Information about fossils collected by U.S. Geological Survey, State of Alaska, academic, and industry geologists that have been reported in literature or archived in reports from the former U.S. Geological Survey Branch of Paleontology and Stratigraphy are compiled on a plate and table in this report to provide comprehensive paleontologic age data for the Taylor Mountains quadrangle area in southwestern Alaska. The reports used to compile the table in this report were submitted by recognized paleontologic experts. Some of the information is derived from reports that date back almost 100 years. Many of the data are available in more detail in the Alaska Paleontological Database (http://www.alaskafossil.org/). The 287 entries in this table are shown on the accompanying plate, on which symbols representing the entries are color-coded by geologic age. This report represents the most comprehensive and most recently updated compilation of paleontologic data for this area.

This report contains information about the composition of interstitial porewater and solids from water saturated, metal contaminated levee banks at the river's edge and marshes in the lower Coeur d'Alene River valley.Data include pH, alkalinity, and concentrations of sulfate and metals (arsenic [As], cadmium [Cd], copper [Cu], iron [Fe], mercury [Hg], manganese [Mn], lead [Pb], antimony [Sb], and zinc [Zn]) in porewater and sulfur (S), carbon (C), and metal contents of associated solids.The results indicate that the pH of the porewater in all of the sediments is less than the pH of the Coeur d'Alene River.Dissolved concentrations of Mn and Fe are elevated in all of the porewater and levels of sulfate in porewater are below detection limits in almost all marsh sediments and in levee banks at the 2 sites furthest downstream.These observations suggest that levee bank and marsh sediments are suboxic or anoxic below the surface.Concentrations of dissolved Cd are greater in the Coeur d'Alene River than in porewater, while concentrations of As are greater in the porewater relative to the Coeur d'Alene River.Some concentrations of Cu, Pb, Sb, and Zn in porewater are lower, while others are higher, than dissolved concentrations in the Coeur d'Alene River.In addition, leaching experiments (i.e., Standard Elutriate Tests [SET]) were done in the laboratory to evaluate potential water quality impacts resulting from the addition of oxygen and water to these sediments.The intent of the experiments was to simulate how metal concentrations in water may be affected during dredging of contaminated sediments in the lower Coeur d'Alene River valley.The results indicate that there are releases of protons, sulfate, As, Mn, Pb, Sb, and Zn from the majority of levee bank and marsh sediments during leaching by Coeur d'Alene River water.At a water to sediment ratio of 4 to 1, most values of pH and dissolved concentrations of Cd, Fe, Pb, and Zn in the leaching solutions exceed the freshwater aquatic life standards for water of a hardness of 100 mg CaCOa/L.This work was funded by the U.S. EPA and was done to support their Remedial Investigation/Feasibility Study of the Coeur d'Alene and Spokane River basins.Development of effective remediation plans for the Coeur d'Alene and Spokane River basins requires an understanding of the distribution and composition of aqueous and solid phase materials throughout the system and, ultimately, the processes that result in the mobilization, transport, and fate of metals associated with these materials.Towards that end, this report provides information on the composition of porewaters and associated solid phases at a dozen sites within the lower Coeur d'Alene River valley.Sites were chosen to represent two types of environments -water saturated levee banks near the edge of the Coeur d'Alene River and backlevee marshes.In addition, results from a set of leaching experiments on the solid phases and associated porewater are presented.These experiments were done to provide information on potential metal release or uptake by sediments during dredging