Two gigantic landslides in carbonate sequences were studied through a combination of remotely sensed datasets and detailed field investigation. Field investigations supplemented the remote analysis at both sites. The work presents the first detailed documentation of the Seymareh (Saidmarreh) landslide, Zagros Mountains, Iran, which is shown to be the largest known rock avalanche in the world and the largest known landslide of any type on the Earth’s land surface. Volume of the Seymareh rock avalanche (38 Gm³) was previously underestimated by nearly 50 percent. The failure mode was complex planar sliding involving fold-related bedding-parallel shears and local break-through of bedding. The overall dip of the sliding surface was 11°. Lateral release and toe release were provided by tectonically-weakened joints and by break-out likely assisted by fluvial undercutting, respectively. Broad scar morphology and outcrop-scale features indicate the presence of nine discrete sliding surfaces distributed through the failed sequence and define nine stacked plates involved in the detachment. The Valley of the Rocks rock avalanche (1.3 Gm³), Rocky Mountains, Canada is described in detail for the first time and shown to be the largest known rock avalanche in North America as well as the largest known landslide of any type in Canada. The failure mode was simple planar sliding along a bedding-parallel, slightly concave-up surface possibly coinciding with a thrust fault (average dip 25°). Lateral release and toe release were provided by bedding-normal joints and by glacial undercutting, respectively. There is a surprisingly high degree of similarity between the two rock avalanches, despite differences in tectonic and climatic setting.. Similarities and differences between the two gigantic landslides suggest several factors important in volume determination of gigantic landslides in carbonate sequences: 1) extensive contiguous source slope; 2) high degree of structural continuity, especially across slope parallel to strike; 3) a comparatively low failure surface dip; 4) discontinuity-parallel slopes, and subsequent toe undercutting; and 5) hard-over-soft geomechanical contrasts. Comparison with magnitude-mobility relationships for landslides over five orders of magnitude shows that the Seymareh rock avalanche suggests an upper limit for landslide mobility (fahrböschung = ~4°) on the Earth’s continental surface.

M. Tech. Chemical and Metallurgical Engineering / Focuses on developing a reproducible, regenerable, effective and affordable adsorbent for the removal of fluoride, phosphorus and arsenic from water. The adsorption media should perform at room or low temperatures. To perform basic mathematical modelling to aid in adsorber design. The specific objectives are as follows: to apply a simple thermo-chemical process to convert limestone into a robust adsorption media ; to pelletize thermo-chemically converted limestone using organic binders ; to determine the effect of binders on arsenic, fluoride and phosphate removal from water and to apply basic models to interpret breakthrough results.

Cement clinker production is a highly resource and energy intensive process and contributes substantially to annual global anthropogenic greenhouse gas emissions. One potential pathway to reduce the environmental footprint of cement-based materials is through the reduction of clinker content in concrete by partial replacement of cement with fillers. In this investigation, the partial replacement of cement with chemically inert nano and microsized fillers of titanium dioxide (TiO₂) and limestone was examined. The effects of nano and micro fillers on early-age properties, long-term properties, photocatalytic properties (for TiO₂-cement mixtures) and life cycle costs were measured and compared. Investigation of early-age properties shows that nanoparticles increase rate and degree of early cement hydration and chemical shrinkage due to heterogeneous nucleation effect. In contrast, coarser microparticles (>3µm in this research) maintain or marginally decrease the rate and degree of early cement hydration and decrease chemical shrinkage due to a dilution effect. In addition, temperature sensitivity of hydration reactions increases in the presence of nanoparticles. Investigation of long-term properties shows that pore size refinement is possible with the partial replacement of cement with nanoparticle fillers. But the long-term tests of filler-cement mixes also demonstrate that, compared to ordinary portland cement mix, the strength decreases and permeability increases. Analysis of photocatalytic properties of TiO₂-cement mixtures showed a lack of an appropriate testing procedure for nitrogen oxide (NOₓ) gas conversion by cement-based materials. Thus, a new standardized procedure and photocatalytic efficiency factor for characterizing photocatalytic NOₓ binding by cementitious materials is proposed. Life cycle analysis demonstrates that although inclusion of TiO₂ increases initial environmental impact of cementitious materials, the innovative photocatalytic properties of TiO₂ could improve sustainability. Life cycle analysis also shows that partial replacement of cement with limestone decreases environmental impact of cementitious mixtures due to lower processing “costs” of limestone compared to cement. Thus, the results from the current research demonstrate that variation of dosage and particle size of inert fillers can be used to tailor properties and structure of cement-based materials and that environmental sustainability can be improved by partial replacement of cement with inert fillers that introduce additional functionalities or fillers with lower embodied-energy and emissions.

