Download or read book Stratigraphy Sedimentology and Biostratigraphy of the Ordovician Rocks of the Lake Simcoe Area South central Ontario written by Geological Association of Canada and published by Geological Association of Canada/Mineralogical Association of Canada, Waterloo 1994 Committee. This book was released on 1994 with total page 101 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Field Trip A4 Guidebook Stratigraphy Sedimentology and Biostratigraphy of the Ordovician Rocks of the Lake Simcoe Area South central Ontario written by Geological Association of Canada-Mineralogical Association of Canada. Joint Annual Meeting (1994 : Waterloo, ON) and published by . This book was released on 1994 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Stratigraphy Sedimentology and Biostratigraphy of the Ordovician Rocks of the Lake Simoce Area South central Ontario written by M. J. Melchin and published by . This book was released on 1994 with total page 101 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Stratigraphy Sedimentology and Biostratigraphy of Ordovician Rocks of the Peterborough Lake Simcoe Area of Southern Ontario written by Mario Coniglio and published by . This book was released on 1990 with total page 82 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Sedimentology and Paleocommunities of the Black River and Trenton Limestone Groups Ordovician Lake Simcoe Area Ontario written by Michael E. Brookfield and published by . This book was released on 1998 with total page 42 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Canadian Journal of Earth Sciences written by and published by . This book was released on 2007 with total page 628 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Global Synthesis of the Ordovician System Part 2 written by T. Servais and published by Geological Society of London Special Publications. This book was released on 2023-06-08 with total page 618 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Ordovician was one of the longest of the geological periods, characterized by major magmatic and tectonic activity, an immense biodiversification, swings in climate and sea levels, and the first Phanerozoic mass extinction. ‘A Global Synthesis of the Ordovician System’ is presented in two volumes in The Geological Society, Special Publications. Whereas the first volume (SP532) concentrates on general aspects and a synthesis of the Ordovician geology of Europe, this volume (SP533) includes reviews of Ordovician successions of most other parts of the world. The classic successions of the Ordovician basins of North America are presented, as well as those of China where several of the Ordovician Global Boundary Stratotype Sections and Points are defined. The volume also includes syntheses of the Ordovician geology of Africa, South America, most regions of Asia from the Near to the Far East along with Central Asia, as well as Australia, New Zealand and Antarctica.
Download or read book Ordovician Odyssey written by John Doyne Cooper and published by Pacific Section Society of Economic Paleontologists & Mineralogists. This book was released on 1995 with total page 526 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Northeastern Geology and Environmental Sciences written by and published by . This book was released on 2007 with total page 424 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Sedimentology Sequence Stratigraphy and Brachiopod Biostratigraphy of the Ordovician Mohawkian Decorah Formation Midcontinent USA written by Norlene René Emerson and published by . This book was released on 2015 with total page 490 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Ordovician (Mohawkian) Decorah Formation in the upper Mississippi Valley region is identified as a mixed siliciclastic-carbonate unit deposited between stratigraphic units that are dominated by carbonate lithologies. The Decorah was deposited within a vast epeiric sea during one of the largest episodes of marine flooding of the North American craton. Detailed sedimentology, stratigraphy, and brachiopod biostratigraphy has revealed that the Decorah Formation consists of one depositional sequence bounded by two regionally extensive discontinuities and contains a nested hierarchy of two high-frequency sequences and four cycle sets. The lowest cycle set consists of shale-rich facies that thicken (northwest) toward clastic source areas along the Transcontinental Arch during a time of high clastic influx and abundant freshwater runoff creating at times, a salinity-stratified water column and dysoxic conditions. The remaining three cycle sets consist of carbonate-rich facies that form a reciprocal wedge of sediment that thickens southeast and was deposited during relative flooding of the clastic source areas reducing the clastic sediment and freshwater supply. The carbonate-rich facies was deposited in more oxic conditions with carbonates showing down ramp progradation from south to north. Brachiopod biostratigraphy revealed that most species had ranges confined to the Decorah Formation and did not have ranges that crossed formation boundaries. Graphic correlation methods using brachiopod species first and last appearance data, as well as the stratigraphic positions of two k-bentonites, outlined changes in sediment accumulation rates from north to south as well as differences in rates between the two major lithofacies (shale vs. carbonate) of the Decorah. Multivariate Q-mode cluster analysis established two major clusters reflecting the shale- versus carbonate-rich lithofacies change. These results were interpreted to indicate that both biofacies and lithofacies patterns reflect a close link between environmental shifts and faunal change. Correlation of time equivalent rocks in eastern North America reveals large differences suggesting different water masses for the midcontinent and eastern North America. This interpretation suggests that the North America Ordovician epeiric sea was not necessarily a continuous sea but rather subtle topographic changes divided the flooded continent into different depositional areas with distinct physical, biological, and chemical signatures.
