C)~ A, ~ u State of Washington 6 ....0 0 Department of Natural Resources Ill C) BERT L. COLE, Commissioner of Public Lands

DIVISION OF MINES AND GEOLOGY MARSHALL T. HUNTTING, Supervisor

Geologic Map GM-4

GEOLOGY OF THE GRAYS RIVER QUADRANGLE, WAHKIAKUM AND PACIFIC COUNTIES, WASHINGTON

By

EDWARD W. WOLFE and EDWIN H. McKEE U. S. GEOLOGICAL SURVEY

Prepared cooperatively by the U.S. Geological Survey

STATE PRINTING PLANT ~ 3 OLYMPIA, WASHINGTON

1988

For sole by Deportment of Natural Resources, Olympia, Washington. Price, $1.00 STATE OF WASHINGTON TO ACCOMPANY GEOLOGIC MAP GM-4 DEPARTMENT OF NATURAL RESOURCES DIVISION OF MINES AND GEOLOGY GEOLOGY OF THE GRAYS RIVER QUADRANGLE, WAHKIAKUM AND PACIFIC COUNTIES, WASHINGTON

By Edward W. Wolfe and Edwin H. McKee

INTRODUCTION middle Eocene (Ulatisian age of Mallory, 1959) or The Grays River quadrangle is in southwestern possibly earliest late Eocene ( early Narizian age of Washington on the north side of the Columbia River Mallory, 1959) age. The Crescent Formation is litho­ approximately 20 miles upstream from the river logically correlative with the lower part of the early mouth. Mild climate and heavy rainfall (approxi­ to middle Eocene Siletz River Volcanic Series of the mately 115 inches per year just west of the map area Oregon Coast Range (Snavely and Baldwin, 1948). at Naselle) produce lush vegetation and deep and UNIT A intensive weathering. Previously published geologic work in the Grays Overlying and perhaps intertonguing locally with River quadrangle is limited to the pioneering studies the upper part of the Crescent Formation is a unit, of C. E. Weaver. His monograph on the Tertiary informally designated unit A, of siltstone and in­ stratigraphy and paleontology of western Washington tcrbedded sandstone that may be as much as 2,000 and northwestern Oregon (1937) includes a generalized feet thick. The unit is exposed in the northwestern geologic map of the Grays River area. More recent and northeastern parts of the quadrangle. detailed geologic studies of nearby areas in southwest­ Siltstone in unit A is well indurated, thin bedded, ern Washington (Henriksen, 1956; Pease and Hoover, and dark gray where freshly exposed. It consists of 1957; Rau, 1958; Snavely and others, 1958; Gower angular silt-sized quartz, feldspar, and lithic grains, and Pease, 1965; Livingston, 1966; H. C. Wagner, in as well as minute mica flakes in a chloritic or vermic­ press) do not include the area of the Grays River ulitic matrix. quadrangle, but they deal with stratigraphic sequences Sandstone forms beds ranging in thickness from closely related to the succession in this quadrangle. less than a foot to more than 1 O feet. In fresh expo­ Geologic mapping was carried out by E. W. Wolfe sures the sandstone is greenish gray, but in most and E. H. McKee, of the U. S. Geological Survey, in outcrops it is weathered to yellow or brown. The the summers of 1963 to 1966 as part of a cooperative sandstone is very fine to medium grained and has program with the State of Washington Division of abundant interstitial clay and randomly scattered Mines and Geology. Weldon W. Rau, of the Division, mica flakes. Locally the sandstone contains coarser made all foraminifcral determinations and correla­ sand and granules. The sandstone beds typically have tions; all molluscan identifications and correlations no visible internal structure. Graded bedding can be were made by Warren 0. Addicott, of the U. S. seen in some outcrops, but usually it is difficult to Geological Survey. Assistance in the field by A. R. recognize because of the absence of coarse detritus. Brown in 1963, M. D. Himes in 1964, W. G. Gilbert in Small-scale crossbedding occurs locally. The basal 1965, and N. S. MacLeod for part of the 1966 field contacts of the sandstone beds are always sharp; sole season is gratefully acknowledged. marks are rarely found. North of Swcigiler Creek, in the eastern part of the STRATIGRAPHY quadrangle, interbedded siltstone and sandstone have CRESCENT FORMATION been mapped with unit A. The sandstones in this area The oldest rock unit exposed in the Grays River arc volcanic sandstones containing grains of plagio­ quadrangle is a sequence of basaltic rocks called the clase and basalt. They occur as individual beds rang­ Crescent Formation in accordance with the usage es­ ing from a few inches to about 2 feet in thick1wss tablished by Gower (1960). The sequence crops out in and some are graded. · ' the relatively rugged highland areas in the northwest­ Foraminifera from unit A in the north-central part ern and northeastern parts of the quadrangle and is of the quadrangle indicate an age of late middle probably more than 5,000 feet thick. Eocene (late