The Bridal Veil Falls Limestone (lowest 400 meters of the Permo-Carboniferous Oquirrh Group) is well exposed on the flanks of Cascade Mountain (Wasatch Front and adjacent mountain ranges) near Provo, Utah. Because of its excellent exposure and location in the heart of the Oquirrh depocenter, this area was selected to develop a sequence stratigraphic framework for Morrowan rocks that may be applied throughout the Oquirrh basin (NW Utah and southern Idaho) as well as the adjacent Ely and Bird Springs troughs. Eleven partial to complete sections of the Bridal Veil Falls Limestone were measured along the west and north flanks of Cascade Mountain and the south end of Mt. Timpanogos. There the limestone is comprised principally of mud-rich carbonate lithofacies punctuated by thin, and sometimes discontinuous quartzose sandstone beds. The predominance of muddy to grain-rich heterozoan limestone microfacies suggests deposition on a west-dipping low energy carbonate ramp that prograded westward throughout Morrowan time. Sandstones reflect transport of siliciclastics from the incipient Weber shelf (located to the NE) during episodes of sea-level lowstand. The Bridal Veil Falls Limestone is subdivided into 21, third and fourth order depositional sequences ranging in thickness from 3 to 60 meters, and 62 parasequences. Parasequences are commonly asymmetrical, reflecting rapid flooding followed by protracted shoaling and/or sea level drop. Selected cycles are recognized in the Lake Mountains, Thorpe Hills, and the southern Oquirrh Mountains to the west of Cascade Mountain indicating that Parasequences delineated at Cascade Mountain are regionally extensive over an area of at least 300 square kilometers.

The oèolitic limestone that makes up the bedrock of Miami-Dade and parts of Broward County, Florida, is a relatively well studied formation, with poorly studied fossil content. No published systematic record of Pleistocene fossils in the Miami Limestone is available. Besides the basic knowledge of taxonomy and biodiversity of the mollusks, comparison with extant assemblages can yield important information about the biodiversity changes in southern Florida during the past ~130,000 years. Preliminary surveys of several localities, both previously described and new, within the Dade County yielded a record of diverse mollusks from over 28 families, 34 genera and 40 species. The preliminary findings of molluscan fossils have led to a new, unstudied and unpublished fossil locality with the second discovery of a possible Strombus costatus in the Miami Limestone. Miami Limestone fossils are being compared to recent South Florida mollusks indicating patterns of local diversification and extinction related to the minor changes in sea level and disappearance of certain habitats such as the rocky shore substrates that Cittarium pica once thrived on. / by Heather M. D'Antonio. / Thesis (M.S.)--Florida Atlantic University, 2012. / Includes bibliography. / Electronic reproduction. Boca Raton, Fla., 2012. Mode of access: World Wide Web.

