bluuebunny/crossref_metadata_2025 huggingface dataset:
Balancing Sustainable Offshore Production with Onshore Social and Environmental Issues in Central California
Authors: Hargis P. D.
Published: December 2007

The topic of sustainable development is often raised as an issue when major oil and gas projects are proposed in developing countries. In most cases, this issue is raised by well-intentioned government bodies or private organizations focused on environmental and social protection. These Governments and Non-Governmental Organizations (NGOs) frequently refer to the finite nature of the petroleum resource and inevitable decline in production from an individual field as justification for cautious and controlled development, or no development at all. The issue of sustainable development is better addressed by expanding our view of the development area to include an entire resource basin, or even multiple basins in a specific region. The California Offshore Oil and Gas Energy Resources Study, which was sponsored by the Pacific OCS Region of the U.S. Department of Interior, Minerals Management Service with support from offshore oil and gas leaseholders and the Western States Petroleum Association, offers one approach to such an expanded view. That study addresses a resource area with an over 100-year-long history of offshore production, substantial remaining oil and gas resources1,2, and an active network of environmental protection NGOs. The technical approach applied in this study involved a combination of production projections, resource potential, activity estimates, and infrastructure capacity determinations to define the characteristics of different development scenarios and identify the maximum sustainable level of development in balance with community constraints. This effort succeeded in identifying a sustainable level of development consistent with recent and historic levels of industrial activity, and provides a model that could be applied to other regions. The reaction of some members of the local community to the results of this study suggests that the topic of sustainable development may be more complex than it first appears, and its categorization as an environmentally and socially preferred result is an oversimplification of this topic.
Controlling Remediation Costs by Source Removal and Natural Attenuation
Authors: Miller John A.
Published: December 2007

Remediation of releases of petroleum hydrocarbons and chlorinated hydrocarbons in soil and groundwater has been a costly and time-consuming process. Alternative methods of treating impacted soil and groundwater have accelerated the rate of expenditure without a corresponding acceleration in the rate of environmental cleanup. Active treatment of groundwater is required if contamination will reach and impact a receptor. If there is no receptor, more thoughtful planning can lead to lower cost activities.

This paper describes the experiences of our oilfield service firm in three phases from 1988 to the present and focuses on their efforts in remediation of chlorinated hydrocarbon compounds in groundwater. The initial phase involved removing underground storage tanks and recognizing the problem. The second phase consisted of installing innovative and traditional remediation systems, then evaluating the remediation systems. The final phase was developing a natural attenuation protocol, implementing the protocol and measuring results. The natural attenuation protocol is defined and the parameters to be measured are described in this section of the paper.
Ekofisk I Disposal – Impact Assessment
Authors: Nesse S. , Brun B. T. , Kvendseth S.
Published: December 2007

Following a very thorough planning process, initiated in the early nineties, the cessation plan for the Ekofisk I field was submitted to Norwegian authorities October 1999. Ekofisk I, containing some 14 steel jacket based and one concrete based installation, some 40 pipelines as well as some drill cuttings piles, is the most complex field ever being planned for cessation world-wide to date. The planning process has in most ways been pioneer work, both in a Norwegian and international context. In this paper a discussion and presentation of the planning process is given. As part of the planning, the work related to the Environmental Impact Assessment (EIA) plays an important role with regard to objectivity of technical assessments and openness to society and the public in general. In many ways this EIA has set the standard for future EIA's addressing offshore field cessation, both with regard to methods applied and presentation of findings. The paper presents the major steps in the EIA process, gives an introduction to methods applied, and presents the most important results from the objective assessment of the disposal alternatives.

Finally, the recommended solution is presented, including a discussion of criteria applied in reaching the decision, justification for the recommendation and a presentation of impacts related to the recommended solution.
Bioavailability to Fish of Hydrocarbons Contained in Oil Droplets or Dissolved in Water
Authors: Skadsheim A. , Sanni S. , Cova C. A. , Gaudebert B.
Published: December 2007

The fate of hydrocarbons (HC) in discharged produced water is complex. In risk assessment models such as DREAM, it is essential to focus on the critical fate processes and omit less important ones. To improve our discrimination capability, we examined the bioavailability of polyaromatic carbons (PAC) and n-alkanes. Sheepshead minnows (Cyprinodon variegatus) were exposed to two test solutions: sequentially produced batches of a water soluble fraction (WSF) of oil, and an oil dispersed mechanically and supplied continuously at a high and a low dose. The objective was to achieve a WSF where sum PAC was between that of the low dosage (LD) and the high dosage (HD) of oil droplets. If uptake was proportionally similar along the concentration gradient, it may not be necessary to discriminate between water dissolved and oil droplet bound hydrocarbons in the model. For the most water soluble PAC, uptake in fish was comparable for WSF and oil droplets. For the less water soluble and larger molecular PAC, fish uptake was lower from oil droplets than from the WSF. HC need more time to leave oil droplets as molecular size increases, but also the number of compartments (water, oil droplets, fishes) present in the test system influenced uptake in the fish. The n-alkanes were absent in the WSF and the fish, and only found in the oil droplets. We propose that treating all HC as water dissolved is a very conservative approach that also requires less data for the model development.
Cost-Benefit Decisions Integrating Business and Eco-Management Results in Best Environmental Practice in Drilling and Well Operations
Authors: Paulsen J. E. , Jensen B. , Løklingholm G. , Saasen A.
Published: December 2007

This paper presents a strategy designed to meet the requirements of responsible business management compliant with current environmental legislation. It is shown how it facilitates profitable returns like cost savings and reduction in environmental loads.

