Quaternary International xxx (2016) 1e25 Contents lists available at ScienceDirect Quaternary International journal homepage: www.elsevier.com/locate/quaint Tephra layers of in the quaternary deposits of the Sea of Okhotsk: Distribution, composition, age and volcanic sources * Alexander N. Derkachev a, , Nataliya A. Nikolaeva a, Sergey A. Gorbarenko a, Maxim V. Portnyagin b, c, Vera V. Ponomareva d, Dirk Nürnberg b, Tatsuhiko Sakamoto e, Koiji Iijima e, Yanguang Liu f, Xuefa Shi f, Huahua Lv f, Kunshan Wang f a V.I. Il'ichev Pacific Oceanological Institute, FEB RAS, Baltiyskaya st., 43, Vladivostok, 690041, Russia b GEOMAR Helmholtz Centre for Ocean Research, Wischhofstrasse, 3, Kiel, Germany c V.I. Vernadsky Institute of Geochemistry and Analytical Chemistry, RAS, Moscow, Russia d Institute of Volcanology and Seismology, FEB RAS, Piip Boulevard, 9, Petropavlovsk-Kamchatsky, 683006, Russia e Institute of Biogeosciences, Japan Agency for Marine-Earth Science and Technology (JAMSTEC), 2-15 Natsushima-cho, Yokosuka, 237-0061, Japan f First Institute of Oceanography, SOA, Xian-Xia-Ling Road, 6, Qingdao, 266061, China article info abstract Article history: The fullest summary on composition, age and distribution of 23 tephra layers detected and investigated Available online xxx in the Okhotsk Sea Pleistocene-Holocene deposits is presented. Seven tephra layers are surely identified with powerful explosive eruptions of volcanoes of Kamchatka, Kurile and Japanese Islands. For them, the Keywords: areas of ash falls including which weren't revealed earlier on the land are specified and established. It is Tephra estimated that explosive eruptions of volcanoes of the Kamchatka Sredinny Range were the sources for Tephrostratigraphy three tephra layers. Complex investigations of morphological, mineralogical and chemical composition of Quaternary deposits tephras including composition of rare and earth-rare elements (electron microprobe analysis and laser Sea of Okhotsk Geochemistry of volcanic glasses ablation method - LA ICP MS) have been made for all studied layers. They were a basis for tephros- tratigraphic correlation of the regional deposits promoting to specification of stages of volcanic explosive activity in this region. © 2016 Elsevier Ltd and INQUA. All rights reserved. 1. Introduction of their activities that cannot be reliably ascertained without investigating the properties of separate interlayers of tephra. In The interlayers of the volcanic ashes (tephra) in the continental addition, the tephra interlayers are very efficient markers for and marine deposits contain the critical information of history and stratigraphic study of the sedimentary sequences and dating of past character of volcanic eruptions. In the events of the violent volcanic events (Addison et al., 2010; Jensen et al., 2011; Hamann et al., eruptions, an ash falls at spots being at distances of thousands ki- 2008; Hasegawa et al., 2011a, 2011b; Lowe et al., 2008; Lowe, lometers from the eruption centre while the substance related to 2011; Nakagawa et al., 2002, 2008; Nakamura, 2016; Nakamura the eruptive cloud can have effect on the natural environment et al., 2009; Preece et al., 2011; Ponomareva et al., 2015a; Smith including one on the global scale (Ambrose, 1998; Ehrmann et al., et al., 2002, and others). 2007; Hamann et al., 2008). Finally, the catastrophic character of In recent decades, in the entire world, the work on documenting the volcanic explosions and their destructive effect on the envi- and age dating of the greatest explosive eruptions is carried out ronmental situation and human life and activities exact to predict (Crosweller et al., 2012; Newton et al., 2007; Siebert and Simkin, the future behavior of particular volcanoes and to gain the 2002, and others). However, it should be noted that the global knowledge of possible spatial distribution of the harmful products catalog of such eruptions even over the past thousands years is nowhere near full: up to now, many greatest eruptions were not revealed. In addition, even for the established explosive eruptions, * Corresponding author. the tephra distribution area is often unknown and, as a conse- E-mail addresses: [email protected] (A.N. Derkachev), mportnyagin@ quence, it is impossible to evaluate a volume of products thrown out geomar.de (M.V. Portnyagin), [email protected] (V.V. Ponomareva), by an eruption and to determine the extent of eruptions. This makes [email protected] (T. Sakamoto), xfshi@fio.org.cn (X. Shi). http://dx.doi.org/10.1016/j.quaint.2016.07.004 1040-6182/© 2016 Elsevier Ltd and INQUA. All rights reserved. Please cite this article in press as: Derkachev, A.N., et al., Tephra layers of in the quaternary deposits of the Sea of Okhotsk: Distribution, composition, age and volcanic sources, Quaternary International (2016), http://dx.doi.org/10.1016/j.quaint.2016.07.004 2 A.N. Derkachev et al. / Quaternary International xxx (2016) 1e25 it difficult to study the productivity and dynamics of the volcanic