In geschichteten Reservoiren mit geringer Matrix-Permeabilität kontrollieren überwiegend Bruchsysteme den Fluidtransport. In Kalk-Mergel-Wechselfolgen sind allerdings die vertikale Kluftausbreitung sowie die Vernetzung der Kluftsysteme zwischen den unterschiedlichen Schichten sehr variabel, was schließlich die Permeabilität in diesen bruchkontrollierten Reservoiren erheblich beeinflusst. Innerhalb einer Schichtfolge führen diverse sedimentologische Merkmale (z.B. sedimentäre Schichtung und diagenetische Bankung) zu kontrastreichen Gesteinseigenschaften und wirken somit als Spannungsbarrieren. Spannungsbarrieren, wie beispielsweise lithologische Kontakte oder mächtige Mergellagen, können die Kluftausbreitung in geschichteten Gesteinen ebenfalls verhindern und erschweren zusätzlich die Vorhersage potentieller Fluidwege. Aufgrund dessen ist es entscheidend Schichten, die sich mechanisch einheitlich verhalten („mechanische Einheit“) zu finden. Das Ziel dieser Doktorarbeit ist, den Einfluss von sedimentologischen und diagenetischen Merkmalen und petrophysikalischen Eigenschaften vertikaler Kluftausbreitung in Kalk-Mergel-Wechselfolgen der Jurassischen Blue Lias Formation (Bristol Channel Becken, Großbritannien) abzuschätzen, um verschiedenartige Spannungsbarrieren und mechanische Einheiten zu definieren. Zu diesem Zweck wurden sechs Profile untersucht, welche sich durch unterschiedliche morphologische Variationen auszeichnen (d.h. von kalkdominiert zu mergeldominiert). Die Untersuchungen umfassen Kombinationen aus sedimentologischer (z.B. Geländeuntersuchungen, Dünnschliffpetrografie, Rasterelektronenmikroskopie, CaCO3- and Corg-Messungen), quantitativ strukturgeologischer (z.B. Charakterisierung von Kluftsystemen) sowie petrophysikalischer Daten (z.B. Spaltzug- und Druckfestigkeits-, Rückprallhärte- und Porositäts-Messungen). Im Rahmen der quantitativen strukturgeologischen Untersuchungen wurden unter Verwendung einer modifizierten Scanline Methode (Durchführung einer flächengestützten Kluftanalyse) über 4000 schichtübergreifende Klüfte betrachtet. Generell wird angenommen, dass der Kluftabstand mit zunehmender Bankmächtigkeit zunimmt und die Kluftdichte dementsprechend abnimmt. Diese Studie zeigt jedoch, dass dieser Zusammenhang nur eingeschränkt auf Kalkbänke dieser Abfolgen anwendbar ist und nur auf Schichten mit lateral planaren Oberflächen (wohlgebankte Kalkbänke) übertragen werden kann. Bei Bänken gleicher Mächtigkeit mit allerdings irregulären Oberflächen (semiknollige Kalkbänke) variieren die Kluftabstände innerhalb dieser Bänke beträchtlich. Das bedeutet, die Kluftabstände sind in semiknolligen Kalkbänken eher unregelmäßig wohingegen die Abstände in wohlgebankten Bänken eher regelmäßig sind. Des Weiteren sind in wohlgebankten Kalken ein höherer prozentualer Anteil von schichtgebundenen Klüften (57 %) ausgebildet. Dagegen sind in semiknolligen Kalken ein höherer Anteil nicht-schichtgebundener Klüfte ausgebildet (67 %). Entscheidend für die Kluftausbreitung in geschichteten Gesteinen ist nicht nur die Kluftverteilung der einzelnen Bänke, sondern auch verschiedenartige Spannungsbarrieren, wie beispielsweise lithologische Kontakte, Mächtigkeiten und Heterogenitäten von Mergeln hemmen die Kluftausbreitung. Anhand der vertikalen Kluftstoppung an lithologischen Kontakten und vertikale Kluftausbreitung durch Schichten wurden Spannungsbarrieren identifiziert (schichtgebundene vs. nicht-schichtgebundene Klüfte). Da nicht alle lithologische Kontakte die Ausbreitung von Klüften in geschichteten Gesteinen verhindern, wurde in dieser Studie der Terminus für 50 % Kluftstoppung an diesen Kontakten verwendet („mechanische Grenzflächen“). Zusätzlich wurden bestimmte Mergellagen, die >0.20 m mächtig sind, durch mechanische Grenzflächen begrenzt sind und weniger als 50 % nicht-schichtgebundene Klüfte beinhalten, als „mechanische Puffer“ definiert. Die Charakterisierung des Kluftsystems wird neben der vorherrschenden stark heterogenen Kluftverteilung in der Blue Lias Formation, auch durch eine signifikante Variation des Diagenese-Einflusses von Abschnitt zu Abschnitt erschwert. Beispielsweise wurden in Wales drei Teilprofile genauestens untersucht, welche trotz ihrer räumlich nahen Lage und relativ zeitgleichen Entstehung unterschiedliche sedimentologische und diagenetische Merkmale in Meter- bis Mikrometer-Skalen aufweisen (von früh lithifiziert bis physikalisch kompaktierte Abfolgen). Darüber hinaus sind diese durch unterschiedliche Muster der Kluftstoppung an Kontakten und Kluftausbreitung innerhalb der Bänke charakterisiert. Lithologische Kontakte in diagenetisch beeinflussten Abfolgen sind tendenziell eher graduell und somit keine mechanischen Grenzflächen. Wenn zusätzlich der Unterschied zwischen den CaCO3-Konzentrationen zwischen Kalken und Mergeln niedrig ist, kann die Abfolge als eine mechanische Einheit definiert werden, welches die Kluftausbreitung begünstigen würde. Die Vorhersage der Konnektivität von Kluftnetzwerken ist in lithologisch heterogenen Kalk-Mergel-Wechselfolgen, wie die in der Blue Lias Formation, aufgrund unterschiedlicher Kluftverteilung innerhalb einzelner Bänke, unterschiedliche diagenetische Einfluss und verschiedenartiger Spannungsbarrieren schwierig. Das ist insbesondere für die Charakterisierung der Kluftnetzwerke und ihre Nutzung in Aufschluss-Analogstudien problematisch, welche für die Einschätzung des Fluidtransports in solchen Systemen verwendet wird. Die Ergebnisse dieser Studie sind zur Optimierung der Quantifizierung von Kluftverteilung und -ausbreitung in heterogenen Gesteinsabfolgen entscheidend und präzisieren die Definition mechanischer Einheiten. Diese Definition ist eine wichtige Voraussetzung für die Vorhersage von Kluftpermeabilitäten und folglich entscheidend für Fluidtransportmodelle.

