Russian Altai in the Late Pleistocene and the Holocene CONTENT Introduction 5 Key questions related to the geomorphology of this excursion 9 Princess of Ukok 12 Part I. Upper Biya River valley and the Teletskoye Lake 16 NE Altai Regional settings and Quaternary history: General overview 16 Stop B1. Former glacial-dammed lake in the Yogach valley 23 Stop B2. Former alluvial-dammed lake in the Turachak valley 27 Stop B3. Teletskoye Lake and lacustrine terrace at Yaylyu 31 Geomorphic history of the Teletskoye Lake – Biya valley system: synthesis 35 Part II. Middle Katun River valley 39 Brief introduction 39 Stop K1. Catafluvial deposits of the high (Inya) terrace in the vicinity of the Bolshoi Yaloman River 41 Stop K2. Boulder field at km 702 51 Stop K3. High terraces of the Katun and Injushka Rivers at the Inya village 57 Stop K4. Composition and geochronology of the low (Saldzhar) terrace at the Chuya River confluence 68 Part III. Middle Chuya River valley, Kuray and Chuya Basins 73 Stop C1. Early Holocene seismic fall and dammed lake formation at the Sukhoi brook 73 Stop C2. Late Pleistocene glacial damming of Chuya at Kuektanar tributary valley 77 Stop C3. Lower Chagan-Uzun river: the Late Pleistocene maximal glacial advance 84 Stop C4. Beltir village: consequences of the year 2003 seismic hazard 87 Stop C5. Earthquake triggered giant landslides in the Taldura valley 92 Stop C6. Kuray dunes 99 3 Russian Altai in the Late Pleistocene and the Holocene Stop C7. Kuray strandlines 102 Stop C8. Early Holocene lake in the western part of the Kuray Basin: the Baratal section 108 Stop C9. The Chuya spillway upstream from the Chibit town 112 Stop C10. Old valley of Chuya, age and mechanism of abandonement 115 References 120 Supplements 125 S1. Large boulder transport 125 S2. Problems of absolute dating of glacial deposits in Russian Altai by the example of the Chagan section 130 S3. The recurrence interval of strong prehistoric earthquakes in the SE Altai (the Kuray-Chuya active zone) based on dendroseismological approach and radiocarbon analysis 133 S4. Radiocarbon chronology of the Holocene landscape evolution within the Kuray-Chuya system of intermountain depressions 135 4 Introduction INTRODUCTION (G. Baryshnikov, A. Panin) The Russian Altai is one of the world's regions where evidence has been recognized of past megafloods – the largest known fresh-water floods which discharges exceeded 1 million m³/s, or 1 Sv (Baker, 2013). More than three decades ago giant current ripples were found in Altai in the valleys of Bashkaus, Chuya, Katun and in the bottom of the Kuray Basin (Butvilovskiy 1982, 1985; Okishev 1982; Rudoi 1984), as well as in the Biya River valley (Baryshnikov 1979, 1992). A number of workers hypothesize that these features are specific facies of glacial till (Borisov and Minina 1979; Okishev 1982, 2011). However the majority of scholars interpret them as evidence of catastrophic outburst floods that resulted from water flowing from big lakes formed due to blockage of river valleys by glaciers. Later other evidence of outbursts from glacial lakes were recognized, such as spillways and distant transportation of giant rocks torn from valley sides. Paleohydraulic assessments (Baker et al., 1993; Herget, 2005; Carling et al., 2010) permit the ranking of the Altai outburst floods with depth up to 400 m, flow velocity 20-25 m/s and discharge 10-20 million m³/s close in magnitude to the well-known Missoula flooding in western USA (Baker, 2009). Several local and international workers that independently studied the Late Pleistocene and Holocene geomorphic history of Altai in the last decades have collected into this author team to present their results to the attendees of the International Association of Geomorphologists (IAG) Regional Conference "Gradualism vs catastrophism in landscape evolution" (Barnaul, Russia, July 2- 4, 2015). This guide was prepared for the 7-day (July 5-11) post-conference excursion "Russian Altai in the Late Pleistocene and the Holocene: Geomorphological catastrophes and landscape rebound". The fieldtrip is scheduled as three consecutive parts (Fig. 1): (1) Upper Biya River and Teletskoye Lake, July 5-6, stops B1 – B3; (2) Middle Katun River valley, July 7-8, stops K1 – K4; (3) Lower Chuya River – Kuray Basin – Chuya Basin, July 9-10, stops C1 – C10. General plan of the fieldtrip: July 5 8.00 Departure from Barnaul for Gorno-Altaisk 12.00-13.00 The Republican National Museum in Gorno-Altaisk 12.30-14.30 Lunch 18.30 Arrival to Artybash, accommodation 19.30 Dinner 5 Introduction Fig. 1. General map of the post-conference fieldtrip July 6 8.00 Breakfast 9.00-12.30 Stops in the Biya valley tributaries (Iogach and Turachak rivers): exposures of alluvial and dammed-lake deposits . 12.30-13.30 Lunch 14.00-19.00 Cruse in the Teletskoye Lake: Korbu waterfall, lacustrine terrace and exposure at Yaylyu. 19.00 Dinner at Artybash July 7 7.00 Breakfast 8.00-16.00 Transfer Artybash – Ongudai. Packed meals. 