A total fluids management (TFM) concept for drilling and well operations was developed to merge the interests of reduced costs and environmental impact, and the suppliers need for business incentives. Integration of best available technology, waste minimisation programs, benchmarking and contractual incentives for recycling of material are key elements of the concept. Realistic hopes proposed operational cost cut > 10% without compromising environmental goals or corporate business management. Presented data show a cost reduction of 16.8% in drilling operation. Other benefits are also presented and discussed. The success is ultimately linked to the close team working across the traditional service lines of fluids; solids control waste management, associated waste processing and treatment, as well as logistics.

The TFM concept is proposed as a business standard. It is a core element that can be extended to incorporate different operators and fields in the same region, thus facilitating the greatest potential for achieving the full benefit of large-scale operation and its inherent reduction of total environmental impacts
A Field-based Health Reporting System
Authors: Moreau Jean-Marie , Huebner Wendy W.
Published: December 2007

In many areas of the world the burden of endemic disease can impact oilfield operations. In order to better manage health support in high-risk, remote locations, there is a need to collect reliable and meaningful health event data. A field based health reporting system is critical for evaluating impacts on operations
Application of Reedbed Technology in Production Water Management
Authors: Gurden Catherine , Cramwinckel Joppe
Published: December 2007

PDO currently produces some 450,000 m3/day of water as an associated co-product of its oil output of 135,000 m3/day. The volume of this production water has been steadily increasing over time and is predicted to rise to above 900,000 m3/day by the year 2009 (Figure 1). In 1998 approximately 40% of the produced water was injected by PDO for reservoir pressure maintenance. The remaining volumes were disposed of into shallow and deep reservoirs.

PDO is predicted to spend some US$130 mln on produced water management over the coming 8 years of which US$120 mln is related to disposal into deep reservoirs. Understandably significant effort is invested in exploring alternatives to Deep Water Disposal. The lifecycle cost of DWD over a 20-year period has been calculated at PV US$ 0.13/m3 of water disposed. This lifecycle cost is used to benchmark alternatives. To date conventional water clean-up technology has been estimated as having a lifecycle cost of between PV US$0.3-US$0.5/m3 water treated.

During 1998, and with input from Shell Research Thornton, a new technology to the oilfield industry, termed reed bed technology was identified as an attractive produced water clean-up technology. Reed bed technology is a phytoremediation process, which promotes degradation of hydrocarbons and sorption of heavy metals while consuming some of the produced water.

An experimental facility, 800 m2 capable of treating 20 m3/d of produced water, was commissioned at the Desert Agriculture Project in January 1999. The results, to date, have been encouraging with >98% removal of hydrocarbons from the Marmul production water. Heavy metal sorption is still under investigation. Evapotranspiration rates are in line with predictions with a 50% water volume reduction across the bed.

Based on the success of this experimental facility a larger pilot, 6 hectares treating 3,000 m3/d of produced water, has been constructed and is being commissioned at Nimr. Based on the pilot costs, a lifecycle cost estimate for Reed Bed technology is estimated at PV US$0.07/m3 water. After 18 months operation, the time taken for system to reach optimal capacity, a decision will be taken on whether Reed Bed technology can be successfully applied in PDO.

The challenge for PDO is to find a value crop that can be grown with the reed bed effluent to offset the capital investment and provide opportunities for the local community.
Reduction of Emissions to Sea by Improved Produced Water Treatment and Subsea Separation Systems
Authors: Wolff Erik A.
Published: December 2007

Oil and gas production is an activity that causes emissions to air and sea. The emissions range from traces to catastrophes, toxic to harmless and from rare to continuous. The production facilities are widely different in size, location and operating traditions. This makes it difficult to standardise "best industry practice". Recent advances in process equipment hold promise for reducing emissions to sea, primarily of oil. This article presents these advances together with relevant statistics and data from Life cycle assessments.
Creating and Measuring an Effective HSE Management System -- A Study of the Effectiveness of a Management System in the Gulf Coast as Measured by an Advanced Safety Audit
Authors: Adams Bruce , Nims David
Published: December 2007

Health, safety and environment (HSE) management systems are increasingly common as operating and service companies follow the recommendations of the International Association of Oil & Gas Producers (formerly E & P Forum) and establish a structured system for managing HSE. The elements of a management system can be described as empty shells that, when filled with the proper tools, have a significant impact on reducing incident rates in companies that implement the system. The Schlumberger HSE management system follows the structure of the seven basic elements of the OGP model, but it includes one additional element, contractor and supplier management. As written, the management system has little impact on the safety performance of the company. It is the proper implementation of the programs, standards and policies making up each element that allows a company to provide a cohesive, structured system to ensure risk reduction, loss prevention and continuous improvement.

