WorldWide Drilling Resource

36 FEBRUARY 2018 WorldWide Drilling Resource ® Cores from the Past Lead to a Bright Future Adapted from Information by the Unites States Geological Survey For more than 40 years, the United States Geological Survey (USGS) has been operating a rock core and cuttings repository in Denver, Colorado. To dis- cover geologic resources, it is necessary to see what is hidden deep beneath the earth’s surface. The USGS, along with the petroleum and mining industries, produce cores and cuttings while searching for en- ergy or mineral deposits. These scientif- ically important geological resources are preserved, and publicly available for study. The USGS Core Research Center (CRC) has a collection of rock cores from more than 9000 wells, and cuttings from more than 52,000 wells. What’s the difference? Well, rock cores are cylindrical sections of rock brought to the surface for study. These cores provide a record of rocks which can be examined for its physical and chemical features. Cuttings, on the other hand, are sand-like particles produced by a rotary bit as the borehole is being drilled. They too, can also be studied to learn about the composition of the underlying geological formations. The CRC collection contains samples from 33 states with the majority of them originating from the Rocky Mountain region and adjacent states. Each year, up to 1800 researchers from industry, academia, the USGS, and other government agencies use the climate-controlled examination rooms at the CRC to broaden their understanding of the earth beneath us. Most private companies keep cores and cuttings for their exclusive use while developing a prospect. Eventually though, storage becomes a burden and cores are oftentimes donated to the CRC. Old cores and cuttings in the collection have given researchers the ability to reanalyze areas of interest, which has led private industry geologists to new discoveries of valuable natural resource reserves. For example, a core drilled in 1991, in Colorado’s Niobrara Formation in the Denver Julesburg Basin, was recently linked to a major oil discovery. Technology at the time the core was drilled was not capable of bringing the project into production, so the core was donated to the CRC. In 2009, the core was used as part of an industry study to determine the viability of using horizontal directional drilling techniques, which had been very suc- cessful in the Bakken Formation in North Dakota. Findings from the core, along with 3-D seismic data, justified the con- siderable expense of drilling three test holes in the area. Not only were the test holes productive, which led to drilling 71 horizontal wells in the immediate vicinity, it also led to the development of more than 4400 horizontal wells in the area. This is just one of many examples of new resource discoveries based on analyses of old cores. Next month we’ll examine how the CRC collection is used for discovering and evaluating water resources. Rock Cores Cuttings Congratulat ions to: Uldis Jansons Lakewood, CO Winner for January! Winn r ary Time for a Little Fun! January Puzzle Solution: Aardvark Packers Baroid Industrial Drilling Products Win a prize! Send your completed puzzle to: WWDR PO Box 660 Bonifay, FL 32425 or fax to: 850-547-0329 Can you identify which ads in this issue these two photos came from?