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The “upper pit” at the Lost Chicken placer gold mine in east central Alaska contains fossils that provide information on the flora and insect fauna of interior Alaska just before the onset of global cooling at 2.5 myr. Fossils come from sediments interbedded with the Lost Chicken tephra (dated at 2.9 ± 0.4 myr—early Late Pliocene) and portray the floodplain and valley of a small creek within a region dominated by a coniferous forest richer in genera and species than the present one. Climate was wetter and less continental, and there was probably little or no permafrost. At least one other Pliocene tephra (the Fortymile tephra) occurs at the site and is also associated with plant and insect fossils. Among these fossils are extinct plants and insects like those found at other Tertiary sites in northern Canada and Alaska. The Lost Chicken sequence is the same age as the Beaufort Formation on Meighen Island, more than 1000 km to the north. Like Lost Chicken, Meighen Island sediments contain fossils representing a diverse boreal environment. This shows that the latitudinal climate gradient during early Late Pliocene time was shallower than at present and the boreal forest had a far greater latitudinal span than now.

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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.

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