In the Würmian between Straubing and Deggendorf three würmian terrace bodies were build in the Danube River valley. The surfaces of the terraces are falling continuously to the recent course of the Danube River. To fix the limits of the terrace bodies by terrace-edges or differents in the niveau of the surfaces is only subordinate possible. Therefore the würmian terraces were fixed by the lithological structure of their covering sediments. This terrace specific covering sediments could be associated with three terrace areas. The oldest terrace area JWI is in the Pleniglacial characterised by CaCO3-riche depositions of loess (reworked) from the side valleys, through which the fluvial forming of the underlaying gravel body into the Early Glacial is to place. During the superposition of the JWI-terrace with pleniglacial covering sediments occurred the fluvial forming of the pleniglacial gravel body under reducing the latitude of the River valley. CaCO3-free, late glacial fluvial sands and eolian sands of the JWII-terrace were deposited after the separation of the plenglacial gravel body from the fluvial forming. A further deposition of loess (aqueous reworked) from the side valleys happened in the early Holocene. This early holocene, carbonic-rich sediments are characteristic for the JWIII-terrace, which overlying a gravel body formed in the Late Glacial.
The fluvial forming of the würmian gravel bodies shows a relationship to the incision and aggradation phase in the Danube River valley. Both of the fluvial processes were since the early Pleniglacial retrogressive, through which the building of the terraces with different old gravel bodies but identical covering sediments is characterized. In the Danube River valley between Straubing and Deggendorf the different fluvial forming of the würmian and the early holocene gravel bodies can not be related with a significant climate influence. Rather there exists a separate dynamic controlling of the processes accumulation and erosion, which can be intensified by climatic impulses.
The fluvial forming of floodplain terraces and floodplain series followed in the Holocene. In the Danube River valley between Straubing and Bogen four floodplain terraces could be differentiated one from another by the lithological structure of their high tide sediments and their stratigraphical sequence. In the early Atlantic the fluvial forming of the oldest floodplain terrace HI began and ended with a fluvial dynamic change in the channel pattern in the late Atlantic. With this change in the channel pattern from anastomosing-braided to meandering system the forming of the HII-floodplain terrace happened, which was separated in the ending Subboreal from the fluvial forming. From the late Subboreal till the 18th century the fluvial forming carried out the HIII–floodplain terrace. Since the 18th century the fluvial forming of the youngest HIV-floodplain terrace has began. The holocene valley development is characterized by a sinuous channel pattern course of the river in the Danube River valley between Bogen and Deggendorf. Here the fluvial forming of three floodplain series happened. The floodplain series are sediment-bodies piled up one over the other, they can be distinguished by their characterizing lithofacies. In the early Holocene the fluvial forming of the gravel body (Talauenschotter - basal-sediment sequence) of the oldest floodplain facies HSI set up. With the late Atlantic till the early Subboreal the sediment sequence (Talauenschotter, sandy and loamy flood sediments) of the HSI–floodplain facies was overlying by sandy high tide loams of the HSII-floodplain facies. In the Subatlantic a raising high tide activity produced the covering of the HSII–floodplain facies by youngest high tide sediments of the HSIII-floodplain facies.
With the human influence in the Danube River valley and his side-valleys during the Holocene men took influence on the flowing off from the fluvial systems. In the Danube River valley activities like cleared woodland and agriculture utilization directed to changes of the soil condition and consequently to the breaking up of the sediment, which was erosive dissolved and transported by floods. On the hills of the Bavarian Forest and the adjoining high-terrace-area the erosion of the soil began with the human influence. An influence of men in relation to the transfer of the course of the river can be excluded between Bogen and Deggendorf.
The tributary valleys of the Danube River like the Valley of the Kleine Laber River from the Bavarian Loess Rolling Hills and the Mehnach River, the Bogenbach River and the Schwarzach River from the Bavarian Forest, are influenced by the fluvial dynamics of the Danube River. Thereby the fluvial forming of the tributary valleys of the Bavarian Forest in the area of the confluence with the Danube River is controlled by the incision and accumulation phase of the Danube.
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