Geology and Biology of North Atlantic Deep-Sea Cores
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If you do not need this publication after it has served your purpose, please return it to the Geological Survey, using the official mailing label at the end UNITED STATES DEPARTMENT OF THE INTERIOR GEOLOGY AND BIOLOGY OF NORTH ATLANTIC DEEP-SEA CORES SUMMARY, FOREWORD, AND GENERAL INTRODUCTION PART 1. LITHOLOGY AND GEOLOGIC INTERPRETATIONS PART 2. FORAMINIFERA GEOLOGICAL SURVEY PROFESSIONAL PAPER 196-A UNITED STATES DEPARTMENT OF THE INTERIOR Harold L. Ickes, Secretary GEOLOGICAL SURVEY W. C. Mendenhall, Director Professional Paper 196-A GEOLOGY AND BIOLOGY OF NORTH ATLANTIC DEEP-SEA CORES BETWEEN NEWFOUNDLAND AND IRELAND SUMMARY OF THE REPORT FOREWORD, BY C. S. PIGGOT GENERAL INTRODUCTION, BY W. H. BRADLEY PART 1. LITHOLOGY AND GEOLOGIC INTERPRETATIONS By M. N. BRAMLETTE AND W. H. BRADLEY PART 2. FORAMINIFERA By JOSEPH A. CUSHMAN AND LLOYD G. HENBEST UNITED STATES GOVERNMENT PRINTING OFFICE WASHINGTON : 1940 For cale by the Superintendent of Documents, Washington, D. C. ------- Price 30 cents CONTENTS Page Page Summary of the report._____________________________ VII Part 1. Lithology and geologic interpretation—Contd. Foreword, by C. S. Piggot___________________________ XI Evidence of bottom currents___--__---_--------_- 14 General introduction, by W. H. Bradley.______________ XIII Submarine slumping. ___________________________ 15 Significance of the investigation._________________ XIII Carbonate content of the sediments- _______ _______ 17 Location of the core stations.____________________ XIV Sulphates__ ____________________________________ 21 Personnel and composition of the report. __________ XIV Siliceous organisms.___________________________ 21 Methods of sampling and examination_____________ XIV Role of mud-feeding organisms ___________________ 22 Part 1. Lithology and geologic interpretations, by M. N. Mineralogy of the clastic sediments.______..-___._ 23 Bramlette and W. H. Bradley______________-_______ 1 Spectroscopic tests._____________________________ 25 Examination and analysis of samples._____________ 1 Porosity of the sediments._______________________ 26 Acknowledgments _ _____________________________ 2 Mechanical analyses.____________________________ 28 Presentation of data.___________________________ 2 Basaltic pyroclastics and their alteration.__________ 30 Stratigraphic units._____________________________ 2 Volcanic rock in core 11_._______________________ 32 Volcanic ash zones__________________________ 2 Basaltic mud in core 10________________________ 32 Glacial marine deposits______________________ 3 Part 2. Foraminifera, by Joseph A. Cushman and Lloyd G. Correlation of zones represented in the cores.______ 5 Henbest.________________________________________ 35 Interpretation of the glacial marine succession ______ 7 Preparation of samples-_-_-____----_-__-_------- 35 Sources of detritus.______'___________________ 7 Acknowledgments___ _ _________________________ 35 Temperature of the ocean, as indicated by the Distribution in the cores and list of species___.____ 35 deposits. _________________________________ Pelagic Foraminifera-___________________________ 39 Interpretation of the glacial marine zones in Bottom-living Foraminifera______________________ 46 terms of stages or substages of the Pleistocene _ 10 Bathymetric distribution ________________________ 48 Post-glacial climatic changes_________________ 12 Temperature indications.________________________ 49 Rate of deep-sea sedimentation.__________________ 13 Age and correlation____-________________________ 49 ILLUSTRATIONS Page PLATE 1. Bathymetric chart of a part of the North Atlantic Ocean showing the location of the core stations._______________ xv 2. Longitudinal sections of the air-dried cores_-________--_____--___---___--_-_______-_________--_-____--__-_ xv 3. Diagram showing the lithology and correlation of litholqgic zones in the cores___________________________________ 4 4. Diagram showing Cushman and Henbest's interpretation of water temperatures indicated by the pelagic Foram inifera- _____________________________________________________________________________________________ 4 5. A, Fecal pellets or filled borings in basaltic mud; B, Fecal pellets or filled borings in foraminiferal marl__ _________ 32 6. Standard pyramid diagram showing the size distribution, kinds of organisms, and mineral particles in four types of sediment_ __-______________________________________________________-_____--_____-___--------_--_--- 32 7. A, Zeolite crystals in clayey rock; B, Upper surface of the clayey rock, which is interpreted as an alteration product of basaltic lava; C, Palagonite rims surrounding fragments of unaltered basaltic glass; D, Foraminifera shells replaced by a zeolite.