Stratigraphy of Architectural Elements of a Buried Monogenetic Volcanic System

Large volumes of magma emplaced and deposited within sedimentary basins can have an impact on the architecture and geological evolution of these basins. Over the last decade, continuous improvement in techniques such as seismic volcano-stratigraphy and 3D visualisation of igneous bodies has helped increase knowledge about the architecture of volcanic systems buried in sedimentary basins. Here, we present the complete architecture of the Maahunui Volcanic System (MVS), a middle Miocene monogenetic volcanic field now buried in the offshore Canterbury Basin, South Island of New Zealand. We show the location, geometry, size, and stratigraphic relationships between 25 main intrusive, extrusive and sedimentary architectural elements, in a comprehensive volcano-stratigraphic framework that explains the evolution of the MVS from emplacement to complete burial in the host sedimentary basin. The plumbing system of the MVS comprises saucer-shaped sills, dikes and sill swarms, minor stocks and laccoliths, and pre-eruptive strata deformed by intrusions. The eruptive and associated sedimentary architectural elements define the morphology of volcanoes in the MVS, which comprise deep-water equivalents of crater and cone-type volcanoes. After volcanism ceased, the process of degradation and burial of volcanic edifices formed sedimentary architectural elements such as inter-cone plains, epiclastic plumes, and canyons. Understanding the relationships between these diverse architectural elements allows us to reconstruct the complete architecture of the MVS, including its shallow (<3 km) plumbing system, the morphology of the volcanoes, and their impact in the host sedimentary basin during their burial. Insights from the architecture of the MVS can be used to explore for geoenergy resources such as oil, gas and geothermal energy in buried and active monogenetic volcanic systems elsewhere.

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Stratigraphy of Architectural Elements of a Buried Monogenetic Volcanic System

Open Geosciences ◽

10.1515/geo-2019-0048 ◽

2019 ◽

Vol 11 (1) ◽

pp. 581-616 ◽

Cited By ~ 6

Author(s):

Alan Bischoff ◽

Andrew Nicol ◽

Jim Cole ◽

Darren Gravley

Keyword(s):

Geothermal Energy ◽

Sedimentary Basin ◽

Sedimentary Basins ◽

Volcanic Field ◽

Plumbing System ◽

Volcanic System ◽

Architectural Elements ◽

Stratigraphic Framework ◽

Cone Type ◽

Geological Evolution

Abstract Large volumes of magma emplaced and deposited within sedimentary basins can have an impact on the architecture and geological evolution of these basins. Over the last decade, continuous improvement in techniques such as seismic volcano-stratigraphy and 3D visualisation of igneous bodies has helped increase knowledge about the architecture of volcanic systems buried in sedimentary basins. Here, we present the complete architecture of the Maahunui Volcanic System (MVS), a middle Miocene monogenetic volcanic field now buried in the offshore Canterbury Basin, South Island of New Zealand. We show the location, geometry, size, and stratigraphic relationships between 25 main intrusive, extrusive and sedimentary architectural elements, in a comprehensive volcano-stratigraphic framework that explains the evolution of the MVS from emplacement to complete burial in the host sedimentary basin. Understanding the relationships between these diverse architectural elements allows us to reconstruct the complete architecture of the MVS, including its shallow (<3 km) plumbing system, the morphology of the volcanoes, and their impact in the host sedimentary basin during their burial. The plumbing system of the MVS comprises saucer-shaped sills, dikes and sill swarms, minor stocks and laccoliths, and pre-eruptive strata deformed by intrusions. The eruptive and associated sedimentary architectural elements define the morphology of volcanoes in the MVS, which comprise deep-water equivalents of crater and cone-type volcanoes. After volcanism ceased, the process of degradation and burial of volcanic edifices formed sedimentary architectural elements such as inter-cone plains, epiclastic plumes, and canyons. Insights from the architecture of the MVS can be used to explore for natural resources such as hydrocarbons, geothermal energy and minerals in buried and active volcanic systems elsewhere.

