Letteratura scientifica selezionata sul tema "Deep Earth dynamics"
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Articoli di riviste sul tema "Deep Earth dynamics"
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Ihnatyshyn, V., D. Malytskyi e Y. Koval'. "Oash deep fault zone: earth`s crust dynamics". Visnyk of Taras Shevchenko National University of Kyiv. Geology, n. 65 (2014): 36–39. http://dx.doi.org/10.17721/1728-2713.65.07.
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Lay, Thorne, Quentin Williams e Edward J. Garnero. "The core–mantle boundary layer and deep Earth dynamics". Nature 392, n. 6675 (aprile 1998): 461–68. http://dx.doi.org/10.1038/33083.
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Heine, Christian, R. Dietmar Müller, Bernhard Steinberger e Lydia DiCaprio. "Integrating deep Earth dynamics in paleogeographic reconstructions of Australia". Tectonophysics 483, n. 1-2 (marzo 2010): 135–50. http://dx.doi.org/10.1016/j.tecto.2009.08.028.
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Saito, Tatsuhiko, e Tatsuya Kubota. "Tsunami Modeling for the Deep Sea and Inside Focal Areas". Annual Review of Earth and Planetary Sciences 48, n. 1 (30 maggio 2020): 121–45. http://dx.doi.org/10.1146/annurev-earth-071719-054845.
Testo completoAbstract (sommario):
This article reviews tsunami modeling and its relation to recent developments of deep-ocean observations. Unlike near-coast observations, deep-ocean observations have enabled the capture of short-wavelength dispersive tsunamis and reflected waves from the coast. By analyzing these waves, researchers can estimate tsunami sources and earthquake slip distributions more reliably with higher spatial resolution. In addition, fractional tsunami speed reduction due to the elasticity of the Earth medium is now clearly detected. Densely and widely distributed tsunami sensors make it possible to observe tsunamis inside the earthquake focal area, and understanding tsunami generation mechanisms is increasingly important. In order to describe the generation field, we should consider seismic waves overlapping tsunami signals in addition to vertical and horizontal displacements at the sea bottom. The importance of elastic dynamics, in addition to fluid dynamics, is increasing in order for researchers to fully understand tsunami phenomena using the new offshore and inside focal area observations. ▪ Deep-ocean observations have advanced tsunami propagation modeling. ▪ New deep-ocean observations in earthquake focal areas are expected to detect in situ tsunami generation caused by megathrust earthquakes. ▪ The importance of elastic dynamics, in addition to fluid dynamics, is increasing to help researchers fully understand mechanics in tsunami generation and propagation. ▪ Tsunami modeling including earthquake rupture and seismic waves contributes to mega-thrust earthquake investigation and disaster mitigation.
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Zhan, Zhongwen. "Mechanisms and Implications of Deep Earthquakes". Annual Review of Earth and Planetary Sciences 48, n. 1 (30 maggio 2020): 147–74. http://dx.doi.org/10.1146/annurev-earth-053018-060314.
Testo completoAbstract (sommario):
Deep earthquakes behave like shallow earthquakes but must have fundamentally different physical processes. Their rupture behaviors, magnitude-frequency statistics, and aftershocks are diverse and imperfectly dependent on various factors, such as slab temperature, depth, and magnitude. The three leading mechanisms for deep earthquakes (i.e., transformational faulting, dehydration embrittlement, and thermal runaway) can each explain portions of the observations but have potentially fundamental difficulties explaining the rest. This situation calls for more serious consideration of hypotheses that involve more than one mechanism. For example, deep earthquakes may initiate by one mechanism, but the ruptures may propagate via another mechanism once triggered. To make further progress, it is critical to evaluate the hypotheses, both single- or dual-mechanism, under conditions as close to those of real slabs as possible to make accurate and specific predictions that are testable using seismic or other geophysical observations. Any new understanding of deep earthquakes promises new constraints on subduction zone structure and dynamics. ▪ Deep earthquakes display the complex structure and dynamics of subduction zones in terms of geometry, stress state, rheology, hydration, and phase changes. ▪ Phase transformation, dehydration, and thermal runaway are the leading mechanisms for deep earthquakes, but all have major gaps or fundamental difficulties. ▪ Deep earthquakes may involve dual-mechanism processes, as hinted at by the diverse rupture and statistic properties and the break of self-similarity. ▪ Further progresses would benefit from specific and testable predictions that consider realistic slab conditions with insights from geodynamics, petrology, and mineral physics.
