First Use of Current-Bedding to Determine Orientation of Strata

Abstract

IN a recent communication¹, A. Lamont has directed attention to the application of current-bedding to the determination of the orientation of strata made by John Kelly in 1864. This does not mean, however, that John Kelly was the first geologist to realize the importance of current-bedding, its mode of formation and its relation to the strata. The first, rather crude representation of current-bedding, which I was able to find, was published by MacCulloch in 1819² (vol. 3, pl. 18, Fig. 2). This figure refers to the well-known Scalpa Sandstone of Strathaird in Skye, but MacCulloch's description and explanation of this occurrence (vol. 1, p. 348) are rather inadequate. The first correct interpretation of current-bedding was given by Lyell, who in company with L. A. Necker in 1829 had examined a section at the confluence of Rhone and Arve^3,4. Lyell has also described many examples of current-bedding found in strata of different ages, including the Pre-Cambrian⁵. He was perfectly aware that the truncated parts of the laminæ indicate the upper part of the strata.