ESTONIAN ACADEMY
PUBLISHERS
eesti teaduste
akadeemia kirjastus
PUBLISHED
SINCE 1952
 
Earth Science cover
Estonian Journal of Earth Sciences
ISSN 1736-7557 (Electronic)
ISSN 1736-4728 (Print)
Impact Factor (2020): 0.789

Two-dimensional apparent microfabric of the basal Late Weichselian till and associated shear zone: case study from western Latvia; pp. 241–255

Full article in PDF format | 10.3176/earth.2008.4.04

Authors
Andis Kalvāns, Tomas Saks

Abstract

The examination of glacial sediments in thin sections has become a common procedure in recent years. Apparent sand grain orientation (microfabric) in thin sections is one of the key elements marking certain microstructures. In an attempt to make till micromorphology studies less subjective and investigate the orientation of sand-sized particles in tills, we have developed an image analysis procedure to measure and analyse the spatial distribution of the till microfabric. We studied 13 thin sections of the Weichselian subglacial till and basal shear zone outcropping in the Baltic Sea bluffs at the Ziemupe site in western Latvia. The results were visualized as a two-dimensional grid of rose diagrams covering the area of the thin section and were compared to macrofabric. We found that in larger areas microfabric, although much weaker than macrofabric, coincides with macrofabric orientation. In the sub-centimetre scale till microfabric in short distances appears to be highly variable both in strength and preferred orientation, and a domain-like pattern appears.


References

Benn, D. I. 1994. Fabric shape and the interpretation of sedimentary fabric data. Journal of Sedimentary Research64, 910–915.

Boulton, G. S. & Hindmarsh, R. C. A. 1987. Sediment deformation beneath glaciers: rheology and sedimento­logical consequences. Journal of Geophysical Research92, 9059–9082.
doi:10.1029/JB092iB09p09059

Boulton, G. S., Dongelmans, P., Punkari, M. & Broadgate, M. 2001. Palaeoglaciology of an ice sheet through a glacial cycle: the European ice sheet through the Weichselian. Quaternary Science Reviews20, 591–625.
doi:10.1016/S0277-3791(00)00160-8

Camuti, K. S. & McGuire, P. T. 1999. Preparation of polished thin sections from poorly consolidated regolith and sediment materials. Sedimentary Geology128, 171–178.
doi:10.1016/S0037-0738(99)00073-1

Carr, S. 1999. The micromorphology of Last Glacial Maximum sediments in the Southern North Sea. Catena35, 123–145.
doi:10.1016/S0341-8162(98)00097-6

Carr, S. 2001. Micromorphological criteria for discriminating subglacial and glacimarine sediments: evidence from a contemporary tidewater glacier, Spitsbergen. Quaternary International86, 71–79.
doi:10.1016/S1040-6182(01)00051-9

Carr, S. C. & Lee, J. A. 1998. Thin-section production of diamicts – problems and solutions. Journal of Sedimentary Research68, 217–220.

Carr, S. J. & Rose, J. 2003. Till fabric patterns and significance: particle response to subglacial stress. Quaternary Science Reviews22, 1415–1426.
doi:10.1016/S0277-3791(03)00125-2

Chaolu, Y. & Zhijiu, C. 2001. Subglacial deformation: evidence from microfabric studies of particles and voids in till from the upper Ürümqi river valley, Tien Shan, China. Journal of Glaciology47, 607–612.
doi:10.3189/172756501781831710

Danilāns, I. 1973. Chetvertichnye otlozheniya Latvii [Quaternary deposits of Latvia]. Zinatne, Riga, 312 pp. [in Russian].

Davis, J. C. 2002. Statistics and Data Analysis in Geology. Third edition, John Wiley and Sons, New York, 638 pp.

Dreimanis, A. 1936. Atšķirība starp augšējo un apakšējo morēnu Latvijā [Difference between upper and lower till in Latvia]. Mag. rer. nat. thesis, Riga, Latvijas Universitāte, unpublished manuscript, 126 pp. [in Latvian].

Dreimanis, A. 1973. Tills, their origin and properties. In Glacial Till (Leggett, R. F., ed.), Royal Society of Canada, Special Publication, 12, 11–49.

Dreimanis, A. 1989. Tills: their genetic terminology and classification. In Genetic Classification of Glacigenic Deposits (Goldthwait, R. P. & Matsch, C. L., eds), pp. 17–83. Balkema, Rotterdam.

Ehlers, J., Gibbard, G. L. & Whiteman, C. A. 1987. Recent investigations of the Marly Drift of northernwest Norfolk, England. In Tills and Glaciotectonics (van der Meer, J. J. M., ed.), pp. 39–54. Balkema, Rotterdam.

