IMPROVING RECOVERY IN A THIN OIL COLUMN RESERVOIR—TUNA M–1 RESERVOIR EXPERIENCE IN THE GIPPSLAND BASIN, SOUTHEAST AUSTRALIA

2003 ◽  
Vol 43 (1) ◽  
pp. 175
Author(s):  
C. Santamaria ◽  
R. Fish
Keyword(s):  
Horizontal Well ◽  
Pressure Support ◽  
Horizontal Wells ◽  
Surveillance Data ◽  
Reservoir Properties ◽  
Actual Performance ◽  
New West ◽  
Expected Performance ◽  
Oil Rim ◽  
Gippsland Basin

The Tuna M–1 reservoir was developed in 1997 from both the new West Tuna platform and the existing Tuna A platform in the Gippsland Basin. The M–1 reservoir is contained within an anticlinal closure with an approximate gross hydrocarbon column of 85 metres. The oil column was originally 12 m thick and is supported by a large gas cap and a strong flank aquifer.Performance from the M–1 reservoir has been good, due to excellent reservoir properties. The combination of conventional and geo-steered horizontal wells has performed well with recovery efficiencies of 70% observed in many parts of the field. Lower than expected performance from the northwestern edge of the oil rim was, however, a significant anomaly, with recovery efficiencies 10% lower than from comparable rock in the southern and eastern parts of the field. The underlying cause of this lower performance was believed to be the result of an anisotropic aquifer response allowing greater pressure support along the northwestern flank of the fieldA re-entry well was drilled from a watered out horizontal well on the Tuna A platform in December 2000. This well was drilled as an oil production opportunity and as a key surveillance data point for the northwestern flank of the field. Results led to further surveillance including contact monitoring and production logging in horizontal wells. In addition to this, simulations were updated to reflect actual performance and surveillance data. Subsequent analysis supported development of a work program for new M–1 drainage points, including additional drill wells and the conversion of existing, watered out horizontal wells to conventional wells. The M–1 redevelopment work has been highly successful with production rates increasing by about 20,000 barrels per day in the first nine months of the program.

scholarly journals Evaluation of Reservoir Quality and Forecasted Production Variability along a Multi-Fractured Horizontal Well. Part 1: Reservoir Characterization

Energies ◽  
2021 ◽  
Vol 14 (19) ◽  
pp. 6154
Author(s):  
Daniela Becerra ◽  
Christopher R. Clarkson ◽  
Amin Ghanizadeh ◽  
Rafael Pires de Lima ◽  
Farshad Tabasinejad ◽  
...  
Keyword(s):  
Horizontal Well ◽  
Reservoir Characterization ◽  
Water Saturation ◽  
Geometric Approach ◽  
Horizontal Wells ◽  
Reservoir Quality ◽  
Reservoir Properties ◽  
Geomechanical Properties ◽  
Using Data ◽  
Lateral Length

Completion design for horizontal wells is typically performed using a geometric approach where the fracturing stages are evenly distributed along the lateral length of the well. However, this approach ignores the intrinsic vertical and horizontal heterogeneity of unconventional reservoirs, resulting in uneven production from hydraulic fracturing stages. An alternative approach is to selectively complete intervals with similar and superior reservoir quality (RQ) and completion quality (CQ), potentially leading to improved development efficiency. In the current study, along-well reservoir characterization is performed using data from a horizontal well completed in the Montney Formation in western Canada. Log-derived petrophysical and geomechanical properties, and laboratory analyses performed on drill cuttings, are integrated for the purpose of evaluating RQ and CQ variability along the well. For RQ, cutoffs were applied to the porosity (>4%), permeability (>0.0018 mD), and water saturation (<20%), whereas, for CQ, cutoffs were applied to rock strength (<160 Mpa), Young’s Modulus (60–65 GPa), and Poisson’s ratio (<0.26). Based on the observed heterogeneity in reservoir properties, the lateral length of the well can be subdivided into nine segments. Superior RQ and CQ intervals were found to be associated with predominantly (massive) porous siltstone facies; these intervals are regarded as the primary targets for stimulation. In contrast, relatively inferior RQ and CQ intervals were found to be associated with either dolomite-cemented facies or laminated siltstones. The methods developed and used in this study could be beneficial to Montney operators who aim to better predict and target sweet spots along horizontal wells; the approach could also be used in other unconventional plays.

scholarly journals Optimizing productivity in oil rims: simulation studies on horizontal well placement under simultaneous oil and gas production