Download or read book Sedimentology and Sequence Stratigraphy of the Ordovician Black River and Lower Trenton Groups Lake Simcoe Area Ontario written by and published by . This book was released on 2001 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Subsurface Stratigraphy of Ordovician Rocks in Southwestern Ontario written by B. V. Sanford and published by Ottawa, Department of Mines and Technical Surveys, Canada. This book was released on 1961 with total page 68 pages. Available in PDF, EPUB and Kindle. Book excerpt: A geological report that covers the subsurface stratigraphy of Ordovician rocks in southwestern Ontario.
Download or read book Field Guidebook to the Stratigraphy Sedimentology and Paleontology of the Upper Ordovician Rocks in Southwestern Ohio written by Douglas L. Shrake and published by . This book was released on 1988 with total page 94 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Diagenesis of Middle Ordovician Rocks from the Lake Simcoe Area South central Ontario written by Laura Mancini and published by . This book was released on 2011 with total page 168 pages. Available in PDF, EPUB and Kindle. Book excerpt: Middle Ordovician carbonates in the Lake Simcoe area, south-central Ontario were examined to determine if: (1) The [delta]18O values of early-stage calcite cement in hardgrounds are useful proxies for Ordovician seawater [delta]18O values; (2) a regional hydrothermal event affected middle Ordovician strata in the Lake Simcoe area. Whole rock samples of middle Ordovician hardgrounds and immediately overlying limestones containing early calcite cement have [delta]13C values ranging from -1.7 to +2.9[per mille] (PDB) and [delta]18O values ranging from -6.9 to -2.9[per mille] (PDB). Hardground [delta]18O values and the similarity of the isotopic composition between the hardgrounds and overlying limestones are consistent with diagenetic alteration during shallow burial, which indicates the hardgrounds are not useful proxies. Late-stage calcite cements have [delta]13C values from -8.4 to +2.9[per mille] (PDB) and [delta]18O values from -11.4 to -6.0[per mille] (PDB). Late-stage microcrystalline dolomites have [delta]13C values from -3.9 to +0.4[per mille] and [delta]18O values from -10.7 to -7.6[per mille]. Late-stage saddle dolomites have [delta]13C values from -1.7 to 1.9[per mille] and [delta]18O values from -13.8 to -8.5[per mille]. The late-stage carbonate [delta]18O values are more negative than the early-stage carbonate [delta]18O values and are interpreted to reflect progressively deeper burial diagenesis. Four types of fluid inclusions were identified in late-stage calcite, saddle dolomite, barite, and quartz. Type 1 inclusions are aqueous liquid-rich with very consistent low to very low vapour-liquid ratios and are of primary, secondary pseudosecondary and indeterminate origins. Type 2 inclusions are aqueous liquid-only and are of primary and secondary origins. Type 3 inclusions are oil-bearing, liquid-rich with low to medium vapor-liquid ratios and are of secondary origin. Type 4 inclusions are vapour-only and are of indeterminate origin. The type 4 inclusions analyzed did not yield any microthermometric data suggesting they are empty cavities that have lost all their fluid. Fluid inclusions of primary, secondary and pseudosecondary origins in calcite, dolomite and quartz have overlapping homogenization temperatures ranging from 43 to 188°C. Fluid inclusions of indeterminate origin in calcite and barite have homogenization temperatures from 80 to greater than 200°C. Petrographic and microthermometric evidence indicates that fluid inclusion homogenization temperatures greater than 150°C most likely are caused by stretching or leaking; therefore, are discounted. Fluid inclusion types 1 and 2 represent two fluid inclusion assemblages (FIA) based on final ice melting temperatures. The high salinity (10 to 30 wt%CaCl2) inclusions in FIA 1 are of primary, secondary, pseudosecondary and indeterminate origin in calcite, dolomite, barite and quartz. Fluid inclusions in