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Zhatnuev, N. S. "The dynamics of deep magmas". Doklady Earth Sciences 430, n. 2 (febbraio 2010): 176–80. http://dx.doi.org/10.1134/s1028334x10020066.
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Anghelea, Anca, Ewelina Dobrowolska, Gunnar Brandt, Martin Reinhardt, Miguel Mahecha, Tejas Morbagal Harish e Stephan Meissl. "Deep Earth System Data Laboratory (DeepESDL)". International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLVIII-4-2024 (21 ottobre 2024): 13–18. http://dx.doi.org/10.5194/isprs-archives-xlviii-4-2024-13-2024.
Testo completoAbstract (sommario):
Abstract. The Deep Earth System Data Lab (DeepESDL) provides an AI-ready, collaborative environment for researchers aiming to study the Earth's complex dynamics using various datasets and empirical approaches. Recently opened to Early Adopters, it builds on projects like CAB-LAB and ESDL, utilizing well-established Python and Julia technology stacks. DeepESDL offers programmatic access to extensive analysis-ready data cubes and computational resources, enabling researchers to focus on analysis without extensive preparations. Scientists can use persistently available data cubes or generate user-tailored cubes from own data or publicly available datasets. The goal is to streamline data processing through empirical or AI methods within high-dimensional Earth Observation workflows. DeepESDL addresses the complete research cycle, from discovery of earth data to powerful analyses, collaborative scientific research, advanced data visualisation and publication of results, promoting FAIR and Open Science. Apart from serving as a research environment, DeepESDL showcases scientific use cases and supports educational purposes through capacity building, academic programs, and Open Science initiatives. This paper presents an overview of DeepESDL.
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Ferreira, Antónia, João Rolim, Paula Paredes e Maria do Rosário Cameira. "Assessing Spatio-Temporal Dynamics of Deep Percolation Using Crop Evapotranspiration Derived from Earth Observations through Google Earth Engine". Water 14, n. 15 (27 luglio 2022): 2324. http://dx.doi.org/10.3390/w14152324.
Testo completoAbstract (sommario):
Excess irrigation may result in deep percolation and nitrate transport to groundwater. Furthermore, under Mediterranean climate conditions, heavy winter rains often result in high deep percolation, requiring the separate identification of the two sources of deep percolated water. An integrated methodology was developed to estimate the spatio-temporal dynamics of deep percolation, with the actual crop evapotranspiration (ETc act) being derived from satellite images data and processed on the Google Earth Engine (GEE) platform. GEE allowed to extract time series of vegetation indices derived from Sentinel-2 enabling to define the actual crop coefficient (Kc act) curves based on the observed lengths of crop growth stages. The crop growth stage lengths were then used to feed the soil water balance model ISAREG, and the standard Kc values were derived from the literature; thus, allowing the estimation of irrigation water requirements and deep drainage for independent Homogeneous Units of Analysis (HUA) at the Irrigation Scheme. The HUA are defined according to crop, soil type, and irrigation system. The ISAREG model was previously validated for diverse crops at plot level showing a good accuracy using soil water measurements and farmers’ irrigation calendars. Results show that during the crop season, irrigation caused 11 ± 3% of the total deep percolation. When the hotspots associated with the irrigation events corresponded to soils with low suitability for irrigation, the cultivated crop had no influence. However, maize and spring vegetables stood out when the hotspots corresponded to soils with high suitability for irrigation. On average, during the off-season period, deep percolation averaged 54 ± 6% of the annual precipitation. The spatial aggregation into the Irrigation Scheme scale provided a method for earth-observation-based accounting of the irrigation water requirements, with interest for the water user’s association manager, and at the same time for the detection of water losses by deep percolation and of hotspots within the irrigation scheme.