2020 ◽  
Author(s):  
Oluwasanmi Olabode ◽  
Sunday Isehunwa ◽  
Oyinkepreye Orodu ◽  
Daniel Ake
Keyword(s):  
Oil Recovery ◽  
Oil And Gas ◽  
Horizontal Wells ◽  
Gas Production ◽  
Gas Oil ◽  
Reservoir Properties ◽  
Well Placement ◽  
Hydrocarbon Production ◽  
Oil And Gas Production ◽  
Oil Rim

AbstractThin oil rim reservoirs are predominantly those with pay thickness of less than 100 ft. Oil production challenges arise due to the nature of the gas cap and aquifer in such reservoirs and well placement with respect to the fluid contacts. Case studies of oil rim reservoir and operational properties from the Niger-Delta region are used to build classic synthetic oil rim models with different reservoir parameters using a design of experiment. The black oil simulation model of the ECLIPSE software is activated with additional reservoir properties and subsequently initialized to estimate initial oil and gas in place. To optimize hydrocarbon production, 2 horizontal wells are initiated, each to concurrently produce oil and gas. Well placements of (0.5 ft., 0.25 ft. and 0.75 ft.) are made with respect to the pay thickness and then to the fluid contacts. The results show that for oil rim with bigger aquifers, an oil recovery of 8.3% is expected when horizontal wells are placed at 0.75 ft. of the pay thickness away from the gas oil contact, 8.1% oil recovery in oil rims with larger gas caps with completions at 0.75 ft. of the pay zone from the gas oil contacts, 6% oil recovery with relatively small gas caps and aquifer and 9.3% from oil rims with large gas caps and aquifers, with completions at mid-stream of the pay zone.

Multidisciplinary approach in determining the best zone to land a Haynesville horizontal well

2014 ◽  
Vol 2 (4) ◽  
pp. T243-T254
Author(s):  
Shujie Liu ◽  
Adrian Zett ◽  
David Spain ◽  
Michael Rabinovich ◽  
Travis Gillham ◽  
...  
Keyword(s):  
Horizontal Well ◽  
Multidisciplinary Approach ◽  
Clay Content ◽  
Horizontal Wells ◽  
Upper Jurassic ◽  
Reservoir Properties ◽  
East Texas Basin ◽  
Microseismic Data ◽  
Open Hole ◽  
Rabbit Ears

The Upper Jurassic Haynesville Shale Formation in the East Texas Basin, North America, is a black, organic-rich, calcareous mudstone that lies below the Bossier Shale and above the Cotton Valley Limestone. The reservoir quality was controlled by primary depositional process and secondary diagenesis. The best lithology type in terms of drilling, completion, and production is the organic-rich, silty calcareous mudstone with low clay content. The studied well traversed the entire Haynesville Formation with the objective to assess the production potential of this formation. We acquired open-hole, triple-combo logging while drilling (LWD) logs, two types of production logs, and regional microseismic data. Postdrill log modeling confirmed that the horizontal well stayed on the planned trajectory, based on the log correlation between the horizontal and offset wells. Log modeling demonstrated that the LWD resistivity logs in horizontal wells are subject to resistivity anisotropy and polarization horn effects. We integrated the production log results with the open-hole, log formation evaluation and mineralogy-based brittleness index, to understand the static reservoir properties and dynamic inflow performance. The open-hole and cased-hole logs consistently showed that the “rabbit ears” interval at the base of the Upper Haynesville and the top interval of the Upper Haynesville were excellent lateral well-landing zones for best production. We combined microseismic data with production log data and found that the effective stimulated rock volume by hydraulic fracturing was mostly concentrated in the top interval of the Upper Haynesville and the “rabbit ears” interval at the base of the Upper Haynesville. The study demonstrated that a multidisciplinary approach was necessary in determining the best zone to land Haynesville horizontal wells.

The Interpretation Technique of Rate Transient Analysis Data in Fractured Horizontal Wells

2021 ◽  
Author(s):  
Ruslan Rubikovich Urazov ◽  
Alfred Yadgarovich Davletbaev ◽  
Alexey Igorevich Sinitskiy ◽  
Ilnur Anifovich Zarafutdinov ◽  
Artur Khamitovich Nuriev ◽  
...  
Keyword(s):  
Hydraulic Fracturing ◽  
Transient Analysis ◽  
Horizontal Well ◽  
Horizontal Wells ◽  
Data Interpretation ◽  
Analysis Data ◽  
Well Logging ◽  
Rate Transient Analysis ◽  
Fractured Horizontal Well ◽  
Fractured Horizontal Wells

Abstract This research presents a modified approach to the data interpretation of Rate Transient Analysis (RTA) in hydraulically fractured horizontal well. The results of testing of data interpretation technique taking account of the flow allocation in the borehole according to the well logging and to the injection tests outcomes while carrying out hydraulic fracturing are given. In the course of the interpretation of the field data the parameters of each fracture of hydraulic fracturing were selected with control for results of well logging (WL) by defining the fluid influx in the borehole.