FIA 1 are interpreted as reflecting saline basin brines from which the host minerals precipitated during burial diagenesis. The low salinity (0 to 2.7 wt%CaCl2) inclusions in FIA 2 are of secondary and indeterminate origin in calcite. Fluid inclusions in FIA 2 may reflect a meteoric origin such as in a vadose or phreatic environment based on inclusions containing different phases and variable vapor-liquid ratios. Alternatively the low salinity inclusions may reflect alteration from an influx of meteoric fluids that migrated through basement faults and fractures during periods of uplift and erosion. Early and late-stage carbonates from this study precipitated from 18O-depleted pore fluids and/or at progressively higher temperatures accompanying deeper burial. The FIA 1 homogenization temperatures support burial diagenesis at 66 to 80°C if it is assumed the rocks were buried 2 km, the surface temperature was 20°C and the geothermal gradient was between 23 to 30°C/km. An alternative interpretation is mineral precipitation during a regional hydrothermal event. Burial diagenesis does not explain the fluid inclusion homogenization temperatures of 90°C and greater unless geothermal gradients are higher than 35°C/km or burial depth is increased to 3 km or more. However, thermal maturity of organic matter in the Michigan Basin suggests Ordovician strata were never buried more than 2 km. Four models for regional hydrothermal fluid migration are: (1) gravity-driven flow; (2) 'squeegee-type' fluid flow; (3) convection cell fluid flow; and (4) structurally-controlled fluid flow. The gravity-driven model relies on continental heat flow and an influx of meteoric water from basin catchment areas. For the 'squeegee, convection cell and structurally controlled models, hot fluids could have entered the region from several conduits concurrently during episodic reactivation of basement faults and fracture systems in response to intracratonic stresses created by the continuous interaction of tectonic plates. Determining which of the models best explains regional hydrothermal fluid flow in the Michigan Basin is difficult for several reasons; (1) surface temperatures and maximum burial temperatures at the time of mineral precipitation in the Michigan Basin during the Ordovician are unknown; (2) the timing of mineral precipitation in relation to tectonic pulses is undetermined; (3) there is as yet no known deep-seated heat sources in the Michigan Basin for convection to occur; and (4) it is unknown whether advection is a major process in the Michigan Basin. A collaborative multi-disciplinary research project covering geology, geophysics and hydrogeology would provide much more integrated data than is currently available from stable isotopes, fluid inclusions and organic matter.
Download or read book Advances in Ordovician Geology written by Christopher R. Barnes and published by . This book was released on 1991 with total page 356 pages. Available in PDF, EPUB and Kindle. Book excerpt: Selected papers from the August 1988 symposium on the Ordovician System. Authors from the U.K., Canada, Australia, and the U.S. contributed papers on a project to redefine regional chronostratigraphic subdivisions. Papers also cover Ordovician paleontology and biostratigraphy, emphasizing conodonts, graptolites and trilobites. The interrelationships of stratigraphy, eustasy, tectonics, and volcanisms are explored, with particular attention to the Appalachian Orogen. The final section of the volume documents some of the new data and interpretations of Ordovician paleo-oceanography, paleoclimatology, and paleogeography.
Download or read book Field Trip Guidebook written by New York State Geological Association and published by . This book was released on 2005 with total page 138 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Stratigraphy of Upper Ordovician and Silurian Rocks in South central Idaho written by James J. Jorsch and published by . This book was released on 1982 with total page 172 pages. Available in PDF, EPUB and Kindle. Book excerpt:
