746 INDEX pollutants (continued] organic contaminants 2:23 trace elements abundance 2:22* bioavailability 2:21 occurrence 2:21 speciation 2:21, 2:22* toxicity 2:22* persistent organic pollutants 2:23 polycyclic aromatic hydrocarbons (PAHs) 2:23 polymaths 1:433-434 polymolybdates 3:551, 3:552* Polystrata 2:430f Polyzoa See bryozoans (Bryozoa) Pomerania 2:154f Pontides of Turkey 5:458f, 5:458-459 Poosa, S 5:266t Popelogan-Victoria arc 4:82f, 4:87, 4:87f, 4:89 Popigai impact structure, Siberia 5:467f, 5:468 Popp, Georg 2:261 Parana oeningensis 2:420f porifera (Porifera) 2:408-417 anatomy 2:408, 2:409f biogenic silica 5:52 Cambrian 2:408-417, 4:171 Carboniferous 4:212 classification Archaeocyatha 2:408, 2:416, 2:416f Calcarea 2:408, 2:412, 2:414f chaetetids 2:413, 2:416f Demospongea 2:408, 2:409, 2:412f general discussion 2:408 Heteractinida 2:408, 2:413, 2:415f Hexactinellida 2:408, 2:411, 2:413f, 2:414f Sclerospongiae 2:408, 2:413, 2:415f, 2:416f stromatoporoids 2:413, 2:415f Cretaceous-Tertiary (K-T) boundary 3:379, 3:380f environmental settings 2:408 hypercalcified sponges 2:412 Jurassic 3:356 megascleres 2:408, 2:410f microscleres 2:408, 2:411 f nodular cherts 5:5 7f spicules 2:408, 2:410/", 2:411f,5:57f structural grades 2:409f Porites 3:526f, 4:506f, 4:568f, 4:569f porosity chalk 3:87, 5:48-49, 5:49f diagenetic processes 1:393 dolomite (CaMg(CO3)2) 4:234f, 4:236f, 5:83, 5:88f evaporites 1:5 52t gravity measurements 1:99, 1:99f hydrothermal circulation 5:367, S:368f lava, flows 4:454 limestones 4:234f, 5:107-108 petroleum emplacement 5:145, 5:148, 5:149f petroleum reservoirs 4:232, 4:233f, 4:234f, 4:311, 4:317f rock properties 1:5491, 1:552*, l:566f, 1:566-567, 1:5 67t sand 5:141f, 5:145, 5:146f, 5:147f9 5:149, 5:149f,5:150f sandstones 4:232, 4:233f secondary porosity 5:145, 5:147f sedimentary rocks 4:452, 5:25 porphyrins 4:251/j 4:257 porter 3:80 Portlock, J E 3:476 Portugal 2:75, 2:77f, 3:352*, 5:506f Posidonia Shale Formation, Germany 3:310t, 3:311, 4:384f post-depositional sedimentary structures 4:602-611 climatically induced structures desiccation 4:609, 4:609f evaporite pseudomorphs 4:610,4:61 Of periglacial deformation 4:610 raindrop impressions 4:610 concretions 4:610f, 4:611, 4:611f deforming forces burial alteration processes 4:604 density inversions 4:604, 4:605f down-slope gravitational forces 4:603-604, 4:605f glaciation 4:604 liquefaction 1:525-534,4:604,4:605f, 4:606 soft-sediment deformation processes deforming forces 4:603, 4:605f general discussion 4:602 shear strength loss 4:603, 4:605f soft-sediment deformation structures convolute lamination 4:604, 4:606f descriptions 4:605f dish and pillar structures 4:606, 4:607f extruded sheets 4:607 general discussion 4:604 load casts 4:604, 4:605f mud diapirs 4:607, 4:608f overturned cross-bedding 4:606, 4:606f pseudonodules 4:604 sand injection structures 4:607 sand volcanoes 4:607, 4:608f sedimentary growth faults 4:608, 4:609f slumps and slides 4:607 potash deposits 5:94 potassium (K) brewing process 3:79, 3:80t carbonatites 3:223* crustal composition 5:174* glauconite 3:542* hydrothermal fluids 3:629* kimberlites 3:248t lava/lava flows 3:224f mineral analysis 1:105* obsidian 3:269* oceanic manganese nodular deposits 5:114* potash 1:43 8t radiometric dating absolute dating techniques 1:88t Carboniferous stratigraphy 4:202f geoarchaeology 3:20 geological time-scale 5:518 glauconite 3:547 sedimentary rocks 5:69, 5:146, 5:147f Venus 5:246*, 5:247* vine nourishment 3:88 Potato Blight 2:153 Potiguar basin l:325f, l:326f, 1:327f pottsite (HPbBi(VO4)2-2H2O) 3:589t Povarennykh, Alexander 5:121 powellite (CaMo04) 3:551, 3:552* Powell,] W 3:181-182 Pozary Formation 4:189 Pragian stage Appalachians 4:87f background information 4:194 biodiversity 4:197, 4:199f extinction events 4:197f Global Standard Stratotype Sections and Points (GSSPs) 5:51 If insects 4:195-196 International Stratigraphic Chart (ICS) 5:517f marine environments 4:197f palaeoclimate 4:196f vegetation 4:195 Pranhita-Godavari Basin 3:142-147, 3:146f praseodymium (Pr) 3:223*, 3:224/", 3:242f prasinophytes 3:420, 3:424 Pratt, John Henry 1:98, 3:183 Pratt-Welker chain 3:315f, 3:316*, 4:479 praying mantises 2:297f, 2:300* prebiotic organic molecules 4:127 Precambrian acritarchs 3:418-428 applications 3:427 biostratigraphy 3:425 classification 3:422, 3:423f clusters 3:420 colour changes 3:418-419, 3:419f early Neoproterozoic 4:358-359 extraction methods 3:473 late Neoproterozoic 4:360, 4:361f Mesoproterozoic 4:356f, 4:357 middle Neoproterozoic 4:360 morphology excystment openings 3:420, 3:422f flanges 3:419f, 3:420 general discussion 3:419 microphotographs 3:421f processes 3:419f, 3:420, 3:422f wall types 3:420 occurrence 3:418 palaeoenvironmental distribution 3:426, 3:426f, 3:427f Palaeoproterozoic 4:357 palaeotemperatures 3:419, 3:427 palynology 3:418, 3:468, 3:469f