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the publlc as a contact polnt for obtaining information about the activities and pducts of the Survey, as over-the-counter sources of map and report products of the U.S. Geological Survey, and they provide referral service for individuals seeking technical information. h fiscal year 1981 the Anchorage PIO, staffed by twb full-time and two part-time employees, replied to more than 30,000 information requests reaelved in person, by telephone, and by maU. More than 112,000 topographic and thermetic maps and 2,000 publfcationa were sold. Some 1,100 people used the reference library, and more than 800 patrons were assisted in consulting the files of O.S. Geological Survey Open- File Reports on Alaska. - (Ffgure 5 shows study areas discussed) The m t Cowbmerate fn tbe weatemmost ~rooke Ala* h e Upper Devonian end Lower Missfasippian(?) Kanayut Conglomerate is an allochthonous coarse- grained elastic unit that forms a distinctive and mappable stratigraphic unit in the central and eastern Brooks Range (Bowsher and Dutm, 1957; Porter, 1966). It Is as thlck as 3,000 m and has been divided, in ascending order, into the Bar Peak Member, Shainin Lake Member, and Stwer Member. The Ear Peak and Stuver members typically contain multiple fining- and thinning-upward cycles that appear to be characteristic of depositlon by meandering streams, whereas the Shainin Lake Member typically contains more massive outcrops of conglomerate and sandstone that appear to be characteristic of deposition by braided streams (NUsen and others, 1980, 1Q8lb, 19821. Conglomerate of the Kanayut Is composed of chert, quartzite, and quartz olasts, and the sandstone is typically ortho- quartzitio in composition. me Kanayut records out- building of a ma'or dominantly fluvial delta to Me south and west ? Nilsen and others, 198la). It has generally been considered to pinch out laterally to the south and west into age-equivalent units. Herein, and in a recently released Open-File Report (Nilsen and Moore, 19621, we document its presence in Paleozoic stratigraphic sequences in the *Husky Mountainsn and the Mulgrave X U at the westernmost margin of the Broaks Range (area 6, fig. 5; Pig. 6). In the central and eastern Brooks Range (between about long 1~6~-147~) the Kanayut Conglomerate rests conformably on the marine Upper Devonian FlgUm!! ~.-AII~E~ fn northern Alaska dimused In this Ellersieck and 8 (p. 16-17); 3, Galloway volume. A listing of authorshi , applicable f l and Koster, figures lu and 11, table 2 (p. 20-21); 4, tabla, and article pagination P in parenth-~~~?~ Hamilton and Van Etten, figure 12 (p. 21-2311 5, to the numbered areas follows. 1, Dutro and others, Lachenbruch and others (p. 19-20); 6, Nilsen and front-cover photograph, flgure 9 (p. 17-19); 2, Moore, figures 6 and 7 (p. 12-16).
Noatak Sandstom and is overlaln conformably by the marine Lower Mississippian Kayak Shale (Brow6 and Pessel, 1977; Mayfield and Taillew, 1978; Brosgdand others, 1979a, b; Nelson and Grybeck, 1980). Where the Noatak Sandstone, previously mapped as the rnmlne basal sandstone member of the Kanayut Con- glomerate, is missing, the Kanayut rests directly on the marine Upper Devonian Hunt Fork Shale. The Kanayut has been mapped together with the Noatak Sandstone as an undivided Devonian and Mlsslssippian unit as far west as the Misheguk Mountain quadrangle and the south haLf of the National Petroleum Reserve In Alaska (Mayfleld and others, 1978, 1982; ELlersieck md others, 1978, 1082; Curtls and others, 1982). In this area, it forms a major unit of the Brooks Range alloehthon (Mayfield and others, 1982). CHUKCHI Figure 6.