Gaigalas, A., Gudelis, V., Spriņģis, K., Konshin, G., Savvaitov, A., Veinbergs, I. & Raukas, A. 1967. Orientation of pebble long axes in the tills of the last glaciation in the East Baltic region and its relation to ice sheet shrinkage. In Baltica 3 (Gudelis, V., ed.), pp. 215–233. Vilnius [in Russian, with English and German summaries].

Hart, J. K., Khatwa, A. & Sammonds, P. 2004. The effect of grain texture on the occurrence of microstructural properties in subglacial till. Quaternary Science Reviews23, 2501–2512.
doi:10.1016/j.quascirev.2004.06.006

Hiemstra, J. F. & van der Meer, J. J. M. 1997. Pore-water controlled grain fracturing as an indicator for subglacial shearing in tills. Journal of Glaciology43, 446–454.

Juškevičs, V., Kondratjeva, S., Mūrnieks, A. & Mūrniece, S. 1998. Latvijas ģeoloģiskā karte. Mērogs 1 : 200 000. 41. lapa. Paskaidrojuma teksts un kartes [Geological map of Latvia. Scale 1 : 200,000. Sheet 41 – Ventspils. Explanatory note and maps]. State Geological Survey, Rīga, 48 pp. [in Latvian].

Kalnina, L. 2001. Middle and Late Pleistocene Environmental Changes Recorded in the Latvian Part of the Baltic Sea Basin. Quaternaria, Series A 9, 173 pp.

Kalniņa, L., Dreimanis, A. & Mūrniece, S. 2000. Palynology and lithostratigraphy of Late Elsterian to Early Saalian aquatic sediments in the Ziemupe-Jurkalne area, Western Latvia. Quaternary International68–71, 87–109.
doi:10.1016/S1040-6182(00)00036-7

Kalvāns, A., Saks, T. & Zelčs, V. 2007. 2D analysis of apparent till micro fabrics in thin sections: an example from Western Latvia. Quaternary International167–168, Supplement 1, 200 (Abstracts the XVII INQUA Congress 2007, Australia, 28 July–3 August 2007).

Khatwa, A. & Tulaczyk, S. 2001. Microstructural interpretations of modern and Pleistocene subglacially deformed sediments: the relative role of parent material and sub­glacial processes. Journal of Quaternary Science16, 507–517.
doi:10.1002/jqs.609

Konshin, G., Savvaitov, A. & Slobodin, V. 1970. Marine intertill deposits of Western Latvia and some peculiarities of their development. In Voprosy chetvertichnoj geologii 5 [Questions of Quaternary Geology V] (Danilāns, I., ed.), pp. 37–48. Zinātne, Rīga [in Russian, with English summary].

Krüger, J. & Kjær, K. H. 1999. A data chart for field description and genetic interpretation of glacial diamicts and associated sediments – with examples from Greenland, Iceland, and Denmark. Boreas28, 386–402.
doi:10.1080/030094899422118

Kuhn, M. R. 2005. Are granular materials simple? An experimental study of strain gradient effects and localization. Mechanics of Materials37, 607–627.
doi:10.1016/j.mechmat.2004.05.001

Lachniet, M. S., Larson, G. J., Lawson, D. E., Evenson, E. B. & Alley, R. B. 2001. Microstructures of sediment flow deposits and subglacial sediments: a comparison. Boreas30, 254–262.
doi:10.1080/030094801750424166

Larsen, N. K. & Piotrowski, J. A. 2003. Fabric pattern in a basal till succession and its significance for reconstructing subglacial processes. Journal of Sedimentary Research73, 725–734.
doi:10.1306/021303730725

Larsen, N. K., Piotrowski, J. A. & Menzies, J. 2007. Micro­structural evidence of low-strain, time-transgressive subglacial deformation. Journal of Quaternary Science22, 593–608.
doi:10.1002/jqs.1085

Lebourg, T., Riss, J. & Pirard, E. 2004. Influence of morphological characteristics of heterogeneous moraine formations on their mechanical behaviour using image and statistical analysis. Engineering Geology73, 37–50.
doi:10.1016/j.enggeo.2003.11.004

Meirons, Z. & Straume, J. 1979. Cenozoic group. In Geologicheskoe stroenie i poleznye iskopaemye Latvii [Geological structure and mineral resources of Latvia] (Misans, J., Brangulis, A., Danilans, I. & Kuršs, V., eds), pp. 176–268. Zinatne, Rīga [in Russian].

Menzies, J. 2000. Micromorphological analyses of micro­fabric and microstructures indicative of deformation processes in glacial sediments. In Deformation of Glacial Materials (Maltman, A. J., Hubbard, B. & Hambrey, M. J., eds), Geological Society Special Publication, 176, 245–257.

