A limited number of clastic lithologic associations

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support the widely accepted view that tectonism and source-rock type exert the dominant control on sandstone composition. Because various kinds of tectonic provinces exist, corresponding sandstone provinces such as cratonic-sandstone provinces, fault-block basin sandstone provinces, and others also exist. However, within these provinces anomalous sandstone compositions occur (e.g., quartz arenite in a fault-block basin), because other processes such as recycling, transportation, deposition, and diagenesis obliterate or mask the effects of tectonism. Although it normally is possible to recognize the anomalies, it is difficult to determine which processes have caused the anomaly and is almost impossible to measure the individual effect of each. Thus attempts to reconstruct the paleogeog aphy of sandstone provinces and to compare and contrast the significance of sandstone provinces in various tectonic settings are hampered.

Compositional norms for recent sand derived from a variety of source rocks, in a variety of tectonic settings, and deposited in a variety of environments are needed before the process variables that have influenced the compositions of ancient sands can be identified and measured. New and improved studies of the relative destructibility of mineral types and rock fragments also are required before reliable semi-quantitative provenance interpretation within a sandstone province is possible.

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