Schlumberger Gulf Coast operating locations have transformed the abstract structure of the Schlumberger HSE management system document into reality through the implementation of company-wide guidelines and programs, supplemented with local standards. In several instances, these programs draw from the best management practices of major operating companies within the Gulf Coast. To verify the effectiveness of the system, BP Amoco conducted Advanced Safety Audits in three Schlumberger operating locations.

To understand an HSE management system, each element must be examined from a standpoint of what the book says as well as what is actually taking place in a location to make that element work. The Advanced Safety Audit process used by BP Amoco is an effective tool for accomplishing this task. All elements of the management system, starting with the most important, commitment and leadership, are evaluated to assess the real effectiveness of a HSE management system.

Finally, no system can be considered truly effective unless it is supported by results. The improvement in the Schlumberger Gulf Coast HSE performance over the past 12 months is directly attributable to the enthusiastic implementation of this management system by employees of Schlumberger Gulf Coast operating locations.
Environmental Management – An Oilfield Service Company Experience in Nigeria
Authors: Fayiga Adedoyin , Ofunne Goodwill C.
Published: December 2007

Management for continual environmental performance in a developing country can be a challenging affair. Multiple statutory regulations, standards and guidelines frequently are conflicting at the various tiers of government. Prevalent and increasing community sensitivities and awareness, and proximity with other industries that may not be at the same level of environmental practices, all combine to make the achievement of a good environmental performance a formidable task. Statutory enforcement agencies usually focus their efforts on the multinational companies, and this may account for a significant amount of lost time.

Consequently, the adaptation of an Environmental Management System (EMS) that is simple, flexible, continuous, and auditable offers a suitable solution to the inherent environmental problems in a developing country.

This environmental management system requires the development of a site-specific system (based on corporate policy, structure, personnel training, measurement, recording, monitoring, management review and audit systems) with clearly defined work scope to ensure cost effectiveness even during the downturns common in the oil industry.

An oil-field service company in Nigeria has operated an environmental system that combines existing statutory laws and community sensitivities to achieve proactive and sustainable approaches to environmental problems.

This paper discusses the environmental status of this service company's operations in Nigeria, environmental laws, community acuteness and practices around its operational bases, environmental management systems in place and compliance levels achieved, and the road map to sustained compliance. It also gives examples of data that are measured and maintained in a database. This service company has demonstrated that improved environmental performance can be achieved through an environmental management system that adopts an awareness of the community lifestyles, employee awareness training, and the measuring, recording and monitoring of environmental parameters and processes. Such a management system is profitable in time and money and protects multinational service companies against future exposures.
New Risk Assessment Approach Shows Significant Reduction in Oil Blowout Risk
Authors: Roald Tone H
Published: December 2007

Estimation of blow-out risk in the North Sea is based on blow-out data from the US Gulf of Mexico Outer Continental Shelf and the Norwegian and the UK sector of the North Sea area from the period 1980 until today. Very few blowout events with major release of oil have taken place in this period. Still environmental risk analysis of oil field development in the North Sea have predicted high probabilities of occurrence of blowouts with major oil releases.

Based on an updated and re-categorised blowout database new oil blowout estimates are made taking into account trends and relevance for North Sea conditions. Also blowout path distribution, blowout rate distribution and blowout duration distribution have been re-evaluated and used in the assessments. By using the updated and re-categorised blowout database, the estimated frequencies for major oil spills are at least an order of magnitude lower than obtained in earlier assessments.

The amount of oil spilled is a key factor regarding whether or not accidents may cause serious and long term environmental effects. Other factors, such as oil quality, location of the spill, weather and seasonal distribution of e.g. seabirds are other factors, which must be incorporated in an environmental risk assessment.

Based on statistics from the updated and re-categorised blow-out database, Norsk Hydro has assessed the probability for oil blowouts for some field developments in the North Sea and sorted the events in categories according to the released oil quantity. For each category, average discharge rate and discharge duration of the blowout are estimated for use in the environmental risk analysis. The calculations are performed so that it is possible to trace the events, which dominate the environmental risk in order to use these as a basis for emergency preparedness planning.

