ILLUSTRATIONS. PLATE I. Map showing the outlines of the regions.... II. Summary of the published Cretaceous sections for each region..... FIG. 1. Vertical section of the New Jersey Cretaceous series... 2. Section from Philadelphia to Atlantic City 3. Section from Metuchen to Cape May, New Jersey 4. Section from Haywood to New Berne, North Carolina........ 6. Section from Parker County to Navarro County, Texas.. Page 72 246 268 79 80 82 92 108 118 134 7 LETTER OF TRANSMITTAL. DEPARTMENT OF THE INTERIOR, DIVISION OF GEOLOGIC CORRELATION, Washington, D. C., April 1, 1891. SIR: I have the honor to transmit herewith a memoir by Dr. Charles A. White on the Cretaceous of North America, prepared for publication as a bulletin. The Division of Geologic Correlation was created for the purpose of summarizing existing knowledge with reference to the geologic formations of North America, and especially of the United States; of discussing the correlation of formations found in different parts of the country with one another and with formations in other continents; and of discussing the principles of geologic correlation in the light of American phenomena. The formations of each geologic period were assigned to some student already well acquainted with them, and it was arranged that he should expand his knowledge by study of the literature and by field examination of classic localities, and embody his results in an essay. The general plan of the work has been set forth on page 16 of the Ninth Annual Report of the Survey, and on pages 108 to 113 of the Tenth Annual Report, as well as in a letter of transmittal of Bulletin No. 80. Two of the essays resulting from this work have already been presented. The first, by Prof. H. S. Williams, pertains to the formations of the Carboniferous and Devonian, and constitutes Bulletin No. 80. The second, by Mr. Charles D. Walcott, pertains to the formations of the Cambrian, and constitutes Bulletin No. 81. The present essay is the third of the series, and others will follow. Dr. White discusses the American Cretaceous formations by districts so chosen and arranged as to constitute a series, and through this discussion divides the formations into two series, which he calls Upper Cretaceous and Lower Cretaceous. These names as used by him have a purely American application and are not believed to coincide with the upper and lower divisions of the European Cretaceous. |
