and it is filthy, requiring great expense to treat for reuse or disposal. Efforts to solve these challenges have been extensive and continue to evolve. These efforts can have a strong effect on the profitability of an operation. The authors of paper SPE 187624 claim that the amount of produced water could be in the region of 210 million B/D for every 75 million bbl of oil produced. “Many oil companies could almost be called water companies,” they write. Their paper presents efforts to increase oil production while disposing of produced water by using an inverted electrical submersible pump. These efforts resulted in the disposal of water through the same wellbore, reducing the expense of bringing it to the surface for treatment and of drilling disposal wells. Disposing of the produced water is only one factor that limits the profitability of operations. Treating the water before reuse or disposal also takes a substantial bite out of profits. Paper SPE 190272 examines an economical effort to desalinate produced water with the use of an electrochemical system with a resilient membrane. The membrane’s durability means that pretreatment of the water can be minimal, saving costs. In instances where polymer flooding is used, the membrane allows the polymer to remain in the desalinated water so that it can be used again. The cost savings from polymer reuse can be significant. Production facilities also suffer from the massive quantities of water produced. When produced water moves with the stream through a facility, it takes up precious space that could be used more profitably by oil. Paper SPE 187109 takes a look at one of the ways operators are looking to ease this bottlenecking problem. By partially processing the stream to remove water at the production manifold, more room is made for oil through transfer piping and in primary separation and floating storage facilities. The authors claim this has increased oil production by 80% and reduced the in-field transfer volume by 62%. For more solutions to the persistent problems of produced water, please see the papers listed as recommended additional reading and find more in the OnePetro online library (www.onepetro.org). Recommended additional reading at OnePetro: www.onepetro.org. SPE 187119 Employing Effective Water Treatment in West Texas To Mitigate Surface-Equipment Failures by Sarkis Kakadjian, Keane Group, et al. SPE 190129 Case Studies of an Effective Methodology To Collect Formation Water To Meet Regulatory Requirements for Formation-Water Sampling by V.H. Tran, Chevron, et al. SPE 188400 Successful Field Application of Bulk Water Removal Debottlenecks Declining Songkhla Marginal Offshore Fields, Extending Economic Life by Manuel De La Sota, CEPSA

The Economic Evaluation of the Efficiency of the ASP Chemical Flooding in DERO Field

In this research, economic evaluation of the efficiency of the ASP chemical flooding method applied on the oil-producing Jaribeh formation of DERO oil field was performed. The theoretical study firstly included complete explanation of objectives and justifications of the research, reference study related to the economic aspects of applying the mentioned method, overview of DERO oil field (lithostratigraphic, petrophysical, and depositional properties as well as reservoir indexes of Jaribeh reservoir in the mentioned oil field).The economic study however, included the following axes: Determination of sequence of chemical solutions and liquids proposed to be injected in the pilot area chosen for studying, determination of volumes of chemical solutions and liquids proposed to be injected in the pilot area, determination of the ideal batch of the ASP solution proposed to be injected in the pilot area, proposed scheme of the injection process, choosing a pilot in DERO field and determining its main reservoir characteristics, calculating volumes of chemical solution and liquids injected in the pilot area, calculating oil quantities expected to be produced from the pilot area as a result of applying the ASP flooding method, and calculating cost of chemical materials needed for the ASP flooding process in the pilot. As a result of this study, the additional quantity of oil produced by applying the ASP flooding method in the pilot was determined as well as the additional cost of an oil barrel resulted from using chemical materials in the mentioned flooding process that is (1.93 $/bbl).