Ulatisian age of Mallory, 1959) or possi­ The Crescent Formation is predominantly aphanitic bly earliest late Eocene (early Narizian age of Mal­ to fine-grained pillow basalt, although massive and lory, 1959). columnar-jointed basalt as well as aquagene tuff and UNIT B siltstone occur locally. The pillows are well defined The next younger rock unit, informally designated range from about 1 to 3 feet in diameter, and ar~ unit B, consists of several thousand feet of sedimentary characterized in cross section by well-developed radial and volcanic rocks. The absence of distinctive marker jointing. In fresh exposures the pillow basalt looks beds and lack of knowledge of the structural details greasy, possibly because of abundant altered glass. precludes a precise determination of the thickness, but Locally the basalt is amygdaloidal. a thickness of more than 5,000 feet seems likely. The Foraminifera from siltstone interbeds in the Crescent contact with the oloer rocks, where exposed, is a Formation of the Grays River quadrangle indicate a fu~ . 1 The most widespread rock type in unit B is marine Ha-Chehalis district (Snavely and others, 1958), con­ tuffaceous siltstone, which is well indurated, well sidered as a group, are correlative with unit B. stratified, and is generally gray or greenish gray. Cal­ careous concretions are common and range from LINCOLN CREEK FORMATION spheres about an inch in diameter to elongate lenticu­ The most complete section of the Lincoln Creek lar masses as much as 1 foot thick and many feet Formation (Beikman and others, 1967) is exposed in long. Megafossils are rare, but Foraminifera are abun­ the southeastern part of the Grays River quadrangle. dant and are commonly visible in hand specimens. No obvious angular discordance is recognized between The volcanic rocks of unit B consist predominantly the Lincoln Creek Formation and the older rocks in of massive basalt flows of probable subaerial origin in the central part of the quadrangle, but relations east the Grays River valley and of aquagene tuff and flow of the Grays River valley suggest that the basal con­ breccia of marine origin in the Naselle River valley. tact is unconformable. Incompleteness of structural The massive flows of the Grays River valley consist data due to poor exposures precludes a precise deter­ of relatively fresh porphyritic basalt, and some tuff mination of the thickness, which undoubtedly varies and basaltic breccia. Their thickness is unknown, but because of overlap of the Lincoln Creek by the Asto­ it is probably at least 2,000 feet. Bright-red zones of ria(?) Formation. However, a lower limit for the oxidized tuff or altered basalt occur locally. At the thickness is obtained from the Richfield-Weyerhaeuser No. 1 well (located near the mouth of Deep River), base of the sequence the massive flows grade down­ which penetrated approximately 3,500 feet of strata ward into volcanic breccia, tuff, and volcanic sand­ that are correlated with the Lincoln Creek on the stone that are interbedded with marine siltstone of basis of Foraminifera. In the west-central part of unit B. the quadrangle, the Lincoln Creek Formation was not Basaltic rocks of submarine origin interfinger with recognized. However, unit B may include some strata marine tuffaceous siltstone in the Naselle River valley. equivalent to the Lincoln Creek mapped in the eastern They also crop out in the North Nemah River valley part of the area. in the northwest part of the quadrangle and near the The Lincoln Creek Formation consists predomi­ headwaters of Hull Creek in the east-central part of nantly of massive to indistinctly bedded tuffaceous silt­ the quadrangle. These marine volcanic rocks consist stone and contains a basal zone in which basaltic sand­ predominantly of structureless to distinctly bedded stone and glauconitic sandstone occur. Bedding is less aquagene tuff or, in places, of extremely amygdaloidal well developed in Lincoln Creek siltstones than in the basalt, basaltic sandstone, or siltstone rich in coarse underlying siltstones of unit B, although well-devel­ volcanic debris. N onamygdaloidal basalt, lithologically oped bedding occurs locally in the Lincoln Creek For­ similar to the massive flows of unit B in the Grays mation. The siltstone is well indurated in the lower River valley, is present locally in unit B in the Na­ part of the formation but becomes less indurated up­ selle River valley area. It occurs most commonly as ward. flow breccia, but in places it is pillowed or massive. Basaltic sandstone occurs in the lower part of the Small masses of volcanic rock mapped in unit B be­ formation; the basal contact is drawn at the base of tween Hull Creek and the Naselle River include