The method gives a more realistic picture of the environmental risk related to oil field development. It also points out the major risk contributors, making it possible to plan cost effective risk reduction measures when appropriate.
The Effect of Drilling Fluid Base Oil Properties on the Occupational Hygiene and the Marine Environment
Authors: Saasen A. , Berntsen M. , Løklingholm G. , Igeltjørn H. , Åsnes K.
Published: December 2007

Drilling operations can require the usage of oil base drilling fluids (OBM). These fluids are formulated as an emulsion consisting of water emulsified into a continuous oil phase. During the last decade the North Sea drilling industry has moved from using diesel oil to low toxic base oils in OBM. Further development of low toxic base oils has continued on the Norwegian Sector of the North Sea, and resulted in the use of non-aromatic base oils.

The current paper describes the results from a field test where the introduction of non-aromatic base oils reduced the hydrocarbon content by more than 50% in head space level in the shale shaker area compared to the use of low toxic base oils. In this test two wells were drilled where the hydrocarbon vapour and mist were collected at the same locations in the shaker area. The first well was drilled with a more traditional low toxic mineral oil based drilling fluid. The second well was drilled in a comparable formation with a drilling fluid based on the non-aromatic base oil. The paper also describes how skin irritation is reduced when using the non-aromatic base oils compared to the use of previous base oils and synthetic base oils. The reduction in skin irritation and hydrocarbon content at head space level has significantly improved the occupational hygiene for personnel exposed to drilling fluids offshore.

The paper also discusses biodegradability and toxicity of different base oils. Ecotoxicological test results indicate that use of the non-aromatic base oils may result in less environmental impact compared to use of other mineral oils or synthetic oils if an accidental discharge occurs.

Finally, the paper discusses dermal irritation effects from the different drilling fluids. It is shown that use of the non-aromatic base oil reduces the skin irritation index compared to use of other oil or synthetic base oils.
Bioremediation of a Crude Oil-polluted Clay Soil in a Temperate Zone
Authors: CHAINEAU C. H. , VIDALIE J. F. , GENESTE P. , DUCREUX J. , BALLERINI D.
Published: December 2007

Over the last five years, TOTALFINA, in partnership with COPAREX, TVD and IFP has been conducting research on the biodegradability of oily waste including oil-based mud drill cuttings and polluted soils. In the latter, hydrocarbons (HC) may enter the soil ecosystem as a result of accidental spillage. The bioremediation potential of HC polluted soils, by using cost-effective processes such as composting, was evaluated in a monitored and controlled pilot experiment. The combined fate and effects of HC on the ecosystem of highly oil contaminated soils were studied. Assessments of HC biodegradation rate, and the mobility and potential toxicity of soil and leachates or residual pollutants were performed. Clay polluted by 15 g of crude oil per kg of soil was treated in a static-ventilated biopile and in a series of six windrows periodically tilled. In these windrows different treatment parameters were applied such as addition of mineral nutrients or structuring agents (straw), or vegetal matter (grass). After 16 months, more than 85% of the initial HC were removed through biological processes in fertilised soils, whereas « natural attenuation » (i.e. with no specific treatment) was about 50%.

When adding fertilisers, residual pollution was mainly made up of a heavy fraction (more than 70 % with a mean carbon number higher than 40). Residual HC's were cyclic compounds including naphthenes, aromatics and resins which were strongly trapped on the organo-mineral matrix reducing by this way their bioavailability. The initial soil was toxic to earthworms and to plants. Soil toxicity decreased as soon as residual HC concentrations decreased. No toxic effects were shown by treated soils on earthworms nor inhibition on seed germination or in the Microtox assay after 16 months of bioremediation. Water-soluble HC and metabolites in leachates also drastically decreased as soon as HC biodegradation was proceeding.

This experimental work shows that bioremediation of an highly oil-polluted clay could be easily performed as soon as biological parameters influencing microbial growth were kept at the optimum. Composting of highly oil-polluted soils was shown to be an environmentally cost-effective alternative for the disposal of petroleum wastes. HC biodegradation was very efficient and minimal environmental impact was ensured by reducing toxicity of soils and leachates. After bioremediation, soils were successfully restored to vegetation.
Biodegradation of Water-Accommodated Fractions and Dispersed Oil in the Seawater Column
Authors: Brakstad O. G. , Faksness L. -G.
Published: December 2007