Menzies, J. & Zaniewski, K. 2003. Microstructures within a modern debris flow deposit derived from Quaternary glacial diamicton – a comparative micromorphological study. Sedimentary Geology157, 31–48.
doi:10.1016/S0037-0738(02)00193-8

Piotrowski, J. A., Larsen, N. K., Menzies, J. & Wysota, W. 2006. Formation of subglacial till under transient bed conditions: deposition, deformation, and basal decoupling under a Weichselian ice sheet lobe, central Poland. Sedimentology53, 83–106.
doi:10.1111/j.1365-3091.2005.00755.x

Punkari, M. 1997. Subglacial processes of the Scandinavian Ice Sheet in Fennoscandia inferred from flow-parallel features and lithostratigraphy. Sedimentary Geology111, 263–283.
doi:10.1016/S0037-0738(97)00019-5

Raukas, A., Mickelson, D. & Dreimanis, A. 1978. Methods of till investigation in Europe and North America. Journal of Sedimentary Petrology48, 285–294.

Roberts, D. H. &. Hart, J. K. 2005. The deforming bed characteristics of a stratified till assemblage in north East Anglia, UK: investigating controls on sediment rheology and strain signatures. Quaternary Science Reviews24, 123–140.
doi:10.1016/j.quascirev.2004.03.004

Ruszczynska-Szenajch, H. 2001. “Lodgement till” and “deformation till”. Quaternary Science Reviews20, 579–581.
doi:10.1016/S0277-3791(00)00097-4

Saks, T., Kalvāns, K. & Zelčs, V. 2007. Structure and micro­morphology of glacial and non-glacial deposits in coastal bluffs at Sensala, Western Latvia. Baltica20, 19–27.

Segliņš, V. 1987. Stratigrafiya pleistotsena zapadnoj Latvii: Avtoreferat dissertatsii kandidata geologicheskikh i mineralogicheskikh nauk [Pleistocene stratigraphy of Western Latvia: Compendium of partial fulfillment of requirements of the candidate of geological and mineralogical sciences]. Tallinn, 14 pp. [in Russian].

Stroeven, P. A., Stroeven, P. & van der Meer, J. J. M. 2005. Microfabric analysis by manual and automated stereo­logical procedures: a methodological approach to Antarctic tillite. Sedimentology52, 219–233.
doi:10.1111/j.1365-3091.2004.00690.x

Thomason, J. F. & Iverson, N. R. 2006. Microfabric and microshear evolution in deformed till. Quaternary Science Reviews25, 1027–1038.
doi:10.1016/j.quascirev.2005.09.006

Ulsts, W. & Majore, J. 1964. Roundness of hornblende grains as basis for stratigraphic subdivision of morainic deposits of the western part of the USSR. In Voprosy chetvertichnoj geologii 3 [Questions of Quaternary Geology, III] (Danilāns, I., ed.), pp. 33–61. Zinātne, Rīga [in Russian, with English summary].

Van der Meer, J. J. M. 1993. Microscopic evidences of sub­glacial deformation. Quaternary Science Reviews12, 553–587.
doi:10.1016/0277-3791(93)90069-X

Van der Meer, J. J. M. 1996. Micromorphology. In Past Glacial Environments – Sediments, Forms and Techniques, Vol. II (Menzies, J., ed.), pp. 335–356. Butterworth-Heinemann, Oxford.

Van der Meer, J. J. M. 1997. Particle and aggregate mobility in till: microscopic evidence of subglacial processes. Quaternary Science Reviews16, 827–831.
doi:10.1016/S0277-3791(97)00052-8

Van der Meer, J. J. M., Rabassa, J. O. & Evenson, E. B. 1992. Micromorphological aspects of glaciolacustrine sediments in northern Patagonia, Argentina. Journal of Quaternary Science7, 31–44.
doi:10.1002/jqs.3390070104

Van der Meer, J. J. M., Menzies, J. & Rose, J. 2003. Sub­glacial till: the deforming glacier bed. Quaternary Science Reviews22, 1659–1685.
doi:10.1016/S0277-3791(03)00141-0

Veinbergs, I. 1964. Coastal morphology and dynamics of the Baltic Ice Lake on the territory of the Latvian SSR. In Voprosy chetvertichnoj geologii 3 [Questions of Quaternary Geology, III] (Danilāns, I., ed.), pp. 331–369. Zinātne, Rīga [in Russian, with English summary].

Zaniewski, K. & van der Meer, J. J. M. 2005. Quantification of plasmic fabric through image analysis. Catena63, 109–127.
doi:10.1016/j.catena.2005.07.001

Zelčs, V. & Markots, A. 2004. Deglaciation history of Latvia. In Extent and Chronology of Glaciations 1 (Europe) (Ehlers, J. & Gibbard, P. L., eds), pp. 225–244. Elsevier.

Zelčs, V., Saks, T. & Kalvans, A. 2007. Towards revised Pleistocene stratigraphy of Western Latvia, the Eastern Baltic. Quaternary International167–168, Supplement 1, 471 (Abstracts of the XVII INQUA Congress 2007, Australia, 28 July–3 August 2007).

 


Back to Issue