INDEX

Africa Antarctica, separation, 918 Bottom water, 937 Agulhas Plateau, 949 Boundaries, criteria used to locate, 678 Albian foraminifera assemblages, 750 Boundary, biostratigraphic, 677 Albian-Cenomanian foraminifera, 747 foraminifera, Amphipyndax enesseffi Zone, 774 Miocene/Pliocene, 678 Amsterdam-St. Paul volcanic complex, 924 Oligocene/Miocene, 678 Angiosperms, 816 Pleistocene/Holocene, 680 Angular unconformity, 283, 288 Pliocene/Miocene, 687 Antarctic Bottom Water, 918 Pliocene/Quaternary, 679 Antarctica, separation of Africa, 918 Quaternary/Pliocene, 677, 687 Argon, nonradiogenic, 514 Brachiopod, 167 Argon analyses, 513 Broken Ridge, 8, 9, 233, 243, 281, 288, 359, 370, 418, Artostrobiom urna Zone, 772, 774, 775 925, 950 Aseismic ridges, 571, 910 Broken Ridge-Naturaliste Plateau, 7 Australian continental margin, 419 Bryozoans, 166, 167 Australian plate, 233 Calcareous nannoplankton, Site 251, 84 Authigenic garnet, 80, 85, 593, 594, 915 Calcispheres, 335, 747 Basalt, 80, 161, 162, 238, 301, 329, 331, 336, 466 Campanian-lower Eocene unconformity, 619 classification of tholeiites, 480 Carbon emmission spectrography, 541 criteria for recognizing altered, 472 Carbon-carbonate analysis, 16 crystallization differentiation, 481 Carbonate compensation depth, 140, 306, 336, 419, 950 electrical resistivity of, 505 Carlsberg Ridge, Central Indian Ridge, spreading on, grain-size range, 533 913 hematite in, 533 Celadonite,471 normative compositions, 477 Cenozoic species, nannoplankton, 619 ocean ridge, 484 Central Indian Basin, 418 olivine, 28, 235, 299, 329, 478 Ceratolithus tricorniculatus Zone, 623 petrography of, 466 Chemical analysis, authigenic, garnet, 594 phase chemistry, 484 Chemical analysis of pyroclastics, 560 plagioclase feldspars in, 485 Chemistry of basalts, 472 porphyritic, 471 Chert, 745 pyroxenes in, 484 Circumpolar current, 7, 9, 135, 140, 359, 929 rare-earth elements in, 569 Classification of pyroclastics, 553 sill, 466 tholeiites, 480 Site 250, 487, 914 Climatic shifts, 613 Site 251, 489, 915 Conglomerates, 237 Site 253, 489 Coniacian/Santonian foraminifera, 750 Site 254, 489 Coniacian/Santonian boundary, 750 Site 256, 489 Contamination, foraminifera, 677 Site 257, 466, 489 Corals, 167 thermal conductivity, 454 Cretaceous, nannoplankton, 669 thermally unstable state of, 529 Paleogene, nannoplankton, 669, 670 trace elements in, 483 sedimentation, 938 xenoliths, 470 systematics, foraminifera, 751 Basalt flows, graded, 470 Cretaceous magnetic lineations, 951 Basalt-sediment contact, 467 Cretaceous zonation, Radiolaria, 773 Basaltic flows, 418 Cretaceous/Tertiary boundary, 32 Basaltic terrain, 244 Crinoids, 166, 167, 745 Basis for age determination, Crozet Basin, 135, 140, 418, 913, 915 foraminifera, 13 Crustal ages, 9, 34 nannoplankton, 13 Wharton Basin sites, 930 Beach gravels, 929 Crystallization differentiation, basalt, 481 Bengal Fan, 919 Crystallization fractionation, 489 Biogenic ooze, 235 Current, Bottom, 23, 34, 140, 914 Bottom current, 23, 140, 914 Darling Fault Zone, 947 Bottom current circulation, 34, 918 Datum levels, 677