-Index [nap of nHusky Mountains1' and Iulgrave Hills, western Brooks Ran , Alaska, showing ]cations of measured sections B (1 f and C (2) (see fig. \ Although Martin (1970) applied the name "Kanayut Conglomeraten to part of the Upper Devonian and Lower Mississipplan sequence In the westernmost Brooks Range, most workers have described the sequence as consisting, in ascending order, of the following marine units: the Hunt Pork Shale or an unnamed fiiegrslned clastic unit, the Noatak Sandstone, the Kayak Shale, and the Utukok Formation (Dutro, 1953; Gryc and others, 1967; Tailleur and others, 1967). However, as a result of our work during the 1981 field seeson in the ''Husky Mountains'' and Mulgrave Hills in the De Long Moun- tains and Noatak quadrangles, we differentiate e non- merine unlt above the Noatak Sandstone and below the Kayak Shale that we assip to the Kanayut Conglom- erate (fig. 7, cola A). We describe this unit hereh end provide criteria for distinguishing it from overlying and underlying clastic units. This assignment con firms the transgressive-regressive conditions wlthln the Endicoti Group noted by Tailleur and others (1967) in the western Brooks Range and records a major offlap- onlap cycle similar to that of the centrai and eestern Brooks Range. The Hunt Pork Shale, whlch crops out in the Mullgrave Him and the "Husky Mountainsn in low hills, consists primarily of brown phyllitic siltstone. The 162' common presence of thin beds of ftne-grained to very fine gcafned sandstone that are locally graded suggests that they are thin-bedded turbidites deposited In Slope or prodelta settings. Because of tectonic thickening and thinning, low-grade metamorphism, and the absence of any well-exposed complete sectiona, the true thickness of the Hunt Pork is mown. The Hunt Fork Shale grades upward Into the Noatak Sandstone, whlch is probably more than 100 rn thick. The Noatak oonsists of trough-cross-stratified carbonate-cemented quartzase sandstone that contah abundant red-orange-weathering carbonate concretions. it is characterized by alternathg layera of brown-weathering fine- to medlurn-grained sandstone and oay-weathering commonly pebbly cmegralned sandstone. EHoturbated silty intervals that contain abundant mica and plmt fragments are locally present. The sandstone beds are not organized into finingupwmd cycles. We interpret the Noatak to represent deposition in innershelf and shoreline environments. The overlying Kanayut Conglomerate consists mainly of thjnnlng- and fining-upward nuvial cycles of conglomerate, sandstone, and shale (fig. 7, col. 3. The lower parts of the cycles consist, in ascending order, of channeled lightgray-weathering basal massive or crudely parallel stratified congiomerete, trough-rossstratified medium-bedded sandstone, and thin-bedded fine-grained sandstone and slltstone char acterlzed by abundant currentripple marks. The upper parts of the cycles consist of red- or brownweathering shale and siltstone that contain abundant plant and root ~wlls, paleosols marked by oxidized red, orange, or yellow horizons, and, locally, coal. The lower, sandy pacts of the cycles, which average 5 to 7 m in thickness, represent channel, point-bar, and levee deposlts of meandering streams; the upper, shaly parts record deposition on adjacent flood plains. The cycles are characterized by erosional truncation of underlying shale and by upward fining of grain size, thlnnlng of beds, and decrease In the amplitude of cross-strata. The conglomerate contains clasts as large as 3 cm. The sandstone is composed chiefly of detrital quartz and chert grains, and has, in contrast with the Noatnk Sandstone, a silica cement. Local interdigitation of the Kanayut Corrglornerate with the underlying Noatak Sandstone results in composite cycles that contaln a middle marine unlt which does not fine upward. Cycles I and 3 contain a basal channeled conglomerate that is Incised lnto underlgng shale and fines upward lnto trough-crossstratified sandstone (fig. 7, col. g). The middle parts of the cycles conslst of alternatmg carbonatecemented coarser and finer layers with abundant trough crossstratification that are identical to the Noatak Sandstone. The upper parts of the cyclea fine up ward from crossatratified silica+emented Pluvial sandstone into ripple-marked siltstone and flood-plain shale deposits containing paleosols. Cycle 2 shows a slmllar composite cycle but lacks the basal finingupward fluvial intervd. Cycle 4 is a typical Khnayut fluvlal cycle. We believe that these composite cycles represent mixed ftuvial and marine deposition, possibly under estumine conditions, along the strandline. The Kayak Shale, which is at least 40 rn thlck, overlies the Kanayut Conglomerate. Its lower part contains thin coarsening-upward cycles that consist of
Page 1 and 2: n Alas Accompli: ' I.S. GE OLOGI CA
Page 3 and 4: I CONTENTS Page A bst raet ........
