Notes showing that the estuary of the Derwent was occupied by a fresh-water lake during the tertiary period

Abstract

Apart from the circumstance that the extensive tertiary fluviatile and lacustrine formations of Australia have been the principal sources from which we have derived our rich treasures of gold and tin in the free state, their study from a naturalist's point of view is also peculiarly interesting from the nearness of their deposition to our own time. Many present may have noticed along the shores of the Derwent, particularly in the neighbourhood of Sandy Bay, One Tree Point, and Cornelian Bay, a series of sandy and clayey beds sometimes of considerable thickness and extent. They frequently dip irregularly at various angles, and in various directions, as if they had been much disturbed subsequent to their deposition, but they are never found at an altitude of much more than 40 feet above the existing sea level.