1123 Davie Ridge, 949 Site 255, 287, 690 Deccan traps, 949 Site 256, 304, 695 Detrital clay, 299, 329 Site 257, 335, 695 Detrital sediments, 914 Site 258, 368, 695 Deuteric oxidation, 533 Turonian, 750 Diamantina Fracture Zone, 359, 925 upper Pliocene, 679 Diamictites, 237, 244, 553 Zone N21, 84, 687 Diatoms, 671 Zone N20, 84 Dictyomitra veneta Zone, 772, 773, 774, 775 Zone N19, 84 Differentiation of magma, 489 Zone N16-N18, 681 Direct-reading spectrography, 541 Zone N4-N8, 33, 681 Discoaster asymmetricus Zone, 623 Zone P21, 166 barbadiensis Zone, 670 Zone P18, 166 druggi Zone, 623 Framboidal pyrite, 603, 604 exilis Zone, 623, 625 Garnet, authigenic, 80, 85, 593, 594 quinqueramus Zone, 623 Gartnerago obliquus Zone, 626, 635, 672 saipanemsis Subzone, 167, 670 Gastropods, 241 tani nodifer, 167 Geochemical measurements, Disconformities, 34, 914 Site 250, 29 Dissolution effects, 85 Site 251, 81 Dissolution facies, 7, 9, 930, 932, 934 Site 252, 138 Dissolved organic carbon, 615 Site 253, 163 Distribution of sediments, Indian Ocean, 7 Site 254, 239 Dolomite, 28 Site 255, 285 Drag folding, 922 Site 256, 303 Drake passage, 950 Site 257, 332 Drilling mud usage, 573 Site 258, 365 Ebridians, 671 Geochemistry, 542 Echinoids, 167 Geochemistry, rare-earth element concentrations in Eiffelithus turriseiffeli Zone, 306, 625, 633 pyroclastics, 563 Electrical resistivity of basalt, 505 Geochemistry of pyroclastics, 560 Endiopsode field, 484 Geochemistry of basalt, 567, 569 Environment of deposition, 617 Geochemistry of sediments, 542, 547 Fauna, shallow-water, 168 Geophysical measurements, 417 Fish debris, stratigraphic results, 910 Geothermal measurements, 451 system of descriptors, 827 sediment temperatures, 456 Fission track method, 515 Site 251, 456 Foraminifera, Site 253, 456 Albian-Cenomanian, 747, 750 Site 254, 458 basis for age determination, 13 Site 256, 460 Coniacian-Santonian, 750 Site 257, 461 contamination, 677 Gephyrocapsa oceanica Zone, 623 Cretaceous, systematics, 751 Gingin chalk, 626, 633, 636, 751 early Miocene, 678 Glass, fresh, 470 Globigerinatheka semiinvoluta Zone, 167 Globigerinatheka semiinvoluta Zone, 167 larger, 167 Gondwanaland, 7, 9, 281, 295, 327, 359, 910, 918, 929, lower Pliocene, 678 945 method of preparation, 675 Graded basalt flows, 470 middle Miocene, 678 Grain-size analyses, 15 middle Miocene/upper Miocene Boundary, 678 Grain-size range, basalt, 533 middle Pliocene, 679 Gypsum, 605 Miocene/Pliocene boundary, 241, 678 Harmonic mean thermal conductivity, 454 Oligocene marker species, 678 Hematite in basalt, 533 Pleistocene/Holocene, boundary, 687 as an alteration product of basalt, 507 Pliocene/Quaternary, boundary, 679 Hiatus, Quaternary, 680 Late Cretaceous, 932 Quaternary/Pliocene boundary, 241, 687 Oligocene, 935 Site 250, 32, 680 formation in the deep sea, model for, 937 Site 251, 83, 681 in the Eastern Indian Ocean, 933 Site 252, 687 High-temperature oxidation, 529 Site 253, 166, 687 Holocene/Pleistocene boundary, 695 Site 254, 241, 690 Hydrogarnets, 597

1124 Indian Ocean, 910 Microscopic pyrite, 603 distribution of sediments, 7 Micula staurophora Zone, 626, 635 formation of, 910 Mid-latitudinal Neogene sequence, 83 oldest sediment, 7 Mid-Ocean Ridge, 7 sediment thickness distribution, 910 Middle Eocene sedimentation, 939 southwestern, 911 Middle Miocene foraminifera, 678 Indian Ocean Ridge, southeast branch, 417 Middle Miocene/upper Miocene boundary, fora- Indian plate, 233 minifera, 678 Indonesia, 947 Middle Pliocene, foraminifera, 679 Indus Cone, 950 Miocene, subdivision of the, 678 Inoceramus, 287, 745, 750, 751 Miocene/Oligocene boundary, 690 Intrabasalt hiatus, 930 Miocene/Pliocene boundary, foraminifera, 241, 678 Invertebrate fossils, 167 Molluscs, 166, 242 Investigator