No description available.

The Miocene Nullarbor Limestone is the most recent formation in the Cenozoic Eucla Group and was deposited in the Eucla Basin, southern Australia, at ~38°S paleolatitude during the early to middle Miocene. The rocks form the modern surface of the vast, karsted Nullarbor Plain. Older Eucla Group marine carbonates (Eocene-earliest Miocene) are cool-water in nature and dominated by bryozoans and echinoderms. The Nullarbor Limestone is subtropical in composition and rich in coralline algae (rhodoliths and articulated types), large and small benthic foraminifera and molluscs. Diverse zooxanthellate corals are also present but not numerous. Deposition is interpreted to have taken place in three main paleoenvironments: rhodolith gravels, seagrass banks, and open seafloors. The Southern Ocean extended inboard ~450 km from the shelf edge during Nullarbor Limestone deposition. Interpreted paleodepths ranged from the top to the base of the photic zone, implying a small slope over a wide shelf. The Miocene Eucla platform is therefore interpreted to have been epeiric in nature. Paleoenvironment distribution is explained using epeiric platform sedimentation patterns and comparisons with modern environments. Open seafloor environments, the deepest settings, are thought to have been below fair-weather wave base. Rhodolith gravels accumulated at intermediate depths, where waves frequently swept the seafloor. Seagrass banks developed in the shallowest waters farthest inboard, where wave energy had been largely dissipated. Diverse corals, large benthic foraminifera and micrite envelopes inboard and in the western part of the basin support the notion of paleotemperatures generally above 20°C, the upper limit of subtropical carbonate accumulation. Although deposition occurred during the Miocene Climatic Optimum, a simple overall temperature increase cannot completely account for the subtropical nature of these sediments at mid-latitudes. Tropical components decrease from west to east, implying a temperature gradient, probably due to the warm proto-Leeuwin Current. Thus, these subtropical carbonates were deposited at mid-latitudes and their presence did not simply reflect a change in global climate. / Thesis (Master, Geological Sciences & Geological Engineering) -- Queen's University, 2010-12-23 16:05:47.981