operations. STUDY AREAA total of 12 sites in the lake-backflooded reach of the lower Coeur d'Alene River valley between Cataldo and Harrison were selected for sampling of porewaters from saturated soils during drawdown of Lake Coeur d'Alene in the fall.Sampling was undertaken during the week of November 2-9, 1998.During this time, the water level in Lake Coeur d'Alene fell about 0.1 m and was about 1 m below its summer pool level.Porewaters were sampled from levee bank sediments at the edge of the Coeur d'Alene River and from back-levee marsh environments.Porewater was sampled at 2-4 shallow (< 50 cm) depth horizons within the historic, metalenriched sediments that have been deposited since mining began.The locations of the sites are shown in Figure 1 and summarized in Table 1.The stratigraphy of the two environments is distinctly different and results from variations in their depositional settings.The stratigraphy of the levee banks at the river's edge is characterized by alternating thin (1-3 cm) layers of sand and silt, with rare, thin plant-debris-rich horizons.Typically, sands coarser than very fine grained (grains coarser than 0.125 mm) in the upper 20-40 cm of the section have irregular red-brown iron oxide stains, whereas interbedded silts and very fine sands or more deeply buried fine sands and coarser are gray or green-gray in color.Where the sample site is situated on the inside of a gently curving river segment (sites 98R1, 98K1 arid 98M1), the thickness of the historic, metal-enriched sediments greatly exceeds 50 cm.Where the sample site is situated on a straight section or on the outside of a gently curving river segment (sites 98C1, 98T1), the historic, metal-enriched sediments are a relatively thin veneer (14-34 cm) over lithologically similar, metal-poor pre-mining sediments.The stratigraphy of the marsh environment is much more dominated by plant materials.The upper horizon of historic, metal-enriched sediment ranges from 40 to >70 cm thick and is typically subdivided into an upper horizon rich in black composting plant material (+/-20 cm), and a lower horizon of banded gray silt with pervasive fibrous root material and occasional organic-rich seams.The pre-mining section immediately below the historic sediments is characterized by silt-poor peat.The stratigraphy of the cores collected from the individual sites is given in Table 2. Site 98C1 Cataldo-levee bank (Cataldo quadrangle)This sample site is located on the north side of the river on the river's edge bench about 5 m toward the river from the 2.5 m cutbank and about 12m downstream from the pier at the Cataldo boat landing.Immediately shoreward of the bank is an extensive area of historic sandy dredge spoils dredged From the channel from 1932 to the 1960's, overlain by and partly incorporated into the 1-90 highway embankment.The river's edge bench is characterized by Location description Cataldo-levee bank Cataldo-levee bank Cataldo-levee bank Cataldo-

This report contains information about collecting, handling, and analyzing waters draining from adits and seeping from beneath tailings piles in the Coeur d'Alene mining district during August 1996, November 1996, and June 1997. Data include temperature, pH, conductivity, dissolved oxygen, alkalinity, flow, and total acid soluble and dissolved (<0.45 \im) major and trace ion concentrations for 11 adits and 5 tailings deposits. Interpretations of these data will be discussed in other publications.

TectonicsVolume 12, Issue 4 p. 1076-1081 Free Access Comment [on "Mid-Cretaceous extensional fragmentation of a Jurassic-Early Cretaceous compressional orogen, Alaska" by E. L. Miller and T. L. Hudson] Alison B. Till, Alison B. TillSearch for more papers by this authorS. E. Box, S. E. BoxSearch for more papers by this authorS. M. Roeske, S. M. RoeskeSearch for more papers by this authorW. W. Patton Jr., W. W. Patton Jr.Search for more papers by this author Alison B. Till, Alison B. TillSearch for more papers by this authorS. E. Box, S. E. BoxSearch for more papers by this authorS. M. Roeske, S. M. RoeskeSearch for