Fracture Zone, 932 Mozambique Basin, 21, 33, 466, 913, 914, 918 Iron postdepositional migration of, 563 Mozambique Plateau, 417 Iron-rich tholeiitic basalt, 570 Mudstone, 235 Isotope fractionation, 615 Nannoplankton, Kamptnerius magnificus Zone, 626, 635 basis for age determination, 13 Kerguelen Plateau, 281, 925, 950 Cenozoic species, 619 Lanthanium and samarium enrichment factors, 549 Cretaceous, 669 Lapilli, 161, 553 Mesozoic species, 620 Larger foraminifera, 167 Paleoenvironment, 670 Late Cretaceous hiatus, 932, 933 Paleogene, 669 Late Pliocene and Quaternary, paleoclimate, 743 preservation of, 622 Limestone, 745 Site 250, 33, 626, 669 Lithiophorite, 299 Site 251, 628, 669 Lithologic nomenclature, 14 Site 252, 628, 670 Lithology, 26, 78, 137 Site 253, 167, 628, 670 Lithology, site 253, 157 Site 254, 242, 632, 671 Site 254, 235 Site 255, 288, 632 Site 255, 283 Site 256, 306, 633, 671 Site 256, 299 Site 257, 634, 671 Site 257, 329 Site 258, 369, 635, 672 Site 258, 363 solution of, 670 Lithraphidites alatus Zone, 625, 635 taxonomy, 636 Lower Miocene/middle Miocene boundary, Nannoplankton zonation, foraminifera, 678 Ceratolithus tricorniculatus Zone, 623 Lower Pliocene foraminifera, 678 Discoaster asymmetricus Zone, 623 Lysocline, 34, 85, 305, 306 Discoaster barbadiensis Zone, 670 M sequence of magnetic anomalies, 932 Discoaster druggi Zone, 623 Macrofossil debris, 237 Discoaster exilis Zone, 623, 625 Macrofossils, 244 Discoaster quinqueramus Zone, 623 Madagascar Basin, 417 Discoaster saipanensis Subzone, 167, 670 Maghemite, 533 Discoaster tani nodifer Zone, 167 Magma, differentiation of, 489 Eiffellithus turriseiffeli Zone, 306, 625, 633 Magnetic anomalies, 520, 919 Gartnerago obliquum Zone, 626, 635, 672 Magnetic lineations, 945 Gephyrocapsa oceanica Zone, 623 Magnetic measurements, correlation of resistivity with Kamptnerius magnificus Zone, 626, 635 petrology, 507 Lithraphidites alatus Zone, 625, 635 Magnetic susceptibility, 517 Marthasterites furcatus Zone, 626, 635, 672 Major elements, 542 Mesozoic, 625 Manganese, postdepositional migration of, 563 Micula staurophora Zone, 335, 626, 635 Mantle plume, 549, 571 Prediscosphaera cretacea Zone, 625, 634, 672 Marker species foraminifera, Oligocene, 678 Reticulofenestra hillae Subzone, 670 Marthasterites furcatus Zone, 626, 635, 672 Reticulofenestra pseudoumbilica Zone, 623 Median destructive field, 519 Rhabdosphaera inflata Subzone, 671 Mesozoic species, nannoplankton, 620, 625 Sphenolithus heteromorphus Zone, 623 Method of preparation, foraminifera, 675 Triquetrorhabdulus carinatus Zone, 623 Methods, X-ray mineralogy, 573 Natal Basin, 417 Methods of resistivity measurements in basalt, 505 Natural remanent magnetization, 519 Methods of laboratory measurements, seismic velocity, Naturaliste Plateau, 8, 9, 281, 327, 359, 370, 419, 925, 509 950 Microcontinental fragments, 8 Nematath, 153

1125 Neogene sequence, mid-latitudinal, 83 pollen, 815 Neutron activation analysis, 548 spores, 815 Ninetyeast Ridge, 7, 8, 9, 153, 168, 233, 243, 281, 418, taxonomic notes, 816 521, 549, 910, 919 Tertiary microfloras, 816 aseismic ridges, 571 Pelecypods, 167,241,745 former mantle plume, 563 Perth Abyssal Plain, 419 mantle-plume activity, 571 Petrography of basalt, 466, 467, 470, 471 oceanic andesite, 570 Petrography of pyroclastics, 553 petrography of basalt, 470 Phase chemistry, basalt, 484 petrography of pyroclastics, 553 Phase splitting, 529 