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A completely new Upper Cambrian formational nomenclature is proposed for the southern Rocky Mountains of Alberta. The formations designated as Upper Cambrian are: Corona, and Mount Synge, Dresbachian; Bison Creek, Franconian; and the Mistaya, Trempealeauan. Two additional formations are referred to the Middle Cambrian sequence immediately underlying the Upper Cambrian; the Chephren and the Waterfowl. These latter formations were previously included in the Arctomys formation considered to be Upper Cambrian in age. The lowest Lower Ordovician formation is designated as the Howse River formation. In addition to the above mentioned new formations, the Arctomys, Sullivan, Lyell, Mons, Bosworth, Paget, Sherbrooke, Tangle Ridge, and Sabine formations are discussed in detail. All are considered obsolete, except the Sabine formation, the use of which, it is recommended, be confined to the Canal Flats area, British Columbia. The limits of the Upper Cambrian series in Alberta are more precisely determined, and tentative correlation of the Upper Cambrian of Alberta, Montana, and British Columbia is outlined. Trilobite faunas from all the Upper Cambrian zones, except the Crepicephalus zone, are described and illustrated. The Cedaria zone faunas contain fifteen genera and eighteen species, among them Bolaspidelia wellsvillensis, Nixonella montanensis, several species of Arapahoia and Cedarina, and Kingstonia mucro. Abundant topotype material of K. mucro has made redefinition of this species possible. The Aphelaspis zone is recognized by the discovery of Aphelaspis walcotti, and one questionable species of Aphelaspis. The Franconian zones are represented by Irvingella major, Taenicephalus shumardi, Parabolinoides cordiIlerensis, Maustonia nasota, KendalIina eryon, Ptychaspis striata, Prosaukia lonqicornis and Prosaukia curvicostata, to mention only the more important index species. The Saukia zone of the Trempealeauan is represented by species of Eurekia, StenopiIus, Bynumiella. Hardyia and IlIaenurus. / Science, Faculty of / Earth, Ocean and Atmospheric Sciences, Department of / Graduate

Archaeocyatha from the Lower Cambrian of Wolf Lake and Quiet Lake areas in the Yukon Territory are described and illustrated. The fossils occur in carbonate rocks and are well preserved. Much of the necessary structural detail of the fossils is clearly observed in thin-sections and on polished surfaces of the specimens. The collection contains twenty-three species, twelve of which are new species. The new species described are: Ajacicyathus yukonensis, Coscinocyathus multiporus. Coseinocyathus cassiariensis, Coscinocyathus inequivallug, Coscinocyathus serratus, Coscinocyathus veronicus, Coscinocyathus tubicornus, Carinacyathus perforatus, Pyenoidocyathus solidus, Loculicyathus elliptieus, Metacoscinus poolensis, and Claruscyathus ketzaensis. The genera Carinacyathus and Loculicyathus are reported for the first time in North America. The Yukon fauna is dominated by Coscinocyathidae and Pycnoidocyathidae, showing close relationship to faunae in the Cordilleran region of British Columbia. It also shows relationship to Siberian and Australian faunae. This fauna is very different from the archaeocyathid assemblages in Nevada and California, where the dominant forms are Ethmophyllidae and Ajacicyathiclae. Arehaeocyatha have been instrumental in determining the age of rocks underlying a large area of the Yukon Territory. / Science, Faculty of / Earth, Ocean and Atmospheric Sciences, Department of / Graduate

