Recent investigations of loess in Ukraine have focussed mostly on stratigraphic studies of material in the west of the country (see e.g. Gerasimenko, Lanczont, Mroczek, Jary, Markovic etc.)
Also there have been some interesting geochemical investigations which have pointed out contrasts between loess in Ukraine, and in the Danube basin (see Buggle etc) and it seems likely that loess research activity in Ukraine will increase.
The loess in Ukraine can supply a test zone for the extended and improved PTD(1966) classification of events involved in the formation of loess deposits. It now becomes the PTDC(2013) system because it has become apparent that post-depositional events are as interesting as pre-depositional events. Provenance events (P) are particle making events- the formation of the material- the absolute origin of the loess deposit formation story. P events are sedimentological events, and so are T transport events. The material is transported by rivers, often for long distances, and subsequently transported again by aeolian action. D is the deposition event, when the loess deposit assumes most of its qualities, and where pedological processes begin.
As soon as the initial aeolian deposit is formed change begins: C events occur. C is important in Ukraine because C includes chernozemisation. The black soils formed in the loess help to define Ukraine- this is Black Earth country. The ground can become more loessic during C time. It can be claimed that loess formation proceeds during C time;'Loess is not just the accumulation of dust'. P: the Ukraine loess might be classic glacial loess; Tutkovskii made the glacial connection. Examination of the large geomorphology of the system indicates that northern glaciers provided the energy for particle formation. T: a large river is in place for initial large scale particle transportation. Again the geomorphology suggests a river:deposit connection. D: classic Aeolian deposition.
C: in particular chernozemisation in the loess matrix- and remarkably substantial A horizon formation. Collapsibility can increase in the C phase. Initial collapsibility depends on the formation of a meta-stable structure in the D phase. Movement of carbonates and clay minerals in the C phase enhances collapsibility( and contributes to small scale loessification).
Smalley, I.J. 1966. The properties of glacial loess and the formation of loess deposits. Journal of Sedimentary Petrology 36, 669-676.
Smalley, I.J. 1978. P.A.Tutkovskiy and the glacial theory of loess formation. Journal of Glaciology 20, 405-408.
Also there have been some interesting geochemical investigations which have pointed out contrasts between loess in Ukraine, and in the Danube basin (see Buggle etc) and it seems likely that loess research activity in Ukraine will increase.
The loess in Ukraine can supply a test zone for the extended and improved PTD(1966) classification of events involved in the formation of loess deposits. It now becomes the PTDC(2013) system because it has become apparent that post-depositional events are as interesting as pre-depositional events. Provenance events (P) are particle making events- the formation of the material- the absolute origin of the loess deposit formation story. P events are sedimentological events, and so are T transport events. The material is transported by rivers, often for long distances, and subsequently transported again by aeolian action. D is the deposition event, when the loess deposit assumes most of its qualities, and where pedological processes begin.
As soon as the initial aeolian deposit is formed change begins: C events occur. C is important in Ukraine because C includes chernozemisation. The black soils formed in the loess help to define Ukraine- this is Black Earth country. The ground can become more loessic during C time. It can be claimed that loess formation proceeds during C time;'Loess is not just the accumulation of dust'. P: the Ukraine loess might be classic glacial loess; Tutkovskii made the glacial connection. Examination of the large geomorphology of the system indicates that northern glaciers provided the energy for particle formation. T: a large river is in place for initial large scale particle transportation. Again the geomorphology suggests a river:deposit connection. D: classic Aeolian deposition.
C: in particular chernozemisation in the loess matrix- and remarkably substantial A horizon formation. Collapsibility can increase in the C phase. Initial collapsibility depends on the formation of a meta-stable structure in the D phase. Movement of carbonates and clay minerals in the C phase enhances collapsibility( and contributes to small scale loessification).
Smalley, I.J. 1966. The properties of glacial loess and the formation of loess deposits. Journal of Sedimentary Petrology 36, 669-676.
Smalley, I.J. 1978. P.A.Tutkovskiy and the glacial theory of loess formation. Journal of Glaciology 20, 405-408.
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