Geological Survey Bulletin 581—B Oil and Gas in the Western Part of the Olympic Peninsula, Washington

ROCKS EXPOSED ALONG QUENIULT RIVER AND LAKE.

At location A, on the south side and about 1-1/2 miles from the mouth of Queniult River, 400 to 500 feet of soft yellowish sandstone and conglomerate are exposed. The pebbles in the conglomerate consist of hard material stained brown and the largest are 6 inches in diameter. These beds, which dip 23° E. and strike N. 8° E., are believed to be a part of the Queniult formation, which is well exposed along the coast both north and south of the mouth of Queniult River. The same formation is exposed on the north side of the river at location B, about one-half mile east of location A. At this place a little fine grained conglomerate, capped with slightly consolidated Pleistocene rocks, outcrops a short distance above water level. The strata dip 17° SE. and strike N. 15° E. Southeast of location B several feet of Pleistocene sand and clay is exposed at location C, on the east side of a small creek emptying into Queniult River from the north. At location D, on the south side of the river, in the SE. 1/4 sec. 6, T. 21 N., R. 12 W., very soft, poorly consolidated sand and conglomerate, similar to those beds described at location A, are well exposed for a short distance. At this place there is a fault and an abrupt flexure of the strata. The fault trends N. 30° W. and is nearly vertical. About 20 feet east of the fault the strata dip 70° NE. and strike approximately N. 60° W., but 50 feet farther east the beds flatten to a dip of about 20°. Southwest of the fault, along the south side of the river, there is a very prominent slide 300 or 400 feet in width, composed of soft blue mud, but no indications of petroleum gas were noted. The exposure of soft bluish sandy mud is bounded on the northwest by a conspicuous outcrop of fairly well consolidated sandstone and conglomerate approximately 125 feet thick. It is probable that a fault separates these beds from the slide, although no definite evidence was obtained regarding it. All the beds at location D are unconformably overlain by beds of Pleistocene sand, clay, and gravel.

For several miles up the river no Tertiary or older rocks are exposed, but at various places described below the beds of Pleistocene age outcrop and in places contain not only the characteristic clay, sand, and gravel but also thin beds of very impure lignite. This material can hardly be considered lignite, but might more properly be classed as peat. However, the term "lignite" has been already used in this report and hereafter wherever it occurs it will be understood as applied to this very poor peatlike material.

At location E, on the north side of the river opposite Billy Snell's place, a cut bank exposes several feet of bluish sandy clay overlain by a little lignite and unaltered wood, which in turn is overlain by about 25 feet of yellowish-gray conglomerate. The pebbles of this conglomerate consist principally of smooth subangular fragments of metamorphic rocks. In places the bowlders reach a maximum size of 18 inches, but for the most part they are less than 6 inches in diameter. At location F, about 1-1/4 miles upstream from location E, beds of Pleistocene age are exposed on the south side of the river for a short distance, and again at location G in the NE. 1/4 sec. 3, T. 21 N., R. 12 W.

Probably the most prominent exposure of the Pleistocene along the whole course of Queniult River is found at location H, northeast of John Chowchow's place. The bluff on the north side of the river at this place is about 300 feet high, and consists of poorly consolidated yellowish sandstone and grayish conglomerate with a little bluish-gray sandy clay. A detailed measurement of these strata was not made, but from the fairly large pieces of lignite found in the talus near the water's edge it is believed that a lignite bed 1 to 2 feet thick is present in the upper part of the bluff. The beds lie practically flat. The ridge into which Queniult River now impinges to form this prominent bluff trends approximately N. 10° E., but it is not present near the stream on the south side of the valley.

At location I, about 1 mile northeast of location H, on the south side of the river and also southwest of the mouth of a small creek, a bed of resistant dark-gray sandstone overlain by sandy shale is exposed a short distance above the water. This exposure is of small extent and is believed to be the easternmost outcrop of the Queniult (?) formation on Queniult River, but it may be part of the "supposed Cretaceous" formation, in which case it is necessary to assume the presence of a fault or a fold lying to the west. The strata here dip approximately 43° NE. and strike N. 70° W. Between location I and Burnt Hill (location R, described below), a distance of about 15 miles by the river, no rocks older than Pleistocene are exposed along the river banks. These exposures are described hereafter, together with certain indications of the presence of older rocks near the surface.

At location J, on the south side of the river, about one-third mile west of Tommy Ford's place, about 15 feet of bluish sandy clay, overlain by approximately 20 feet of poorly consolidated conglomerate, is exposed for a short distance. At location K there is a large rapids locally known as Bookrock Rapids, in which numerous large bowlders and angular rocks suggest the existence of a ridge or ledge of metamorphic rocks near the surface at this place, unless they have been carried here by the glaciers from Olympic Mountains. A very large erratic at location O, on Queniult River, described below, suggests that these large fragments of rock were brought by ice.

Just upstream from Bookrock Rapids, on the south side of the river, dark-bluish sandy clay about 15 feet thick, overlain by poorly consolidated sand and gravel about 40 feet thick, both of Pleistocene age, is exposed for a short distance. Another very striking exposure of Pleistocene rocks occurs at location L, on the north side of the river, approximately in the NW. 1/4 sec. 21, T. 22 N., R. 11 W. The greater part of this consists of almost flat-lying beds of bluish sandy clay, sandstone, and conglomerate, as shown by the following section:

Pleistocene beds exposed at location L, on Queniult River.

