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Pliocene and Pleistocene Fossils from the Arctic Coast of 'Alaska and the Auriferous Beaches of Nome, Norton Sound, Alaska

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Pliocene and Pleistocene Fossils from the Arctic Coast of 'Alaska and the Auriferous Beaches of Nome, Norton Sound, Alaska DEPARTMENT OF THE INTERIOR FRANKLINK. LANE, Secretary UNITEDSTATES GEOLOGICALSURVEY GEORGEOTIS SMITH, Director Professional Paper 125-C PLIOCENE AND PLEISTOCENE FOSSILS FROM THE * ARCTIC COAST OF ALASKA AND THE AURIFEROUS BEACHES OF NOME, NORTON SOUND, ALASKA WILLIAM HEALEY DALL Publlehed January 27,1920 Shorter contributions to general geology, 1919 (Pages 2397) WASHINGTON GOVERNMENT PRINTING OFFIOE 192 0 e CONTENTS. Introduction............................................................................................ Geology. .. .. .. - - .- . .- . .- . .. .. .- .- - .. - .. - - . .. .- - - - - - .- - - - - - - - - - - - - - - - - - - .- . .- - - . .. Colville "series". .. .- .-. - .- .- - .- .-. -. - - .- -.. -. - -.- - - - - - - - -.- - - - - - - - - - -.. - - -.- -.. -. - - -.- Gubik sand.. .. - . - - -.- -.-. -. - -.. .;. -.. -. - .- - - - - .- - -.-. -. - - - -.-. - - - -.- -.. - . .. - -.-. Nome elevated beaches.. .. - .- - - - - . .- I-- - - -.- -.. - - .- - - - - - -.- - - - - -.- - - -.-. - - .- - - - - - -.- - - - - .- Indications of elevation and climate.. .. -. -. .- - - - - - - - - - -.-. - - .-. - .- -.- - - -.- -.. - - .- . Routes of migration of fauna. .. - .. - - - - - - -.-. - - - - -.. -. - -.-. -. - - - -.. Intercommunication of Atlantic and PwSc faunash Pliocene time.. .. .- .- .- - - - - - - .- . Lists of species.. .. - - - - - - - -.- .- - - - .- - - - - .. - .- .. - - .-. - -.- -.- - - - - - - .. - - .- - - - .- - .- -.. - . .- - Deecriptiom of new species. .. -. -. - -.- - - - - -.- - - - - -.. -. - -.- -.. - - - - .- .- -.- - - - .: - .- .- .- .- - Gastropods .. - - .- - - . .- . .- . .. - - - .- - .- - .. - .- - .- - .- .- - .- - - .- .. .. - .- . .. .- - .- . .- .- .- - .- . Pelecypoda.. .. - - - .- - . - . .- .. - .- - .- .- .- .- - .- .- - - - . .- - - - .- .- - .. - .- - - .- .- - - - - - - .- - .- .- - - - - - - Brachiopoda ........................................................................................ Polyzoa.. .. - .- - .- . .- . .- - .. .. .- . .. .- .. .- . .. .- . .'- . .. - - .- - - - .. - .. - - .-. - .- - . .- . - - - -.- -. ILLUSTRATIONS. page. PLATESV-VI. Alaskan fossils.... .. -. -. -. - - -.. .. .-. - -.- -.- - - - - - - -.- - - - - - - - -.- - - - - .- - - - - - - - - - - -.- -.. 36-37 I1 PLIOCENE AND PLEISTOCENE FOSSILS FROM THE ARCTIC COAST OF 'ALASKA AND THE AURIFEROUS BEACHES OF NOME, NORTON SOUND, ALASKA. INTRODUCTION. in 1898, attention was attracted to this part of Exploration of the geology of the Arctic and Alaska, and the Geological Survey, represented subarctic shores of Alaska began as early as by *. and C- Schrader, began the voyages of &tzebue and Beechey, in 1818 geologic work in the year, but it was and 1826, and a detailed reporton the verte- not until 1905 that any invertebrate fossils brate fossils found there, with a wealth of were received from the region; in that year a illUBtration, was made by Sir john ~i~h~d~~~small lot of nine species received by F. H. Moffit, in 1854, in the zoology of the voyage of the from Mr. J. J. p. Beaver, of Nome, were sub- ~~thi~~of importance bearing on mitted to me, and later a report on them was the ti ti^^^ invertebrates of this region ap- published in the American Journal of S~ience.~ pears in the literature of the nineteenth ten- The attaching to these fossilrJ was so turgr, and but lit& on those of fhe older form* yeat that the members of the Survey working tions. A search of the marine sandstone m the region were urged to make special exer- strata on the right bank of the Yukon near tions t~ a larger series. Nulato, made by me in 1867 and 1868, dis- In 1908 E.%f. P. S. Smith, and R. D. dosed onba few tracesof fossils bdonging to Mesler succeeded in obtaining a considerable the genus ~~26sand led to the supposition number of specimens from various localities in that the age of the deposit might be Tertiary, the vicinity of Nome, of which I Prepared a but later investigations place it in the Meso- prelimka~list. ' aoic. 