________________________________---____________-_____--____._------__----_----_ 32 8-10. Foraminifera from the North Atlantic deep-sea cores____________________-______-_-___-__--_----__---_-_--_ 51-54 FIRuRE 1. Profile across the North Atlantic Ocean bottom along the line of the numbered core stations-____________________ xiv 2. Diagram showing the inferred relations of glacial marine and nonglacial sediments-___________________________ 8 3. Diagram showing three interpretations of the glacial marine zones in terms of stages and substages of the Pleisto- cene__ ___________-___-____-______________________-_-_____________________-__..___--__-_-__----_---- 10 4. Curve showing amplitude of solar radiation changes during the past 300,000 years. ___________________________ 12 5. Graph showing the CaO-C02 ratios of core samples in relation to the CaO-CO? ratio of pure calcite ______________ 17 6. Diagram showing distribution of volcanic ash shards in sediments.__________________________________________ 22 7. Dehydration curves of basaltic mud from core 10, a red clay from the Pacific Ocean, and typical halloysite and montmorillonite from clay deposits in the United States___--_____-_____________-___-_---------_-----_--_ 24 8. Relation of calculated original porosity of blue mud in core 3 to depth below top of core________-__--____.---_-_ 27 9. Sketch of the two halves of the top part of core 3 showing differential shrinkage_____-___-_-_----_--_-----_--- 28 10. Curves showing size distribution of organisms and mineral particles in blue mud, a gravelly foraminiferal marl, globigerina ooze, and clay.________--_-_______-__--___________-____--____--_-__---------___------_--- 29 11-21. Charts showing distribution and temperature significance of Foraminifera in the cores___-______--_----_--_-_- -- 36-45 in IV CONTEXTS TABLES TABLE 1. Geographic location, length of cores, and depth of the water from which they were taken______________________ xiv 2. Grain-size distribution in sample B-53 from core 5 and approximate composition______________-___--_-------_ 15 3. Distribution of magnesium carbonate within cores 3 to 13_ _____-_______-_-__________-__--__-_----.-_------- 19 4. Lime-magnesia ratios of the samples shown in table 3-_--__-___---_--__---_---_---___--------------------- 21 5. Grain and lump density and porosity of dried mud from cores 3 and 10, ard calculated original poroeity_____________ 27 6. Relative oxidation of iron in fresh and altered submarine basaltic glass-______________--______-___---_------_ 31 7. Analyses of mud from core 10 (sample W-15) and oceanic red clajTs______________________-_-____-__---_--_ 33 OUTLINE OF THE COMPLETE REPORT Foreword, by C. S. Piggot. General introduction, by W. H. Bradley. PART 1. Lithology and geologic interpretations, by M. N. Bramlette and W. H. Bradley. 2. Foraminifera, by Joseph A. Cushman and Lloyd G. Henbest. 3. Diatomaceae, by Kenreth E. Lohman. 4. Ostracoda, by Willis L. Tressler. 5. Mollusca, by Harald A. Render. 6. Echinodermata, by Austin H. Clark. 7. Miscellaneous fossils and significance of faunal distribution, by Lloyd G. Henbest. 8. Organic matter content, by Parker D. Trask, H. Whitman Patnode, Jesse LeRoy Stimson, and John R. Gay. 9. Selenium content and chemical analyses, by Glen Edgington and H. G. Byers. SUMMARY OF THE REPORT In May and June 1936 Dr. C. S. Piggot of the Geophysical zone has been identified. Other glacial marine deposits are Laboratory, Carnegie Institution of Washington, took a series of recognizable but their correlation is less certain. 11 deep-sea cores in the North Atlantic Ocean between the Three interpretations are offered as possible explanations of Newfoundland banks and the banks off the Irish coast. These the four glacial marine zones. The first is that each glacial cores were taken from the Western Union Telegraph Co.'s cable marine zone represents a distinct glacial stage of the Pleistocene ship Lord Kelvin with the explosive type of sounding device and that each zone of foraminiferal marl separating two gla.cial which Dr. Piggot designed. In the fall of that year he invited a marine zones represents an interglacial stage. This interpreta group of geologists of the United States Geological Survey to tion seems least probable of the three. The second interpretation study the cores and prepare a report. Biologists of the United is that the upper two glacial marine zones and the intervening States National Museum, the University of Buffalo, and chem sediment may correspond to the bipartite Wisconsin stage, ists of the United States Department of Agriculture cooperated whereas the lower two represent distinct glacial stages of the in the investigation and contributed to the report. Pleistocene separated from each other and from the zone repre The westernmost core of the series (No. 3)