During the project "Advances Management of Oil Spills (AMOS)" biodegradation of oil compounds in the water-accomodated fractions and dispersed oils have been determined after discharge to the seawater. Water-accomodated fractions (WAFs) in seawater were generated by careful stirring in flasks according to a procedure established by the "Chemical Response to Oil Spills: Ecological Effect Research Forum (CROSERF)", with subsequent separation from the oil phase. Mechanically dispersed oils were generated and maintained by vigorous agitation. The initial oil-seawater loading ratios were 1:10,000. Primary biodegradation of selected oil components were measured as transformation by GC-FID and GC-MS analysis in both WAFs and dispersed oils during a period of 7 days (WAFs) or 14 days (dispersed oils), and transformation rates were calculated after corrections for abiotic disappearance. Acute toxicity of WAF was determined by the Microtox assay. Biodegradation was determined for various oils, for fresh and weathered oil, and for oil treated with a chemical dispersant. The transformation rates for similar components differed moderately between the various oils, and strongly depended on the distribution between WAF and dispersed oil phases. Introduction of a chemical dispersant in the oil had only small influence on the transformation. Comparison of fresh and weathered oils showed only small differences in degradation for compounds present in the oils (WAF). During degradation the acute toxicity was reduced for the oils. In conclusion, biodegradation of the oil WAFs will strongly influence the effects on pelagic organisms due to the rapid microbiological component transformation, while components present in oil droplets will persist for a longer period of time. This has significant implications for effect studies. The degradation data will be included in the spill simulation model "Oil-Spill Contingency and Response" (OSCAR 2000) for computation of behaviour and fates of oil spills.
A Mathematical Model Estimating Sea Water Discharge Time from a Hydrocarbon Storage Tank to Prevent Oil Spills
Authors: Mihcakan I. M. , Yamanlar S.
Published: December 2007

This study is conducted to prevent the accidental petroleum product release from some onshore storage tanks into seas, in Turkey. The seawater, used to displace the liquid petroleum products from tanker ships into the onshore storage tanks, accumulates under the petroleum product in the storage tank. The field personnel, operating the gravity-controlled seawater discharge manually, may occasionally miss the discharge time and close the discharge valve too late. Hence, the petroleum product, chasing seawater in the discharge line, is accidentally released to the sea. Thus, estimating the seawater discharge time accurately is of great value for eliminating the potential coastal and offshore environmental damage, preventing the petroleum product loss, and for efficient use of personnel time.

The flow behavior is modeled mathematically for the accurate estimation of total seawater discharge time. A semisteady-state flow model is developed by the integration of an unsteady-state mass balance and a steady-state energy balance. The effect of conical geometry of such tank bottoms on flow behavior is also taken into account. The differential equations of the model are solved by both analytical and numerical integration techniques. Excellent agreement of both results is obtained and compared with the field data.
Environmental Control
Authors: Shaaban Sh. I.
Published: December 2007

With the rise of the environmental protection movement, the petroleum industry has placed greater emphasis on minimizing the environmental impact of its operations. Moreover, this industry that conducts all exploration, production, treatment, storage and transportation activities, provides essential petroleum products that are used for transportation fuels, electrical power generation, space heating, medicine and petrochemicals.etc. The usage of petroleum products is a major contributor to our present standard of living. The activities of exploration and production of petroleum industry, however, can impact the environment, and the greatest impact arises from the release of wastes into the environment in concentrations that are not naturally found. While some of these wastes can have significant adverse effect on the environment, some have little impact. In virtually all cases, the adverse impact can be minimized or eliminated through the implementation of a proper waste management plan. Acutely conscious of the significance of its environmental responsibilities as an exploration and production company, Petrobel established a set of Basic Environmental Principles. Therefore it accepts responsibility for the environmental impact of its operations and is committed to safeguard the natural environment, people and the company, while striving to contrbute to the economic well-being of Egypt.
Geographic Information Systems and their Application to Environmental Data Management -- Case Study from Kazakhstan
Authors: Head Richard N. , Mason Mike W. , Ryder Alan A.
Published: December 2007

Environmental assessments collect vast amounts of data which is often useful for more than just its original purpose in the survey or EIA report. However, information in hard copy reports often becomes forgotten or its existence is unknown to others who may have a use for it. This situation is exasperated when more than one location may have use for the data or staff work back-to-back rotations. To avoid this loss of information, and to ensure additional costs are not generated collecting the same information again, a Geographical Information System (GIS) is being used as the tool to manage environmental data at Texaco's North Buzachi field in Kazakhstan.

Powerful geographic information systems, which run on desktop computers, can make a significant contribution to the management of environmental data. Texaco in North Buzachi have input all the data collected during its environmental studies onto a GIS. This will allow environmental staff in the field camp, in the offices in Aktau and London to access the data, manipulate it into future reports or permit applications and generally ensure that the data is recycled to maximise its value and minimise recollection costs. Additional information can easily be input onto the GIS so the database can grow as the field develops.

In this paper we show, by way of an illustrated case study, the types of data that can be collected, the problems that can be encountered and how they can be overcome and the range of uses that the data can be put to in the GIS. We discuss the costs and benefits of using GIS and importantly we discuss how GIS can add to the value of data by making it accessible to many users for a variety of applications - often long after the environmental data was collected.
Laboratory Studies of In Situ Coal Gasification
Authors: Steele Raymond D. , Nuttall H.E.
Published: December 2007

American Institute of Mining, Metallurgical, and Petroleum Engineers Inc.

