Author: Ruliff S. Holway

Publisher: Forgotten Books

Published: 2016-08-30

Total Pages: 68

ISBN-13: 9781333394721

Excerpt from Physiographically Unfinished Entrances to San Francisco Bay The most northern of the entrances to San Francisco Bay which would result from the supposed further depression is the gorge through which the Russian River ows in the last twenty miles of its course. The writer has recently discussed this stream in considerable detail,6 and only the briefest resumb 'of the por tion concerning the gorge will be made here as an introduction to a consideration of its relation to the other cross-valleys de scribed. The lower Russian River is the remnant of an Old consequent stream which existed at the close of the period of peneplanation in the Coast Ranges. Slow uplift has deeply entrenched this portion of the river, but the region to the eastward has had a long history of depression, deposition and changes of level which have resulted today in the low-lying alluvial Santa Rosa Valley to the northward of the present San Francisco Bay. As said in the introduction, the Russian River ows southeasterly from the northwestern end of the canoe-shaped valley of the bay of San Francisco, until it reaches the portion locally called the Santa Rosa Valley, and then, although there is no ridge sepa rating it from the waters of the bay, it turns westward, owing through twenty miles of gorge to the ocean. The height of the indefinite water-parting between the river and the bay reaches its maximum of 113 feet in the grain fields ten miles to the northward of Petaluma. A subsidence Of 250 feet would thus extend the bay northward over Santa Rosa Valley beyond the town of Healdsburg and make the gorge Of the Russian River a salt-water estuary 200 feet and more in depth, with over 130 feet for the shallowest water between it and the present bay. The Russian River entrance to the enlarged San Francisco Bay is, then, in genetic history similar to that commonly accepted for the Golden Gate, the difierence being that the Russian River is a small stream, while the Sacramento River, the Old mouth of which has become the Golden Gate, is the major river of the state. 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."