Trilobites and other fossils from three measured sections in the Murray Range, Pine Pass map-area, British Columbia, are described and their zonal significance is discussed. Zones represented by fossil assemblages are the Upper Olen-ellus subzone (uppermost Lower Cambrian), the Ogygopsis klotzi and Tonkinella stephensis subzones of the Bathyuriscus-Elrathina zone (upper Middle Cambrian), the upper Conaspis zone and Ptychaspis subzone of the Ptychaspis-Prosaukia zone (Upper Cambrian, Franconian Stage), the Lower or Middle Saukia zone (Trempealeau-an Stage), and Zones A, B and D of the Lower Ordovician (Canadian Series). The lower Middle Cambrian, Dresbachian and lower Franconian zones, and the Lower Ordovician Zone C, appear to be missing. Early Cambrian assemblages show some affinities with faunas of the southern hemisphere (the archaeocyathid genera Sigmocya-thus, Syringocnema and Monocyathus) and eastern Canada and the United States (species of Bonnia, Kootenia, Paedeumias and Eo-ptychoparia). However, these affinities become weaker in Middle Cambrian and later assemblages, and all the present collections are predominantly Cordilleran in character. They are considered representative of the intermediate extracratonic biofacies realm as defined by Lochman-Balk and Wilson (1958). The sections provide a further example of the transition, well-known in other parts of the Canadian Cordillera, from Lower Cambrian argillaceous and arenaceous clastic rocks to more or less argillaceous limestone and dolomite of the Middle Cambrian and later Series. Throughout Cambrian and early Ordovi-cian time the original area represented by the present sections was covered by miogeosynclinal seas which progressively encroached upon the craton. This marine transgression was interrupted at times, and the comparatively local uplift of the Peace River Arch was responsible for extreme reduction in thickness of the Middle and Upper Cambrian portions of the early Palaeozoic section. / Science, Faculty of / Earth, Ocean and Atmospheric Sciences, Department of / Graduate

An exhaustive field study of the Cambrian stratigraphy of the northern Wasatch region indicates that in addition to the Blacksmith Fork section there are two complete and better exposed middle and upper sections. Several other good exposures of the lower Middle Cambrian section have been studied in detail. The Spence shale is found to be a member low in the Langston, not the basal member of the Ute. Relative ages of the Spence shale and Ptarmigania faunas have been determined. Other Cambrian faunal zones have been discovered and are discussed. Paleontologic evidence suggests that the Nounan formation is of Upper Cambrian (Cedaria) age. Laboratory and field evidence indicates the probable Lower Cambrian age of the Brigham formation.

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abstract: The Cambrian lattice corresponding to a Coxeter element c of An, denoted Camb(c), is the subposet of An induced by the c-sortable elements, and the m-eralized Cambrian lattice corresponding to c, denoted Cambm(c), is dened as a subposet of the braid group accompanied with the right weak ordering induced by the c-sortable elements under certain conditions. Both of these families generalize the well-studied Tamari lattice Tn rst introduced by D. Tamari in 1962. S. Fishel and L. Nelson enumerated the chains of maximum length of Tamari lattices. In this dissertation, I study the chains of maximum length of the Cambrian and m-eralized Cambrian lattices, precisely, I enumerate these chains in terms of other objects, and then nd formulas for the number of these chains for all m-eralized Cambrian lattices of A1, A2, A3, and A4. Furthermore, I give an alternative proof for the number of chains of maximum length of the Tamari lattice Tn, and provide conjectures and corollaries for the number of these chains for all m-eralized Cambrian lattices of A5. / Dissertation/Thesis / Doctoral Dissertation Mathematics 2017

of Mgr. Martin Valent doctoral thesis Hyoliths of the Barrandian Area The submitted Ph.D. thesis summarizes recent information on comparatively poorly known group of invertebrates - the hyoliths. The first part of the thesis is composed by six main chapters focussed in detail on various aspects of hyoliths; major characteristics and ecology of hyoliths, progress in systematic of hyoliths, principles of hyolith classification, stratigraphical and palaeogeographical distribution of hyoliths, hyoliths within the Bohemian Massif and morphology of hyoliths. Up-to-date information has been included in all chapters. New data were published in five author's papers on hyolith colour patterns, systematics of hyoliths, pattern of palaeogeographic distribution and palaeoecologic interactions between hyoliths and various elements of the Cambrian invertebrate fauna. Short appendage consists of the Czech-English-Chinese terminological dictionary, simplifying study of Chinese literature.

