• Login
    View Item 
    •   Home
    • Theses & Dissertations
    • 2015 - Mines Theses & Dissertations
    • View Item
    •   Home
    • Theses & Dissertations
    • 2015 - Mines Theses & Dissertations
    • View Item
    JavaScript is disabled for your browser. Some features of this site may not work without it.

    Browse

    All of Mines RepositoryCommunitiesPublication DateAuthorsTitlesSubjectsThis CollectionPublication DateAuthorsTitlesSubjects

    My Account

    Login

    Mines Links

    Arthur Lakes LibraryColorado School of Mines

    Statistics

    Display Statistics

    Analytical investigation of boundaries in naturally fractured unconventional reservoirs, An

    • CSV
    • RefMan
    • EndNote
    • BibTex
    • RefWorks
    Thumbnail
    Name:
    Greenwood_mines_0052N_10664.pdf
    Size:
    3.075Mb
    Format:
    PDF
    Description:
    Thesis
    Download
    Thumbnail
    Name:
    Greenwood_mines_0052N_316.zip
    Size:
    13.17Kb
    Format:
    Unknown
    Description:
    Data
    Download
    Author
    Greenwood, Judson T.
    Advisor
    Ozkan, E.
    Date issued
    2015
    Keywords
    shale
    boundaries
    analytical modeling
    reservoir engineering
    fractured
    unconventional
    Shale gas
    Horizontal gas well drilling
    Porosity
    Mathematical models
    Natural gas
    
    Metadata
    Show full item record
    URI
    https://hdl.handle.net/11124/17084
    Abstract
    This research presents a heuristic approach to develop an analytical model to study the effects of a stimulated zone in a fractured unconventional reservoir and the inherent boundaries that are observed. To simulate a stimulated reservoir volume (SRV) around the fractured horizontal well surrounded by a virgin outer reservoir, three separate solutions are generated and superimposed: Solution 1 - a multiply fractured, horizontal-well in an infinite-acting, homogeneous reservoir with the properties of the outer zone; Solution 2 - a multiply fractured, horizontal-well in a bounded, homogeneous (un-fractured) reservoir with the properties of the outer reservoir; and Solution 3 - a multiply fractured, horizontal-well in a bounded, naturally fractured reservoir with the properties of the stimulated zone. The solution for the composite reservoir consisting of a stimulated (naturally fractured) reservoir surrounded by an infinite acting, un-fractured (virgin) reservoir is obtained by subtracting Solution 2 from Solution 1 and then adding Solution 3. The same approach is also applied to develop a solution for the case where there is an additional transition zone between the SRV and the outer (virgin) reservoir. This method creates an approximate solution for the composite-reservoir system. Although the model is derived analytically, computations require numerical methods and the model is therefore referred to as semi-analytical. The model is verified against literature models and an industry numerical simulator to find its limitations. This verification shows that the accuracy of the model is dependent on the size of the stimulated zone. For a large stimulated zone, because the flux profiles along the boundaries of the fractured (Solution 3) and un-fractured (Solution 2) reservoirs are not equal, the model over-predicts the drawdown pressure. However in real-world examples of multiply fractured horizontal wells, the stimulated zone is much smaller and the model closely matches the drawdown pressures calculated in the numerical simulator. Therefore, the heuristic approach used in this work leads to an ad-hoc solution for the common configurations of fractured horizontal wells in shale reservoirs. Several synthetic examples are considered to show that the solution developed in this work can be used to identify the flow regimes after the effect of the stimulated reservoir boundary (that is, the fracture tip effects) are felt. This is an advantage over the commonly used trilinear model when the diffusivities of the stimulated and virgin reservoirs are comparable. Although not explored in this research, the ultimate utility of the proposed approach is in modeling multiple fractured-horizontal-wells to study the interference among SRVs. The fracture enhancement and extent influence the productivity of the well more than any other parameter and should be of utmost importance to characterize. And last, this model can be used with other tools to identify optimal full field development.
    Rights
    Copyright of the original work is retained by the author.
    Collections
    2015 - Mines Theses & Dissertations

    entitlement

     
    DSpace software (copyright © 2002 - 2023)  DuraSpace
    Quick Guide | Contact Us
    Open Repository is a service operated by 
    Atmire NV
     

    Export search results

    The export option will allow you to export the current search results of the entered query to a file. Different formats are available for download. To export the items, click on the button corresponding with the preferred download format.

    By default, clicking on the export buttons will result in a download of the allowed maximum amount of items.

    To select a subset of the search results, click "Selective Export" button and make a selection of the items you want to export. The amount of items that can be exported at once is similarly restricted as the full export.

    After making a selection, click one of the export format buttons. The amount of items that will be exported is indicated in the bubble next to export format.