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Geodynamics and geothermics of Pre-Caspian Depression and eastern segment of Caucasus region

Геология и геофизика Юга России ◽

10.46698/vnc.2020.92.72.004 ◽

2020 ◽

pp. 52-69

Author(s):

В.Б. Свалова

Keyword(s):

Sedimentary Basin ◽

Sedimentary Cover ◽

Sedimentary Basins ◽

Caucasus Region ◽

Himalayan Belt ◽

Eastern Segment ◽

Caspian Depression ◽

Formation And Evolution ◽

Gas Potential ◽

Oil Gas

Актуальность работы определяется важностью оценки и прогноза нефтегазового потенциала глубоких осадочных бассейнов, в частности, глубоких горизонтов структур, не всегда доступных глубокому бурению в поисковых и разведочных целях. Цель и методы исследования. Наряду с прикладными вопроса- ми целью исследования являются фундаментальные вопросы теоретической геодинамики формирования и эволюции осадочных бассейнов в связи с подъемом мантийных диапиров на основе методов механи- ко-математического моделирования. Прикаспийская впадина и восточный сегмент Кавказского региона, включая Каспийское море, могут рассматриваться как регионы окрестности восточной части Альпийского пояса, который в свою очередь является западной частью Альпийско-Гималайского пояса, простирающе- гося от западной оконечности Средиземного моря до Тихоокеанского побережья. Каспийское море пере- секает с севера на юг серию широтных структурных зон юго-восточной окраины древней докембрийской Восточно-Европейской платформы, молодой эпигерцинской Скифско-Туранской платформы и современ- ного Альпийско-Гималайского орогенного пояса. Прикаспийская и Южно-Каспийская впадины являются глубокими осадочными бассейнами с толщиной осадочного чехла более 20 км, обладающими высоким нефтегазовым потенциалом и большим народно-хозяйственным значением. Формирование и эволюция осадочного бассейна служат ключом для определения зон нефтегенерации осадочного чехла, что делает задачу изучения геодинамики осадочных бассейнов крайне важной и необходимой. Геодинамика релье- фа поверхности определяется глубинными мантийными движениями. Механико-математическая модель динамики литосферы дает возможность количественно связать параметры формирующегося осадочного бассейна с подъемом мантийного диапира. Анализ геофизических полей геологических структур позволя- ет оценить подъем астеносферы, а разработанная самосопряженная термогравиметрическая модель ли- тосферы делает эти оценки надежными и достоверными. Геодинамика и история развития геологических структур определяют магматизм, вулканизм, сейсмичность, геотермические характеристики, геотермаль- ную активность, нефтегазоносность, опасные природные процессы региона, что в свою очередь является обоснованием создания системы комплексного экологического мониторинга на фундаментальной научной базе, прогноза и предупреждения природных бедствий и катастроф, а также поиска полезных ископаемых, включая углеводороды. Результатом работы является количественная оценка подъема астеносферы под осадочным бассейном на примере Прикаспийской впадины The relevance of the work is determined by the importance of assessing and predicting the oil and gas potential of deep sedimentary basins, in particular, deep horizons of structures that are not always accessible to deep drilling for prospecting and exploration purposes. The aim and research methods. Along with applied questions, the aim of the study is the fundamental questions of the theoretical geodynamics of the formation and evolution of sedimentary basins in connection with the rise of mantle diapirs based on the methods of mechanical and mathematical modeling. Pre-Caspian Depression and eastern segment of Caucasus region, including Caspian Sea, can be considered as regions of area of eastern part of Alpine belt, which is western part of Alpine-Himalayan belt disposed from Mediterranean sea to Pacific Ocean. Caspian sea crosses from North to South the series of structural zones of East European platform, Scythian-Turan platform and Alpine-Himalayan belt. Pre-Caspian Depression and South Caspian Depression are deep sedimentary basins with thickness of sedimentary cover more than 20 km which have high oil-gas potential and big industrial importance. Formation and evolution of sedimentary basin is the clue for oil-gas generation zones of sedimentary cover, that makes the problem of sedimentary basins geodynamics of great importance one. Geodynamics of relief is defined by deep mantle movements. Mechanical-mathematical model of the lithosphere dynamics gives possibility to link the basin parameters with mantle diaper upwelling. Analysis of geophysical fields gives opportunity to evaluate the asthenosphere upwelling, and elaborated self-conjugated thermo-gravimetric model makes this evaluation reliable and trustworthy one. Geodynamics and evolution history of geological structures determine magmatism, volcanism, seismicity, geothermics, geothermal manifestations, oil-gas potential, natural hazards of region, that is basement for monitoring system creation and construction on fundamental scientific base, forecast and prognosis of natural catastrophes and oil-gas potential researches. The result of this work is a quantitative assessment of the rise of the asthenosphere under the sedimentary basin using the example of the Pre-Caspian Depression

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Stratigraphy of architectural elements in a buried volcanic system and implications for hydrocarbon exploration