mas­ this sandstone. The maximum development of this sive basalt as well as breccia and aquagene tuff; some sandstone occurs in the east-central part of the quad­ may be intrusive. rangle, in the vicinity of Fossil and Klints Creeks. Sandstone constitutes a minor part of unit B. A There the basaltic sandstone, which contains interbed­ massive, fine- to medium-grained, friable arenite ap­ ded siltstone, is about 800 feet thick. The sandstone is proximately 200 feet thick resting on the upper Eo­ medium light gray to olive gray or dark greenish cene volcanic rocks is mapped in the eastern part of gray, massive, very fine to fine grained, and in the the quadrangle. It grades upward into marine tuffa­ easternmost outcrops, where large clasts are coarsest ceous siltstone in the upper part of unit B. Similar and most abundant, it contains rounded grains of sandstone, as well as basaltic sandstone, occurs in basalt and glauconite up to half a centimeter in diam­ scattered outcrops elsewhere. In a few localities, par­ eter. Carbonized wood fragments occur locally. Mol­ ticularly in the north-central part of the quadrangle luscan fossils are abundant, and subspherical, base­ and in the Naselle River channel near the west edge ball-sized concretions commonly contain crab remains. of the quadrangle (sec. 12, T. 10 N., R. 9 W.), very Thickness of the sandstone unit, the proportion of fine-grained sandstone is interlaminated with siltstone. sandstone to siltstone, and the maximum grain size Parallel lamination that has concentrations of mica greatly diminish west of the Grays River valley. and carbonaceous detritus on the bedding surfaces is Tuffaceous siltstone, in part interlaminated with rel­ characteristic. Small-scale crossbedding occurs locally. atively well sorted very fine-grained sandstone, is ex­ Foraminifera represent the Bulimina cf. B. jackson­ posed in the headwaters of Klints Creek; in highway e nsis, Uvigerina cf. U. ya,zooensis, and Plectofrondic­ cuts at the east edge of the quadrangle; and in the itlaria cf, P. jenkinsi-Bulimina schencki Zones of Rau valley of Eggman Creek, just east of the quadrangle. (1958), of middle and late Eocene age (Ulatisian and Parallel lamination that has subordinate small-scale Narizian Stages of Mallory, 1959), and possibly the crossbedding and an abundance of mica and carbona­ Sigmomorphina schencki Zone (Snavely and others, ceous debris on the bedding surfaces characterizes the 1958). Rau (written communication, 1967) refers sandstone units. These strata are believed to be a local the latter zone to the lower part of the Refugian Stage facies of the lower part of the Lincoln Creek Forma­ of Schenck and Kleinpell (1936) and now tentatively tion. regards it as late Eocene in age. The McIntosh, North­ In the upper part of the formation, glauconitic, craft, and Skookumchuck Formations of the Centra- basaltic, and tuffaceous sandstone is abundant, al- 2 though subordinate in quantity to siltstone. Light-col­ Relatively clean sandstone in beds as thick as 160 ored tuft' beds occur locally. Glauconitic beds, some of feet is interbedded with typical argillaceous Asto­ which are more than 10 feet thick and which in many ria (?) strata on the ridge north of the Columbia River places are more than half glauconite, are common. A in the eastern half of the quadrangle. The sandstone discontinuous line drawn on the map indicates the is best exposed in outcrops north of Brookfield and on lowest known occurrence of glauconite or sandstone in the ridge above Fink Creek. It is very fine to fine the upper part of the formation. grained and contains sweeping crossbeds up to 6 feet Foraminifera from the Lincoln Creek Formation long. Similar sandstone between Altoona and Dahlia, represent the Sigmomorphina schencki (Snavely and along the bank of the Columbia River, is mapped as others, 1958), Cassidulina galvinensis (Rau, 1966), and Astoria(?) Formation, but it may be a younger unit Pseudoglandulina aff. P. infiata (Rau, 1958) Zones and reworked from the underlying Astoria(?) strata. indicate an Oligocene and possibly latest Eocene age A different and distinctive lithologic assemblage is (Refugian Stage of Schenck and Kleinpell, 1936, and mapped in the upper part of the Astoria(?) Formation Zemorrian Stage of Kleinpell, 1938) in the Grays west of Deep River. It occurs along the Columbia River quadrangle. River bank and on the ridge between Sisson and Mollusks from the lower sandstones are referable to Salmon Creeks in the southwestern part of the quad­ the Oligocene "Lincoln Stage" of Weaver and others rangle. The unit consists of more than 1,000 feet of ( 1944). Faunal groups corresponding to the Molopo­ bedded siltstone containing interbeds