A new technique for identifying rock-avalanche-sourced sediment in moraines and some palaeoclimatic implications

Transcription

1 GSA DATA REPOSITORY SUPPLEMENTARY INFORMATION A new technique for identifying rockavalanchesourced sediment in moraines and some palaeoclimatic implications Natalya V. Reznichenko 1*, Timothy R.H. Davies 1, James Shulmeister 2, Stuart H. Larsen 3 1 Department of Geological Sciences, University of Canterbury, Private Bag 4800, Christchurch, New Zealand 2 School of Geography, Planning and Environmental Management, University of Queensland, St Lucia, Queensland 4072, Australia 3 School of Biological Sciences, Monash University, VIC 3800, Melbourne, Australia * natalya.reznichenko@pg.canterbury.ac.nz; natashrez@gmail.com 1

2 SUPPLEMENTARY TABLE DR1: Location and characteristics of the sampled rock avalnches deposits, New Zealand and Norway. Rock avalanche Location Lat Long Lithology Volume x10 6 m 3 Age, years BP Vertical drop, m Coleridge Acheron Aoraki/ Mt. Cook Mt. Beatrice Mt. Round Top Mt. Wilberg Mt. Vora Coleridge lake, Ryton River, NZ Acheron stream, NZ Tasman Glacier, supraglacially, NZ Hooker Glacier, supraglacially, NZ West coast, NZ West coast, NZ Inner Nordfjord, lake Torheimsmyra, Norway 43 16S 43 19S 43 35S 43 38S 42 53S 43 09S 61 44N E E E E E E 6 31E greywacke sandstones " " " Haast schist " granitic gneiss , Lee et al., 2009; 2 Smith et al., 2006; 3 McSaveney, 2002; 4 Reznichenko et al., 2011; 5 Allen et al., 2011, 6 Wright et al., 1998; 7 Chevalier et al., 2009; 8 Aa et al.,

3 SUPPLEMENTARY TABLE DR2: Location and description of the sampled deposits of glacial origin, New Zealand, Norway and Russia. Glacier Location Sampled deposit Lat Long Franz Josef Westland, New Terminal moraines S E Zealand Franz Josef Fox Franz Josef Franz Josef Fox Terminal moraines Terminal moraines 1999 Lateral true left moraine Supraglacial debris, 2009 Deadice cover, S S S S S E E E E E Bødalsbreen Brenndalsbreen Briksdalsbreen Kjenndalsbreen Bergsetbreen Nigardsbreen Jostedalsbreen, Norway Terminal moraines, 2000; deposit at terminus 2010 Terminal moraines 2000, Terminal moraines 2001; Terminal moraines 1997 lake cost; 1997 true right Terminal moraine 2000 Terminal moraine 2000; supraglacial debris Basal debris at terminus N N N N N N N N N N N E E E E E E E E E E E Weichselian ice sheet over Fennoscandia Mueller Waiho Loop moraine SE Baltic coast, Kaliningrad region, Western Russia Aoraki/Cook National Park, New Zealand Westland, New Zealand Till from continental glacier, c.a ka BP moraine Terminal moraine, river outcrop; Terminal moraine, old swing bridge outcrop Tatare Stream outcrop N S S S E E E E 3

4 SUPPLEMENTARY FIGURE DR1. Location of sampled rock avalanche deposits (red) and the sediment from glacial environments (yellow), the Southern Alps, New Zealand (on the left) and Jostedalsbreen, Norway (on the right). SUPPLEMENTARY FIGURE DR2. Location of the sampled basal till from a continental glacier, Weichselian ice sheet over Fennoscandia, Western Russia, on the Baltic Sea coast, of the deglaciation period after LGM (according to the Donner, 1995) with respect to the Jostedalsbreen ice cap, Norway. 4

5 SUPPLEMENTARY FIGURE DR3. Examples of sampled rock avalanche (RA) deposits where red arrows indicate the samples points: A. Acheron RA deposit resting on alluvial gravels, outcrop along the Acheron stream, Canterbury, New Zealand. B. Aoraki/Mt. Cook 1991 RA deposit on the ablation zone of the Tasman Glacier, Aoraki/Mt. Cook National Park, New Zealand, the sample was recovered about 0.5 m below the surface. SUPPLEMENTARY FIGURE DR4. Examples of the sampled modern moraines in New Zealand and Norway and Holocene moraines at Aoraki/Mt. Cook National park, New Zealand, where red arrows indicate the sampling sites: A. The Franz Josef Glacier, New Zealand terminal (push/dump) moraine of B. The Brenndalsbreen Glacier, Norway, terminal moraine of 2001, with a person for the scale in circle. C. The Mueller Glacier terminal moraine at Aoraki/Mt. Cook, New Zealand, with outcrop at the site of the old swing bridge. D. The lateral moraine on the true left side of the Mueller Proglacial Lake, New Zealand. This is typical of the moraines where no outcrop was available. 5

6 SUPPLEMENTARY FIGURE DR5. Comparison of the polished mounted grains of the particles from different environments, SEM images: a. Basal sediment at front position of the Nigardsbreen, 2010, Norway; b. Supraglacial sediment at the Bergsetbreen stagnant ice, Norway; c. Continental glaciation till sediment, Western Russia; d. Mt. Vora RA sediment, Norway; e. Waiho Loop moraine sediment, New Zealand; f. RA sediment traces in the Mueller Glacier terminal moraine, river outcrop, New Zealand. 6

7 SUPPLEMENTARY FIGURE DR6. Grain Size Distribution curves for rock avalanche sediments (top) and modern moraine of glaciers at Norway and West Coast at New Zealand (bottom), which show the volume frequency (%) of the material that finer than 63 microns (4Ф), analysed on Saturn DigiSizer 5200 Laser Particle Size Analyzer (see Supplementary Table 1 and 2 for locations). Note the more homogenous distribution for the rock avalanche sediment and the significant amount of finer (< 4 microns) size grains (top), whereas for the glacial sediment the finer grains (< 4 microns) are minor with a prevalence of silts (> 4 microns). Because of the difficulty of disaggregating RA sediments, the amount of finer grains (< 4 microns) for the RA deposit must be regarded as a minimum. 7

8 SUPPLEMENTARY REFERENCES Aa, A.R., Sjåstad, J., Sønstegaard, E., and Blikra L.H., 2007, Chronology of Holocene rock avalanche deposits based on Schmidthammer relative dating and dust stratigraphy in nearby bog deposits, Vora, inner Nordfjord, Norway: The Holocene, v. 17, p Chevalier, G., Davies T.R.H., McSaveney, M.J., 2009, The prehistoric Mt. Wilberg rock avalanche, Westland, New Zealand: Landslides, v. 6, p Donner, J.J., 1995, The Quaternary history of Scandinavia: Cambridge, New York, Cambridge University Press, 200 pp. Lee, J., Davies, T.R., and Bell, D.H., 2009, Successive Holocene rock avalanches at Lake Coleridge, Canterbury, New Zealand: Landslides, v. 6, p Reznichenko, N.V., Davies, T.R.H., and Alexander, D.J., 2011, Effects of rock avalanches on glacier behaviour and moraine formation: Geomorphology, v. 132, p Smith, G.M., Davies, T.R., McSaveney, M.J., and Bell, D.H., 2006, The Acheron rock avalanche, Canterbury, New Zealand morphology and dynamics: Landslides, v. 3, p Wright, C.A., 1998, The AD 930 longrunout Round Top debris avalanche, Westland, New Zealand: New Zealand Journal of Geology and Geophysics, v. 41, no. 4, p