Page 5 and 6: -- --A I ALASEU i nued rral expluru
Page 7 and 8: ........ igure .JB. ;5~ercn map ox
Page 9 and 10: . , ".,k a. ,.e ,\a 1 y U11 IIIUUII
Page 11: THE UNITED STATES GEOLOGICAL SURVEY
Page 15 and 16: ~ t I r n t S i m ~ ~ Alarr a ~ man
Page 17 and 18: I -1977, RelImlnary documentat!on l
Page 19 and 20: I I MaCenn, W. R., Perez, 0. J., an
Page 21: were deslgned to impMve the accurac
Page 25 and 26: I (Nilsen and others, 1981a); (2) f
Page 27 and 28: I that contains the Upper Devonian
Page 29 and 30: who found Westeqaardodina sp., posb
Page 31 and 32: Table 2 lists the means rtnd for th
Page 33 and 34: ' Noatak Vdley (fig. 129. This ice
Page 35 and 36: 3 EUMN OF MAP UNITS WAmWARY OUAERNA
Page 37 and 38: -om displacement of the cc tween th
Page 39 and 40: I US I Surlicial dcnrrua,ts [~dater
Page 41 and 42: I Plafker, George, Hudson, Travis,
Page 43 and 44: !omlensed iring vapors generated by
Page 45 and 46: and the thinning. -upward cycles .,
Page 47 and 48: Kellum, L. B., Devless, S. N., and
Page 49 and 50: 1912 sample (a mediumwey pumice blo
Page 51 and 52: various Utholagic units present Thu
Page 53 and 54: fault, and Its depositional basemen
Page 55 and 56: suggested by coplanar foUaticm and
Page 57 and 58: 1 slgnlficarrtly more umnlum (73&1,
Page 59 and 60: ecrSigtallized catadastic matrix of
Page 61 and 62: analyzed to determine whether Immob
Page 63 and 64: are tgplcd of both ocean-floor basa
Page 65 and 66: & Fclsic in~rutirt rucks 0 Eio~ite
Page 67 and 68: are Lrdlcated by coexisting @&ite+q
Page 69 and 70: (Mg3.09 pe2+ 0.69 pe 0.~1~0.01~~0.9
Page 71 and 72: westward into a narrow band that ex
Page 73 and 74:
EXF'lANATIOW 66600' Contan-Apprnimn
Page 75 and 76:
! few fold closures are preserved.
Page 77 and 78:
even thickness and conform to irreg
Page 79 and 80:
(Alnus ap.), heaths (Ericaceae, + E
Page 81 and 82:
terrane extends at least 300 krn to
Page 83 and 84:
Table 19.--6tneral petrography of M
Page 85 and 86:
were measured on 8 12-in. mass spec
Page 87 and 88:
Thin lenses of cabonate packtone to
Page 89 and 90:
The cantwell(?) Pormation south of
Page 91 and 92:
in the 18 lava flows b thermoremane
Page 93 and 94:
Upper Cretaceous shale in contact w
Page 95 and 96:
Gran tz, Arthur, 1960, Generalized
Page 97 and 98:
at 15 to 20 percent. Primary Inolus
Page 99 and 100:
addition, this factor generally def
Page 101 and 102:
Joreskog, K. G., Klovan, J. E., and
Page 103 and 104:
Mineral qItWation end r ~ k t k W e
Page 105 and 106:
1 "~_liO-/ 200 1000 B roo C E % A B
Page 107 and 108:
Smaller placer mines ere active on
Page 109 and 110:
Figme 62.-Plant fassils from the co
Page 111 and 112:
Hallam, Anthony, 1975, Alfred Wegen
Page 113 and 114:
u ALASKA Figure 65.--Sketch map of
Page 115 and 116:
F ' i a?.-Intertidal bluffs compose
Page 117 and 118:
C-s - - Figure 70.-Products of eros
Page 119 and 120:
curve is based indicates that 6.1 c
Page 121 and 122:
sampled is related to widespread ma
Page 123 and 124:
marble is alsa locally present In t
Page 125 and 126:
Bedding in the conglomerate ranges
Page 127 and 128:
1 purpose of this study wes to dete
Page 129 and 130:
The secona k~~-~ri?tation mmes that
Page 131 and 132:
epizonb'l granitic Miss, mixed with
Page 133 and 134:
40 40 Forbes, R. B., and Engels, J.
Page 135 and 136:
foliated and inequigranular end con
Page 137 and 138:
I I thy euheclra. Sphene anhedra an
Page 139 and 140:
Quartz Alkali feldspar Plagioclase
Page 141 and 142:
F'@m 85.--Sketch map of Juneau area
Page 143 and 144:
HoUister, L. 8, 1966, Garnet zoning
Page 145 and 146:
! ~ bI8oO, (IN PERMIL) ~lqp~e 87.-8
Page 147 and 148:
Figure 90.-Offshore ereas discussed
Page 149 and 150:
Preliminerg analpsis of miemfauna f
Page 151 and 152:
Survey tn Alaekai AccompUshments hh
Page 153 and 154:
Gecllogical Survey Open-File Report
Page 155 and 156:
I provenance, and tectonia sIgnific
Page 157 and 158:
Keith, T. E. C, Barnes, Ivan, afrd
Page 159 and 160:
Open-Flle Report 8P811C, 19 p. + 2
Page 161 and 162:
United States Qeological Survey in
Page 163 and 164:
, ,. nldslra poblisbe!d by Prior, D
Page 165 and 166:
60, Alaska: Offshore Technology Con
Page 167:
Author Index [Page number underscor
Page 170 and 171:
Parks. Bruce ......................
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