stratigraphy and geology of the, 920 Phormocyrtis striata striata Zone, 772 tectonic history, 920 Physical properties, 16, 83 tholeiitic basalt, 570 Picritic basalt, 470 Nonradiogenic argon, 514 Plagioclase feldspars in basalt, 485 Normative compositions, basalt, 477 Pleistocene/Holocene boundary, foraminifera, 680 North Australian Basin, 945 Pliocene, foraminifera 679 Ob Trench, 359, 418, 925 subdivision of the, 678 Ocean ridge basalt, 484 Pliocene/Miocene, boundary, foraminifera, 687 Oceanic andesite, 570 Pliocene/Miocene boundary, 690, 695 Oligocene, early Tertiary, Pliocene/Pleistocene boundary, 305 dissolution facies, 932 Pliocene/Quaternary boundary, 287, 679 hiatus, 933, 935 Polar wandering curve, 523, 527 marker species foraminifera, 678 Pollen, 241, 815 unconformities, 932 Porphyritic basalt, 471 Oligocene/Miocene, boundary, 678 Postdepositional migration of iron, 563 Olivine, basalt, 235, 299, 329 manganese, 563 Olivine-normative, basalt, 478 Potassium analyses, 513 Olivine-rich, basalt, 28 Potassium argon analytical data, 513 Ommatartus penultimus Zone, 139, 772 Prediscosphaera cretacea Zone, 625, 634, 672 Opaque minerals, 533 Preservation of, nannoplankton, 622 Operations, 23, 77, 135 Pyrite, early diagenetic, 606 Site 253, 155 nebuloids, 604 Site 254, 246 Pyroclastic sequence, 560 Site 255, 283 classification of, 553 Site 256, 299 geochemistry of, 560 Site 257, 327 Pyroxenes in basalt, 484 Site 258, 359 Quartz-normative basalt, 477 Organic carbon, 613, 615 Quaternary foraminifera, 680 Osborn Knoll, 919 Quaternary/Pliocene boundary, 166, 241, 368, 677, 687, Ostracods, 241, 242 690, 695 Oxidation, deuteric, 533 Radiolaria zonation, high-temperature, 529 Amphipyndax enesseffi Zone, 774 Pacific-Antarctic Ridge, 7, 910 Ariostrobiom uma Zone, 772, 774, 775 Palagonite, 595 Cretaceous zonation, 773 Paleoclimate, late Pliocene and Quaternary, 743 Dictyomitra veneta Zone, 772, 773, 774, 775 Paleoecological data, 617 Ommatartus penultimus Zone, 139, 772 Paleoecology, 751 RK2/RK3 boundary, 775 Paleoecology and paleogeography, palynomorphs, 816 RK4/RK5 boundary, 775 Paleoenvironment, nannoplankton, 670 RK6/RK7 boundary, 775 Paleolatitude, 519, 522, 523 Rotaforma hessi Zone, 775 Paleomagnetic data, 520, 950 Sethocapsa cetia Assemblage, 775 Paleontology, Sethocapsa trachyostraca assemblage, 775 Site 250, 32 Sphaerostylus lanceola Zone, 774 Site 251, 83 Staurosphaera septemporata Zone, 774, 775 Site 252, 139 Stichocapsa tenuis Zone, 774 Site 253, 166 Taxonomy, 775 Site 254, 241 Theocapsomma comys Zone, 774 Site 255, 285 Thyrsocyrtis bromia Zone, 772 Site 256, 304 Thyrsocyrtis tuberosa Zone, 772 Site 257, 335 Radiometric ages, 669 Site 258, 367 Random errors, 514 Palynomorphs, Rare-earth element concentrations in pyroclastics, 563 angiosperms, 816 in basalt, 569 paleoecology and paleogeography, 816 Rare-earth elements, 548 1126 Resistivity measurements in basalt, methods of, 505 sedimentation rates, 33 Reticulofenestra hillae Subzone, 670 subbottom reflections, 32 Reticulofenestra pseudoumbilica Zone, 623 Site 251, 75 Reversed polarity subzone, 521 alkalinity, 83 Reversed subzone, 522 authigenic garnet, 915 Rhabdosphaera inßata Subzone, 671 basalt, 489, 915 Rhodochrosite, 301 correlation of, seismic reflection profiles with drill- Rifting, Australia from Antarctica, 950 ing results, 83 RK2/RK3 boundary, 775 Cretaceous/Paleogene, nannoplankton, 669 RK4/RK5 boundary, 775 foraminifera, 