16.00 Accomodation and meals in Ongudai 18.00 Ethnographic entertaining program 20.00 Dinner July 8 8.00 Breakfast 8.00 – 19.00 Transfer to Aktash with five stops in the Katun and Chuya valleys: exposures of catafluvial deposits composing the upper and lower terraces of Katun, petroglyphic arts. Meals in a roadside cafe. 6 Introduction 19.00 Accomodation in Aktash 20.00 Dinner July 9 8.00 Breakfast 9.00 – 19.00 Visiting the Chuya Basin: key sections of Late Pleistocene moraine and dammed lake deposits, Beltir earthquake, Taldura seismic landslide. Several stops in the Chuya valley: Kuekhtanar glacial dam, Iron Age geoarchaeology, the early Holocene dammed lake at Baratal. Packed meals. 19.00 Dinner in Aktash July 10 8.00 Breakfast 9.00 – 14.00 Visiting the Kuray Basin: strandlines of the Kuray Lake, large gravel ripples, synthesis of the long term debates on timing and mechanism of the Kuray Lake formation and sink. 14.00 Lunch in Aktash 15.00-19.00 Examination of the abandoned Chuya valley and the young Chuya canyon with key exposures illustrating the age and mechanism of the valley rebuilding. 19.00 Dinner and farewell party in Aktash. July 11 8.00 Breakfast 9.00 – 19.00 Bus transfer from Aktash to Barnaul (600 km). Problems of the Quaternary development of Russian Altai, especially glacial history and geomorphic and sedimentological features of river valleys have been massively studied by Russian geologists and geomorphologists since the 1950th, but most results both from early and from recent times were published in Russian, which makes them unavailable for scientific community outside the former USSR. Since the early 1990th, several international teams have been working in the region and some local researchers began to publish in English. Several dozens of papers were issued in international journals and books that contain both news results and overviews, which compensate partly the deficit of English-language publications from the region. Supplemented to this fieldtrip guide is a separate volume titled "Russian Altai: superfloods, glaciation, human occupation". The volume contains12 selected papers that give general introduction into the region, overview of key problems and some principal results from the last two decades. It permits us to skip these introductory issues and to focus on description of the fieldtrip stops. However the first part (Biya valley and Teletskoye Lake) contains a short introductory chapter because no English-language publications have still been made to cover it. 7 Introduction It will become clear from the offered publications that noticeable progress has been achieved in understanding the Altaian superflood phenomena in recent decades. However many uncertainties still remain in interpretation of particular phenomena and their correlation through the fluvial system, including geomorphological and sedimentological features and geochronology of events and deposits. In this regard, we find it especially important to introduce a yet unpublished series of >30 OSL dates obtained in the last year from the Biya, Katun and Chuya valleys. Laboratory analysis was processed by Dr. Grzegorz Adamiec. Given the existence of a variety of views, we try in this guide to offer more facts and results so that to facilitate the fieldtrip attendees to elaborate their own opinions on the debated problems. Authors of the text that will also guide the excursion are: • Gennady BARYSHNIKOV, prof., Altai State University, Barnaul, Russia; • Anna AGATOVA, PhD, Institute of Geology and Mineralogy, Russian Academy of Sciences (Siberian Branch), Novosibirsk, Russia; • Paul CARLING, prof., University of Southampton, UK; • Juergen HERGET, prof., Bonn University, Germany; • Andrei PANIN, PhD, Lomonosov Moscow Sate University, Russia; • Grzegorz ADAMIEC, PhD, GADAM Centre of Excellence, Institute of Physics, Silesian University of Technology, Gliwice, Poland; • Roman NEPOP, PhD, Institute of Geology and Mineralogy, Russian Academy of Sciences (Siberian Branch), Novosibirsk, Russia. 8 Introduction KEY QUESTIONS RELATED TO THE GEOMORPHOLOGY OF THIS EXCURSION (P. Carling, J. Herget) A major key question is ‘Are the geomorphological features found in along the Katun, Chuja rivers and in the Kuray and Chuja Basins signature of catastrophic flooding? Or are they due to other geomorphological processes?’ • According to Carling, Herget and others the terraces along the river courses are giant bars deposited by a series of floods. According to Okishev they are kame terraces deposited by an extensive glacier. Can these competing hypotheses be tested? • According to Rudoy, Carling, Herget and others the rippled ground in the Kuray and Chuja Basins and along the course of the Chuja and Katun rivers are fluvial bedforms due to catastrophic flooding. Others have suggested they are gullied alluvial fans, gullied moraine or rogen moraine. Can these competing hypotheses be tested? • What are the key events in the Quaternary history of the region and how can these events be dated in time? • The altitudinal range of strandlines around the Kuray and Chuja Basins indicate multiple changes in lake level.