of very fine- to phorus gabbi and Turritella porterensis Zones of Dur­ very coarse-grained friable sandstone ranging in ham (1944) are recognized. Some of these strata also thickness from half an inch to 40 feet or more. The contain Sigmomorphina schencki Zone Foraminifera, sandstone forms beds and abundant elastic dikes that which Rau (written communication, 1967) tentatively intrude the surrounding sedimentary rocks. Light-col­ regards as late Eocene. ored tuffaceous beds ranging in thickness from about Megafossils from the upper part of the formation a sixteenth of an inch to 1 foot occur locally. The unit are referable to the Echinophoria rex and Echinopho­ as a whole is characterized by sparse crossbedding ria apta Zones (Dur.ham, 1944) of the "Blakely Stage" and extensive development of parallel lamination. The of Oligocene and Miocene ages (Weaver and others, lamination results from alternation of tuff and silt­ 1944). stone, alternation of sandstone and siltstone, or con­ ASTORIA (?) FORMATION centration of carbonaceous detritus in layers in other­ Siltstone and sandstone unconformably overlying wise massive sandstone. Locally, the sandstone also the Lincoln Creek Formation are referred to the contains beds of tabular pebbles and cobbles derived Astoria (?) Formation. The name "Astoria shales" was from the associated siltstone. originally applied by Condon (Cope, 1880) to fossilifer­ On the ridge south of Salmon Creek just west of the ous sedimentary rocks that were ·exposed in the vicin­ quadrangle boundary, a conglomerate composed of ity of Astoria, Oregon, but that have since been pebbles and cobbles of basalt is exposed in a single concealed by urban development. Other geologists outcrop. Sedimentary rocks above and below the con­ working in southwestern Washington (e.g., Pease and glomerate are similar to each other, except that the Hoov·er, 1957; Snavely and others, 1958) have used the overlying siltstone may be more tuffaceous and con­ name Astoria(?) Formation for lower or middle Mio­ tains abundant pumiceous granules and pebbles as cene strata underlying or interfingering with basalt of well as oxidized leaf fragments. Miocene age. The name is used in a similar sense here, except that the Astoria(?) Formation is not The maximum thickness of the Astoria(?) Forma­ known to interfinger with basalt in the Grays River tion is unknown. The Richfield-Weyerhaeuser No. 1 area. The Astoria(?) of the Grays River quadrangle well, located near the mouth of Deep River, pene­ may include strata correlative with both the Nye trated about 2,600 feet of strata considered to be Mudstone and the Astoria Formation of west-central Astoria(?) Formation on the basis of Foraminifera. Oregon (Snavely and others, 1964). This thickness plus the thickness exposed southwest of The predominant lithologic type, seen in outcrops in the well suggest a total of about 3,500 feet in the the valleys of Grays and Deep Rivers, is massive southwest part of the quadrangle. In the central part dark-gray argillaceous siltstone to very fine-grained of the map area the available data suggest that the sandstone. An abundance of mica and very finely Astoria(?) Formation is anomalously thick, but the comminuted carbonaceous debris distinguishes the for­ probability of structural repetition precludes determi­ mation. Glauconite occurs commonly as scattered nation of the actual thickness. In the southeastern grains or, rarely, concentrated in beds. Typical out­ part of the quadrangle the thickness ranges from less crops show no bedding, and excavation of relatively than 500 feet near the eastern edge of the map area to unweathered outcrops reveals that nearly all deposi­ approximately 2,000 feet in the exposures north of tional structure has been destroyed, presumably by Dahlia. The eastward thinning in this area may result burrowing organisms. Locally a few short wisps of the from unconformable relations at the contacts. original bedding have been preserved. Calcareous con­ Mollusks, common in the Astoria(?) Formation ex­ cretions occur in places. cept in the interbedded sandstone and siltstone Massive tuffaceous siltstone, similar to Lincoln Creek mapped west of Deep River, indicate an early to siltstones, crops out in a few places. Molluscan and middle Miocene age. Foraminifera are ubiquitous in foraminiferal assemblages, as well as stratigraphic as­ the fine-grained rocks and are referred to the Episto­ sociation with typical Astoria(?) carbonaceous and minella parva Zone (Rau, 1958) of early to middle micaceous siltstone or sandstone, indicate that the tuf­ Miocene age (Saucesian and in part Relizian Stages of faceous siltstone is part of the Astoria(?) Formation. Kleinpell, 1938). 3