83, 681 RK6/RK7 boundary, 775 geochemical measurements, 81 Rotaforma hessi Zone, 775 geochemistry of sediments, 542 Sandstone, 235 geothermal measurements, 456 Scoria, 161 microscopic pyrite, 603 Sea-floor spreading, 945, 950 nannoplankton, 84, 628 Secular variation, 522 paleontology, 83 Sediment temperatures, 456 pH, 82 Sediment-basalt contact, 471 Radiolaria, 771 Sedimentation, salinity, 82 Cretaceous, 938 petrography of basalt, 467 early Oligocene, 940 Site 252, 135 middle Eocene, 939 correlation of seismic reflection profile with drill- present-day, 940 ing results, 139 Sedimentation rate, 85, 140, -243, 699 Cretaceous/Paleogene, nannoplankton, 670 Sedimentation rates, Crozet Basin, 915 Site 250, 33 foraminifera, 687 Site 253, 167 geochemical measurements, 138 Site 254, 243 geochemistry of sediments, 542 Site 255, 288 nannoplankton, 628 Site 256, 306 paleontology, 139 Site 257, 335 paleontology, 139 Site 258, 370 physical properties, 139 Sedimentation through time, 937 Radiolaria, 772, 918 Seismic velocity, methods of laboratory measurements, radiolarian clay, 915 509 Site 253, 153, 919 Seismic velocity of ocean floor rock, 509 alkalinity, 163 Separation of Africa and Antarctica, 918 basalt, 489 Sethocapsa cetia Assemblage, 775 chemical analysis of pyroclastics, 560 Sethocapsa trachyostraca Assemblage, 775 correlation of seismic reflection profile with drill- Seychelles Bank, 950 ing results, 164 Shallow-water littoral environment, 244 Cretaceous/Paleogene, nannoplankton, 670 Shallow-water, fauna, 168 foraminifera, 166, 687 Shock remanent magnetization, 520 geochemical measurements, 163 Siderate nodules, 28 geochemistry of pyroclastics, 560 Silicoflagellates, 671 geochemistry of basalts, 567 Silicification, 745 geochemistry of sediments, 542 Sill, basalt, 466 geothermal measurements, 456 Sinking curve, 910 lithology, 157 Site 250 nannoplankton, 167, 628 alkalinity, 30 operations, 155 basalt, 487, 914 paleoclimate, late Pliocene and Quaternary, 743 detrital sediments, 914 paleontology, 166 disconformity, 914 petrography of basalt, 470 foraminifera, 32, 680 petrography of pyroclastics, 553 geochemical measurements, 29 />H, 163 geochemistry of sediments, 542 physical properties, 163 nannoplankton, 33, 626, 669 pyroclastic sequence, 560 paleontology, 32 Radiolaria zonation, 772 petrography of basalt, 466 salinity, 163 pH, 30 sedimentation rates, 167 physical properties, 31 Site 254, 233, 920 Radiolaria, 771 alkalinity, 239 salinity, 29 basalt, 489

1127 correlation of seismic profile with drill- foraminifera, 368, 695 ing results, 241 geochemical measurements, 365 foraminifera, 241, 690 geochemistry of sediments, 547 geochemical measurements, 239 lithology, 363 geochemistry of basalt, 569 nannoplankton, 369, 635, 672 geochemistry of sediments, 542 operations, 359 geothermal measurements, 458 paleontology, 367 lithology, 235 pH, 365 molluscs, 242 physical properties, 365 nannoplankton, 242, 632, 671 Radiolaria, 772 operations, 235 sedimentation rates, 370 ostracods, 242 Solution of nannoplankton, 670 paleontology, 241 Somali Basin, 949 petrography of basalt, 470 Somali Coast, 949 pH, 239 South Atlantic Ocean, 947 physical properties, 239 Southeast Branch, Indian Ocean Ridge, 7, 135, 140,417, Radiolaria, 772 910, 913, 929, 950 salinity, 239 Southwest Branch, Indian Ocean Ridge, 7, 8, 9, 75, 85, sedimentation rate, 243 40, 135, 911, 918, 947 Site 255, 281 petrography of basalt, 