DISTINGUISHED SEMINAR SERIES: Dave Cramer, ConocoPhillips Company

This presentation covers the essential elements of limited entry treatment design and reviews a case study of plug-and-perf horizontal well treatments in an unconventional shale play. In the case study, various diagnostic methods were used to better understand and quantify the factors determining limited entry effectiveness. Three diagnostic methods were implemented: 1.) injection step-down tests and pressure analysis of the fracturing treatments, 2.) video-based perforation imaging and 3.) distributed acoustic sensing (DAS).

In-situ stress variation and perforation erosion were determined to have significant impacts on treatment allocation among perforation clusters. Other undesirable effects such as heel-side flow preference were also observed. Camera images confirmed proppant-induced erosion at the scale of individual perforations. Measurements from the digital images provided comparison points for predictive software using surface pressure measurements. DAS results provided cluster level proppant distribution values. Correlations were also observed between treatment allocation values from DAS data and values derived from perforation friction calculated from Bernoulli’s equation using the image-based entry hole diameter data.

The results of the case study indicated that a staggered perforation design using more gradual changes among clusters would lead to a more balanced treatment. This scenario was evaluated along with a job design featuring high excess perforation friction and an equal number of perforations in each cluster. Fracture-simulation runs indicated that both tactics are likely to improve slurry allocation.

Bio:

Dave Cramer is a Senior Engineering Fellow on the ConocoPhillips Global Completions Engineering staff in Houston, TX and specializes in hydraulic fracturing applications and pressure analysis.  He has published 69 technical papers and holds two U.S. patents and one provisional U.S. patent. He is a registered Professional Engineer in Colorado. Dave has been selected as an SPE Distinguished Lecturer on two occasions, in 2003-2004 and for the current 2021-2022 campaign. He was the SPE Region Director for the U.S. and Canada Rocky Mountain region from 2004-2007. His industry recognitions include the SPE International Cedric K. Ferguson Certificate (2020), SPE International Distinguished Member Award (2019), SPE International Completions Optimization and Technologies Award (2011), and SPE Denver Section Henry Mattson Technical Achievement Award (1993).