An experimental program is underway to simulate the in situ gasification of coal. A laboratory combustion tube together with extensive auxiliary equipment have been designed and assembled. This apparatus has been successfully operated and data has been collected which simulates in situ gasification. This laboratory reactor, its operation and some preliminary data are reported. Problems in interpretation of the data are reported.

Introduction

With the advent of the recent energy crisis various methods for recovery of energy from coal have been suggested. Many of these suggestions have been schemes for gasifying coal to produce a low BTU gas (generally under 200 BTU/SCF). This gas could be used as a fuel, upgraded to pipeline quality gas or used as a chemical pipeline quality gas or used as a chemical feedstock. In general the coal used in these gasification schemes would be strip mined. The processes typically require considerable equipment and are as such quite expensive.

In the 19th century, a new process scheme was proposed and has recently attracted considerable attention. This scheme is that of in situ gasification. Conventional strip mining techniques are useful in extracting coal to a depth of approximately 200 feet below ground level. In situ recovery of coal offers the possibility of extracting coal to depths which possibility of extracting coal to depths which are not practical by more conventional techniques. As an example in New Mexico, coal is known to occur to depths in excess of 5000 feet below the surface. In fact, in excess of 95% of the coal in that state is not recoverable by present strip mining methods. The gasification of coal in place provides a potential means of reaching deposits not otherwise available for recovery due to their excessive depth and thin seams.

In addition to advantages obtained by reaching deposits not otherwise available, in situ techniques may very well be the most economic method for gasifying coal. It is possible that considerable advantage can be realized by the elimination of surface gasification equipment.
Fractional Flow Curves Derived by TDT Logs and Production Tests
Authors: Beaver M.H. , Lindley B.W. , McGhee B.F.
Published: December 2007

American Institute of Mining, Metallurgical, and Petroleum Engineers Inc.

In 1973, a (TDT*) logging program was initiated at Mobil Oil Corporation's West Ranch Field, Jackson County, Texas. This program had two objectives, to gain new data program had two objectives, to gain new data for an evaluation of the reserve status of each reservoir and to determine an optimum placement of perforations for a workover placement of perforations for a workover program. program. Thirty four wells have been evaluated from TDT data. Production tests of four major reservoirs in 22 of these wells were used with associated initial production tests to empirically derive Fractional Flow Curves for each reservoir. The plot for each reservoir is different. Yet each has the characteristic shape similar to a typical laboratory fractional flow curve.

When sufficient TDT and well test data are combined in a Fractional Flow Plot, the plot can be used to predict fractional flow plot can be used to predict fractional flow prior to perforating. Comparing this forecast prior to perforating. Comparing this forecast to actual production tests provides a guideline as to whether or not the test data reflects the true potential of the perforated interval.

Introduction

Preferential fluid flow in a permeability stratified reservoir can cause an operator to make poor decisions if he uses the "squeeze and shoot higher" practice prevalent in past years. The higher production rates demanded of today's operators intensify this problem. With higher production rates, water can move through higher permeability strata watering-out wells leaving undrained areas of a reservoir in less permeable stringers. On recompletion of a well in such an area, the operator tends to believe that his original reserve estimates were in error and can result in the loss of appreciable reserves, and cause unnecessary well work. This text describes a practical field technique which was used to aid the operator in dealing with this problem. problem. In 1973, Mobil Oil Corporation, initiated a re-evaluation of the West Ranch Field, Jackson County, Texas. This field was drilled in the late 1940's and early 1950's. The West Ranch Field is approximately six miles in length, four miles in width and covers some 10,400 productive acres. A "Type Log" is included for reference, Figure 1. Average data for each reservoir is listed in Table 1.
Tertiary Oil Recovery with Cellulose Derivatives as Water Thickeners
Authors: Falk David O. , Norton Charles
Published: December 2007

American Institute of Mining, Metallurgical, and Petroleum Engineers Inc.

A large number of cellulose derivatives were investigated for the effects of gram molecular weight, nature of substitution, and control of substitution on their respective performances as water thickeners in the mobility buffer in the Maraflood (trade mark) oil recovery process in laboratory 3" × 2' linear Berea cores. The best performances obtained with carboxymethylcellulose (CMC) derivatives of one million gram molecular weight, uniformly substituted to about 0.7–0.9 of a total 3.0 with sodium carboxymethyl groups on the glucose hydroxyl functions.

The best CMC tertiary oil recoveries compare quite favorably with results obtained with Dow 700 partially hydrolyzed polyacrylamide (PHPA) and Kelzan MF xanthan gum.

Introduction

This presentation summarizes our research on cellulose derivatives, especially carboxylcellulose (CMC). These commercial and research products were obtained from Herclules Corporation, products were obtained from Herclules Corporation, Dow Chemical Company, and Union Carbide. comparisons are also made with guar derivatives.

