To improve initial production and ultimate recovery, we must first fully understand the reservoir rock. Full-gauge coring is the first line-of-sight into a reservoir. The actual formation samples recovered at the surface are the “groundtruth” that provides the basis for accurate reservoir evaluation and modeling. Cores are almost always acquired—and in many countries are required—for exploratory wells. They also are taken in development wells, even in well-known areas, to help operators better understand or confirm that the reservoir rock in one well exhibits the same characteristics as in previous wells. The larger the core size, the better for core analysis, because more information about the formation can be gathered in less time. Additionally, a core with larger dimensions means less, easier-to-mitigate invasion into the zone of interest, so better plots can be made. Download the PDF to read more.