• BASALT FLOWS AND INTRUSIVE ROCKS ALLUVIUM Basalt flows, approximately 500 feet thick, rest with Recent alluvial deposits consisting of sand, silt, and probable unconformity on the Astoria(?) Formation in gravel derived from local sources fill the major stream the southern part of the quadrangle. The flows are valleys. In the valleys of Salmon Creek and the Na­ divided into t,,;o units on the basis of lithology, chem­ selle River some alluvium, possibly as old as Pleisto­ istry, and fabric. cene, and deposits produced by mass movement on valley walls are mapped with the alluvium. Basalt exposed along the Columbia River in the

southeastern part of the quadrangle at Three Tree LANDSLIDE DEBRIS Point and eastward consists largely of massive basalt Mass movement, ranging from surface creep to but also contains some flow breccia and pillow lava. landslides covering areas as wide as half a mile, is Some intrusive rock may be included with the unit in ubiquitous. Only the largest landslides, easily recog­ its westernmost exposures. The basalt is black and nizable on aerial photographs, are shown on the map. aphanitic; it is chemically similar to the lower unit of

Miocene volcanic rocks of the central Oregon Coast INTRUSIVE ROCKS Range (Snavely and others, 1965, p. 107) and to the Intrusive rocks ranging from basalt dikes a few feet Yakima Basalt of the Columbia Plateau (Waters, 1961, wide to large gabbroic intrusives are abundant in the p. 593). northern third of the quadrangle. Along the Columbia River between Altoona and Jim Many of the smaller intrusives in this part of the Crow Point the basalt consists predominantly of flow area consist of porphyritic basalt that is similar in breccia; only small amounts of pillow lava and mas­ petrography to the porphyritic basalt flows of unit B. sive basalt are present. The basalt is fresh and black The larger intrusive bodies are medium grained; and contains scattered plagioclase phenocrysts as large augite and plagioclase crystals are nearly half a centi­ as half an inch in diameter in an aphanitic ground­ meter, and locally as large as a centimeter, in diame­ mass. It is chemically similar to the upper unit of ter. A late Eocene age is inferred from the petro­ Miocene volcanic rocks of the central Oregon Coast graphic similarity of the smaller intrusives to flows of Range (Snavely and others, 1965, p. 107) and to the unit B, from their close association in space, and from late Yakima type of the Columbia River Group of the the absence of these distinctive lithologic types in Columbia Plateau (Waters, 1961, p. 594). Some of the rocks intruding strata known to be younger than the basaltic breccia mapped with the unit may be shallow volcanic rocks of unit B. intrusive rock closely associated with the flows. All intrusive rocks in the southern two-thirds of the STRUCTURAL GEOLOGY quadrangle and the intrusive in secs. 14 and 23, T. 11 Details of the geologic structure are difficult to as­ N., R. 9 W., at the western edge of the quadrangle, are certain because of poor exposures, the limited variety lithologically like the flows exposed along the bank of rock types, the massive character of much of the of the Columbia River. The two distinctive chemical rock sequence, and the scarcity of distinctive marker types recognized in the extrusive rocks are also found beds. Anomalous attitudes, which are not uncommon, among the intrusives. The intrusive rocks chemically may well be the result of landslides or slumping similar to the basalt of Altoona contain similar and rather than of tectonic deformation. distinctive scattered large plagioclase phenocrysts. The Generally, the rocks decrease in age southward rest of the intrusives are aphanitic to very fine grained. along the southern flank of a large northwest-trending A third chemical type is represented by the sill between anticline that has its crest in the higher country near Salmon and Sisson Creeks in the southwestern part of the north edge of the quadrangle. The complementary the quadrangle and by the intrusive in secs. 14 and synclinal trough underlies the Columbia River south 23, T. 11 N., R. 9 W., approximately 6 miles to the of the mapped area. A series of lesGer folds and faults north, which is part of a thick sill exposed west of the is superimposed on this broad structure. map area. A structurally complex syncline strikes northwest in The basalts of Three Tree Point and Altoona rest the west-central part of the map area and is part of a on the Astoria(?) Formation of early to middle Mio­ group of northwest-striking folds and faults that are cene age (Saucesian to Relizian Stages of Kleinpell, strongly defined west of the map area. In the south­ 1938). In the central part of the Oregon Coast Range east quarter of the quadrangle, upper Eocene and the two volcanic units, chemically similar to the two Oligocene rocks form a broad, nearly homoclinal belt units of the Grays River area, are regarded as middle of northwest-striking strata unconformably ovel'lapped Miocene in age (Snavely and others, 1965, p. 111, 112). on the south by the east-west-trending rocks of the An age of middle Miocene or younger is inferred for Astoria(?) Formation. The northwest structural trend the basalts of Three Tree Point and Altoona and for is emphasized by high-angle faults that form the the associated basaltic intrusive rocks. western boundaries of the two large blocks composed of the Crescent Formation and unit A in the northeast­ OLDER ALLUVIUM ern and northwestern parts of the quadrangle. The Deposits of sand, silt, and gravel derived from the northeastern block is bounded on its southwest side by local sedimentary and volcanic rocks rest unconforma­ a pronounced scarp that reflects one of these faults. bly on Tertiary rocks along the edges of the Grays North- to northwest-trending dikes in the southeast­ River valley. The maximum thickness is about 100 ern part of the quadrangle may lie along a southern feet. The broad flat upper surfaces of these deposits of extension of this fault, or a southern extension may older alluvium form terraces that are easily recogniz­ exist unrecognized in the volcanic rocks of unit B in able on aerial photographs. the east-central part of the quadrangle. 4

