Abstract

Throughout the 19th century lacustrine rocks were widely recognized in the Tertiary of the United States and in the Devonian of Europe. This interpretation prevailed until Davis (1900) and Barrell (1916) gathered evidence that these deposits mainly formed in fluvial environments. The demise of lacustrine interpretations was rapid. For several decades geologists gave little attention to lacustrine rocks. The pioneering work of W. H. Bradley, beginning in the mid 1920s, initiated much of the current interest in lake deposits.

There are few general lists of lacustrine criteria. The most comprehensive one is that of Feth (1964) which is based on an extensive bibliography of ancient lake deposits in the western United States. On the basis of many aspects of lacustrine rocks, Picard and High (1972a) presented a general summary of lacustrine criteria. From the criteria available— summarized here—environmental reconstructions can be made with considerable confidence if sufficient facts are obtained.

With improved standards for recognition of lacustrine rocks, lacustrine studies are enjoying a minor renaissance. This has led to studies of formations in which lacustrine subenvironments are distinguished. The number of subenvironments recognized approaches the variety seen in marine marginal basins: mud-flat, beach shoreface, bar, lagoon, shoal, delta, and deep lake. The means to interpret the history of the lake basin are available now that the subenvironments and their patterns of succession have been recognized.