Improving Proppant Placement Success in Horizontal Wells in Layered Reservoirs in the Sultanate of Oman

2021 ◽  
Author(s):  
Andrew Boucher ◽  
Josef Shaoul ◽  
Inna Tkachuk ◽  
Mohammed Rashdi ◽  
Khalfan Bahri ◽  
...  
Keyword(s):  
Horizontal Well ◽  
Complex Geometry ◽  
Horizontal Wells ◽  
Vertical Position ◽  
Sultanate Of Oman ◽  
Vertical Wells ◽  
Multiple Fractures ◽  
Initiation Point ◽  
Interval Selection ◽  
Geological Units

Abstract A gas condensate field in the Sultanate of Oman has been developed since 1999 with vertical wells, with multiple fractures targeting different geological units. There were always issues with premature screenouts, especially when 16/30 or 12/20 proppant were used. The problems placing proppant were mainly in the upper two units, which have the lowest permeability and the most heterogeneous lithology, with alternating sand and shaly layers between the thick competent heterolith layers. Since 2015, a horizontal well pilot has been under way to determine if horizontal wells could be used for infill drilling, focusing on the least depleted units at the top of the reservoir. The horizontal wells have been plagued with problems of high fracturing pressures, low injectivity and premature screenouts. This paper describes a comprehensive analysis performed to understand the reasons for these difficulties and to determine how to improve the perforation interval selection criteria and treatment approach to minimize these problems in future horizontal wells. The method for improving the success rate of propped fracturing was based on analyzing all treatments performed in the first seven horizontal wells, and categorizing their proppant placement behavior into one of three categories (easy, difficult, impossible) based on injectivity, net pressure trend, proppant pumped and screenout occurrence. The stages in all three categories were then compared with relevant parameters, until a relationship was found that could explain both the successful and unsuccessful treatments. Treatments from offset vertical wells performed in the same geological units were re-analyzed, and used to better understand the behavior seen in the horizontal wells. The first observation was that proppant placement challenges and associated fracturing behavior were also seen in vertical wells in the two uppermost units, although to a much lesser extent. A strong correlation was found in the horizontal well fractures between the problems and the location of the perforated interval vertically within this heterogeneous reservoir. In order to place proppant successfully, it was necessary to initiate the fracture in a clean sand layer with sufficient vertical distance (TVT) to the heterolith (barrier) layers above and below the initiation point. The thickness of the heterolith layers was also important. Without sufficient "room" to grow vertically from where it initiates, the fracture appears to generate complex geometry, including horizontal fracture components that result in high fracturing pressures, large tortuosity friction, limited height growth and even poroelastic stress increase. This study has resulted in a better understanding of mechanisms that can make hydraulic fracturing more difficult in a horizontal well than a vertical well in a laminated heterogeneous low permeability reservoir. The guidelines given on how to select perforated intervals based on vertical position in the reservoir, rather than their position along the horizontal well, is a different approach than what is commonly used for horizontal well perforation interval selection.

scholarly journals THE ANALYSIS OF METHODS OF RESERVOIR POROSITY-PERMEABILITY PROPERTIES STUDY IN HORIZONTAL WELLS TO ESTIMATE THE BOTTOM-HOLE TREATMENT RESULTS

2016 ◽  
pp. 72-77
Author(s):  
I. I. Mannanov ◽  
L. I. Garipova
Keyword(s):  
Horizontal Wells ◽  
Practical Application ◽  
Treatment Results ◽  
Reservoir Properties ◽  
Bottom Hole ◽  
Reservoir Porosity ◽  
Analysis Of Dynamics

Obtaining of the information about reservoir properties of formations is the basis of designing and the results analysis of production stimulation methods. Now two directions have been widely studied and applied, i.e. the hydrodynamic studies implementation using the method of the level recovery and the prolong analysis of dynamics of well producing characteristics. The paper discusses the practical application of both approaches for estimation of the need in treatment and the results of production intensification methods.

scholarly journals A practical method for planning large number of horizontal wells with a reservoir model for a field development plan

2021 ◽  
Vol 10 ◽  
pp. 17-32
Author(s):  
Guido Fava ◽  
Việt Anh Đinh
Keyword(s):  
Horizontal Well ◽  
Horizontal Wells ◽  
Simulation Software ◽  
Production Performance ◽  
Development Plan ◽  
Regular Pattern ◽  
Production Forecast ◽  
Advanced Technique ◽  
Large Reservoir ◽  
Field Development