Fanny Creek drains from Island Block opencast coal mine, near Reefton on the West Coast of the South Island of New Zealand, and is impacted by acid mine drainage (AMD). The objectives of this study were to characterise drainage chemistry in Fanny Creek catchment, and to determine optimal passive treatment strategies for Fanny Creek AMD for future pilot or full-scale application. This was undertaken by monthly monitoring in Fanny Creek catchment between February 2008 and January 2009 to collect drainage chemistry and flow data. Laboratory trials of suitable passive AMD treatment systems were conducted and their treatment performance assessed to select and design optimal passive treatment strategies for Fanny Creek AMD. Oxidation of pyrite in Brunner Coal Measure sediments at Island Block mine generates AMD. Fanny Creek originates from a number of AMD seeps on the eastern waste rock slope of Island Block mine. Seeps have low pH (<3.23) and a single detailed metal analysis indicates drainage is enriched with aluminium and iron, and contains elevated concentrations of manganese, copper, nickel, zinc and cadmium relative to applicable water quality criteria such as ANZECC guidelines. Acidity and metal loadings of drainage in the catchment indicates AMD from the northern waste rock slope contributes most of the acidity (~70%) and metal (60%) in Fanny Creek, and acts to re-dissolve additional metals upon mixing with drainage from other slopes. The most suitable location for a passive AMD treatment system in Fanny Creek catchment is on the Waitahu Valley floor, near monitoring site R12, because this allows for sediment removal prior to a treatment system. Fanny Creek AMD at site R12 was characterized in detail because this data assists with selection and design of passive AMD treatment systems. Fanny Creek at site R12 contains on average 6.0 mg/L aluminium, 1.3 mg/L iron, 3.1 mg/L manganese, 0.49 mg/L zinc, 0.14 mg/L nickel, 0.0071 mg/L copper and 0.00048 mg/L cadmium. Average pH at site R12 was 3.95, calculated acidity averaged 42.7 mg CaCO₃/L, and flow rate ranged from 1.5 L/s to about 30 L/s. Acidity and metal generation from Island Block mine increases linearly with flow in the catchment, and therefore Fanny Creek drainage chemistry is not significantly affected by rainfall dilution. Natural attenuation of AMD occurs by addition of un-impacted alkaline drainage from Greenland Group basement rocks, wetland ecosystem processes, and geochemical reactions along Fanny Creek that decrease acidity and metal concentrations before AMD discharges into the Waitahu River. During low flow conditions (summer months), surface flow of AMD into the Waitahu River does not occur because of subsurface flow loss. Three suitable passive AMD treatment options for Fanny Creek AMD were selected and trialed at ‘bench top’ scale in a laboratory. These included a sulfate reducing bioreactor (SRBR), a limestone leaching bed (LLB), and an open limestone channel (OLC). The potential to mix Waitahu River water with Fanny Creek to neutralize AMD was also investigated. Fanny Creek AMD was employed for laboratory trials, and influent flow rates into SRBR, LLB and OLC systems were regulated to assess performance at different hydraulic retention times (HRT). Optimal HRTs for future treatment system designs were determined from effective AMD treatment thresholds, and include 51 hours, 5 hours and 15 hours for SRBR, LLB and OLC systems, respectively. To determine optimal treatment options for Fanny Creek AMD the effectiveness of each trial option was compared to applicable water quality criteria, and scale up implications of treatment options was assessed. The SRBR system had most effective AMD treatment, with water quality criteria achieved for metals, greatest alkalinity generation, and highest pH increase. However, a full scale SRBR system has significant size requirements, and long term treatment performance may be limited. The LLB system decreased metals to below, or just slightly above criteria for all metals, and has significantly smaller size requirements compared to a SRBR system. The OLC system was least effective, with effluent above water quality criteria for all metals except iron, and with lowest alkalinity generation. The Waitahu River is capable of neutralizing AMD because it is slightly alkaline. The flow volume of river water required for neutralization is between 65 L/s and 140L/s, which can be gravity fed to mix with Fanny Creek. These results indicate that either a LLB treatment system or the Waitahu River Mixing option are the optimal passive treatment strategies for Fanny Creek AMD. On site pilot scale testing of SRBR and LLB systems, and the Waitahu River Mixing option is recommended because of AMD treatment uncertainty, and to more accurately select and design full scale passive treatment strategies.

The Early Pennsylvanian (Bashkirian/Morrowan) Bridal Veil Limestone of north-central Utah was deposited in the eastern portion of the rapidly subsiding Oquirrh basin. The 420 meter-thick Bridal Veil Limestone displays distinct cyclicity formed by stacked, meter to decameter scale high-frequency sequences and their constituent parasequences. Though no one ideal cycle may be defined for the Bridal Veil Limestone, each high-frequency sequence and parasequence contains a general shallowing upward trend that ranges from anaerobic to dysaerobic mudstone at the base to skeletal wackestone to mud-dominated packstone, capped by heterozoan grain-rich carbonates or siliciclastic tidalites. Cycles bounded by exposure surfaces, indicated by micro-brecciation, rhizoliths, laminated calcite or silica crusts, rip-up clasts, centimeter-scale teepee structures, and/or pronounced erosional relief are termed high-frequency sequences. Those bounded by marine flooding surfaces are defined as parasequences. Thusly defined, the Bridal Veil Limestone is divided into 25 high-frequency sequences designated BVL-1 through BVL-25. Overall, two distinct sets of high-frequency sequences may be observed in the Bridal Veil Limestone. Sequences comprising the lower half of the formation (BVL-1 through BVL-12) are thicker, muddier, and less sand-prone than sequences in the upper half of the formation (BVL-13 through BVL-25), indicating an overall change in oxygenation, depositional texture, and accommodation upward in the section. Tracing of key beds and surfaces between the Thorpe Hills, Lake Mountain, and the Wasatch Range (spanning a distance greater than 50 miles) reveals that deposition was remarkably uniform across the southeastern part of the Oquirrh basin which we herein designate the Bridal Veil sub-basin and distinct from coeval formations in the southern Oquirrh basin, Ely basin, and Wyoming shelf. Mudstone and wackestone textures comprise a large portion of the formation by volume. Grain-rich carbonates are almost exclusively heterozoan in composition, indicating that the sub-basin was subphotic to aphotic through Early Pennsylvanian time.