more papers by this authorW. W. Patton Jr., W. W. Patton Jr.Search for more papers by this author First published: August 1993 https://doi.org/10.1029/93TC00671Citations: 12AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onEmailFacebookTwitterLinkedInRedditWechat References Arth, J. G., R. E. Criss, C. C. Zmuda, N. K. Foley, W. W. Patton Jr., T. P. Miller, Remarkable isotopic and trace element trends in potassic through sodic Cretaceous plutons of the Yukon-Koyukuk basin, Alaska, and the nature of the lithosphere beneath the Koyukuk terrane, J. Geophys. Res., 94, 15957–15968, 1989a. 10.1029/JB094iB11p15957 ADSWeb of Science®Google Scholar Arth, J. G., C.C . Zmuda, N. K. Foley, R. E. Criss, W. W. Patton Jr., T. P. Miller, Isotopic and trace element variations in the Ruby batholith, Alaska, and the nature of the deep crust beneath the Ruby and Angayucham terranes, J. Geophys. Res., 94, 15941–15956, 1989b. 10.1029/JB094iB11p15941 ADSWeb of Science®Google Scholar Box, S. E., Evidence for basin-margin right-slip faulting during Kuskokwim group deposition, southwestern Alaska, Geol. Soc. Am. Abstr. Programs, 24, 8, 1992. Google Scholar Box, S. E., W. W. Patton Jr., Igneous history of the Koyukuk terrane, western Alaska: Constraints on the origin, evolution, and ultimate collision of an accreted island arc terrane, J. Geophys. Res., 94, 15843–15867, 1989. 10.1029/JB094iB11p15843 ADSWeb of Science®Google Scholar Box, S. E., W. W. Patton Jr., C. 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M., Depositional history and seismic stratigraphy of Lower Cretaceous rocks in the National Petroleum Reserve in Alaska and adjacent areas, Geology and Exploration of the National Petroleum Reserve in Alaska, 1974 to 1982 G. Gryc, U.S. Geol. Surv. Prof. Pap., 1399, 593–621, 1988. Google Scholar Molenaar, C. M., R. M. Egbert, L. F. Krystinik, Depositional facies, petrography, and reservoir potential of the Fortress Mountain formation (Lower Cretaceous), central North Slope, Alaska, Geology and Exploration of the National Petroleum Reserve in Alaska, 1974 to 1982 G. Gryc, U.S. Geol. Surv. Prof. Pap., 1399, 257–280, 1988. Google Scholar Moore, T. E., W. K. Wallace, K. J. Bird, S. M. Karl, C. G. Mull, J. T. Dillon, Stratigraphy, structure, and geologic synthesis of northen AlaskaU.S. Geol. Surv. Open File Rep. 92-330, 183, 1992. Google Scholar Mull, C. 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Programs, 23, 87, 1991. Google Scholar Patrick, B. E., W. S. Dinklage, A. B. Till, An inverted metamorphic field gradient in the central Brooks Range, Alaska, and implications for exhumation of high-pressure/low-temperature metamorphic rocks, Lithos, 1993. Web of Science®Google Scholar Patton Jr., W. W., Reconnaissance geology of the northern Yukon-Koyukuk province, AlaskaU.S. Geol. Surv. Prof. Pap., 794-A, 77, 1973. Google Scholar Patton Jr., W. W., S. E. Box, Tectonic setting of the Yukon-Koyukuk basin and its borderlands, Alaska, J. Geophys. Res., 94, 15807–15820, 1989. 10.1029/JB094iB11p15807 ADSWeb of Science®Google Scholar Patton Jr., W. W., andT. P. Miller, Regional geologic map of the Hughes quadrangle, Alaska, scale1∶250,000,U.S. Geol. Surv. Misc. Geol. Invest. Map, 1-459,1966. Google Scholar Patton Jr., W. W., J. M. Murphy, L. E. Burns, S. W. Nelson, S. E. 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Hanks, J. F. Rogers, The southern Kahiltna terrane: implications for the tectonic evolution of southwestern Alaska, Geol. Soc. Am. Bull., 101, 1389–1407, 1989. 10.1130/0016-7606(1989)101<1389:TSKTIF>2.3.CO;2 ADSWeb of Science®Google Scholar Wirth, K. R., D. J. Harding, A. E. Blythe, J. M. Bird, 1986, Brooks Range ophiolite crystallization ages from 40Ar/39Ar data, Geol. Soc. Am. Abstr. Programs, 18, 792, 1986. Google Scholar Citing Literature Volume12, Issue4August 1993Pages 1076-1081 ReferencesRelatedInformation

