The Milne Point field in Alaska produces from the Kuparuk, Schrader, and Ugnu formations. The Kuparuk formation contains light oil, while the Schrader and Ugnu contain heavy oil. The ranges of viscosities are 200 to 10,000 cp in the Ugnu, 20 – 200 cp in the Schrader, and about 3 cp in the Kuparuk. Over 200 wells have been completed in the Kuparuk and Schrader formations at Milne Point. The Ugnu contains the largest oil in place in the field; however, it has not been developed yet due to the high oil viscosities. To date, only one well has been completed in the Ugnu. BP is engaged in new studies to find a way to make the Ugnu commercial. This paper discusses an attempt to identify lower-viscosity “sweet spots” within the Ugnu using nuclear magnetic resonance (NMR) measurements. In 2004, full suites of logging while drilling (LWD) and wireline data were acquired in two newly drilled wells. The primary goal was to compare viscosity predictions from NMR log measurements to geochemical measurements made on fluids extracted from core plugs. For the first time, on a foot-by- foot basis, using LWD NMR, lower viscosity sweet-spots were identified in the viscous Schrader formation and in the very heavy oil in the Ugnu formations.
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