Interpretation ◽

10.1190/int-2016-0201.1 ◽

2017 ◽

Vol 5 (3) ◽

pp. SK141-SK159 ◽

Cited By ~ 23

Author(s):

Alan Patrick Bischoff ◽

Andrew Nicol ◽

Mac Beggs

Keyword(s):

Temporal Distribution ◽

Large Data ◽

Sedimentary Basins ◽

Building Blocks ◽

Hydrocarbon Exploration ◽

Coarse Grained ◽

Data Set ◽

Volcanic System ◽

Architectural Elements ◽

Spatio Temporal

The interaction between magmatism and sedimentation creates a range of petroleum plays at different stratigraphic levels due to the emplacement and burial of volcanoes. This study characterizes the spatio-temporal distribution of the fundamental building blocks (i.e., architectural elements) of a buried volcano and enclosing sedimentary strata to provide insights for hydrocarbon exploration in volcanic systems. We use a large data set of wells and seismic reflection surveys from the offshore Taranaki Basin, New Zealand, compared with outcropping volcanic systems worldwide to demonstrate the local impacts of magmatism on the evolution of the host sedimentary basin and petroleum system. We discover the architecture of Kora volcano, a Miocene andesitic polygenetic stratovolcano that is currently buried by more than 1000 m of sedimentary strata and hosts a subcommercial discovery within volcanogenic deposits. The 22 individual architectural elements have been characterized within three main stratigraphic sequences of the Kora volcanic system. These sequences are referred to as premagmatic (predate magmatism), synmagmatic (defined by the occurrence of intrusive, eruptive, and sedimentary architectural elements), and postmagmatic (degradation and burial of the volcanic structures after magmatism ceased). Potential petroleum plays were identified based on the distribution of the architectural elements and on the geologic circumstances resulting from the interaction between magmatism and sedimentation. At the endogenous level, emplacement of magma forms structural traps, such as drag folds and strata jacked up above intrusions. At the exogenous level, syneruptive, intereruptive, and postmagmatic processes mainly form stratigraphic and paleogeomorphic traps, such as interbedded volcano-sedimentary deposits, and upturned pinchout of volcanogenic and nonvolcanogenic coarse-grained deposits onto the volcanic edifice. Potential reservoirs are located at systematic vertical and lateral distances from eruptive centers. We have determined that identifying the architectural elements of buried volcanoes is necessary for building predictive models and for derisking hydrocarbon exploration in sedimentary basins affected by magmatism.

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Evidence of active magmatic rifting at the Ma’Alalta volcanic field (Afar, Ethiopia)

Bulletin of Volcanology ◽

10.1007/s00445-021-01461-4 ◽

2021 ◽

Vol 83 (6) ◽

Author(s):

Gianmaria Tortelli ◽

Anna Gioncada ◽

Carolina Pagli ◽

Mauro Rosi ◽

Laura De Dosso ◽

...

Keyword(s):

Seismic Data ◽

Volcanic Field ◽

Lava Flows ◽

Magmatic Activity ◽

Magma Storage ◽

Plumbing System ◽

Mafic Lava ◽

Cinder Cones ◽

Mafic Rocks ◽

Seismic Networks

AbstractDuring continental rifting, strain and magmatism are believed to localize to narrow magmatic segments, while the rift margin is progressively abandoned. We integrate volcanological, geochemical, petrological and seismic data from the Ma’Alalta volcanic field (MVF) near the western margin of Afar, to show that the MVF is an active magmatic segment. Magmatism in MVF initiated with lava flows and large-volume, caldera-forming ignimbrites from a central edifice. However, the most recent magmatic activity shifted towards mafic lava fields, cinder cones and obsidian-rich silicic domes erupted from vents aligned NNW-SSE, defining a ~ 35-km-long magmatic segment. Along the same area, a NNW-SSE alignment of earthquakes was recorded by two local seismic networks (2005–2009 and 2011–2013). The geochemistry of the mafic rocks is similar to those of nearby axial volcanoes. Inferred magma storage depth from mineral geobarometry shows that a shallow, silicic chamber existed at ~ 5-km depth below the stratovolcano, while a stacked plumbing system with at least three magma storage levels between 9 and 24 km depth fed the recent basalts. We interpret the wide set of observations from the MVF as evidence that the area is an active magmatic segment, showing that localised axial extension can be heavily offset towards the rift margin.