The most advanced technique to evaluate different solutions proposed for a field development plan consists of building a numerical model to simulate the production performance of each alternative. Fields covering hundreds of square kilometres frequently require a large number of wells. There are studies and software concerning optimal planning of vertical wells for the development of a field. However, only few studies cover planning of a large number of horizontal wells seeking full population on a regular pattern. One of the criteria for horizontal well planning is selecting the well positions that have the best reservoir properties and certain standoffs from oil/water contact. The wells are then ranked according to their performances. Other criteria include the geometry and spacing of the wells. Placing hundreds of well individually according to these criteria is highly time consuming and can become impossible under time restraints. A method for planning a large number of horizontal wells in a regular pattern in a simulation model significantly reduces the time required for a reservoir production forecast using simulation software. The proposed method is implemented by a computer script and takes into account not only the aforementioned criteria, but also new well requirements concerning existing wells, development area boundaries, and reservoir geological structure features. Some of the conclusions drawn from a study on this method are (1) the new method saves a significant amount of working hours and avoids human errors, especially when many development scenarios need to be considered; (2) a large reservoir with hundreds of wells may have infinite possible solutions, and this approach has the aim of giving the most significant one; and (3) a horizontal well planning module would be a useful tool for commercial simulation software to ease engineers' tasks.

scholarly journals Development of an analytical model to predict oil reservoirs performance using mechanical waves propagation

2021 ◽  
Author(s):  
Hesham A. Abu Zaid ◽  
◽  
Sherif A. Akl ◽  
Mahmoud Abu El Ela ◽  
Ahmed El-Banbi ◽  
...  
Keyword(s):  
Oil Recovery ◽  
Field Measurements ◽  
Field Trials ◽  
Oil Field ◽  
Reservoir Properties ◽  
Actual Performance ◽  
Reservoir Performance ◽  
Mechanical Waves ◽  
Incremental Oil Recovery ◽  
Wave Induced

The mechanical waves have been used as an unconventional enhanced oil recovery technique. It has been tested in many laboratory experiments as well as several field trials. This paper presents a robust forecasting model that can be used as an effective tool to predict the reservoir performance while applying seismic EOR technique. This model is developed by extending the wave induced fluid flow theory to account for the change in the reservoir characteristics as a result of wave application. A MATLAB program was developed based on the modified theory. The wave’s intensity, pressure, and energy dissipation spatial distributions are calculated. The portion of energy converted into thermal energy in the reservoir is assessed. The changes in reservoir properties due to temperature and pressure changes are considered. The incremental oil recovery and reduction in water production as a result of wave application are then calculated. The developed model was validated against actual performance of Liaohe oil field. The model results show that the wave application increases oil production from 33 to 47 ton/day and decreases water-oil ratio from 68 to 48%, which is close to the field measurements. A parametric analysis is performed to identify the important parameters that affect reservoir performance under seismic EOR. In addition, the study determines the optimum ranges of reservoir properties where this technique is most beneficial.

scholarly journals Mathematical description of a bounded oil reservoir with a horizontal well

2021 ◽  
Vol 2 (1) ◽  
pp. 67-76
Author(s):  
T. N. Nzomo ◽  
S. E Adewole ◽  
K. O Awuor ◽  
D. O. Oyoo
Keyword(s):  
Pressure Distribution ◽  
Effective Permeability ◽  
Horizontal Well ◽  
Horizontal Wells ◽  
Oil Reservoir ◽  
Vertical Wells ◽  
Anisotropic Permeability ◽  
Time Approximation ◽  
Reservoir Geometry ◽  
Short Time

Horizontal wells are more productive compared to vertical wells if their performance is optimized. For a completely bounded oil reservoir, immediately the well is put into production, the boundaries of the oil reservoir have no effect on the flow. The pressure distribution thus can be approximated with this into consideration. When the flow reaches either the vertical or the horizontal boundaries of the reservoir, the effect of the boundaries can be factored into the pressure distribution approximation. In this paper we consider the above cases and present a detailed mathematical model that can be used for short time approximation of the pressure distribution for a horizontal well with sealed boundaries. The models are developed using appropriate Green’s and source functions. In all the models developed the effect of the oil reservoir boundaries as well as the oil reservoir parameters determine the flow period experienced. In particular, the effective permeability relative to horizontal anisotropic permeability, the width and length of the reservoir influence the pressure response. The models developed can be used to approximate and analyze the pressure distribution for horizontal wells during a short time of production. The models presented show that the dimensionless pressure distribution is affected by the oil reservoir geometry and the respective directional permeabilities.

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