MESOZOIC/Triassic 351 transpressional tectonics Deformation of the crust by a combination of strike-slip (horizontal) motion and oblique compression trough An elongate depression in the crust with gently sloping borders xeromorphic scale-leaved conifers A group of conifers with thick, scaly leaves that retain water and thus allow the plants to live in relatively dry climates See Also Figure Dinosaurs appeared during the Triassic These m long skeletons of the Late Triassic theropod Coelophysis are from Ghost Ranch in northern New Mexico the overall Late Triassic lowering of the sea, which reduced the epicontinental seaways in which most of the marine reptiles lived Glossary compressional tectonics Deformation of the crust through compression (pushing together) cycadophytes A group of gymnosperm plants with compound leaves, including the cycads diapsids The lizard-like and ruling reptiles, including lizards, snakes, crocodiles, and dinosaurs extensional tectonism Deformation of the crust through extension (pulling apart) fore-arc The region between an island arc and an oceanic trench foreland The region in front of a deformed area of the crust freeboard The difference between mean sea-level and mean continental altitude graben A block of crust dropped down along faults relative to blocks on either side gymnosperm A vascular plant with seeds that are not covered by an ovary, such as conifers mesophytic The time of intermediate land plants, approximately equivalent to the Middle Triassic, Jurassic, and Cretaceous palaeophytic The time of ancient land plants, approximately equivalent to the Palaeozoic and Early Triassic pteridophyte A fern-like division of vascular plants that reproduce by spores retroarc foreland basin A zone of thickened sediment (basin) and extensional tectonism behind an island arc, floored by continental crust synapsids Mammal-like reptiles, including the ancestors of mammals Atmosphere Evolution Fossil Invertebrates: Molluscs Overview Mesozoic: Jurassic Microfossils: Conodonts Palaeoclimates Palaeozoic: Permian; End Permian Extinctions Pangaea Time Scale Further Reading Alberti F von (1834) Beitrag zu einer Monographie des Bunten Sandsteins, Muschelkalks und Keupers, und die Verbindung dieser Gebilde zu einer Formation Stuttgart: Cotta Benton MJ (ed.) (1993) The Fossil Record London: Chapman & Hall Callaway JM and Nicholls EL (eds.) (1997) Ancient Marine Reptiles San Diego: Academic Press ă sster Dobruskina IA (1994) Triassic floras of Eurasia O reichische Akademie Wissenschaften Schriftenreihe Erdwissen Kommission 10: 422 Embry AF (1988) Triassic sea level changes: Evidence from the Canadian Arctic archipelago SEPM Special Publication 42: 249 259 Embry AF (1997) Global sequence boundaries of the Trias sic and their identification in the western Canada sedi mentary basin Bulletin Canadian Petroleum Geology 45: 415 433 Erwin DH (1993) The Great Paleozoic Crisis: Life and Death in the Permian New York: Columbia University Press Kummel B (1979) Triassic In: Treatise on Invertebrate Paleontology, Part A, Introduction Fossilization (Taph onomy) Biogeography and Biostratigraphy, pp 351 389 Lawrence, KS: Geological Society of America and University of Kansas Press Lucas SG (1998) Global Triassic tetrapod biostratigraphy and biochronology Palaeogeography, Palaeoclimat ology, Palaeoecology 143: 347 384 Lucas SG (2000) The epicontinental Triassic, an overview Zentralblatt fuă r Geologie und Palaă ontologie Teil I 8: 475 496 Sherlock RL (1948) The Permo Triassic Formations London: Hutchinson’s Scientific and Technical Publ Tozer ET (1984) The Trias and its ammonoids: the evolu tion of a time scale Geological Survey Canada, Miscel laneous Report 35 Ottawa: Geological Survey Canada Yin H (ed.) (1996) The Palaeozoic Mesozoic Boundary Candidates of the Global Stratotype Section and Point of the Permian Triassic Boundary Wuhan, China: University of Geosciences Press Ziegler PA (1989) Evolution of Laurussia Dordrecht: Kluwer Academic Publ