• Northeast structural trends are less pronounced. The ROAD METAL more important of these trends are defined by the Basalt from the volcanic and intrusive rocks is southern boundaries of the two large masses of Cres­ quarried from numerous small pits for use as road cent Formation and unit A, by northeast-striking metal in the extensive network of logging roads. rocks of unit B in the north-central part of the quad­ rangle, and by the strike of the Astoria(?) Formation SAND in the Grays River valley. The faults bounding the Medium- to coarse-grained sand that could be used Astoria (?) Formation are conjectural, and were drawn in construction has been dredged from the bed of the to account for the thick northeast-striking mass of the Columbia River near its north bank at Dahlia and Astoria (?), which truncates the northwest-striking Brookfield, in the south-central part of the quadran­ Lincoln Creek Formation in the south-central part of gle. Except for scattered pumice pebbles, the sand is the quadrangle, and to account for the absence of the well sorted. Lincoln Creek Formation between the Astoria(?) and unit B in the west-central part of the quadrangle. An 0IL AND GAS additional fault within the Astoria(?) west of Deep Sedimentary rocks of the Grays River quadrangle River accounts for opposing northeast and northwest contain organic material and could be source beds for structural trends within the formation. oil or gas. The stratigraphic succession consists pre­ dominantly of volcanic rocks and extremely fine ECONOMIC GEOLOGY grained sedimentary rocks that are too impermeable FERRUGINOUS BAUXITE to be suitable reservoir rocks for oil or gas. Middle Fcrruginous bauxite, a potential ore of aluminum, Eocene sandstones contain a large amount of clay develops as a weathering product of some basaltic matrix and can be expected to have low porosity. Unit rocks. However, no ferruginous bauxite is known to B and Astoria(?) strata, however, include some rela­ exist in the Grays River quadrangle, although intru­ tively clean sandstones that may be potential petro­ sive basalt about half a mile west of the crest of Jim leum reservoirs. Crow Hill shows unusually deep weathering. The rock An exploratory well, the Richfield-Weyerhaeuser is altered almost completely to a soft reddish-brown No. 1, was drilled near the mouth of Deep River in powdery deposit, in which, according to an X-ray the southwestern part of the quadrangle. It was diffractogram, gibbsite is probably the major crystal­ started in the Astoria (?) Formation below the upper line constituent. The following chemical analyses indi­ unit mapped west of Deep River and bottomed in cate that some decrease in silica content and accompa­ volcanic rocks of unit B at a total depth of 9,110 feet. nying increases in alumina, iron oxide, and titania The well did not intersect any oil-producing strata. have occurred. Except for the single thick sandstone mapped in Fresh Weathered unit B in the Grays River valley, sandstones of unit B basalt© basalt® are too thin and sporadically distributed to form siz­ (percent) (percent) able reservoirs. Northeast of the map area, thick upper Eocene sandstones of the Skookumchuck For­ Si02 ...... 55.2 39.6 mation (Pease and Hoover, 1957; Snavely and others, ALO, ...... 14.4 17.6 1958) are a near-shore facies of the deeper marine Fe20a ...... 1.1 13.3 strata of unit B in the Grays River quadrangle. Areas FeO ...... 9.9 3.6 to the east offer more likely possibilities for the oc­ MgO ...... 3.7 2.5 currence of structural or stratigraphic traps in upper CaO ...... 6.9 3.5 Eocene strata than does the Grays River quadrangle. Na20 ...... 3.2 .90 K20 ...... 1.3 .27 The better sorted sandstones of the Astoria (?) For­ mation seem especially favorable as potential petro­ H20- ...... 34 7.3 leum reservoirs, because they are interbedded with H20+ ...... 1.0 6.3 fine-grained strata that are rich in organic material Ti02 ...... 1.8 3.6 and can serve both as source rocks and as barriers to P20, ...... ·. · .. · .35 .66 MnO ...... 20 .23 oil or gas migration. The clean crossbedded sandstones of the Astoria (?) in the southeastern part of the co, ...... 52 .06 quadrangle are probably a shallow-water facies of limited areal extent. Their distribution to the east is 99.91 99.42 unkno,vn; they probably do not occur farther west, (D SE%SE% sec. 7, T. 9 N., R. 7 W. where the basin presumably was deeper. ® SE%NW% sec. 17, T. 9 N., R. 7 W. The Astoria (?) sandstones in the separately mapped Rapid rock analyses by P. Elmore, S. Botts, L. Artis, unit west of Deep River are interbedded with silt­ and H. Smith (U.S. Geological Survey). stones that, at least in part, contain Foraminifera indicative of bathyal deposition (W. W. Rau, written An average of analyses of ferruginous bauxite communication, 1966). The only mollusks known in from Cowlitz County, Wash. (Livingston, 1966, p. 88, the sequence are mud pectens, which, occurring alone, Table 13), shows Al20,, 38 percent; Fe20a, 27 percent; also suggest deposition at bathyal depths (W. 0. Addi­ Ti02, 4 percent; and Si02, 6 percent. These analyses cott, oral communication, 1966). The possibility exists indicate that typical western Washington ferruginous that these are deep-water sandstones, perhaps depos­ bauxite deposits are higher in Al20a, Fe20a, and Ti02 ited by turbidity currents. If so, they may occur in the and much lower in Si02 than the weathered basalt from present offshore area and could be potential targets in the Grays River quadrangle, offshore petroleum exploration. 5 REFERENCES CITED