Upper Cretaceous rocks of the Kuskokwim Group are exposed in a large region of southwestern Alaska and are mainly composed of deformed turbidite deposits that contain few fossils other than inoceramid bivalves. This paper documents the taxonomy of the inoceramids in the Kuskokwim Group, develops an inoceramid biostratigraphy based on known ranges in other regions, and analyzes biogeographic patterns, paleoecology, and depositional history of the Kuskokwim Group.Most of the inoceramid bivalves present in the Kuskokwim Group are of Cenomanian and Turonian age, and an assemblage of species typical of late Turonian age rocks is particularly well developed. Only two localities appear to be as young as Santonian age. The following 16 species or subspecies are discussed and illustrated in detail:Birostrina tamuraiMatsumoto and Noda,Inoceramus virgatusSchlüter,I. pennatulusPergament,I. pictus minusMatsumoto,I.cf.I. yabeiNagao and Matsumoto,I.? sp. aff.I. costatusNagao and Matsumoto,I. hobetsensisNagao and Matsumoto,I. longealatusTröger,I. frechiFlegel,I. waltersdorfensis waltersdorfensisAndert,I.cf.I. waltersdorfensis hannovrensisHeinz,I. kuskokwimensisn. sp.,Mytiloidescf.M. opalensis(Böse),M. teraokai(Matsumoto and Noda),M.cf.M. incertus(Jimbo), andSphenoceramus naumanni(Yokoyama). In addition, a specimen with affinities toMytiloides striatoconcentricus carpathicus(Simionescu) and a specimen that may belong to theI. (Cremnoceramus?) rotundatus–I.(C.)erectuslineage are illustrated.Most of the taxa present in the Kuskokwim region are found in other regions of the North Pacific, particularly Japan and eastern Siberia, or are found throughout the Northern Hemisphere. Only one species,I. kuskokwimensisn. sp., is new and may be endemic. North Pacific taxa are predominant in the Kuskokwim region, but intervals near the Cenomanian–Turonian Stage boundary and in the upper Turonian contain taxa characteristic of Europe and the Western Interior basin of North America; some of these taxa have not been recorded previously in the North Pacific region. Turonian heteromorph ammonite assemblages associated with inoceramids in the finer grained facies of the Kuskokwim region are similar to those found in coeval rocks of Japan and Germany.The depositional area of the Kuskokwim Group can be broken into two northeast-trending subbasins, the Kuskokwim River subbasin to the northwest and the Mulchatna River subbasin to the southeast, connected by the Nushagak Hills corridor. Within the Kuskokwim River subbasin, deposition apparently started earlier in the north (middle Cenomanian) than in the south (late Cenomanian to early Turonian), and prograding deltaic sedimentation along the western margin also appears to have started earlier in the north. No marine fossils younger than latest Turonian to earliest Coniacian are known from the Kuskokwim River subbasin. The youngest fossils identified are Santonian in age and are from deep-water deposits in the Nushagak Hills corridor. Few fossils are known from the Mulchatna River subbasin and age control is limited.

Research Article| December 01, 1990 Kilbuck terrane: Oldest known rocks in Alaska Stephen E. Box; Stephen E. Box 1U.S. Geological Survey, U.S. Courthouse, Room 656, Spokane, Washington 99201 Search for other works by this author on: GSW Google Scholar Elizabeth J. Moll-Stalcup; Elizabeth J. Moll-Stalcup 2U.S. Geological Survey, 345 Middlefield Road, Menlo Park, California 94025 Search for other works by this author on: GSW Google Scholar Joseph L. Wooden; Joseph L. Wooden 2U.S. Geological Survey, 345 Middlefield Road, Menlo Park, California 94025 Search for other works by this author on: GSW Google Scholar John Y. Bradshaw John Y. Bradshaw 3U.S. Geological Survey, 4200 University Drive, Anchorage, Alaska 99508 Search for other works by this author on: GSW Google Scholar Author and Article Information Stephen E. Box 1U.S. Geological Survey, U.S. Courthouse, Room 656, Spokane, Washington 99201 Elizabeth J. Moll-Stalcup 2U.S. Geological Survey, 345 Middlefield Road, Menlo Park, California 94025 Joseph L. Wooden 2U.S. Geological Survey, 345 Middlefield Road, Menlo Park, California 94025 John Y. Bradshaw 3U.S. Geological Survey, 4200 University Drive, Anchorage, Alaska 99508 Publisher: Geological Society of America