COMPARATIVE ANALYSIS OF RESERVES DETERMINATION TECHNIQUES IN OVERPRESSURED GAS RESERVOIRS


COMPARATIVE ANALYSIS OF RESERVES DETERMINATION TECHNIQUES IN OVERPRESSURED GAS RESERVOIRS

Type: Project Materials | Format: Ms Word | Attribute: Documentation Only | Pages: 50 Pages | Chapters: 1-5 chapters | Price: ₦ 3,000.00

1,286 marked this research material reliable.
Call or whatsapp: +2347063298784 or email: info@allprojectmaterials.com
Excellent and professional research project topics and materials website. All the research tools, journals, seminars, essays, article, books, term papers, softwares and project materials for your research guide and final year projects are available here.

ABSTRACT

Conventional methods used in determining initial gas-in-place and reserves for a dry gas reservoir entails the use of P/z vs cumulative production data. In a normally pressured gas reservoir, the only important production mechanism is the compressibility of the gas. Many reservoir engineering calculations take advantage of this fact to simplify analysis. However, in deep geopressured gas reservoirs, the compressibility of the gas is much smaller and does not totally dominate production performance. Using simplified approaches may lead to serious errors in these cases. In geopressured systems, the compressibility of the rock and water may be just as large as the gas. Excluding these sources of energy from performance calculations would result in very pessimistic predictions of production versus pressure. Some investigators have postulated that water will be released from shales as the reservoir compacts during depletion. This would result in an internal water drive similar to aquifer influx. Because the reservoir rock is usually highly compressible and under-compacted, the decrease in pore volume during depletion may be very non-linear. Along with the rock compressibility, the absolute permeability may also decrease with declining pressure.

Several material balance models have been proposed to calculate the initial gas-in-place for abnormally-pressured gas reservoir. The present study is concerned with analyzing the different material balance models used to estimate IGIP for abnormally pressured reservoirs, review the bases and assumptions on which these models have been developed, as well as discuss the strength and weakness of every model. In addition, the study comprises comparative analysis of calculations of the IGIP by these material balance models for some reservoir case studies in the Gulf Coast. A sensitivity analysis is also done on some of the input parameters in these material balance models to determine their effect on estimating the original gas-in-place. Moreover, the present investigation reveals that most of the material balance models analyzed in this study are sensitive to the value of the initial reservoir pressure and the early data. Unfortunately, this is the time when reliable estimate for the IGIP is vital for economic decision regarding the development of such gas reservoirs. However, accurate estimation of the IGIP plays an important role in the evaluation, analysis, prediction of future performance, and making economic decision regarding the development of gas reservoirs.



CHAPTER 1 - Introduction

Gas reservoirs with abnormally-high pressures have been encountered all over the world. For these reservoirs, a straight line plot of P/z versus Gp for the early production data and extrapolation to zero reservoir pressure projects incorrect initial gas-in-place (IGIP). The P/z plot is based on the assumption that gas compressibility is the “sole” reservoir driving mechanism. In overpressured gas reservoirs however, grain expansion, formation water expansion and water influx from shale or small associated aquifer, in addition to gas expansion contribute significantly to gas production. In normally pressured reservoirs, the pore volume change with pressure is considered minimal, and thus the pore volume (formation) compressibility retains a very small constant value. However, in an overpressured gas reservoir, the natural compaction is incomplete, as a large portion of the overburden remains supported by high internal pore pressure. As this pressure is released, through fluid production, the pore space may reduce significantly. Thus, under overpressured conditions, cf is relatively large and may have significant variation with pressure. This becomes important to the material-balance equation, as the pore compressibility is a significant energy term in overpressured reservoirs. In normally pressured gas reservoirs, the energy of the formation is usually negligible compared to the energy of the gas.

Overpressures are subsurface fluid pressures that are greater than the pressures expected under normal hydrostatic conditions. Overpressured reservoirs are abundant in sedimentary basins throughout the world. In the United States, abnormally-pressured gas reservoirs are concentrated in the Gulf Coast, Anardako Basin, Delaware Basin and Rocky Mountain Area. In the Middle East, overpressured gas reservoirs are found in Iraq, Iran and Saudi Arabia. These reservoirs commonly produce light oils and gases and require special evaluation techniques. Prior knowledge of the possibility of encountering overpressures at particular subsurface depths is important when exploring for oil and gas. This is because the presence of higher-than-normal pressure increases the complexity and cost of drilling, well-completions and production operations. Additionally, the effect of overpressures on reservoir behavior must be recognized when predicting performance.