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Syrris, Vasileios, e Sveinung Loekken. "Editorial of Special Issue “Machine and Deep Learning for Earth Observation Data Analysis”". Remote Sensing 13, n. 14 (14 luglio 2021): 2758. http://dx.doi.org/10.3390/rs13142758.
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Nakagawa, Takashi, e Tomoeki Nakakuki. "Dynamics in the Uppermost Lower Mantle: Insights into the Deep Mantle Water Cycle Based on the Numerical Modeling of Subducted Slabs and Global-Scale Mantle Dynamics". Annual Review of Earth and Planetary Sciences 47, n. 1 (30 maggio 2019): 41–66. http://dx.doi.org/10.1146/annurev-earth-053018-060305.
Testo completoAbstract (sommario):
In this review, we address the current status of numerical modeling of the mantle transition zone and uppermost lower mantle, focusing on the hydration mechanism in these areas. The main points are as follows: ( a) Slab stagnation and penetration may play significant roles in transporting the water in the whole mantle, and ( b) a huge amount of water could be absorbed into the deep mantle to preserve the surface seawater over the geologic timescale. However, for further understanding of water circulation in the deep planetary interior, more mineral physics investigations are required to reveal the mechanism of water absorption in the lower mantle and thermochemical interaction across the core–mantle boundary region, which can provide information on material properties to the geodynamics community. Moreover, future investigations should focus on determining the amount of water in the early planetary interior, as suggested by the planetary formation theory of rocky planets. Moreover, the supplying mechanism of water during planetary formation and its evolution caused by plate tectonics are still essential issues because, in geodynamics modeling, a huge amount of water seems to be required to preserve the surface seawater in the present day and to not be dependent on an initial amount of water in Earth's system. ▪ Slab stagnation and penetration of the hydrous lithosphere are essential for understanding the global-scale material circulation. ▪ Thermal feedback caused by water-dependent viscosity is a main driving mechanism of water absorption in the mantle transition zone and uppermost lower mantle. ▪ The hydrous state in the early rocky planets remains to be determined from cosmo- and geochemistry and planetary formation theory. ▪ Volatile cycles in the deep planetary interior may affect the evolution of the surface environment.
Tesi sul tema "Deep Earth dynamics"
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Edwards, Christopher A. (Christopher Andrew). "Dynamics of nonlinear cross-equatorial flow in the deep ocean". Thesis, Massachusetts Institute of Technology, 1996. http://hdl.handle.net/1721.1/10296.
Testo completoAbstract (sommario):
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Earth, Atmospheric, and Planetary Sciences, 1997.Includes bibliographical references (leaves 176-180).
by Christopher A. Edwards.
Ph.D.
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Castle, John C. "Imaging mid-mantle discontinuities : implications for mantle chemistry, dynamics, rheology, and deep earthquakes /". Thesis, Connect to this title online; UW restricted, 1998. http://hdl.handle.net/1773/6809.
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Dell, Rebecca Walsh. "Boundary layer dynamics and deep ocean mixing in Mid-Atlantic Ridge canyons". Thesis, Massachusetts Institute of Technology, 2013. http://hdl.handle.net/1721.1/79282.
Testo completoAbstract (sommario):
Thesis (Ph. D.)--Joint Program in Oceanography (Massachusetts Institute of Technology, Dept. of Earth, Atmospheric, and Planetary Sciences; and the Woods Hole Oceanographic Institution), 2013.Cataloged from PDF version of thesis.
Includes bibliographical references (p. 160-163).
