Contents
List of Contributors
Preface
1 Origin of the Atmosphere: History of the Release of Volatiles from the Solid Earth
I. Introduction
II. Secondary Origin of the Atmosphere
III. Evidence for Early Degassing
IV. Evidence for Continuing Release of Volatiles from the Upper Mantle
V. Degassing and Recycling
VI. Conclusion
2 Early Precambrian Weathering and Sedimentation: An Impressionistic View
I. Temperatures of the Early Precambrian
II. Weathering at 4.3 Billion Years before the Present
III. Sedimentation at 4.3 Billion Years before the Present
3 Very Old ( > 100 Million Years) Rocks in North America
4 Three Arguments for Continual Evolution of Sial throughout Geologic Time
I. Introduction
II. Proterozoic Shields
III. Phanerozoic Continental Growth
IV. Composition of Graywackes
5 Archean Geology and Evidence of Ancient Life in the Slave Structural Province, Canada
I. Yellowknife-Hearne Lake Area
II. Nature of the Archean Crust in the Slave Province
III. The Extent of the Archean Record in the Slave Province
IV. Evidence of Ancient Life in the Archean of the Slave Province
6 Carbon Contents of Early Precambrian Rocks
7 Condensed Phosphates from Abiotic Systems in Nature
I. Introduction
II. The Formation of Condensed Phosphates
III. Examples of the Formation of Condensed Phosphates
IV. The Preparation of P4Oi0
V. The Removal of M2 0 from Orthophosphate
VI. The Removal of Water of Constitution
VII. Oxygen Substitution Reaction
VIII. The Decomposition of Salts of Lower Oxides
IX. Condensed Phosphate Minerals
X. Conclusion
8 Hydrocarbons and Fatty Acids in Oil Shale of Permian Irati Formation, Brazil
I. Introduction
II. Experimental
III. Results
IV. Discussion
9 The Stable Isotopes of Hydrogen in Precambrian Organic Matter
I. Introduction
II. Experimental
III. Discussion
10 Evolution of the Terrestrial Oxygen Budget
I. Introduction
II. Geochemical Carbon Cycle and Terrestrial Oxygen Budget
III. Terrestrial 13C Mass Balance
IV. Stationary Sedimentary Mass and Evolution of Photosynthetic Oxygen
V. Paleoenvironmental Implications of the Model
11 Evidences of Archean Life
I. Chemical Evidence
II. Morphological Evidence
12 Earliest Evidence of Fossil Eucaryotes
13 Paleobiology of Stromatolites
I. Introduction
II. The Stromatolites
III. Stromatolite Biostratigraphy
IV. Paleobiology of Stromatolites
V. Gunflint Stromatolites
VI. Conclusions
14 Natural Mechanisms of Protection of a Blue-Green Alga against Ultraviolet Light
I. Introduction
II. Materials and Methods
15 Kakabekia, a Review of Its Physiological and Environmental Features and Their Relation to Its Possible Ancient Affinities
I. Material and Methods
II. Results and Discussion
16 A Discussion of Biogenicity Criteria in a Geological Context with Examples from a Very Old Greenstone Belt, a Late Precambrian Deformed Zone, and Tectonized Phanerozoic Rocks
17 Synthetic Organic Microstructures as Model Systems for Early Protobionts
I. Synthesis of Organic Microstructures
II. Morphology by Light Microscopy
III. Morphology by Transmission Electron Microscopy
IV. Chemical Studies
V. Catalytic Properties
VI. Kinetics of Synthesis
VII. Discussion
18 Comparison of Laboratory Silicified Blue-Green Algae with Precambrian Microorganisms
19 Eoastrion and the Metallogenium Problem
20 Evolution of Mitosis and the Late Appearance of Metazoa, Metaphyta, and Fungi
21 Iron-Sulfur Proteins and Superoxide Dismutases in the Evolution of Photosynthetic Bacteria and Algae
I. The Iron-Sulfur Proteins
II. Superoxide Dismutases
22 Low Oxygen Levels and the Pabnitoyl CoA Desaturase of Yeast: Relation to Primitive Biological Evolution
Subject Index