467 broken ridge, 925 spreading rate and age of, 913 correlation of seismic reflection profile with drill- Spectrography, ing results, 285 carbon emmission, 541 foraminifera, 287, 690 direct-reading, 541 geochemical measurements, 285 Spessartine, 593 geochemistry of sediments, 547 Sphaerostylus lanceola Zone, 774 lithology, 283 Sphenolithus heteromorphus Zone, 623 nannoplankton, 288, 632 Spores, 815 operations, 283 Spreading rate, 85, 918 paleontology, 285 and the age of the southwest branch, 913 physical properties, 285 Stable carbon isotope, 614 Radiolaria, 772 Staurosphaera septemporata Zone, 774, 775 sedimentation rates, 288 Stichocapsa tenuis Zone, 774 uplift, 288 Stratigraphic results, fish debris, 910 Site 256, 295, 930 Stratigraphy and geology of the Ninetyeast Ridge, 920 basalt, 489 Stratigraphy and sedimentation Wharton Basin, 930 correlation of seismic reflection profile with drill- Subbottom reflections, 32 ing results, 304 Subdivision of the, Miocene, 678 detrital clay, 299 Pliocene, 678 foraminifera, 304, 695 Submarine basalts, 533 geochemical measurements, 303, 460 Surface water temperatures, 613 geochemistry of sediments, 547 Survey data, 13 lithology, 299 System of descriptors, fish debris, 827 nannoplankton, 306, 633, 671 Systematic errors, 514 operations, 299 Systematic paleontology, 701 paleontology, 304 Systematics, foraminifera, Cretaceous, 751 physical properties, 304 Taxonomy, nannoplankton, 636 Radiolaria, 772 palynomorphs, 816 sedimentation rates, 306 radiolaria zonation, 775 Wharton Basin petrography of basalt, 470 Tectonic history, Ninetyeast Ridge, 920 Site 257, 327, 930 Terrestrial carbon, 613 alkalinity, 333 Tertiary microfloras, 816 basalt, 466, 489 Theocapsomma comys Zone, 774 calcispheres, 335 Theocotyle cryptocephala cryptocephala Zone, 772 foraminifera, 335, 695 Thermal conductivity, basalt, 454 geochemical measurements, 332, 461 harmonic mean, 454 lithology, 329 Thermal conductivity measurements, 452 nannoplankton, 634, 671 Thermally unstable state of basalt, 529 operations, 327 Tholeiites, classification of, 480 paleontology, 335 Thoeiitic basalt, Ninetyeast Ridge, 570 petrography of basalt, 471 Thyrsocrytis bromia Zone, 772 pH, 333 Thyrsocyrtis tuberosa Zone, 772 physical properties, 333 Titano magnetite, 533 Radiolaria, 772 Trace elements, 542 sedimentation rates, 335 enriched, 542 Site 258, 359 in basalt, 483 alkalinity, 365 Transform fault, 153 correlation of seismic reflection profile and drill- Transparent sediment, 418 ing results, 367 Triquetrorhabdulus carinatus Zone, 623

1128 Turonian foraminifera, 750 crustal ages, 930 Unconformities, 9, 932, 934 oldest sediment in, 930 angular, 283, 288 petrography of basalt, 470, 471 Campanian/lower Eocene, 619 stratigraphy and sedimentation, 930 dissolution facies, 7 X-ray diffraction methods, 16 Oligocene/early Tertiary, 932 X-ray mineralogy methods, 573 Uplift, site 255, 288 Xenoliths, 470 Upper Cretaceous, Western Australia, 750 Yama Fracture Zone, 418 Upper Miocene foraminifera, 678 Zambezi Fan, 918 Upper Pliocene foraminifera, 679 Zambezi Canyon, 23, 913 Virtual geomagnetic pole, 523 Zonal schemes, 677 Viscous remanent magnetization, 519 Zone N21, 84, 687 Vitric ashes, 553 Zone N20, 84 Volcanic ash, 160, 161 Zone N19, 84 Wallaby Plateaus, 295 Zone N16-N18, 681 Western Indian Ocean, 932 Zone N4-N8, 33, 681 Wharton Basin, 295, 306, 327, 335, 418, 419, 919, 945, Zone P18, 166 947

1129