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New Siberian Islands Archipelago) Detrital zircon ages and provenance of the Upper Paleozoic successions of Kotel’ny Island (New Siberian Islands archipelago) Victoria B. Ershova1,*, Andrei V. Prokopiev2, Andrei K. Khudoley1, Nikolay N. Sobolev3, and Eugeny O. Petrov3 1INSTITUTE OF EARTH SCIENCE, ST. PETERSBURG STATE UNIVERSITY, UNIVERSITETSKAYA NAB. 7/9, ST. PETERSBURG 199034, RUSSIA 2DIAMOND AND PRECIOUS METAL GEOLOGY INSTITUTE, SIBERIAN BRANCH, RUSSIAN ACADEMY OF SCIENCES, LENIN PROSPECT 39, YAKUTSK 677980, RUSSIA 3RUSSIAN GEOLOGICAL RESEARCH INSTITUTE (VSEGEI), SREDNIY PROSPECT 74, ST. PETERSBURG 199106, RUSSIA ABSTRACT Plate-tectonic models for the Paleozoic evolution of the Arctic are numerous and diverse. Our detrital zircon provenance study of Upper Paleozoic sandstones from Kotel’ny Island (New Siberian Island archipelago) provides new data on the provenance of clastic sediments and crustal affinity of the New Siberian Islands. Upper Devonian–Lower Carboniferous deposits yield detrital zircon populations that are consistent with the age of magmatic and metamorphic rocks within the Grenvillian-Sveconorwegian, Timanian, and Caledonian orogenic belts, but not with the Siberian craton. The Kolmogorov-Smirnov test reveals a strong similarity between detrital zircon populations within Devonian–Permian clastics of the New Siberian Islands, Wrangel Island (and possibly Chukotka), and the Severnaya Zemlya Archipelago. These results suggest that the New Siberian Islands, along with Wrangel Island and the Severnaya Zemlya Archipelago, were located along the northern margin of Laurentia-Baltica in the Late Devonian–Mississippian and possibly made up a single tectonic block. Detrital zircon populations from the Permian clastics record a dramatic shift to a Uralian provenance. The data and results presented here provide vital information to aid Paleozoic tectonic reconstructions of the Arctic region prior to opening of the Mesozoic oceanic basins. LITHOSPHERE; v. 7; no. 1; p. 40–45; GSA Data Repository Item 2015011 | Published online 31 October 2014 doi:10.1130/L387.1 INTRODUCTION to Permian clastic rocks exposed on Kotel’ny Recent detrital zircon studies of the Paleozoic Island. It is the largest in the New Siberian succession on neighboring Bel’kovsky Island The number of geological studies and inter- Islands archipelago, located in the eastern part (westernmost island of the New Siberian est in the Arctic region have increased signifi- of the Russian Arctic. This archipelago forms Islands archipelago) also suggest an affinity cantly in recent years. The Russian Arctic in the eastern border of the Laptev Sea and rep- with Laurentia or Baltica (V.B. Ershova’s data). particular remains poorly studied. Detrital zir- resents an exposed Paleozoic–Mesozoic crustal The new detrital zircon data set from Upper con ages are a useful tool for the construction fragment. The islands were studied extensively Paleozoic strata of Kotel’ny Island (presented of paleotectonic restorations, and they represent 30–40 yr ago by Kos’ko et al. (1985), when here) helps to further evaluate the affinity of one of the key data sources for determining the detailed geological maps were constructed. Kotel’ny Island, providing important new tectonic history of the Arctic realm. As a con- The recent studies have focused on the Meso- insights into the paleogeography of the Arctic sequence, the number of provenance studies zoic and Cenozoic deposits of Kotel’ny Island, during the late Paleozoic. based on detrital zircon U/Pb ages has risen in due to their potential for containing hydrocar- Our primary objectives are to: (1) obtain U/ past years (Miller et al., 2006, 2010; Lorenz et bon source rocks and reservoirs on the adjacent Pb age dates of detrital zircons within the Paleo- al., 2008; Amato et al., 2009; Beranek et al., Laptev Shelf (Meledina, 1999; Kos’ko and Tru- zoic clastics; and (2) use the detrital zircon data 2010, 2013; Lemieux et al., 2011; Anfinson et fanov, 2002). Several contrasting paleotectonic to examine the crustal affinity of Kotel’ny Island al., 2012a, 2012b). However, there are many reconstructions have been compiled, which and test the plate-tectonic reconstructions pro- contrasting models concerning the origins, provide possible models for the affinity of the posed by Zonenshain et al. (1990) and Kuzmi- affinities, and tectonic history of the numer- New Siberian Islands. For example, Kuzmichev chev (2009). ous terranes comprising the present-day Arctic (2009) suggested that the New Siberian Islands (e.g., Beranek et al., 2010; Miller et al., 2010; were attached to the distal northeastern (in pres- GEOLOGICAL BACKGROUND Colpron and Nelson, 2011; Anfinson et al., ent coordinates) margin of the Siberian craton 2012b), with only a limited number of detrital throughout the Paleozoic–Mesozoic, whereas Kotel’ny Island is mainly composed of zircon studies carried out on Paleozoic depos- Zonenshain et al. (1990) argued that the New deformed