BEIKMAN, H. M.; RAU, w. W.; and WAGNER, H. c., RAU, W. W., 1966, Stratigraphy and Foraminifera of 1967, The Lincoln Creek Formation, Grays Harbor the Satsop River area, southern Olympic Penin­ basin, southwestern Washington: U.S. Geol. Sur­ sula, Washington: Washington Div. Mines and vey Bull. 1244-I, 14 p. Geology Bull. 53, 66 p. CoPE, E. D., 1880, Corrections of the geological maps SCHENCK, H. G., and KLEINPELL, R. M., 1936, Refugian of Oregon: Am. Naturalist, v. 14, p. 457-458. Stage of Pacific coast Tertiary: Am. Assoc. Petro­ DURHAM, J. W., 1944, Megafaunal zones of the Oligo­ leum Geologists Bull., v. 20, no. 2, p. 215-225. cene of northwestern Washington: Univ. of Cali­ SNAVELY, P. D., JR., and BALDWIN, E. M., 1948, Siletz fornia Pubs., Dept. Geol. Sciences Bull., v. 27, no. River volcanic series, northwestern Oregon: Am. 5, p. 101-211. Assoc. Petroleum Geologists Bull., v. 32, no. 5, p. GOWER, H. D., 1960, Geology of the Pysht quadrangle, 805-812. Washington: U.S. Geol. Survey Geol. Quad. Map GQ-129, scale 1: 62,500. SNAVELY, P. D., JR.; BROWN, R. D.; ROBERTS, A. E.; and RAU, W. W., 1958, Geology and coal resources of Gm,VER, H. D., and PEASE, M. H., JR., 1965, Geology of the Centralia-Chehalis district, Washington: U.S. the Montesano quadrangle, Washington: U.S. Geol. Survey Bull. 1053, 159 p. Geol. Survey Geol. Quad. Map GQ-374, scale 1: 62,500. SNAVELY, P. D., JR.; RAU, W. W.; and WAGNER, H. C., HENRIKSEN, D. A., 1956, Eocene stratigraphy of the 1964, Miocene stratigraphy of the Yaquina Bay lower Cowlitz River-eastern Willapa Hills area, area, Newport, Oregon: Oregon Dept. Geology southwestern Washington: Washington Div. Mines and Minernl Industries, Ore Bin, v. 26, no. 8, p. and Geology Bull. 43, 122 p. 133-151. KLEINPELL, R. M., 1938, Miocene stratigraphy of Cali­ SNAVELY, P. D., JR.; WAGNER, H. C.; and MACLEOD, N. fornia: Am. Assoc. Petroleum Geologists, Tulsa, S., 1965, Preliminary data on compositional varia­ Okla., 450 p. tions of Tertiary volcanic rocks in the central part LIVINGSTON, V. E., JR., 1966, Geology and mineral of the Oregon Coast Range: Oregon Dept. Geology resources of the Kelso-Cathlamet area, Cowlitz and Mineral Industries, Ore Bin, v. 27, no. 6, p. and Wahkiakum Counties, Washington: Washing­ 101-117. ton Div. Mines and Geology, Bull. 54, 110 p. WAGNER, H. C., in press, Geology of the Raymond MALLORY, V. S., 1959, Lower Tertiary biostratigraphy quadrangle, Grays Harbor County, Washington. of the California coast ranges: Am. Assoc. Petro­ WATERS, A. C., 1961, Stratigraphic and lithologic vari­ leum Geologists, Tulsa, Okla., 416 p. ations in the Columbia River basalt: Am. Jour. PEASE, M. H., JR., and HOOVER, LINN, 1957, Geology of Sci., v. 259, no. 8, p. 583-611. the Doty-Minot Peak area, Washington: U.S. WEAVER, C. E., 1937, Tertiary stratigraphy of western Geol. Survey Oil and Gas Inv. Map OM-188, scale Washington and northwestern Oregon: Univ. of 1: 62,500. Washington Pubs. in Geology, v. 4, 266 p. RAu, W. W., 1958, Stratigraphy and foraminiferal zo­ WEAVER, C. E., and others, 1944, Correlation of the nation in some of the Tertiary rocks of southwest­ marine Cenozoic formations of western North ern Washington: U.S. Geol. Survey Oil and Gas America [Chart 11]: Geol. Soc. America Bull., v. Inv. Chart OC-57. 55, no. 5, p. 569-598.

6

• WASHIN GTON DEPA RTMENT OF NAT URAL RESO URCES PREPAR ED COOPERA TIVELY BY THE GEOLOGIC MAP DIVISION OF MINES AND GEOLOGY U.S. GEOLOGICA L SURVEY GM -4

E XPLA N ATI ON

' Q ls >­ er Landslide debris Alluvium z~ Gro t e/, sr1;1d mu! .,ii! er w J oa ~ :, .:'.; 0 I{ Older al luvium ii' ' ~ (jm ,·61, ,wml, 11111/ silt ' ~>, ' T.·I T I_L.,.,,,.,., ~ Tba