The section above described gives an idea of the thickness of the beds overlying the entire area west of the Olympic Mountains. The bluff in which these strata are exposed is 600 or 700 feet long. At location M, on the south side of the river, about one-half mile west of the mouth of Cook Creek and about 2 miles upstream from location L, there is a bluff 40 to 60 feet high in which bluish clay mixed with sand, gravel, and bowlders, the largest of which are 1 foot in diameter, is exposed in the lower 30 feet of the outcrop. Just above this bluish clay about 10 feet of grayish conglomerate is exposed.

The lower course of Cook Creek was examined as far east as location N, a distance of more than a mile. The rocks outcropping along this portion of the stream are either of Pleistocene or Recent age and consist of poorly consolidated clay, sand, and conglomerate. The banks of the creek are not more than 15 feet high and are covered to the water's edge with a very dense growth of timber and underbrush.

At location O, on the south side of Queniult River and about three-fourths of a mile from the mouth of Cook Creek, there is a large rock approximately 25 feet long, 15 feet wide, and 15 feet high. This rock is very hard and resistant and is similar to that exposed at Burnt Hill, about 6 miles upstream, hereinafter described. It was impossible to determine whether or not this rock is in place, but as no other rocks of similar composition are exposed near by it seems probable that it is an erratic. Its presence here, together with the large bowlders described in the vicinity of Bookrock Rapids, 5 or 6 miles below, suggest strongly that glaciers from the Olympic Mountains extended to this locality and brought these immense fragments of rock at least from the vicinity of Burnt Hill if not from the main range east of Queniult Lake.

A short distance upstream from location O, and on the north side of the river, a cut bank exposes about 50 feet of poorly consolidated cross-bedded conglomerate of Pleistocene age. At location P, about one-half mile southwest of the mouth of Boulder Creek, approximately in the western part of sec. 14, T. 22 N., R. 11 W., blue clay of Pleistocene age is also exposed. As large quantities of this clay occur at many places along the streams several miles inland it is suggested that it may be valuable for the making of bricks. It has not been tested, but is believed to be worthy of examination by those interested in such materials. Owing to its location it is not of value at the present time, but in the future, when this region may be rather densely settled, it probably will be of considerable importance.

The Pleistocene beds are well exposed at location Q, on the north side of Queniult River, a short distance northeast of the mouth of Boulder Creek. At this place the lower part of the Pleistocene exposure consists of very fine bluish clay and the upper part of a poorly consolidated conglomerate. There is a marked local unconformity separating the two. The upper 4 inches of clay underlying the conglomerate is stained yellowish gray with iron, which is the principal cementing material of the overlying conglomerate.

No extensive exposures were noted between location Q and location R on the north side of Queniult River, approximately in secs. 1 and 12, T. 22 N., R. 11 W. Location R is locally known as Burnt Hill on account of the vegetation having been burned several years ago. The rock, probably greenstone, exposed in Burnt Hill is dark greenish gray and belongs to those rocks of the Olympic Peninsula that have been designated the old metamorphic series. In places the fractures and joints have a purplish color, but where the rock is much weathered the color is lighter and has somewhat of a greenish tinge. Two sets of joints cut the rock, one trending N. 55° E. and dipping about 77° NW., and the other trending N. 85° E. and dipping about 80° N. The smooth rounded surface of Burnt Hill suggests that it has been glaciated.

At location S, on the north side of the river, in the S. 1/2 sec. 5, T. 22 N., R. 10 W., Pleistocene conglomerate approximately 100 feet thick is exposed. At location T, in the S. 1/2 sec. 35, T. 23 N., R. 10 W., about 3-1/2 miles upstream from location S and about one-half mile east of Shortys Rapids, large amounts of bluish sandy clay are exposed on both sides of the river. The clay is very distinctly bedded and quite soft and slippery when wet. At location U, locally known as the Blue Banks, about 1-1/2 miles upstream from location T, 40 to 60 feet of bluish sandy clay containing thin lenses and beds of gravel overlain by yellowish-gray poorly consolidated conglomerate 30 to 40 feet thick is exposed. The conglomerate is well stratified and dips slightly to the west. Farther up the river, at location V, which lies between location U and the west end of Queniult Lake, the beds of Pleistocene sand and gravel dip to the west at angles as high as 30°. As stated under the heading "Topography" (p. 36) it is believed that without question the Pleistocene deposits in the vicinity of Queniult Lake are of glacial origin and that the lake itself is due to the presence of a prominent terminal moraine crossing the valley in a northwest-southeast direction through the southeastern part of T. 23 N., R. 10 W. The glacial deposits are known to surround the western part of Queniult Lake and are believed to extend for several miles both to the northwest and southwest from the lake. At the northeast end of the lake apparently glaciated metamorphic rocks are exposed and they also show at location W, about one-fourth of a mile west of Higley's hotel. The outcrop at this place is known locally as Onion Rock from its very smooth surface, which is probably the result of glaciation. Two other exposures of similar rock were seen on the same side of the lake and about 1 mile west of Higley's hotel. The remainder of the rocks surrounding Queniult Lake, as far as the writer is aware, belong to the poorly consolidated beds of clay, sand, and gravel of Pleistocene age.

The gas which issues from the water near the upper end of the lake and also near the bridge over Canoe Creek at Higley's hotel escapes through beds of Pleistocene and Recent age.

To summarize, metamorphic rocks are exposed along Queniult River and Queniult Lake at two localities—one at Burnt Hill, in secs. 1 and 12, T. 22 N., R. 11 W., and the other on the north side of Queniult Lake in the vicinity of Higley's hotel. One of the most conspicuous of these outcrops on the lake is known as Onion Rock.

The rocks exposed at locations A, B, D, and I are believed to be outcrops of the Queniult formation, although it is possible that the exposure at location I is composed of "supposed Cretaceous" rocks.

All other exposures along Queniult River and Queniult Lake are believed to be of Pleistocene and Recent age.