skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Hydraulic Fractures in Core From Stimulated Reservoirs: Core Fracture Description of HFTS Slant Core, Midland Basin, West Texas

Abstract

The geometry and extent of the hydraulic-fracture network produced during well stimulation are generally not well known. Indirect methods such as microseismic monitoring may provide information about the network, but they are not definitive. The Hydraulic Fracture Test Site (HFTS) project was designed to recover core from a stimulated volume, thus providing direct information about hydraulic fractures. Here we present methods and some results from a fracture description of the HFTS slant well cores. Methods: The 4-inch-diameter cores were contained within an aluminum tube and were examined prior to slabbing. We developed criteria for distinguishing between hydraulic, natural, drilling-induced, and core-handling fractures by examining the orientation and surface features of all fractures, making use of a CT scan of the core. Results: More than 700 fractures total were found in 600 ft of core, including hydraulic fractures, two sets of calcite-sealed natural fractures, and drilling-induced and core-handling fractures. Hydraulic fractures were found to be most abundant in the section of core closest to the stimulated wells. Significance: Benefits from an experiment of this type are: (1) Hydraulic fractures are observed directly, allowing fracture density and spatial distribution to be quantified. (2) Twist hackles on hydraulic-fracture surfaces may provide information aboutmore » the direction of fracture propagation. (3) The degree to which natural, sealed fractures have been reactivated may be assessed. (4) Proppant distribution in the fractures can be examined. (5) Details of the observed hydraulic-fracture network can be used to verify, or provide input data for, models of hydraulic-fracture growth and proppant distribution. (6) Findings can provide ground truth for indirect diagnostic techniques such as microseismic monitoring. (7) Fractures in core and image log in the same well can be compared, and findings used to help calibrate other horizontal well image logs.« less

Authors:
; ;
Publication Date:
Research Org.:
GTI
Sponsoring Org.:
USDOE Office of Fossil Energy (FE)
OSTI Identifier:
1475414
Report Number(s):
URTeC: 2902624
DOE Contract Number:  
FE0024292
Resource Type:
Conference
Resource Relation:
Conference: Unconventional Resources Technology Conference, Houston, Texas, USA, 23-25 July 2018
Country of Publication:
United States
Language:
English

Citation Formats

Gale, Julia, Elliott, Sara, and Laubach, Stephen. Hydraulic Fractures in Core From Stimulated Reservoirs: Core Fracture Description of HFTS Slant Core, Midland Basin, West Texas. United States: N. p., 2018. Web. doi:10.15530/urtec-2018-2902624.
Gale, Julia, Elliott, Sara, & Laubach, Stephen. Hydraulic Fractures in Core From Stimulated Reservoirs: Core Fracture Description of HFTS Slant Core, Midland Basin, West Texas. United States. doi:10.15530/urtec-2018-2902624.
Gale, Julia, Elliott, Sara, and Laubach, Stephen. Tue . "Hydraulic Fractures in Core From Stimulated Reservoirs: Core Fracture Description of HFTS Slant Core, Midland Basin, West Texas". United States. doi:10.15530/urtec-2018-2902624. https://www.osti.gov/servlets/purl/1475414.
@article{osti_1475414,
title = {Hydraulic Fractures in Core From Stimulated Reservoirs: Core Fracture Description of HFTS Slant Core, Midland Basin, West Texas},
author = {Gale, Julia and Elliott, Sara and Laubach, Stephen},
abstractNote = {The geometry and extent of the hydraulic-fracture network produced during well stimulation are generally not well known. Indirect methods such as microseismic monitoring may provide information about the network, but they are not definitive. The Hydraulic Fracture Test Site (HFTS) project was designed to recover core from a stimulated volume, thus providing direct information about hydraulic fractures. Here we present methods and some results from a fracture description of the HFTS slant well cores. Methods: The 4-inch-diameter cores were contained within an aluminum tube and were examined prior to slabbing. We developed criteria for distinguishing between hydraulic, natural, drilling-induced, and core-handling fractures by examining the orientation and surface features of all fractures, making use of a CT scan of the core. Results: More than 700 fractures total were found in 600 ft of core, including hydraulic fractures, two sets of calcite-sealed natural fractures, and drilling-induced and core-handling fractures. Hydraulic fractures were found to be most abundant in the section of core closest to the stimulated wells. Significance: Benefits from an experiment of this type are: (1) Hydraulic fractures are observed directly, allowing fracture density and spatial distribution to be quantified. (2) Twist hackles on hydraulic-fracture surfaces may provide information about the direction of fracture propagation. (3) The degree to which natural, sealed fractures have been reactivated may be assessed. (4) Proppant distribution in the fractures can be examined. (5) Details of the observed hydraulic-fracture network can be used to verify, or provide input data for, models of hydraulic-fracture growth and proppant distribution. (6) Findings can provide ground truth for indirect diagnostic techniques such as microseismic monitoring. (7) Fractures in core and image log in the same well can be compared, and findings used to help calibrate other horizontal well image logs.},
doi = {10.15530/urtec-2018-2902624},
journal = {},
number = ,
volume = ,
place = {United States},
year = {2018},
month = {7}
}

Conference:
Other availability
Please see Document Availability for additional information on obtaining the full-text document. Library patrons may search WorldCat to identify libraries that hold this conference proceeding.

Save / Share: