Powered by OpenAIRE graph
Found an issue? Give us feedback
addClaim

Optimized Fracture Stage and Perforation Placement in Horizontal Wells using a New Calibrated Pulsed-Neutron Log Workflow

Authors: Jeff Dahl; James Samaripa; John Spaid; Erek Hutto; Dan Buller; Bill Johnson; Chris Mcilroy;

Optimized Fracture Stage and Perforation Placement in Horizontal Wells using a New Calibrated Pulsed-Neutron Log Workflow

Abstract

Abstract Evidence continues to mount to indicate that the geometric placement of fracture stages and perforation clusters in horizontal wells results in variable well production, with many clusters contributing little or no production. Any engineered completion design should require stages to be segregated by similar petrophysical and mechanical properties. The authors propose to reduce the cost per barrel of oil equivalent (BOE) and to improve estimated ultimate recovery (EUR) by using a novel log-derived completion method to better select perforation clusters and stage location to provide better fracture placement. A low-risk, pumped down, cased-hole pulsed-neutron log (PNL) is used after the well is cemented before completion. Using readily available geosteering software, the geologic projection of vertical well log measurements and the interpreted formation properties along the horizontal well enable a rigorous calibration method for PNL interpretation. Inelastic pseudodensity, neutron porosity, and resistivity-sigma calibrations can then generate a cased-hole triple combo. Elemental yields for silica, calcite, and potassium are used with additional clay inputs for a basic mineralogy interpretation. These inputs, within a specialized workflow, calculate a “production index” and “frac index” used to generate custom staging designs. Experience in a major unconventional play has shown a dramatic reduction in the number of stages and the completion cost per well. In addition, data from producing wells, using a software-derived stimulation design, has been matched to geometrically staged wells in the area. The addition of PNL data to interpret the position of the lateral well has been observed to reduce uncertainty when compared to the logging while drilling (LWD) gamma ray (GR) alone. The completion results for stages also provide good evidence that the overall efficacy of the stimulation treatment was increased by the perforation placement. The conclusions from this work show substantial completions cost savings per well while maintaining overall EUR in a difficult unconventional shale play. Based on pressure observations during stimulation, it is believed that stimulation efficiency has been increased. Using fewer stages to target the more productive rock and perforation clusters to target the sweet spots for stimulation has provided a substantial cost/BOE reduction. Although the technology for using a PNL log in the horizontal well has been attempted previously, there was not the benefit of a rigorous calibration method. The geologic projection of vertical wells is a novel approach to calibrate thousands of feet of logged PNL data. In addition, the custom staging design uses a novel, unbiased approach to select the optimum stage and perforation placement to minimize completions cost while maximizing productivity.

Related Organizations
  • BIP!
    Impact byBIP!
    selected citations
    These citations are derived from selected sources.
    This is an alternative to the "Influence" indicator, which also reflects the overall/total impact of an article in the research community at large, based on the underlying citation network (diachronically).
    3
    popularity
    This indicator reflects the "current" impact/attention (the "hype") of an article in the research community at large, based on the underlying citation network.
    Average
    influence
    This indicator reflects the overall/total impact of an article in the research community at large, based on the underlying citation network (diachronically).
    Average
    impulse
    This indicator reflects the initial momentum of an article directly after its publication, based on the underlying citation network.
    Average
Powered by OpenAIRE graph
Found an issue? Give us feedback
selected citations
These citations are derived from selected sources.
This is an alternative to the "Influence" indicator, which also reflects the overall/total impact of an article in the research community at large, based on the underlying citation network (diachronically).
BIP!Citations provided by BIP!
popularity
This indicator reflects the "current" impact/attention (the "hype") of an article in the research community at large, based on the underlying citation network.
BIP!Popularity provided by BIP!
influence
This indicator reflects the overall/total impact of an article in the research community at large, based on the underlying citation network (diachronically).
BIP!Influence provided by BIP!
impulse
This indicator reflects the initial momentum of an article directly after its publication, based on the underlying citation network.
BIP!Impulse provided by BIP!
3
Average
Average
Average
Upload OA version
Are you the author of this publication? Upload your Open Access version to Zenodo!
It’s fast and easy, just two clicks!