The purpose of this paper is to document the historical development of ideas on the interpretation of stratified (washed) drift of Quaternary age. The paper also purports to analyse the extent to which the roots of modern (twentieth century) sedimentology were influenced by glaciofluvial and glaciolacustrine studies of the nineteenth century.
In the eighteenth century and early nineteenth century the occurrence of stratified drift was commonly ascribed to the action of natural catastrophies, and especially to the Biblical Deluge (the diluvial theory). Those who subsequently accepted Lyell's drift theory in the 1830's ascribed stratified drift to the washing action of glacial currents during a great submergence. When the drift theory was supplanted by the glacial (land-ice) theory ca. 1840-1850, the modern explanation for the origin of stratified drift was forthcoming. In all three theories, however, the stratified nature of the drift was attributed to water action; the specific agent, alias flood, marine submergence, or land ice, was the crux of the dispute.
During the nineteenth and early twentierch centuries the sedimentological study of stratified drift was peripheral to the central theme of regional glaciation. Interpretative efforts were directed towards the spatial and chronologic aspects of glacial action and glacial causation; the approach was essentially morpho-stratigraphic, and to a much lesser extent morpho-sedimentologic. indeed, sedimentological studies in a “modern” context probably date from the 1850's or 1860's. Even towards the close of the nineteenth century it sufficed to know—for most investigators—that stratification in the drift was the product of water action, as opposed to ice action. Because of its rather complex and confusing bedding features, stratified drift was relegated to a low priority in the overall scheme of glacial investigation.
Notwithstanding these intrinsic handicaps, the nineteenth century witnessed steady, if unspectacular, progress in the development of sedimentological techniques and expertise. Rapid gains were made in the last quarter of the century. The literature in the second half of the century includes a description of common bedding structures (“false” or cross-bedding, compound cross-bedding, ripple marks), particle textures (mainly size, shape, roundness, and composition), and imbrication in gravels. The directional properties of cross-bedding were used as an aid in the regional synthesis of glacial events, and heavy minerals from glacial sands were examined to elucidate provenance and regional drainage directions. Observations were also made on the downstream decrease of particle size in outwash areas, and calculations were made for the rate of transport of detritus in glacial streams, and for the rate of infill of glacial lakes. As a corollary, it was also possible to calculate the rate of denudation of drainage basins in modern Alpine areas. Climate, relief, and tectonism—all essential ingredients of modern sedimentology—were topical subjects of discussion in the nineteenth century.
Some of the sedimentological studies of 80 to 100 years ago have a contemporary ring. Indeed, the pioneer workers of the nineteenth century laid a thorough groundwork for twentieth century glacial sedimentology. Specifically, their contributions to glacial stratigraphy and morphology—the channel through which glac al sedimentology evolved—were truly outstanding.
Figures & Tables
Glaciofluvial and Glaciolacustrine Sedimentation
This publication is the outgrowth of a symposium on Glacial Sedimentology that was held in Buffalo, New York, March 1972. The great interest generated in glacial phenomena during the nineteenth century had important implications and repercussions for the infant field of sedimentology. It provided its fair share of the background stimulus necessary to establish sedimentology as a separate branch of the earth sciences in the twentieth century. The time for reciprocity is now at hand; feedback from the expertise gained in the burgeoning field of sedimentology can greatly help the Quaternary specialist solve particular field problems. The last decade has witnessed a growing interest in the sedimentology of the Quaternary, and it seems appropriate now to summarize progress in the study of stratified drift, to present results of some recent studies, and to focus attention on avenues of research that should be explored in the near future.