Fluvial sediments

Gravel, sand and other fluvial sediments cover large areas of Hungary. There are a number of sporadic finds every year from these sediments, but these are only locally useful and, unfortunately, provide few data relevant to classical geomor-phological terrace studies. 

The first pebble spots containing faunas not of a sporadic nature were found in the freshwater limestone underlying rocks of Buda Castle Hill (Kadic and Mottl, 1944 already containing Parelephas trogontherii). 

Extensive overlying sedimentary rocks of fluvial origin of the Great Hungarian Plain are very poor in vertebrate finds. Until the 1970s, when large-scale, accurately dated deep-boring schemes were embarked upon, there were very few data available. 

Over thirty core-boring drills have been sunk in recent years, from 100 to 1550 m in depth. They have provided on the whole rich material for palaeontological study, containing vertebrate remains unique in a worldwide context, the vast majority of 

The sediments are composed of alternate strata of sand, clay and gravel, thus comprising an apparently uninterrupted cyclic series of strata. This impression is also supported by the rich pollen findings (R6nai et al., 1972). In contrast, the vertebrate finds and the mollusc material show marked periodicity with the intermediate layers showing signs of erosional discordance (Kretzoi and Krolopp, 1972). These discrepancies continue to provoke heated debate over the reliability of analysis of this material. 

---

Particle Transport. Because many organic chemicals bind with aquatic particulate matter, particle transport can determine the fate of compounds. Sediment transport has been of interest to the engineering profession for many years. Many discussions of the dynamics of fluvial sediment transport have appeared in the literature (11, 12). As with hydrodynamic transport, one strategy for environmental modeling is to "piggy-back the transport of sorbed chemicals on a model of transport of the sediment phase. 

Kellerhals R, Bray DI (1971) Sampling procedures for coarse fluvial sediments. J Hydraulics Division ASCE97(HY8) 1165-1180... 

The concentrations of LAS found in water and fluvial sediments show great variability (see Chapter 6.3). The values found in water (0— 600 p,gL 1) [7-10] and in sediments (0-600 p-gg-1) [7,9,11,12] show the pronounced affinity of the compound for the solid phase. The partition coefficients of LAS observed in fluvial sediments range from 100 to 2600 L kg-1 [9], The maximum concentrations have been detected close to urban centres in which untreated wastewater is discharged, and a rapid rate of decrease is observed as one moves downstream from these [9,13]. Some authors have found dilution to be the main factor responsible for decreasing concentrations along the course of a river towards the sea [9,13,14], but others consider biodegradation to be the most efficient process [9,15], while Rapaport and Eckhoff [16] hold adsorption onto solids in suspension to be a major factor for LAS removal from river water. 

The detection of short-chain sulfophenylcarboxylic acids (SPCs) [2,9, 13,17,18] is clear proof of the primary biodegradation of LAS in the natural medium. In general the concentrations detected are small, one order of magnitude less than those found for LAS [2,9,13], with the exception of the river Osellino [18] where the total concentration of SPC found exceeded that of LAS. The highest concentrations are also observed near zones into which wastewater effluents are discharged [9, 18]. Both SPC and dialkyltetralines (DATSs) have also been detected in some samples of fluvial sediments [9],... 

Gumell AM, Clarke Ml (1987) Glacio-fluvial sediment transfer. Wiley, Chichester... 

Rothlisberger H, Lang H (1987) In Gumell AM, Clarke MJ (eds) Glacio-fluvial Sediment Transfer. Wiley, Chichester 207... 

Arsenic is transported with the fluvial sediments from the Himalayas (e.g. (McArthur et al., 2004)). This is the most widely accepted hypothesis at present. 

The comparison reflected by the data in Figure 18 raises the question-is it possible to measure, for example, the isotopic compositions of bivalve shells, or fish, reptilian or aquatic mammalian teeth preserved within fluvial sediments to determine how high the adjacent mountains were The implication from Figure 18 is that indeed it should be possible to estimate the precipitation weighted hysometric mean elevation of drainages sampled by such materials. Application of this approach to a paleo-case is presented below. 

Milliman J.D. and Kao J.S. (2005). Hyperpycnal discharge of fluvial sediment to the ocean Impact of Super-Typhoon Herb (1996) on Taiwanese rivers. Journal of Geology, 113, 503-516. 