First Online: 02 Jun 2017 Online ISSN: 1943-2682 Print ISSN: 0091-7613 Geological Society of America Geology (1990) 18 (12): 1219–1222. https://doi.org/10.1130/0091-7613(1990)018<1219:KTOKRI>2.3.CO;2 Article history First Online: 02 Jun 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn Email Permissions Search Site Citation Stephen E. Box, Elizabeth J. Moll-Stalcup, Joseph L. Wooden, John Y. Bradshaw; Kilbuck terrane: Oldest known rocks in Alaska. Geology 1990;; 18 (12): 1219–1222. doi: https://doi.org/10.1130/0091-7613(1990)018<1219:KTOKRI>2.3.CO;2 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyGeology Search Advanced Search Abstract The Kilbuck terrane in southwestern Alaska is a narrow, thin crustal sliver or flake of amphibolite facies orthogneiss. The igneous protolith of this gneiss was a suite of subduction-related platonic rocks. U-Pb data on zircons from trondhjemitic and granitic samples yield upper-intercept (igneous) ages of 2070 ±16 and 2040 ±74 Ma, respectively. Nd isotope data from these rocks suggest that a diorite-tonalite-trondhjemite suite (εNd [T] = +2.1 to +2.7; T is time of crystallization) evolved from partial melts of depleted mantle with no discernible contamination by older crust, whereas a coeval granitic pluton (εNd [T] = -5.7) contains a significant component derived from Archean crust. Orthogneisses with similar age and Nd isotope characteristics are found in the Idono complex 250 km to the north. Early Proterozoic rocks are unknown elsewhere in Alaska. However, Phanerozoic plutons cutting several "continental" terranes in Alaska (southern Brooks Range and Ruby, Seward, and Yukon-Tanana terranes) have Nd isotope compositions indicative of Early Proterozoic (or older) crustal components that could be correlative with rocks of the Kilbuck terrane. Rocks with similar igneous ages in cratonal North America are rare, and those few that are known have Nd isotope compositions distinct from those of the Kilbuck terrane. Conversely, provinces with Nd model ages off 2.0-2.1 Ga are characterized by extensive 1.8 Ga or younger plutonism, which is unknown in the Kilbuck terrane. At present the case for a North American parentage of the Kilbuck terrane is not compelling. The possibility that the Kilbuck terrane was displaced from provinces off similar age in other cratons (e.g., Australian, Baltic, Guiana, and west African shields), or from the poorly dated Siberian craton, cannot be excluded. First Page Preview Close Modal You do not have access to this content, please speak to your institutional administrator if you feel you should have access.

West-central Alaska includes a broad area that stretches from the Bering and Chukchi seacoasts on the west to the upper Yukon-Tanana Rivers region on the east, and from the Brooks Range on the north to the Yukon-Kuskokwim delta on the south. It covers 275,000 km2, nearly one-fifth of the entire state—and all or parts of 29 1:250,000 scale quadrangles (Fig. 1).

You get a comprehensive overview of the geology, tectonic evolution, and mineral resources of Alaska and adjacent areas of the continental margin. Plates include state-wide maps showing geology, physiography, lithotectonic terranes, metamorphic rocks, igneous rocks, sedimentary basins, isotopic age data, neotectonics, isostatic gravity, magnetics, and metallic mineral deposits. Summaries of bedrock geology and geologic history are given for eleven large regions of Alaska and adjacent offshore areas. Twenty topical chapters synthesize data on metamorphic and igneous rocks; major onshore and offshore sedimentary basins; the paleomagnetics evidence for latitudinal displacements and rotations, glacial history and periglacial phenomena; and the occurrence, evolution, and potential of Alaska's vast resources of petroleum, coal, and metallic minerals. A summary chapter provides an overview and presents a possible model for Alaska's Phanerozoic evolution. The Geology of Alaska is the largest publication produced in the Decade of North American Geology program, a fitting tribute to this magnificent area.