High-grade paraffin oil is reported to have been discovered in the western part of the Olympic Peninsula, Wash., as early as 1881. Since then attempts to obtain oil or gas in commercial quantities by drilling have been made from time to time in different localities in this region, but without success. Within the past few years interest has been aroused in oil seeps near the mouth of Hoh River and in gas vents in other parts of the field to such an extent that many persons have been attracted to this country to search for oil and gas. As a result of this interest and on account of the fact that efforts had been made to lease tracts of land for this purpose in the Queniult Indian Reservation, an examination of this region was made by the United States Geological Survey at the request of the Office of Indian Affairs. The results of the investigation, which are enumerated below and which are discussed in detail throughout this report, suggest that certain parts of the field are worthy of careful consideration by oil operators. The following summary includes the most important facts regarding the area examined: High-grade paraffin oil issues from two seeps near the mouth of Hoh River, and at other localities oil-saturated sandy clay ('smell mud' of the Indians) is exposed. Natural gas containing about 95 per cent methane escapes from a conical mound just north of the mouth of Queniult River and also from an inverted cone-shaped water-filled depression on Hoh River a short distance west of Spruce post office. Other minor gas vents are also known in this field and are described in detail in this report. Three wells - one in the reservation about 1 mile north and slightly west from Taholah, another near the mouth of Hoh River, and the third about 1 mile south of Forks - are being drilled for oil and gas. So far as drilling has progressed none of these wells have encountered oil in paying quantities, but all of them have struck small amounts of gas. A study of the structure and stratigraphy in addition to the examination of oil seeps and gas vents reveals the fact that several anticlines, which may serve as reservoirs for oil and gas, exist in the area examined and that they have apparently a close relationship to the oil seeps and occurrences of 'smell mud'.