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Estimating the Geothermal Electricity Generation Potential of Sedimentary Basins Using genGEO (The Generalizable GEOthermal Techno-Economic Simulator)

10.26434/chemrxiv.13514440 ◽

2021 ◽

Author(s):

Benjamin Adams ◽

Jonathan Ogland-Hand ◽

Jeffrey M. Bielicki ◽

Philipp Schädle ◽

Martin Saar

Keyword(s):

Electricity Generation ◽

Power Plants ◽

Sedimentary Basin ◽

Sedimentary Basins ◽

Heat Extraction ◽

Subsurface Water ◽

Geothermal Heat ◽

Geothermal Resources ◽

Geothermal Power ◽

Economic Tools

AbstractSedimentary basins are ubiquitous, naturally porous and permeable, and the geothermal heat in these basins can be extracted with geologic water or CO2 and used to generate electricity. Despite this, the broad potential that these formations may have for electricity generation is unknown. Here we investigate this potential, which required the creation of the generalizable GEOthermal techno-economic simulator (genGEO). genGEO is built with only publicly available data and uses five standalone, but integrated, models that directly simulate all components of geothermal power plants to estimate electricity generation and cost. As a result of this structure, genGEO, or a portion of it, can be applied or extended to study any geothermal power technology. In contrast, the current techno-economic tools for geothermal power plants rely on characterizations of unpublished ASPEN results and are thus not generalizable enough to be applied to sedimentary basin geothermal power plants which use subsurface CO2. In this study, we present genGEO as open-source software, validate it with industry data, and compare its estimates to other geothermal techno-economic tools. We then apply genGEO to sedimentary basin geothermal resources and find that using CO2 as a subsurface heat extraction fluid compared to water decreases the cost of geothermal electricity across most geologic conditions that are representative of sedimentary basins. Using genGEO results and p50 geologic data, we produce supply curves for sedimentary basin geothermal power plants in the U.S., which suggests that there is present-day potential to profitably increase the capacity of geothermal power by ~10% using water as the subsurface heat extraction fluid. More capacity is available at lower cost when CO2 is used as the subsurface fluid, but realizing this capacity requires geologically storing between ~2 and ~7 MtCO2/MWe. But developing sedimentary basin resources in the short-term using subsurface water may not eliminate options for CO₂-based power plants in the long-term because the least-cost order of sedimentary basins is not the same for both CO2 and water. With sufficient geologic CO2 storage, developing sedimentary basins using CO2- and water-based power plants may be able to proceed in parallel.

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Realistic modelling of observed seismic motion in compIex sedimentary basins

Annals of Geophysics ◽

10.4401/ag-4141 ◽

1994 ◽

Vol 37 (6) ◽

Author(s):

D. Fah ◽

G. F. Panza

Keyword(s):

Ground Motion ◽

Mexico City ◽

Sedimentary Basin ◽

Numerical Technique ◽

Sedimentary Basins ◽

Space Distribution ◽

Soil Conditions ◽

Macroseismic Data ◽

Resonance Effects ◽

Local Soil

Three applications of a numerical technique are illustrated to model realistically the seismic ground motion for complex two-dimensional structures. First we consider a sedimentary basin in the Friuli region, and we model strong motion records from an aftershock of the 1976 earthquake. Then we simulate the ground motion caused in Rome by the 1915, Fucino (Italy) earthquake, and we compare our modelling with the damage distribution observed in the town. Finally we deal with the interpretation of ground motion recorded in Mexico City, as a consequence of earthquakes in the Mexican subduction zone. The synthetic signals explain the major characteristics (relative amplitudes, spectral amplification, frequency content) of the considered seismograms, and the space distribution of the available macroseismic data. For the sedimentary basin in the Friuli area, parametric studies demonstrate the relevant sensitivity of the computed ground motion to small changes in the subsurface topography of the sedimentary basin, and in the velocity and quality factor of the sediments. The relative Arias Intensity, determined from our numerical simulation in Rome, is in very good agreoment with the distribution of damage observed during the Fucino earthquake. For epicentral distances in the range 50 km-100 km, the source location and not only the local soil conditions control the local effects. For Mexico City, the observed ground motion can be explained as resonance effects and as excitation of local surface waves, and the theoretical and the observed maximum spectral amplifications are very similar. In general, our numerical simulations estimate the maximum and average spectral amplification for specific sites, i.e. they are a very powerful tool for accurate micro-zonation

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Contrasting fold styles in a volcano-sedimentary succession