Initial reservoir pressure gradients are normally 0.465 psi/ft of depth, which is the hydrostatic gradient of typical brine. In many producing areas, particularly along the Gulf Coast, reservoirs exist with pressure gradients far in excess of this normal. Gradients of almost 1.0 psi/ft of depth have been observed. Any gradient in excess of 0.465 is abnormal, but the effects of abnormal pressure on reservoir engineering calculations are often ignored unless a gradient of 0.65 psi/ft or more exists. A significant amount of gas exists in abnormally-pressured reservoirs. In the offshore Gulf Coast alone, over 300 gas reservoirs have been discovered with initial gradients in excess of 0.65 psi/ft at depths greater than 10,000 ft [Bernard (1985)].

COMPARATIVE ANALYSIS OF RESERVES DETERMINATION TECHNIQUES IN OVERPRESSURED GAS RESERVOIRS

Additional Information

  • The Project Material is available for download.
  • The Research material is delivered within 15-30 Minutes.
  • The Material is complete from Preliminary Pages to References.
  • Well Researched and Approved for supervision.
  • Click the download button below to get the complete project material.

Frequently Asked Questions

In-order to give you the best service available online, we have compiled frequently asked questions (FAQ) from our clients so as to answer them and make your visit much more interesting.

We are proudly Nigerians, and we are well aware of fraudulent activities that has been ongoing in the internet. To make it well known to our customers, we are geniune and duely registered with the Corporate Affairs Commission of the republic of Nigeria. Remember, Fraudulent sites can NEVER post bank accounts or contact address which contains personal information. Free chapter One is always given on the site to prove to you that we have the material. If you are unable to view the free chapter 1 send an email to info@allprojectmaterials.com with the subject head "FREE CHAPTER 1' plus the topic. You will get a free chapter 1 within an hour. You can also check out what our happy clients have to say.


Students are always advised to use our materials as guide. However, if you have a different case study, you may need to consult one of our professional writers to help you with that. Depending on similarity of the organization/industry you may modify if you wish.


We have professional writers in various disciplines. If you have a fresh topic, just click Hire a Writer or click here to fill the form and one of our writers will contact you shortly.


Yes it is a complete research project. We ensure that our client receives complete project materials which includes chapters 1-5, full references, questionnaires/secondary data, etc.


Depending on how fast your request is acknowledged by us, you will get the complete project material withing 15-30 minutes. However, on a very good day you can still get it within 5 minutes!

What Clients Say

Our Researchers are happy, see what they are saying. Share your own experience with the world.
Be polite and honest, as we seek to expand our business and reach more people. Thank you.

Project Information

  • CATEGORY : PETROLEUM ENGINEERING
  • TYPE : PROJECT MATERIAL
  • FORMAT : MICROSOFT WORD
  • ATTRIBUTE : Documentation Only
  • PAGES : 50 Pages
  • CHAPTERS : 1 - 5
  • PRICE : ₦ 3,000.00

Share Links

Download Post
Download Post

Search for Project Topics

Project topics in Departments

Do you need a writer for your academic work?

Reviews:
A Review on comparative analysis of reserves determination techniques in overpressured gas reservoirs, comparative, analysis, reserves project topics, researchcub.info, project topic, list of project topics, research project topics, journals, books, Academic writer.
Overpressures are subsurface fluid pressures that are greater than the pressures expected under normal hydrostatic conditions. Overpressured reservoirs are abundant in sedimentary basins throughout the world. In the United States, abnormally-pressured gas reservoirs are concentrated in the Gulf Coast, Anardako Basin, Delaware Basin and Rocky Mountain Area. In the Middle East, overpressured gas reservoirs are found in Iraq, Iran and Saudi Arabia. These reservoirs commonly produce light oils and gases and require special evaluation techniques. Prior knowledge of the possibility of encountering overpressures at particular subsurface depths is important when exploring for oil and gas. This is because the presence of higher-than-normal pressure increases the complexity and cost of drilling, well-completions and production operations. Additionally, the effect of overpressures on reservoir behavior must be recognized when predicting performance... petroleum engineering project topics

COMPARATIVE ANALYSIS OF RESERVES DETERMINATION TECHNIQUES IN OVERPRESSURED GAS RESERVOIRS