The Canyon Group (Missourian Series) is a sequence of westward-dipping, genetically related carbonate and terrigenous clastic facies that crop out in a northeast-southwest belt across North-Central Texas. The section includes stratigraphic units between the base of the Palo Pinto Limestone and the top of the Home Creek Limestone. Surface and subsurface studies within thirteen counties indicate that terrigenous clastic rocks are principally component facies of high-constructive delta systems. The Perrin delta system repeatedly prograded westward and northwestward from source areas in the Ouachita Fold Belt. Algal-crinoid banks flanked the Perrin delta system on the northeast and southwest. A typical vertical deltaic sequence includes (upward) (a) organic rich, prodelta mudstone, devoid of invertebrate fossils; (b) thin, distal delta-front sandstone and mudstone, displaying graded beds, sole marks, and flow rolls; (c) thicker proximal delta-front sandstone, exhibiting contorted beds, flow rolls, and contemporaneous faults; (d) locally contorted distributary-mouth bar sandstone; and (e) distributary channel sandstone, containing abundant trough cross stratification and local clay-chip conglomerate. Thin, coal-bearing delta-plain deposits occur locally on top of deltaic sequences. All delta facies are rich in plant debris. During delta abandonment and destruction, shallow bay-lagoon environments developed. Destructional facies include bioturbated sandy mudstone, burrowed sandstone and thin, platy argillaceous limestone with abundant invertebrate fossils. Fossiliferous mudstone units grade upward into transgressive shelf carbonate units commonly composed of phylloid algal-crinoid biomicrudite and local intraclastic biosparite shoal facies. Shelf carbonate includes onlapping sheetlike deposits; thick elongate bank deposits, which stood above the sea floor with slight bathymetric relief; massive platform carbonate; and shelf edge reef-bank accumulations. The Henrietta fan-delta system, occurring exclusively in the subsurface of Montague, Clay, Wichita, Archer and Baylor counties, is composed of thick wedges of feldspathic sandstone and conglomerate that were deposited by high-gradient fluvial systems, which built southwestward into northern Texas from source areas in the Wichita-Arbuckle Mountains of southern Oklahoma. / text

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This dissertation presents the detailed results of investigations into the coastal geomorphological effects and sedimentation processes associated with a recent large tsunami event which took place on the 12th December 1992 in Flores, Indonesia, and the stratigraphical and sedimentological study of a widespread sand layer preserved in coastal sedimentary sequences along the eastern coast of Scotland representing a low-frequency, high-energy marine event, which took place at circa 7,000 radiocarbon years B.P. With modern alalogues, established in this dissertation, of both tsunami and storm surge sedimentary characteristics and sedimentation processes as the key, together with high-resolution sedimentological evidence obtained from the circa 7,000 radiocarbon years B. P. event, competing hypotheses of the likely causes of the marine flooding by either a tsunami or storm surge event are tested. It is concluded that the circa 7,000 B. P. marine flooding event was a tsunami, believed to have been generated by one of the world's largest submarine landslides in the Norwegian Sea - the Second Storegga Slide. The particle size composition of tsunami sediments is found to vary from well sorted to poorly sorted and is controlled by both the characteristics of the source sedement (local coastal sediments) and sedimentation processes associated with tsunami inundation. Tsunami sediments deposited on land are believed to form continuous and discontinuous sedimentary sheets ascending up to levels distinctively higher than contemporary sea levels and to contain a general landward-fining trend and multiple sets of grading (fining-upward) sequences, reflecting spatial changes in particle size composition. A conceptual model of coastal tsunami sedimentation is established including processes of seaward and landward sediment movements, episodic rapid deposition, sediment accumulation and erosion.