'While I wasin the Coast sumegservice In the summers of 1912 and 1914 collections in 1880 the Pleistocene deposits in Kotzebue were made on the Arctic coast of Alaska at sound and near in^ strait previously Peard Bay, about 30 miles southwest of Point referred to by Chamisso, Beechey, and Rich- Barnow, and at Carter Creek, Camden Bay, ardson were examined,' and numerous verb about 1 mile from the coast, by E. de K. bfig- brate remainswere collected; but, vFith the well. A Small series of specimens submitted exception of a species of PWium., no inverte- by Leffingwell to the United States Geological brates were found. Survey was determined by me and considered, With the explorations of F. C. Scbader and to belong to a stratum of the same Pliocene W. J. Peters, of the '~nitedStates Geological age as those obtained farther east on the Arctic Survey, in 1901 a the fkst really systematic Schrider and geologic reconnaissance of the Arctic coast of GEOLOGY. Alaska was begun- They described the strati- fication of the coastal deposits and collected COLVILLE "SEBXES." marine invertebrate fossils from them, part of The portion of the Colville "series" referred which were submitted to me and determined to the later Tertiarg is thus described by to be of Pliocene age. A brief summary of %bader:E the species Was prepared for the abovecited ~biaportion of tbs sfction ia practically free from indu- report. rated rock. It con~istsof nearly horizontally stratified When gold was discovered in the beach sands be& of begray, slate-colored, or ash-colored calcareous of the north coast of Norton Sound, near Nome, 8, Jo, ,,,,*m., ~01.a, pp 457,lW. 'Moat, F. H., Geology of the Nome and Grand Central quadrangles, 1 h.Jour. Scli., M ser., vol. 21, pp. 104-111,1881. Illasga: U. 8. Wl. Burvey Bull. &33, pp. W6,1013. 9 U. 8. hLBmy Pro2 Peper 20,1804. 6 U. 8. Oeol. Survey Prof. Paper 20, pl. 83, pl. 14, A, 1804. Ismoo-19 " 23 2 4 SHORTER CONTRIBUTIONS TO GENERAL GEOLOGY, 1919. silts, containing faunal remains. It is tentatively referred NOME, ELEVATED BEACHES. to the Pliocene on the basis of fossils collected in place by the writer in the bluff (near its top) on the west side of the On the south side of Seward Peninsula (orig- Colville about a mile north of the seventieth parallel. inally given the native name Eaviiak), on the The section assigned to the Pliocene horizon north shore of Norton Sound, the gold prospec- at Carter Creek, 1 mile from the coast of Cam- tors have revealed the presence of a series of den Bay, on the Arctic shore of Alaska, was ancient beaches the gravels of which contain measured by Leffingwell as follows: numerous marine fossils, including a cowid- erable proportion of extinct species leading Section at Carter Creek. to their identification as of Pliocene age. In Top. Feet. referring the horizon containing- the numerous A. Sand with intermixed humus.. .................. 30 extinctspecies to a pre-Pleistocene age my B. Sand without fossils, some gravel.. ............. 80 conclusions rest intirely upon the paleontolo- C. Pale-gray sand with marine fossils.. ............ 100 gic evidence. It is proper to state that P. S. The fossils appear from the collections to be Smith and A. H. Brooks, of the Geological most abundant in the lower 100 feet of the Survey, from physiographic observations, are section. disposed to assign a Pleistocene age to the GTJBIK SAND. beaches. In regard to the succession of the strata there is no difference of opinion. Schraderl describes the supposed Pleistocene The present beach near Nome may be consid- deposit of the Colville River region as follows: ered the " fist beach." The "second beach " Besides the Tertiary Colville aeries, which underlies the lies inland, at an irrepular" distance that varies coastal plain along Colville River, the section here com- with the topography but is evewhere less than ~Gesdeposits supposed to be Pleistocene. Of a mae, and has an elevation sea level of probably the most important and interesting is a surficlal deposit of brownish sand or loam about 10 to 15 feet in 37 feet. The "third beach," some 23 to 34 thickness, which unconformably overlies the beds of the miles inland, has been elevated to the height of Colville series, apparently as a continuous mantle. * * * 79 feet above the sea.3 Between the second and The deposit consists of fine sand, with apparently an ad- third beaches are several less well-dehed inter- mixture of considerable silt. In some localities it seems mediate beaches, one of which is 22 feet above to be more sandy toward the bsse and more eacthy toward the top, where it terminates in from one to several feet of sea level, thus being lower than the second dark-brown or black humus. clothed at the surface with beach, to the south of it. Between the second moss and a little grass. It ia ordinarily free from gravel, beach and the present bsach shafts have been but in several instances subangular cherty pebbles, rang- sunk to a depth of 65 to 70 feet which reach at ing from mere sand grains to fragments as large as one- about 20 feet below the present sea level the fourth inch in diameter, were found. These occur very scatteringly and are sometimes roughened, as if wind worn. oldest beach of all those now known, which has In some localities a fine gravel seems to intervene between locally received the name submarine beach or the base of the deposit and the underlying Tertiary beds, beaches. These beaches have been described as if representing the basal part of the deposit. The de- in detail byMoffit in the bulletin
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