Thatcher, L. L. Janzer, V. J. Edwards, K. W. "Methods for Determination of Radioactive Substances in Water and Fluvial Sediments" U.S. Geological Survey, TWRI, Book 5, 1977, Chapter A5, 95 p. 

Accomasso, G.M., Zelano, V., Daniele, P.G., Gastaldi, D., Ginepro, M. and Ostacoli, G. (1993) A study on the reproducibility of Tessier s extractions in a fluvial sediment and a comparison between different dissolution procedures in a reference material. 

Coals are generated by burial of peats, which are formed in swamps and marshes. Geographic and tectonic requirements for formation of thick peat deposits include slow subsidence, protection of the swamp from erosion by marine inundation or fluvial flood waters and a restricted supply of fluvial sediment. These requirements are met on coastal plains where most Recent peat swamps are located. Microbial activity is capable of degrading great quantities of the plant material which is the ultimate source of peat. Therefore, conditions which inhibit microbial activity are favorable for the... 

The world s 25 largest rivers transport approximately 40% of the fresh water and particulate materials entering the ocean (Milliman and Meade, 1983 Meade, 1996) (also see tables 4.2 and 4.3). Rivers transport an estimated 20 Pg y 1(l Pg = lO1 = 1 gigaton) of fluvial sediments to the coastal margin (Meybeck, 1982 Meade, 1996) associated with this sediment loading is an estimated 0.21 Pg of POC y-1 (Hedges and Keil,... 

Ramirez, A.J., and Rose, A.W. (1992) Analytical geochemistry of organic phosphorus and its correlation with organic marine and fluvial sediments and soils. Am. J. Sci. 292, 421-454. 

Whereas in the previous phases of the fauna genesis it is very difficult to extrapolate the rich material deriving from the karstic hollows to the regional sediments, in the case of the Templomhegyian substage (Lower Biharian) it is very easy. As already noted in the introduction, small mammals of the stage of fauna genesis described above, i.e. the water voles (Mimomys savini), have been identified in fluvial sediments which sometimes show considerable layer widths. 

Souchez R. A. and Lemmens M. M. (1987) Solutes. In Glacio-fluvial Sediment Tranfer An Alpine Perspective (eds. A. M. Gurnell and M. J. Clark). Wiley, Chichester, pp. 285-303. 

This point of view is supported also by the fact that the particulate load accounts for —3/4 of the present-day fluvial sediment flux (Garrels and Mackenzie, 1971a). 

Fishman, M. J., and Friedman, L. C., 1989, Methods for determination of inorganic substances in water and fluvial sediments U.S. Geological Survey Techniques of Water-Resources Investigations (Book 5 Chapter Al), 545 p. 

Much of the Fairy and Royal Cave portions of the Dukes system consists of a flat-roofed epiphreatic passage at Level A (Fig. 4) the roof is a few meters above the level of the bed of Fairy Creek outside the cave. At one stage in its history this passage was almost completely filled with bedded fluvial sediments. Subsequently, the stream flowing through the cave has removed most of the sediment fill, although remnants are present in many places. Flowstone has covered much of this remaming sediment, but banks of unconsolidated material are exposed in the walls of the cave at several sites. 

The gravels, sands and clays in Reed Chamber in the lowermost epiphreatic level undoubtedly represent fluvial sediments deposited by the stream flowing through the cave at the time, as the sands occasionally show ripple cross-lamination. 

Alternatively, the fluvial sediments of Level A may have accumulated when a roof collapse blocked water flow through the cave. It is notable that the bulk of the sediments occur upstream of a major area of collapse in the cave. 

The content of aromatic carbon varies considerably in marine and estuarine humic acids, but is, in all cases, greater than that of Mangrove Lake humic acids. This is probably a reflection of the greater contribution of vascular plant-derived material which can be expected to provide lignin-like components rich in aromatic structures. Note that the humic acids from fluvial sediments of the Potomac River are the most aromatic. Peaks at 150 and 55 ppm are characteristic of oxygen-substituted aromatic carbons typically associated with lignin of vascular plants. Humic acids from New York... 

---