Numerous detailed geochemical studies of Ediacaran (~635 - 541 Ma) marine successions provide snapshots into the palaeoenvironmental redox conditions which accompanied examples of the earliest metazoans in the fossil record. Spatial heterogeneity with respect to palaeomarine redox is evident from reconstructions of geographically-widespread Ediacaran environments. This project provides new data of local-scale redox within a paleogeographic and sequence stratigraphic framework in order to explore the mechanisms which controlled water column redox variations and the potential impact on early macro-benthic ecosystems. Lower than present atmospheric and oceanic oxygen concentrations enabled some shallow marine settings to remain poised at iron reduction until well into the Cambrian and likely influenced regional-scale ecosystem structure and stability. Many basins had a shallow and highly dynamic chemocline above anoxic (ferruginous or euxinic) or low oxygen (manganous) waters. Regional differences in palaeoredox were likely controlled primarily by local detrital nutrient provision and organic matter remineralisation and the redox state of the global deep ocean was most likely similarly heterogeneous (but this remains uncertain). It is suggested that cratonic positioning and migration throughout the Ediacaran Period, in combination with gradually increasing dissolved oxygen loading, may have provided a long-term control on redox evolution through regulating circulation mechanisms in the Mirovian Ocean. Some unrestricted lower slope environments from mid-high latitudes benefited from sustained oxygenation via downwelling, whilst cratonic isolation or transit towards more equatorial positions stifled pervasive ventilation either through ineffective surface ocean mixing, Ekman-induced upwelling, elevated surface ocean productivity, or a combination of these processes. Co-preservation of largely-enigmatic fossil forms within sedimentary rocks of the late Ediacaran Nama Group of southern Namibia have allowed the four-dimensional reconstruction of local redox dynamics and associated biotic establishment. This has been made possible through collation of previously published fossil occurrence and geochemical information alongside new palaeoredox and palaeoproductivity estimates based on iron speciation, major element and carbonate-bound iodine data. This is further supplemented by the first detailed assessment of the paragenetic sequence and diagenetic relationships of carbonates which precipitated within the earliest metazoan reef framework. Skeletal invertebrate taxa in the Zaris Sub-Basin of the lower Nama Group (~550-547 Ma), grew above wave base where micritic carbonate sediment often shows evidence for early dolomitisation. Mid-ramp Cloudina reefs composed of open, highly porous structures formed multiple, successive assemblages. Thin layers of dolomitised sediment and dolomite cement terminate each assemblage. Reef cements show a paragenetic sequence from synsedimentary, early marine cement through to final burial, each of which were precipitated under dynamic redox conditions. These cements likely record a general shallow to deeper water transect, from oxic shallow waters to low oxygen manganous waters and finally to oxic, shallow burial conditions. Transient incursions of upwelled, anoxic, ferruginous and dolomitising waters may have occurred during short-term, transgressive cycles, although the timing for this is poorly constrained. Such incursions may have terminated Ediacaran benthic communities that grew close to the chemocline. Viewed in its entirety, the palaeoredox record of the Nama Group reveals evidence for a pronounced shift in the depth of the ferruginous redoxcline from shallow to deeper levels in the water column through time, which was accompanied by a reduced frequency of anoxic incursions onto the shallow shelf. This transition approximately coincided with the first appearance and subsequent diversification of novel sediment bioturbators in the Lower Urusis Formation (~547-542 Ma). It is proposed that the observed coevolution of palaeoredox and ichnofossil diversity may directly relate to the impact of bioturbation on phosphorus retention. In this way, the diversification of burrowing forms effectively oxygenated the sediment column, prevented efficient P recycling to the water column and limited the detrimental impact of productivity-induced anoxia in the local environment. However, this hypothesis remains to be tested and would benefit from a focused study of palaeoproductivity employing targeted analyses of total organic carbon and sedimentary phosphorus speciation. It is further proposed that the persistent spatial separation of anoxic deep waters from habitable ecospace, implied by the fossil distribution of phylogenetically-enigmatic soft-bodied forms, qualitatively supports the inference that at least intermittently oxic conditions (at or above EH typical of ferrous iron oxidation) were a metabolic requirement of these organisms. Finally, four new sections of the late Ediacaran, deposited approximately time-equivalent to aforementioned sediments of the Nama Group, are described and preliminary geochemical data reported. These include two shallow marine carbonate-dominated sections of the southeast Siberian Craton which correspond to the Yudoma Formation and two sections of the Dengying and lower Zhujiaqing (and correlative) Formations deposited on the Yangtze Block, South China. Integrated proxy methods are able to distinguish palaeoredox heterogeneity between and within early animal ecosystems and test the influence of anoxia on ecosystem structure. The first and last appearances of Treptichnus pedum and Cloudina respectively, which globally bracket the boundary between the Ediacaran and Cambrian Periods, show no identifiable range overlap in any sections analysed in this study. This suggests that the first appearance of the organism responsible for characteristic T. pedum may have lived approximately contemporaneous in oxic habitable refuges of all regions in this study, regardless of the dominance of reducing conditions that persisted in coeval deeper environments in many areas.