Contents
Introduction .......................................... .
1
Origin and Morphology of Ocean Basins. . . . . . . . . . . .. 15
1.1 The Depth of the Sea. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
1.2 Endogenic Processes .. . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 16
1.3 Exogenic Processes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 20
1.4 Morphology of the Mid-Ocean Ridge. . . . . .. .. . . . . . . . .. 21
1.5 Morphology of the Trenches . . . . . . . . . . . . . . . . . . . . . . . .. 25
1.6 Fracture Zones and Plate Tectonics. . . . . . . . . . . . . . . . . . .. 28
1.7 Seamounts, Island Chains, and Hot Spots. . . . . . . . . . . . . .. 29
1.8 Evidence for Sea-Floor Spreading: the Magnetic Stripes. .. 32
1.9 Open Tasks and Questions. . . . . . . . . . . . . . . . . . . . . . . . . .. 36
2
Origin and Morphology of Ocean Margins.. . . . . .. . .. 41
2.1 General Features of Continental Margins . . . . . . . . . . . . . .. 41
2.2 Margins Are Sediment Traps. . . . . . . . . . . . . . . . . . . . . . . .. 44
2.3 Atlantic-Type (= Passive) Margins. . . . . . . . . . . . . . . . . . .. 45
2.4 Unsolved Questions in the Study of Passive Margins. . . .. 51
2.5 Pacific-Type (= Active) Margins. . ... .. .... .. . ... .. . .. 51
2.6 Shear Margins and Complex Margins. .. . . .. .. . . . . . . . .. 54
2.7 The Shelf Areas. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 55
2.8 The Shelf Break.. .. . . . . . . . . . . . . . . .. . . .. .. . . .. . . . .. 56
2.9 Continental Slope and Continental Rise. . . . . . . . . . . . . . .. 57
2.10 Submarine Canyons. . . .. . . . . . . . . . . .. . . .. .. . . . . . . . .. 60
2.11 Deep-Sea Fans . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 66
3
Sources and Composition of Marine Sediments. . . . . . .. 69
3.1 The Sediment Cycle. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 69
3.2 Sources of Sediment. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 69
3.2.1 River Input. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 69
3.2.2 Glacier Input. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 71
3.2.3 Input from Wind . . . . . . . . . . . . . . . . . . . . . . . . . . .. 71
Introduction .......................................... .
1
Origin and Morphology of Ocean Basins. . . . . . . . . . . .. 15
1.1 The Depth of the Sea. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
1.2 Endogenic Processes .. . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 16
1.3 Exogenic Processes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 20
1.4 Morphology of the Mid-Ocean Ridge. . . . . .. .. . . . . . . . .. 21
1.5 Morphology of the Trenches . . . . . . . . . . . . . . . . . . . . . . . .. 25
1.6 Fracture Zones and Plate Tectonics. . . . . . . . . . . . . . . . . . .. 28
1.7 Seamounts, Island Chains, and Hot Spots. . . . . . . . . . . . . .. 29
1.8 Evidence for Sea-Floor Spreading: the Magnetic Stripes. .. 32
1.9 Open Tasks and Questions. . . . . . . . . . . . . . . . . . . . . . . . . .. 36
2
Origin and Morphology of Ocean Margins.. . . . . .. . .. 41
2.1 General Features of Continental Margins . . . . . . . . . . . . . .. 41
2.2 Margins Are Sediment Traps. . . . . . . . . . . . . . . . . . . . . . . .. 44
2.3 Atlantic-Type (= Passive) Margins. . . . . . . . . . . . . . . . . . .. 45
2.4 Unsolved Questions in the Study of Passive Margins. . . .. 51
2.5 Pacific-Type (= Active) Margins. . ... .. .... .. . ... .. . .. 51
2.6 Shear Margins and Complex Margins. .. . . .. .. . . . . . . . .. 54
2.7 The Shelf Areas. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 55
2.8 The Shelf Break.. .. . . . . . . . . . . . . . . .. . . .. .. . . .. . . . .. 56
2.9 Continental Slope and Continental Rise. . . . . . . . . . . . . . .. 57
2.10 Submarine Canyons. . . .. . . . . . . . . . . .. . . .. .. . . . . . . . .. 60
2.11 Deep-Sea Fans . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 66
3
Sources and Composition of Marine Sediments. . . . . . .. 69
3.1 The Sediment Cycle. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 69
3.2 Sources of Sediment. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 69
3.2.1 River Input. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 69
3.2.2 Glacier Input. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 71
3.2.3 Input from Wind . . . . . . . . . . . . . . . . . . . . . . . . . . .. 71