Physical oceanographers have known for several decades the total amount of abyssal mixing and upwelling required to balance the deep-water formation, but are still working to understand the mechanisms and locations-how and where it happens. From observational studies, we know that areas of rough topography are important and the hundreds of Grand-Canyon sized canyons that line mid-ocean ridges have particularly energetic mixing. To better understand the mechanisms by which rough topography translates into energetic currents and mixing, I studied diffusive boundary layers over varying topography using theoretical approaches and idealized numerical simulations using the ROMS model. In this dissertation, I show a variety of previously unidentified characteristics of diffusive boundary layers that are likely relevant for understanding the circulation of the abyssal ocean. These boundary layers share many important properties with observed flows in abyssal canyons, like increased kinetic energy near topographic sills and strong currents running from the abyssal plains up the slopes of the mid-ocean ridges toward their crests. They also have a previously unknown capacity to accelerate into overflows for a variety of oceanographically relevant shapes and sizes of topography. This acceleration happens without external forcing, meaning such overflows may be ubiquitous in the deep ocean. These boundary layers also can force exchange of large volumes of fluid between the relatively unstratified boundary layer and the stratified far-field fluid, altering the stratification far from the boundary. We see these effects in boundary layers in two- and three-dimensions, with and without rotation. In conclusion, these boundary layer processes, though previously neglected, may be a source of a dynamically important amount of abyssal upwelling, profoundly affecting predictions of the basin-scale circulation. This type of mechanism cannot be captured by the kind of mixing parameterizations used in current global climate models, based on a bottom roughness. Therefore, there is much work still to do to better understand how these boundary layers behave in more realistic contexts and how we might incorporate that understanding into climate models.
by Rebecca Walsh Dell.
Ph.D.
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Shephard, Grace. "Linking deep Earth structure and surface topography through geodynamic models". Thesis, The University of Sydney, 2013. http://hdl.handle.net/2123/10184.
Testo completoAbstract (sommario):
It is known that deep Earth and surface processes are intimately linked across broad spatial-temporal scales, however, quantifying this interaction remains elusive. The emergence of coupled plate tectonic and mantle convection, “geodynamic,” models has been facilitated by recent advances in computational resources, numerical solutions of mantle flow and plate model resolution. Five absolute reference frames based on hotspot tracks, palaeomagnetic data and subducted slabs are compared, resulting in differences in plate boundary locations of up to 3000 km and in plate velocities of up to 10 cm/yr. Through a comparison to seismic tomography, differences in predicted mantle structure for features ~20,000 km wide are largely due to velocity variability, and are best reproduced in hotspot frames. Shorter wavelength differences (<4,000 km) are attributed to plate boundary locations and are best reproduced with hybrid hotspot-palaeomagnetic frames. The Jurassic-Cretaceous history of the circum-Arctic is one of the most poorly constrained realms in global plate reconstructions. A revised regional model since 200 Ma, with connected plate boundaries is presented, focusing on the opening and closing the South Anuyi and Oimyakon oceans, the Amerasia Basin and Panthalassa. Tomographic and geodynamic evidence for these oceans are found under present-day Greenland, Siberia and North America. The time-dependent models also suggest an alternative interpretation of the location and affinities of the “Farallon” and “Mongol-Okhotsk” slabs. A powerful outcome of geodynamic models is the evolution of dynamic topography. We suggest that at least 50% of the anomalously deep Argentine Basin can be attributed to long-lived, slab-driven negative dynamic topography. Similarly, for the Arctic, an evolving trend of subsidence from at least the Mid Jurassic to Early Cenozoic, followed by uplift or slowed subsidence to present-day is modelled. This signal is shown to partly account for vertical motions observed at the Barents Sea, Alaska and Slave Craton. This thesis shows that a careful consideration of absolute and relative plate reconstructions and modelling parameters, coupled with comparisons to seismic tomography and independent geological constraints, can provide key insights into the dynamic plate-mantle system.
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Frasson, Thomas. "Flux de chaleur hétérogène dans des simulations de convection mantellique : impact sur la géodynamo et les inversions magnétiques". Electronic Thesis or Diss., Université Grenoble Alpes, 2024. http://www.theses.fr/2024GRALU027.