Tbt

Basalt flows and in trusive rocks Tba, ///IS(J// of A lloo11a: b,u;u ll /1rcai

AHloria(?) Formation Tasu, u1111(t111eil air(/; sills/0>1 ,:, ti1ffw·wu,;, wilh inlel"li edr/erl vuryjh1e lo 1, cry eour.,1.• 11n1inerl xamfa/01,e ' Tbi Tas, 1,d/t,;trrn e to 1ir r11fine 01·,,in P. d M11ulstmw

>­ Lineoln Creek Formation er Si/t.~l011 e, f11j](weo11A; mi1101· ylr,11co11itfr 11ml /;(IS(riri,· M;r,r{.,/vno. B11.s (' <1/ IIJJJWI" y/,,u- "' >­er 1"/Jtd!i,· ""'/ 1; ,.nd11 z o111, in,Jicolerl l•!I !/!Ji" w (111d il(1 sli e1< >-- ~ ~ J Intrusive rocks Unit B Ba~ult (11/fl fl<(h/;nJ Tb . .si/1,;fom ,, /1{/}(1<·co,,,.,: mi11or i;(11u/i;/1JII!' Tbs, eoudsl(Jlle,fl'iul,le, nw.~i;i11/i Tbv. voln111/c rm:k.~ : a,11wve 1rn luff. bo.i;o/1 .flows D Unit A Si/1.~tmie; )"eldsp(lf/tic (LJUl wlcrmic wada;

Crescent Formation Pillow {1<1salt: mhwr siltdmw , so11d1

' Contact App1·0 ..-i:nmtely located: :;/wl"I. do.~lr ed whe re inferred: iloUed ,11he,·e ,·ow:ea/ed

u -- D - -?- - ?- --

Faul t Tbl Appn,.i:i,m11tcl11 lorMe1l: ~h,!rl d/1 ..ShMl where ·i ufe 1·i·ed; doUe,l w/1.P/'I' ,·on,-,,,,/~d. 1111 e r i t' rl 11 ·h.e i·p 1,rolia/J/e or lmput/,eti1.:ul: U . nvthrown .~idc. D . du 1v1d hruwn .~ide

Tas ------'!-- -?- ·· ----+-'!---'/-··' . . Anticline Synelil1e Folds Slwwhi!J lruce uf u:dnl J)ltm,: rend di 1·ection of p/ 1~11ge Lonr1 ,[ashed whe re 11J11n·o:rinrn(e/'/f lucalel/, .

-I­ G s '' "' Incl ined Overturned Vertical Horizontal Qo Strika and diJ) or hods Ge11rndized wlr e1·e 1,0 ·;uim.erh:11l vo/1w f~ yiuen THU T ic

Exploratory test well Riclifir!d Oil C(1r 11. Wcyel'h.fl1•u .~r·r No. I ,, ,. S W }'j Scr·. SI, T. 1/1 N., R . J$ 1V.

H A ..

. ,p

./ '\ H tt • '

11111.!.. • ~ ' " ,, '" ---- I - "' • "N, Base by U.S. Geologica l Survey, 1955 SCALE 1 62 500 Geology mapped 1963-1 966

0 2 3 MILES .5 0 ' 3 KILOMETERS CONTOUR INTERVAL 50 FEET DATUM IS M EA N SEA LEV EL DEPTH CURVES IN FEET-CO LUMBIA RIVER DATUM v.=,~1 L..--.-,--~ ,~, .,.., "' ~. QUADRANGL E LOCATION

A' Ta Ti 3000' Tc 2000' g /--Tc':;

SEA LEVEL 1000'

Tbs - 2000' 3000' 4000' 5000'

6000' 7000' 8000' 8000' T b, 9000' 9 11 0' T.D. St ructure schematk In part 9ooo• 10000' ~------_,_ 10000' GEOLOGIC SECTION ALONG LINE A-A'

B B' 2000' r--- --~ ~ ~ T_, _ _ _ _ _ 2000 ' 1000' 1000'

SEA LEVEL SEA LEV EL 1000' 1000' 2000' 2000'

3000' 3000' 4000' Structure sche matic in part 4000' 5000' ~------.1... 5000' GEOLOGIC SECTION ALONG LI NE 8-B'

C C' 3000' 3000' 2000' Ti Tb, Ta Tc 2000' Tic ~ .. ., ~ Tb Tc 1000' :;; 'fas Tic 1 1000' SEA LEVEL __j_df C°' ~ -. :..- --:: :_,_ -'._f- · - S EA LEV EL 1000' - ,I- 1000' 2000' 2000' ---" - 3000' 4000' Structure schematic in part 4000' 5000' ~ ------~------.L 5000'

GEOLOGIC SECT ION ALONG L INE C-C'

For sale by Department of Natural Re sources. Olym pia, Washington Pri ce. $1.00 GEOLOGIC MAP GM-4 GEOLOGY OF THE GRAYS RIVER QUADRANGLE, WAHKIAKUM AND PACIFIC COUNTIES, WASHINGTON By E dward W. Wolfe and Edwin H . McKee U.S. Geologic~ ! S urvey 1968