Colorado School of Mines Hosts Online Fall 2020 Reservoir Characterization Project

The Colorado School of Mines Reservoir Characterization Project (RCP) recently held its Fall 2020 meeting via a Zoom conference call featuring field projects from across the globe. 

RCP, part of the Department of Geophysics at the Colorado School of Mines in Golden, Colo., is an independently funded geophysical research consortium dedicated to the study of integrated reservoir characterization. The group, widely recognized as an early leader in advancing research of key technologies for 4D multi-component seismic applications, held its second, but just as successful, meeting in the same virtual manner as the Spring 2020 program due to the COVID-19 pandemic.

RCP Co-director Ali Tura said this year’s program included eight master degree students and eight doctorate degree students from diverse groups at the school including geophysics, reservoir engineering, geology and physics.

Of the 16 students that participated, six are from the U.S. and 10 of them are international students representing Kazakhstan (two students); Bangladesh; Taiwan; Brazil; Turkey; China (two students) and Russia (two students). According to Tura, many students are hired for internships with the many corporate sponsors of RCP.

Phase eight of the RCP program featured field projects, including data and analysis, from the Chalk Bluff project in the Hereford Field within the Denver-Julesburg (D-J) Basin, the Edvard Grieg Field offshore Norway as well as technical data investigations in various portions of the western U.S., the Gulf Coast (Eagle Ford), the Permian Basin, Brazil and the Middle East. 

Most, if not all, of the research directly impacts the sponsoring companies including data analysis and modeling and software development, according to Tura. She added the RCP program “encourages students to learn professional development practices and allows them to release their software developed during the research.”

Tura also noted the industry recognition of the students and their presentations including:

• 10 SEG presentations plus European Association of Geoscientists & Engineers (EAGE), SPE/URTEC presentations
• Six journal papers submitted
• Five Thesis/Graduations in 2020 (master’s program)
• Halliburton Best Thesis Award (Adam Tuppen)
• Six scholarships presented from SEG/AGI, Chevron and Equinor

Chalk Bluff Development Optimization Project

The Chalk Bluff project is a study of the Hereford Field in the D-J Basin in northern Colorado and southern Wyoming and north of Wattenberg Field. Researchers are targeting Codell Sandstone and Niobrara (B) Chalk to increase knowledge of Chalk Bluff to determine the optimal parameters for subsequent development and redevelopment.

“We are studying legacy wells and current wells being drilled by HighPoint Resources,” said student Ali Doward.

Doward also said that they want to generalize the findings in Hereford Field because “we also want to apply the generalized learning to other unconventional reservoirs such as Eagle Ford and the Permian Basin.”

Between 2009 and 2015, EOG Resources Inc. completed 3D seismic surveying and drilled a number of producing wells. The area was sold to Fifth Creek Energy in 2016 and the company developed Niobrara and Codell producers. In 2018, HighPoint Resources Corp. acquired the acreage and drilled and completed 23 horizontal wells.

The team project approach will utilize a number of data sets including 3D seismic, production data and petroleum system analysis, digital fracture injection testing (DFIT) and microseismic data from cemented fiber optic cable and digital acoustic sensing (DAS) and distributed temperature sensing (DTS). The team will perform lab analyses and interpretation of the data to optimize Niobrara and Codell development and production by evaluating fracture geometry, well spacing, completion parameters, fracture efficiency, reservoir heterogeneity and legacy well effects.

Doward said that a couple of the most important things from this project will be to characterize the geologic heterogeneity (sweet spot, reservoir thickness and fluid-rock interaction) because it could potentially impact well performance. Also important for the study, is characterizing natural and induced fractures.

Geology student Chad Taylor noted that well production variations during field development alone do not help to identify sweet spots. 

Taylor noted that field development observations to date suggest that rock properties alone do not solely define the sweet spot areas. “It’s going to be a multitude of things and a multiple of disciplines overlain to really understand what makes the sweet spots work in this area,” he said.

Balnur Mindygaliyeva worked on the production data for rate transit analysis to calculate the effective formation permeability for well stimulation and generating microfractures that might affect the performance of the reservoir. She examined a variety of methods including high- and low-frequency DAS and surface arrays, DTS, injection and petroleum system analyses.

Nurbol Bekbossinov used DFT data to examine how different stimulation designs can affect production performance from newly drilled wells in the project.

Rosie Zhu studied the low-frequency DAS data and looked at how intersecting fractures can be located along a monitor well and then be used to estimate the fracture azimuth length and vertical growth of the fractures in the treatment well.

Harrison Schumann looked at how two waves following the perforation shots recorded on DAS data may provide insights to the near-well conductivity of the hydraulic fracturing and allow stage-by-stage comparisons. 

Currently, the team is analyzing the data and attribute extraction phase and are beginning to integrate their results to understand the field’s complexity. According to  Schumann, “The team will be looking at all of the data to develop a multi-resolution and analysis to understand the optimal well spacing, completion design and well landing to increase production for future developments.”

Edvard Grieg Field Project, Norwegian North Sea

The Edvard Grieg Field is in the Utsira High area in the Norwegian North Sea. Discovered in 2007, it currently has gross 2P ultimate recovery of 350 MMboe.

There is significant further upside in the greater Edvard Grieg area, where the total gross ultimate resource potential is estimated to be 800 MMboe, which includes upsides to existing fields and unrisked prospective resources.

Masters student Mari Held is working with field operator Lundin Energy. The Swedish independent E&P company has 10 producing wells in the field and has four water injector sites. The company plans to drill four new wells this year and install fiber optic cabling into three wells.

In the project area, the producing wells are to the east in the up-dip part of the field and the injector wells are to the west.

A previous 4D joint PP-PS pre-stack inversion study in the field between 2016 and 2018 using PP and PS data, monitored pressure and saturation. Held plans to again monitor the pressure and saturation data and the total change from 2016 to 2020 based on joint PP-PS pre-stack inversion.