Chemical and physical properties, synergistic interactions, stability data, mobility control properties, and oil recoveries from prepared cores are presented. prepared cores are presented. Cellulose derivatives may be used to improve efficiency of waterflood displacement of oil in tertiary recoveries. Optimumly, substituted, high molecular weight carboxymethylated cellulose derivatives give good tertiary oil recoveries in Berea cores in the 250 to 1500 ppm concentration range. This approaches performances of Dow 700 Pusher polymer, a partially hydrolyzed Pusher polymer, a partially hydrolyzed polyacrylamide (PHPA), and Kelzan MF xanthan gum. polyacrylamide (PHPA), and Kelzan MF xanthan gum. Cellulose derivatives are comparable to xanthan gum in shear stability and salt sensitivity and superior to PHPA in these properties.

EXPERIMENTAL

REAGENTS.

Water-soluble cellulose derivatives of various types were investigated and are summarized in Table 1. Their solution characteristics depend upon the average chain length and the degree of substitution of functional groups.

Two types of cellulose ethers were tested:ionic sodium carboxymethylcellulose (CMC)hydroxyalkyl hydroxyethylcellulose (HEC).
Satellite Sea Ice Investigation of Beaufort Sea, Alaska
Authors: McLeod Wilfred , Hodder David T.
Published: December 2007

American Institute of Mining, Metallurgical, and Petroleum Engineers Inc.

Recent Nimbus 5 microwave (ESMR) satellite studies have cast serious doubt on the validity of USN Polar Atlas pack ice data. This paper reports on a study using LANDSAT-1 and -2 multispectral imagery and DAPP thermal infrared imagery to study, quantify and delineate Beaufort Sea ice conditions prevailing at intermediate stages of new ice formation and at break-up. From these data it will then be possible to evaluate the relative operational possible to evaluate the relative operational hazards associated with specific areas, and to study year to year regional variations.

Introduction

Virtually all Arctic operations are restricted by the severe climatic conditions that prevail. Yet paradoxically, these regions suffer from a universal scarcity of the environmental data required for planning and execution of logistics, exploration, and production. The recent spurt o exploration for Arctic offshore "frontier reserves" has resulted in an additional dimension, shortened time available to collect the required information by traditional oceanographic and meteorological methods. Furthermore, the cost of these traditional marine measurements, while always high, is compounded by time constraints and the severity of the climate. Although the region is usually ice-free in summer, it has a severe and complex icing problem. Annual ice buildup begins along shorelines and in shallow areas, but its movement thereafter is not fully understood. The need exists for a synoptic "time lapse study" of the ice formation and the possible paths for its movement as a function of variations in surface winds, ocean currents, wave action and the like. Indeed, the understanding of these latter environmental factors as potential operational hazards in their own light is a critical need.

Sea ice affects all logistical operations involved with exploration, platform siting, production and ultimately, product storage and transport. Of particular interest is estimation of ice thickness to aid in design of structures capable of resisting the implied ice forces.
Clay Stabilization Improves Sand Control
Authors: Tague J. R. , Lewallen S.
Published: December 2007

In a recent study, Chevron tested the capability of clay stabilizers to improve sand control in the Coalinga field. The need for improved sand control was driven by the high frequency of pump failures and associated increase in operating expense (OPEX). Before the clay stabilization treatments, most sand control efforts were focused on improving pump design and the continual replacement of old or worn-out slotted liners (re-drills). In a desire to improve overall returns and to reduce OPEX, a study was launched to determine the primary causes of sand entry and to improve overall sand control through clay stabilization.

The study initially gathered and analyzed data on the formation including sieve analysis, mineralogical analysis, and SEM microphotographs. Mineralogical analysis and SEM photographs obtained from core samples showed the grains to be weakly cemented by a combination of smectite and illite clays. Based on this data, a hypothesis was developed stating that wellbore sand entry was preceded by the release of the cementing clays, and thus by corollary, sand control could be improved by preventing the migration and release of the binding clays. To test this hypothesis, multiple wells were treated with a clay stabilizer designed to strengthen the chemical bond of the clays. To date, 22 wells have been treated for sand control, with 14 qualified successes. Based on these results, a standard treatment procedure has been designed, and candidate selection criteria developed. Overall, clay stabilization appears to be a quick and inexpensive method for improving sand control, especially when combined with more traditional methods.
Redevelopment Activities in the Carpinteria Field Offshore Santa Barbara County, California: Slimhole Horizontals Reap Big Benefits
Authors: Fleckenstein W. W. , Coombs S. F. , Edwards E. B.
Published: December 2007

Pacific Operators Offshore Inc. (POOI) as the operator of 3 leases within the Carpinteria field participated in two projects with the DOE that supported the planning and implementation of the Offshore Carpinteria Field redevelopment. The first was the Advanced Reservoir Management (ARM) Project, which used 3-D modeling and simulation to better identify target intervals for redevelopment. During the ARM project a 19 well workover program was initiated. The ARM project directly supported the second undertaking, a Class III field demonstration project. This included 6 redrills: 2 vertical pilots and 4 horizontal wells. Reservoir characterization efforts included extensive petrophysical and geologic work to thoroughly map and correlate the productive intervals and identify targets, which contained oil bypassed by the natural water drive. Drilling and completion accomplishments include the use of a modified workover rig (240,000 lb. mast) to drill the slimhole wells from 7" casing, and produce the non-gravel packed wells with rod driven production systems.