Canadian Journal of Earth Sciences ◽

10.1139/e96-090 ◽

1996 ◽

Vol 33 (8) ◽

pp. 1193-1200

Author(s):

Pierre A. Cousineau ◽

Robert Marquis

Keyword(s):

Sedimentary Basin ◽

Volcanic Rocks ◽

Sedimentary Rocks ◽

Structural Models ◽

Sedimentary Basins ◽

Basaltic Rocks ◽

Field Evidence ◽

Sedimentary Succession

Structural analyses of folded volcano-sedimentary basins rely heavily on the identification and use of way-up structures. These structures are more numerous and widespread in sedimentary rocks than in volcanic rocks. Structural models for such basins can therefore be biased by this fact. The Caldwell Group of the Quebec Appalachians is a folded volcano-sedimentary basin bounded bay major faults. It contains locally abundant basalt-rich bands. Near Lac-Etchemin, way-up in basalt flows is determined by pillow shelves that reflect paleohorizontal planes. The strike and dip of these shelf structures were measured and plotted on stereographic projections. Field evidence and the interpretation of stereographic projections indicate that the basalt-rich bands form open folds that plunge gently to the southwest. However, sandstone-rich bands form tight folds with undulating hinge lines (sheath-like). During initial folding, the basalt formed competent bands with limited aerial extent that were fractured by synthetic and antithetic faults rather than folded. The basalt slivers maintained a near-horizontal attitude while adjacent sedimentary rocks were folded and faulted. Further shortening tightened folds in the sediment-rich bands while producing open folds in slivers of basaltic rocks.

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Eruptive frequency of the Bora-Baricha-Tullu Moye (BBTM) volcanic system in the Central Main Ethiopian Rift

10.5194/egusphere-egu21-13966 ◽

2021 ◽

Author(s):

Amdemichael Zafu Tadesse ◽

Karen Fontijn ◽

Abate Assen Melaku ◽

Ermias Filfilu Gebru ◽

Victoria Smith ◽

...

Keyword(s):

Late Quaternary ◽

Volcanic Eruptions ◽

Volcanic Field ◽

Tectonic Activity ◽

Explosive Eruptions ◽

Ethiopian Rift ◽

Rift System ◽

Diagnostic Features ◽

Volcanic System ◽

Main Ethiopian Rift

The Main Ethiopian Rift (MER) is the northern portion of the East African Rift System and separates the Eastern and Western plateaus of Ethiopia. The recent volcanic and tectonic activity is largely focused within the rift basin along a 20 km wide zone on the rift floor. Large silicic volcanic complexes are aligned along this central rift axis but their eruptive histories are not well constrained.The Bora-Baricha-Tullu Moye (BBTM) volcanic field is situated in the central Main Ethiopian Rift and has a different appearance than the other MER volcanic systems. The BBTM constitutes several late Quaternary edifices, the major ones are: Tullu Moye, Bora and Baricha. In addition, there are multiple smaller eruptive vents (e.g. Oda and Dima), cones, and domes across the ca. 20 X 20 km wide area. Currently, there is very little information on the frequency and magnitude of past volcanic eruptions. We present a new dataset of field observations, componentry, petrography, geochronology (40Ar/39Ar), and glass major and trace element chemistry. The data are assessed as potential fingerprints to assign diagnostic features and correlate units across the area, and establish a tephrostratigraphic framework for the BBTM volcanic field.Two large-volume and presumably caldera-forming eruptions are identified, the younger of which took place at 100 ka. The volcanic products exposed in the BBTM area show that the volcanic field has undergone at least 20 explosive eruptions since then. The post-caldera eruptions have comenditic (Tullu Moye) and pantelleretic (Bora and Baricha) magma compositions. Other smaller edifices such as Oda and Dima also erupted pantelleritic magmas, and only differ slightly in composition than tephra of Bora and Baricha. Tullu Moye had two distinct explosive eruptions that dispersed tephra up to 14 km away and on to the eastern plateau. Bora and Baricha together had at least 8 explosive eruptions. Their deposits can be distinguished by their light grey color and unique lithic components. Oda had 7 eruptions, the most recent of which generated a pyroclastic density current that travelled up to 10 km away from the vent. Dima experienced at least 3 eruptions, generating tephra with a bluish-grey colour.This mapping and compositional analysis of the deposits from the BBTM in the MER indicates that the region has been more active in the last 100 ka than previously thought, which has implications for hazards assessments for the region.

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