Paleozoic deposits (Fig. 1), whereas its of the eastern Russian Arctic (Lorenz et al., Siberian Islands formed a portion of the Arctida Mesozoic and Cenozoic rocks are only locally 2008, 2013; Miller et al., 2010; Ershova et al., paleocontinent, which shared an affinity with preserved within synclines and around the 2013; Prokopiev et al., 2013). In this paper, we Laurentia until the late Mesozoic. The paleo- periphery of the island (Kos’ko et al., 1985, report detrital zircon ages from Upper Devonian magnetic study of Vernikovsky et al. (2013) 2013; Kos’ko and Korago, 2009). The Paleo- showed the differing apparent polar wander zoic–Mesozoic rocks of Kotel’ny Island are *E-mail: [email protected] paths of the New Siberian Islands and Siberia. deformed into NW-striking folds, which are 40 © 2014 Geological Society of Americawww.gsapubs.org | For permission | toVolume copy, contact7 | Number [email protected] 1 | LITHOSPHERE Downloaded from http://pubs.geoscienceworld.org/gsa/lithosphere/article-pdf/7/1/40/3045382/40.pdf by guest on 25 September 2021 Provenance of the Upper Paleozoic strata of Kotel’ny Island (New Siberian Islands) | SHORT RESEARCH 180° associated with reverse faults and thrusts of SW and NE vergence (Parfenov and Kuzmin, 2001). A The oldest Paleozoic rocks on Kotel’ny Island are Ordovician carbonates that are up to W 1.5 km thick (Kos’ko et al., 1985). The thick- East Siberian ness of Silurian deposits decreases southwest- Sea NSI ward across the island from 1200 m to 750 m, a with a facies change from predominantly car- bonates to interbedded carbonates and cherts in Fig. 1b Sea Laptev Siberi the same direction. Lower Devonian strata are <1 km thick and consist of limestones, dolo- SZ mites, clayey limestones, and clayey dolomites, Ellesmere st Island with subordinate beds of argillites and siltstones We Siberia (Kos’ko et al., 1985). FJ The Middle Devonian strata (Sokolov For- NZ mation) rest on different stratigraphic levels of 80°N Ural s SV Greenland the Lower Devonian carbonates with disconfor- W - Wrangel Is. mity, with thicknesses varying from 270 m to Timanides NSI - New Siberian Islands SZ - Severnaya Zemlya 600 m across the island. They consist of inter- Caledonide s FJ - Franz-Josef Land bedded dolomites and limestones, with beds of 70°N NZ - Novaya Zemlya carbonate breccias containing angular clasts of SV - Svalbard pebble and boulder size (up to 1 m diameter) in Caledonide the lower part of the formation. The upper part 0° is composed of limestones (Fig. 2A). The Frasnian deposits (Nerpalakh Forma- tion) mainly consist of gray argillites and silt- 137°E 139°E 141°E 143°E 145°E stones, with subordinate beds of limestone and B Anisiy Cape Berezhnykh Cape sandstone (Fig. 2A). The formation does not D E A S ra T S I B E R I exceed several hundred meters in the southwest- g o ts A ern part of Kotel’ny Island (our field observa- 76°N e N S E n A na Nerpichiy Cape tion), but according to Kos’ko et al. (1985), the y a Bel'kovsky Is. In let thickness of the Nerpalakh Formation can reach t i up to 7 km across Kotel’ny Island. Such a large a r thickness is likely to be an overestimation due to t S tectonic-induced repetition. Kotel'ny Is. Faddeev Is. The Famennian–Tournaisian deposits of a y r Chekur Formation are up to 1200 m thick. The a L formation is composed of gray and red sand- Z A P stones with interbeds of greenish gray and red T siltstones, with rare beds of bioclastic lime- E stones in the lower part of the formation. The V 75°N upper part of the formation is composed of S interbedded gray and red quartz and polymictic E sandstones, with interbeds of gravelly to pebbly A S a n n i k o v polymictic conglomerates (Kos’ko et al., 1985). 0 25 km S t r a i t The Visean–Serpukhovian strata (Taas-Ary Formation) are mainly represented by up to Legend: 1100 m of bioclastic limestones and argillites, Quaternary Middle Devonian - Fault with subordinate beds of dolomite, siltstone, Lower Carboniferous sandstone, and occasional thin lenses and beds Angular Neogene-Quaternary Upper Devonian of pebbly conglomerate. unconformity The Carboniferous succession of Kotel’ny Location of Paleogene-Neogene Silurian - Lower Devonian study samples Island is capped by an Upper Carboniferous (undivided) succession, consisting of up to 30 m Lower Cretaceous Ordovician of alternating bioclastic limestone, sandy and Middle Carboniferous - silty limestone, dolomite, carbonate breccias, Thrust Lower Jurassic and polymictic conglomerates. The Permian (undivided) succession is rep- Figure 1. (A) Regional setting of the study area. (B) Geological map of Kotel’ny Island with location resented by 180 m of argillite with subordinate of study section (modified from Parfenov and Kuzmin, 2001). beds of siltstone, sandstone, and limestone in LITHOSPHERE | Volume 7 | Number 1 | www.gsapubs.org 41 Downloaded from http://pubs.geoscienceworld.org/gsa/lithosphere/article-pdf/7/1/40/3045382/40.pdf by guest on 25 September 2021 ERSHOVA ET AL.
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