William E. Galloway, 1985. "Meandering Streams – Modern and Ancient", Recognition of Fluvial Depositional Systems and their Resource Potential, Romeo M. Flores, Frank G. Ethridge, Andrew D. Miall, William E. Galloway, Thomas D. Fouch
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A fluvial system consists of a skeleton of fluvial channel-fill facies and closely associated splay and levee facies within a matrix of floodbasin muds and organics (Fig. G-9). Fluvial systems display a wide range of variation in such basic parameters as average proportion of sand to mud and dimensions and geometry of sand bodies. Consequent-ly, they also vary in their capacity to transmit fluids. Further, within a fluvial system, systematic variations in these same parameters are observed to be both parallel and transverse to the sediment disper-sal axis.
Large fluvial complexes tend to produce integrated drainage net-works containing one or more trunk streams of the same type (i.e., meandering, braided, etc.) for large parts of the network. Deposi-tional characteristics of these trunk streams provide a logical basis for differentiating significantly different portions of a fluvial sys-tem. In a series of papers, Schumm (1960, 1972) has described rela-tionships in modern streams among sediment load transported by the channel, channel geometry, and sediment type deposited by the channel. These relationships can be quantified for modern river segments (Table G-3) and provide qualitative trends that can be applied in interpretation and classification of ancient fluvial depositional sys-tems.
The basis of SchuITn's classification lies in the empirical obser-vation of a fundamental correlation between the ratio of bed load to suspended load transported by a stream and the cross-sectional geometry of the channel (expressed as width/depth ratio). This relationship is independent of other variables, such as slope, discharge, or periodici-ty of flow. Thus, alluvial channels
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Recognition of Fluvial Depositional Systems and their Resource Potential
The understanding of fluvial environments and processes that operate within them as well as their products in the geological record is a recent development. During the past decade, facies analysis of fluvial rocks has been increasingly used to explore for and develop hydrocarbons, coal, uranium and metallic minerals. The rapid growth in the database on fluvial depositional systems coupled with the need to recognize the economic potential of their deposits has yielded numerous resources which deal with recognition and classification of the whole spectrum of fluvial systems, fluvial processes and their products, facies models of ancient fluvial deposits, and application of fluvial models to resource exploration and development. This notebook is an outgrowth of the burgeoning geological investigations of fluvial rocks and their associated potential. The notebook is divided into 11 chapters the cover methodology and classification of fluvial systems as well as modern and ancient deposits of alluvial fans, fan deltas, braided systems, meandering streams and anastomosed streams. In addition, application of facies modeling to exploration and development of hydrocarbons, coal and uranium is discussed for the Rocky Mountain region, Mid Continent, Gulf Coast and western China.