Oil and Gas Assessment of the Utukok Special Management Area, National Petroleum Reserve in Alaska

The Uiukok Carihu/Grizzly Special Management Area (USMA) and the Utukok Caribou Deleted Area (UCDA) in the western part of the National Petroleum Reserve in Alaska have a low probability of having economically recoverable oil and gas resources based on BLM classification standards in Handbook H-1624-1.

The shallow potential reservoir rocks in the area are thin and have low porosity and permeability values, at least as exposed at the surface and in the nearest wells. The deeply buried potential reservoir rocks appear to be below the oil preservation window, and any hydrocarbons that they may contain would probably be natural gas. The source rocks in the area tend to have low organic carbon content of a gas-prone nature. No subsurface geological data exists for the area, but extrapolations from the surface geology, from the subsurface geology of the nearby test wells, and from reflection seismic data hold little promise for the oil and gas potential of the USMA and UCDA areas.

While the available data shows little promise for the area, subsurface data from within the area and new exploration concepts could change the assessment presented here. In this regard, it should be emphasized that no wells have been drilled within the confines of the USMA or the UCDA, that is, this area has not been evenly lightly explored for oil or gas.

Remote even by north slope standards, nothing of the known fold and thrust belt structural style characterizing southwestern NPRA's geology distinguishes its petroleum potential from less environmentally sensitive NPRA areas to the north and east. In fact, interpretation of the United States Geological Survey 1988 Alaskan north slope hydrocarbon assessment suggests southwestern PJPU is the least hydrocarbon rich part of the Reserve.