presented according to a classification (Katoh et al., 2000). A min- activity as well as the impact of volcanism on the environment and eral component of heavy (more than 2.85 g/cm3) fraction of ashes climate. So, the present differences in evaluating a role of volcanism with grain size of 0.05e0.1 mm was determined by the immersion as a factor of influence on the environment result from the method under the polarization microscope with count of not less incompleteness of the explosive eruptions record. Only an identi- than 300 mineral grains. The refraction index of volcanic glasses fication of tephra in the distant sections using data of its age and was determined by K. Iijima in JAMSTEC (Japan) using the material composition offers an opportunity to determine the dis- immersion-thermal method on the RIMS-86 (RI measurement tribution area and volume of tephra as well as magnitudes of system, Kyoto Fission) (Supplement 2), partially under the micro- eruptions which is crucial for understanding of the volcanism dy- scope in the immersion liquids (Derkachev et al., 2012). namics and evolution (Addison et al., 2010; Derkachev and All the layers of tephra from the deposits of the Sea of Okhotsk Portnyagin, 2013; Hasegawa and Nakagawa, 2016; Hasegawa et al., being at our disposal were examined by the unified procedure in 2011a, 2011b; Ponomareva et al., 2013a, 2013b, 2015b, and others). the electron microprobe JEOL JXA 8200 in the Leibniz Institute for The interlayers of tephra were found out in many marine and Ocean Research, now GEOMAR (Helmholtz Centre for Ocean continental deposits of the Pleistocene-Holocene age within the Research, Kiel, Germany) (Supplement 3). Investigations, carried north-west sector of the transition zone from the Asian continent out with the use of this method, allowed also to specify chemical to the Pacific Ocean. They were studied in sufficient detail on land composition of tephra. Volcanic glasses of this tephra were close to the Japanese Islands, Kamchatka and, to a lesser extent, analyzed earlier on electronic microscope Quanta-2000 with the Kurile Islands (Arai et al., 1986; Aoki and Machida, 2006; Braitseva energy-dispersive spectroscopy (EDAX) in FIO (Qingdao, China) and et al., 1993, 1997, 1998; Endo et al., 1989; Hasegawa et al., 2008, microprobe Cameca SX5 (GEOMAR, Kiel, Germany) (Gorbarenko 2009, 2011a, 2011b; Hasegawa and Nakagawa, 2016; Kimura et al., 2002; Derkachev et al., 2012; Kaiser, 2001); data obtained et al., 2015; Machida and Arai, 2003; Melekestsev et al., 1997; were used as additional source for correlation of sediment cores. Nakagawa et al., 2008; Nakagawa and Ohba, 2003; Pevzner, 2015; Using the microprobe JEOL JXA 8200, an analysis of volcanic Ponomareva et al., 2004, 2007; Razzhigaeva et al., 2011, 2016; glasses was performed by the defocused up to 5 mm electron beam Satoguchi and Nagahashi, 2012; Suto et al., 2007; Zaretskaya at accelerating voltage of 15 kV and current of 6 nA. For the device et al., 2001, 2007; Yamamoto et al., 2010, and others). However, calibration and monitoring of analyses quality, the natural certified despite the certain progress in the study of the region tephros- samples of volcanic glasses (basalt glass USNM 113498/1 VG-A99, tratigraphy, the North-West Pacific Ocean including the Sea of rhyolite glasses USNM 72854 VG568 and KN-18) and minerals Okhotsk remains to be poorly understood. (scapolite USNM R6600-1) were used (Jarosewich et al., 1980; Over the past fifteen years, during complex expeditions with the Mosbah et al., 1991). The results of analysis were corrected in participation of the Russian, German, Japanese and Chinese re- accordance with the CITZAF program. Every analytic session searchers in the Sea of Okhotsk, 23 tephra layers of in the including 15e40 h of operation of the instrument in autonomous Pleistocene-Holocene deposits were found out in more than 85 mode in the previously planned coordinates of measurement sediment cores (Fig. 1, Supplement 1). Data on them were pre- points was accompanied by analyses of the basic standards (rhyo- sented with different level of detail in a number of publications lite, basalt and scapolite) at the beginning, every 50e60 analyses (Derkachev et al., 2004; Derkachev and Portnyagin, 2013; and at the end of session. Based on these measurements, the Gorbarenko et al., 2002; Derkachev et al., 2011, 2012; Sakamoto correction factors considering a possibility of a slight calibration et al., 2005, 2006; Aoki, 2008 and others). In this paper, we pre- shift in a time of analysis were calculated for each analytical ses- sent the fullest summary on composition, age and distribution of 23 sion. In most cases, the values of factors did not exceed those of layers of tephra detected and investigated by us in the Sea of standard error of measurements of standards. After introduction of Okhotsk deposits. corrections into the measured data, all analyses of glasses were resulted in the sum of element oxides of 100% and used for con- 2.