Testo completoAbstract (sommario):
Le champ magnétique terrestre est généré par la convection du fer liquide dans le noyau, éléctriquementconducteur, produisant un effet dynamo. Ce processus, appelé géodynamo, maintientun champ magnétique depuis des milliards d’années. Les données paléomagnétiques montrent quele comportement de la géodynamo a changé au cours des temps géologiques. Ces changementsde comportement sont visibles à travers les variations de l’amplitude et de la stabilité du dipôlemagnétique. Les variations du flux de chaleur à la limite entre le noyau et le manteau (CMB) duesà la convection mantellique ont été suggérées comme un mécanisme capable d’entraîner un telchangement de comportement.Les modèles numériques de convection mantellique et de la géodynamo ont connu des améliorationssignificatives ces dernières années. Le couplage entre ces deux types de modèle peutdonner des indications sur la façon dont la géodynamo réagit aux variations de flux de chaleurà la CMB. Notre compréhension actuelle de ce couplage entre le manteau et le noyau est néanmoinsrestreinte par les limitations des modèles numériques. Du côté du manteau, l’orientationdu manteau par rapport à l’axe de rotation doit être mieux contrainte afin d’exploiter les récentessimulations reproduisant environ 1 Gyr de convection mantellique. Pour contraindre cette orientation,l’axe de plus grand moment d’inertie du manteau doit être aligné avec l’axe de rotation de laTerre, ce qui provoque des rotations du manteau appelées "true polar wander" (TPW). Du côté dunoyau, les simulations numériques sont encore loin du régime de paramètre de la Terre, et il n’estpas certain que le mécanisme d’inversion observé dans ces modèles soit pertinent pour le noyaude la Terre.Ce travail vise à mieux contraindre la façon dont les hétérogénéités de flux de chaleur à laCMB affectent la géodynamo. Dans une première partie, nous explorons l’impact du TPW surle flux de chaleur à la CMB en utilisant deux modèles de convection mantellique récemmentpubliés : un modèle contraint par une reconstruction de plaque et un second produisant de manièreautocohèrente un comportement de tectonique des plaques. Le géoïde est calculé pour corriger leTPW. Une alternative à la correction du TPW est utilisée pour le modèle contraint par la positiondes plaques en repositionnant simplement le manteau dans le référentiel paléomagnétique. Dansce modèle, l’axe de plus grand moment d’inertie n’est pas cohérent avec la position du dipôlemagnétique déduite du paléomagnétisme. Le TPW joue un rôle important dans la redistributiondu flux de chaleur, notamment à des échelles de temps courtes (≤ 10 Myr). Ces variations rapidesmodifient la distribution latitudinale du flux de chaleur à la CMB. Une analyse en composantesprincipales est effectuée pour obtenir les motifs de flux de chaleur dominant dans les modèles.Dans une deuxième partie, nous étudions l’impact des conditions hétérogènes de flux de chaleurau sommet du noyau dans des modèles de géodynamo qui s’étendent vers des régimes deparamètres plus proches de celui de la Terre que ce qui a été fait précédemment. L’effet de ladistribution du flux de chaleur en latitude est notamment étudié. Des motifs de flux complexes extraitsdes modèles de convection mantellique sont également utilisés. Nous montrons qu’un refroidissementéquatorial du noyau est le plus efficace pour déstabiliser le dipôle magnétique, tandisqu’un refroidissement polaire tend à stabiliser le dipôle. Les effets observés des flux de chaleurhétérogènes s’expliquent par la compatibilité entre les motifs de flux et les écoulements zonaux.Notamment, les motifs de flux de chaleur ont un effet plus modéré lorsque les écoulements zoiinaux vers l’ouest sont forts, avec une déstabilisation du dipôle seulement pour des amplitudesimprobables. Un paramètre contrôlant l’amplitude et la stabilité du dipôle magnétique, cohérentavec l’existence d’inversions magnétiques pour la Terre, est proposéThe Earth’s magnetic field is generated within the Earth’s core, where convective motions ofthe electrically conducting liquid iron result in a dynamo action. This process, called the geodynamo,has been maintaining a magnetic field for billion of years. Paleomagnetic evidence showsthat the behaviour of the geodynamo has changed during geological times. These behaviourchanges are visible through variations in the strength and stability of the magnetic dipole. Variationsin the heat flux at the core-mantle boundary (CMB) due to mantle convection have beensuggested as one possible mechanism capable of driving such a change of behaviour.Numerical models of mantle convection and of the geodynamo have made significant improvementsin the recent