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Nonmarine Catskill facies were deposited by many rivers flowing northwestward from an eastern source area and comprise a suite of sedimentary rocks that (1) thin and decrease in average grain size from southeast to northwest, (2) increase in average grain size from base to top, (3) are dominantly red in color, (4) are variable both laterally and vertically, and (5) were deposited mainly by either meandering or braided streams. The marine to nonmarine transition is a complex interval composed of various facies that represent repeated alternations of marine and nonmarine depositional environments. It is frequently many tens of meters thick. Meandering-stream deposits comprise sandy to gravelly, crossbedded, channel facies and finer-grained, overbank facies arranged in fining-upward sequences. Delta-plain meandering-stream deposition was by streams of low gradient, high sinuosity, shallow water depth, and low erosional capability. The cycles generated are usually only a few meters thick and are dominated by finer-grained floodbasin sediments. Alluvial-plain meandering-stream deposition was by streams of moderate to high gradient, moderate sinuosity, moderate water depth, and moderate to large erosional capability. The generated cycles are frequently many meters thick, dominated by the coarse-grained, channel facies, and show evidence of considerable channel erosion. The braided-stream facies comprises trough-crossbedded sand deposited in shallow to moderate water depths on an alluvial plain. These deposits are almost exclusively gray in color and are sandwiched between the delta-plain and alluvial-plain meandering-stream sequences. The end of Catskill deposition was accompanied by local erosion of the alluvial plain, basin-wide transgression, and demise of the Acadian Mountains as a source area.

Grain-size parameters and mineralogy of 30 sand samples from Farewell Spit have been studied. The foreshore, backshore, and dune environments have distinctive means, sorting, skewness, percentages of heavy minerals, and distribution of selected mineral species. Grain-size parameters and mineralogy indicate that sand is eroded from the north side of the spit and carried southwards by the wind. Mineral distribution may reflect the importance of grain shape during the erosion of sand by wind.

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