Only 19% of the estimated 521 million bbl original oil in place have been produced (98 million bbl) field wide. The analysis of the Carpinteria field and successful pilot 6 well drilling project has led to an extensive redevelopment plan. The initial results of the redevelopment program have been encouraging, with an additional production of 300,000 BOE. The tentative redevelopment plans include 18 to 27 horizontal wells, 5 to 9 vertical redrills, 20 to 30 workovers, a pilot waterflood, and possibly a full field waterflood project.
NMR Characterization of the Water Adsorbed by Montmorillonite: Impact on the Analysis of Porosity Logs
Authors: Chitale D. V. (Vivek) , Sigal Richard
Published: December 2007

Reservoir rocks contain interstitial pore water as well as the water adsorbed by the clay minerals. It was suggested by Chitale, et. al. (2000) based upon NMR characterization of montmorillonite that the threshold quantity of adsorbed water in this clay is 500 mg per g of dry clay, which agrees closely with the values reported in the clay science literature. This paper provides a summary of those aspects of hydration of montmorillonite that have direct bearing on log analysis and it highlights the impact of the optimization of amount of water adsorbed by montmorillonite on the interpretation of NMR-as well as conventional density and neutron porosity logs.

A new petrophysical parameter "wetness" is defined for montmorillonite as being the ratio of "volume of adsorbed water / volume of wet clay". A generic term "wetness-clay" applies to any clay. It computes to 0.57 for water-saturated montmorillonite. The wet clay density for montmorillonite available from the standard log interpretation charts (Halliburton, 1991 and Schlumberger, 1994) ranges between 2 to 2.7 g/cc. This paper refines the bulk wet clay density to 1.7g/cc for montmorillonite with a dry clay density range of 2.6-2.7 g/cc. It translates to an apparent wet clay density-porosity of 58%, which is a measure of the water adsorbed on montmorillonite surface. The refined value for thermal neutron porosity that measures both water and the hydroxyls in the clay is proposed to be 70%.

Rationalization of the wet clay-end-member values for the density, neutron logs based on the adsorbed water in montmorillonite should enhance the quality and accuracy of the overall log interpretation.
Fluid Identification and Pressure Transient Analysis in the Fractured Monterey Using the Modular Dynamics Tester
Authors: Grayson S. T. , Morris C. W. , Blume C. R.
Published: December 2007

The fractured Monterey formation of offshore California is estimated by the MMS to contain over one billion barrels of remaining reserves. Quantitative wireline evaluation in fractured reservoirs had been difficult in the past. Resistivity imaging using the FMI tool now provides the clarity to identify, orient, and quantify individual fractures. And recently, with the addition of the Modular Formation Dynamics Tester (MDT) tool, the fluid content of selected fractures can be positively identified while the tool is downhole. In addition, transient pressure analysis can be performed to reveal critical reservoir parameters. On a series of offshore Monterey wells, the FMI and MDT were used to identify and test fractures. The MDT was configured with the Dual Packer module in order to straddle-test fractured intervals selected from the FMI image. Tests were conducted to identify the fluid contained in the fractures, locate the reservoir gas cap, acquire pressure data, and take fluid samples. Perforations were confidently selected in the zones with the best quality fractures to maximize oil and to minimize gas production. Analysis of the buildup data provided formation pressure, permeability, and skin damage information. Comparisons of the fracture permeability with the corresponding resistivity image gave a visual calibration for enhanced image interpretation. Analysis of the formation pressures also provided an understanding of the hydraulic communication between different layers within the Monterey.
Overcoming Formation Damage in Heavy Oil Fields: A Comprehensive Approach
Authors: Tague James R.
Published: December 2007

Most heavy oil production occurs from shallow, unconsolidated sandstone reservoirs. Unfortunately, these reservoirs are prone to multiple forms of formation damage including sand and fines migration, clay swelling, organic precipitation, scale, and formation alteration caused by thermal EOR. In many cases, standard industry practices fail to remove or prevent this formation damage from occurring for a variety of reasons including improper identification of the damage mechanism and selection of inappropriate remedial or prevention techniques. This paper will present a comprehensive approach for optimizing production in heavy oil fields prone to formation damage. It will discuss the analytical methods used to identify and quantify multiple formation damage mechanisms, propose guidelines for remedial design, introduce some methods of statistical analysis used to determine optimal remedial treatments, and suggest some methods for implementing a field program for the remediation and prevention of formation damage. Overall, this paper should provide a useful methodology for improving production in any heavy oil field prone to multiple formation damage mechanisms.