Excerpt from Triassic Stratigraphy in the Northern Part of the Culpeper Basin, Virginia and Maryland A detailed stratigraphic study of the Triassic rocks in the Culpeper basin, which began in fall 1973, shows the need to change the nomenclature of these sedimentary rocks in the basin. These rocks, which make up the Newark Group, are redefined into the Manassas Sandstone, the Balls Bluff Siltstone, and the Bull Run Formation (pl. 1) on the basis of stratigraphic relation and depositional environment. About the Publisher Forgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.com This book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully; any imperfections that remain are intentionally left to preserve the state of such historical works.