Huff 'n' Puff Gas-Injection Pilot Improves Oil Recovery in the Eagle Ford

This article, written by JPT Technology Editor Chris Carpenter, contains highlights of paper SPE 189816, “Huff ’n’ Puff Gas-Injection Pilot Projects in the Eagle Ford,” by B. Todd Hoffman, SPE, Montana Tech, prepared for the 2018 SPE Canada Unconventional Resources Conference, Calgary, 13–14 March. The paper has not been peer reviewed. The Eagle Ford formation has produced approximately 2 billion bbl of oil during the last 7 years, yet its potential may be even greater. Using improved oil-recovery (IOR) methods could result in billions of additional barrels of production. While a number of companies have field-tested an IOR method called huff ’n’ puff gas injection, most of the published results are from laboratory and modeling studies. This paper evaluates the results of these field tests and discusses the potential of the huff ’n’ puff method in the formation. Introduction The Eagle Ford formation, formed during the late Cretaceous, is a laminated calcareous organic rich shale. The shale was deposited in a low-energy anoxic marine shelf environment, which allowed for rapid deposition and burial of abundant organic material. The Eagle Ford is divided typically into two sections: the Upper, which was deposited during a regional marine regression, and the Lower, which was deposited during a transgressional period and tends to have more organic-rich black shale. The Eagle Ford is laterally continuous and spatially extensive throughout much of southern Texas. The matrix permeability of the reservoir is low enough that typical hydrocarbon migration is restricted, causing the oil-rich rocks to be stratigraphically higher than the gas-filled ones. Results of Previous Huff ’n’ Puff Pilot Projects The huff ’n’ puff process involves injecting a miscible gas into a well and then, after some time has passed, producing back from that same well. Data have been collected on seven pilot projects in the Eagle Ford that have been completed during the last 5 years. Data from four of these seven are discussed in this synopsis. All of the pilots used hydrocarbon gas, but the composition of the gas varied across the locations. In addition, all of the field trials used a huff ’n’ puff injection scheme. Pilot A. The first pilot was a single isolated well where the nearest offset producers were more than 2 miles away. This provided some assurance that the injected gas would not migrate to other wells. The oil rates for the well indicated a positive response to the process. Each cycle increased the production rate to approximately half of the well’s initial rate. Once the oil rate began to drop, another injection cycle was started. This is encouraging because not only the first cycle but also subsequent cycles were able to increase production.

Effect of Deepwater Horizon Crude Oil Water Accommodated Fraction on Olfactory Function in the Atlantic Stingray, Hypanus sabinus

The Deepwater Horizon oil spill was the largest accidental marine oil spill in history, releasing nearly 5 million barrels of crude oil. Crude oil causes both lethal and sublethal effects on marine organisms, and sensory systems have the potential to be strongly affected. Marine fishes rely upon the effective functioning of their sensory systems for detection of prey, mates, and predators. However, despite the obvious importance of sensory systems, the impact of crude oil exposure upon sensory function remains largely unexplored. Here we show that olfactory organ responses to amino acids are significantly depressed in oil exposed stingrays. We found that the response magnitude of the electro-olfactogram (EOG) to 1 mM amino acids decreased by an average of 45.8% after 48 h of exposure to an oil concentration replicating that measured in coastal areas. Additionally, in oil exposed individuals, the EOG response onset was significantly slower, and the clearing time was protracted. This study is the first to employ an electrophysiological assay to demonstrate crude oil impairment of the olfactory system in a marine fish. We show that stingrays inhabiting an area impacted by an oil spill experience reduced olfactory function, which would detrimentally impact fitness, could lead to premature death, and could cause additional cascading effects through lower trophic levels.

New Surfactants and Cosolvents Increase Oil Recovery and Reduce Cost

Summary Scientific understanding of how the molecular structures of surfactants and cosolvents affect microemulsion properties greatly speeds up the process of arriving at optimal chemical formulations for enhanced recovery of a specific crude oil. With the main emphasis on reducing the chemical cost of the formulations, novel surfactants and cosolvents have been developed and shown to have superior performance. We have synthesized and tested surfactants with different hydrophobe sizes and structures varying from ultrashort to large to satisfy a variety of crude-oil requirements over a wide range of reservoir conditions. The cosolvents and surfactants with ultrashort hydrophobes offer advantages such as short equilibration time for the microemulsion formation and lower microemulsion viscosity. Chemical formulations developed using these chemicals have shown excellent performance with very low cosolvent and surfactant retention in cores. Low retention means less chemicals can be used to recover each barrel of oil from the reservoir. These chemicals can be made commercially at low cost. Through use of these new developments, the chemical cost per barrel of oil is low enough to be economically viable, even at low crude-oil prices.