years. Coupling mantle convection models and geodynamo models cangive insights into how the geodynamo reacts to variations in the CMB heat flux. Our current understandingof this thermal coupling between the mantle and the core is nonetheless restricted bylimitations in numerical models on both the mantle and core side. On the mantle side, the orientationof the mantle with respect to the spin axis has to be better constrained in order to exploitrecent simulations reproducing about 1 Gyr of mantle convection. Constraining this orientationrequires to align the maximum inertia axis of the mantle with the spin axis of the Earth, causingsolid-body rotations of the mantle called true polar wander (TPW). On the core side, numericalsimulations are still far from the parameter regime of the Earth, and it is not clear whether thereversing mechanism observed in these models is relevant for the Earth’s core.This work aims at acquiring a more complete understanding of how lateral heterogeneitiesof the CMB heat flux affect the geodynamo. In a first part, we explore the impact of TPW onthe CMB heat flux using two recently published mantle convection models: one model drivenby a plate reconstruction and a second that self-consistently produces a plate-like behaviour. Wecompute the geoid in both models to correct for TPW. An alternative to TPW correction is used forthe plate-driven model by simply repositioning the model in the original paleomagnetic referenceframe of the plate reconstruction. We find that in the plate-driven mantle convection model, themaximum inertia axis does not show a long-term consistency with the position of the magneticdipole inferred from paleomagnetism. TPW plays an important role in redistributing the CMBheat flux, notably at short time scales (≤ 10 Myr). Those rapid variations modify the latitudinaldistribution of the CMB heat flux. A principal component analysis (PCA) is computed to obtainthe dominant CMB heat flux patterns in the models.In a second part, we study the impact of heterogeneous heat flux conditions at the top of thecore in geodynamo models that expands towards more Earth-like parameter regimes than previouslydone. We especially focus on the heat flux distribution between the poles and the equator.More complex patterns extracted from the mantle convection models are also used. We show thatan equatorial cooling of the core is the most efficient at destabilizing the magnetic dipole, while apolar cooling of the core tends to stabilize the dipole. The observed effects of heterogeneous heatflux patterns are explained through the compatibility of thermal winds generated by the heat fluxpattern with zonal flows. Notably, heat flux patterns have a more moderate effect when westwardzonal flows are strong, with a destabilization of the dipole only for unrealistically large amplitudes.A parameter controlling the strength and stability of the magnetic dipole that is consistentwith the reversing behaviour of the geodynamo is suggested.i
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Boukaré, Charles-Edouard. "Dynamique du manteau dans la jeune Terre". Thesis, Lyon, 2016. http://www.theses.fr/2016LYSE1011/document.
Testo completoAbstract (sommario):
Dans les premiers instants de l'histoire des planètes telluriques, la chaleur d'accrétion, le chauffage radioactif et la différenciation noyau-manteau apparaissent comme des sources d'énergie capables de fondre le manteau terrestre significativement. L'évolution d'un océan de magma suite à ces évènements catastrophiques dépend des propriétés physiques des matériaux silicatés en conditions mantelliques et de la dynamique convective complexe d'un manteau en cristallisation. Actuellement, certains auteurs proposent que la structure actuelle du manteau profond pourrait être associée à des reliques de la cristallisation d'un océan de magma primitif. Nous avons développé un modèle thermodynamique capable de modéliser de façon auto cohérente des séquences de cristallisation dans les conditions du manteau profond. A partir de ce modèle, nous avons montré que le magma s'enrichit progressivement en fer au cours de la cristallisation. Le liquide résiduel devient ainsi plus dense que la phase solide. Ce modèle thermodynamique suggère un scénario de cristallisation de l'océan de magma similaire à celui proposé par (Labrosse et al., 2007). Celui-ci prédit que la structure actuelle de la base du manteau hériterait de la cristallisation d'un océan de magma primitif. Afin d'étudier l'influence de ce contraste de densité et des profils de liquidus sur la dynamique syn- cristallisation d'un océan de magma, nous avons développé un code de convection multiphasique intégrant changement phase, percolation / compaction et cristallisation fractionnée. Dans ce mémoire, nous présentons des modèles dynamiques préliminaires de cristallisation dans le cas univariantEarly in the history of terrestrial planet, heat of accreation, radioactive deacay and core-mantle segratation may have melted the silicate mantle significantly. Magma ocean evolution depends on both physical properties of materials at relevant P-T conditions and the complex dynamics of a convecting cristallizing mantle. Present deep Earth mantle structures might be direclty linked to the crystallization of a potential magma ocean. We propose a complete thermodynamic model of the solid-liquid equilibrium in the MgO-FeO-SiO2 system which allows to compute self-consistenltly crystallization sequence at deep mantle conditions. The present study shows that, at thermodynamic equilibrium, the first solids that crystallize in the deep mantle are lighter than the liquid as they are more Mg-rich. This further enriches the melt in iron and this residual melt becomes much denser than the solid phase. Both the anti-freeze effect of iron and its high density suggest a mantle crystallization scenario similar to that described in Labrosse et al. (2007) where the ULVZ are iron rich and very fusible remnants of a primordial basal magma ocean. In addition, we have developped a multiphase convection code accounting for solid-liquid phase change, compaction and fractionnal cristallization. This mechanical model is dedicated to the investigation of the effects of various temperature profile and solid liquid density cross-overs on the dynamics of a cristallizing mantle. In this thesis, we show preliminary models illustrating the effect of chemical density contrasts between melt and solid in the case of univariant crystallization
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Li, Huijuan. "Apatite as an indicator of fluid salinity in subduction zone settings : implications for the deep earth chlorine cycle". Phd thesis, 2012. http://hdl.handle.net/1885/149863.
Testo completoAbstract (sommario):
In search of a parameter to monitor the variation in the salinity of subduction zone fluids, piston-cylinder experiments have been conducted to investigate chlorine partitioning behaviour in subducted sediment systems at subduction zone conditions. Apatite was found to be a prime candidate for monitoring fluid Cl content, as it represents the most chlorine rich phase. Chlorine partition coefficients between apatite and melt/aqueous fluid (DCl) show a general increase with increasing temperature, and a decrease with increasing pressure. DCl values were found to be negatively correlated with the bulk F concentration/ F contents in apatite; this was attributed to non-ideal mixing of F-Cl and F-OH in apatite. A thermodynamic framework was developed and applied to describe the OH-Cl-F exchange equilibrium between apatite and melt. Ideal mixing for the binary Cl-OH apatite solution is valid for the investigated P and T range of 2.5-4.5 GPa and 600-900 degree C. Through least square linear regression of our experimental data, values for the interaction parameters W^{Ap}F-Cl and W^{Ap}F-OH were determined. Combining all derived thermodynamic data yields an equation to express melt Cl content (wt%) as a function of pressure, temperature and apatite composition.
This expression (27) in addition to measured Cl partition coefficients was utilized to calculate the salinity of fluids in equilibrium with selected natural samples. Case studies of apatites from subducted oceanic sediment samples and UHP metapelites from the Dora Maira and Kokchetav massifs demonstrate that aqueous fluids present during prograde subduction have low element mobility, and a low salinity that is << seawater salinity. Conversely, hydrous melts display salinities which are (equivalent or higher than){u2265} seawater salinity, which further enhances their trace element uptake. According to the determination of trace element concentrations in glasses from our 2.5 GPa, 800 degree C experiments, the F and Cl content in the melt increased the concentrations of REE, Th, U, Y, Zn, Sc and Mn, had no effect on Ti, Zr, Hf, P, Sr and LILE; while the concentrations of Nb and Ta were found to decrease. Therefore our study suggests that the presence of F and Cl in melt can contribute to the fractionation of REE/LFSE relative to HFSE during subduction recycling.
Our experiments indicate that the addition of fluid with seawater equivalent salinity does not produce a significant change in the phase and melting relations compared to the F, Cl-free system. Apatite appears incapable of fractionating the H{u2082}O/Cl ratio in either aqueous fluid or hydrous melt even though it possesses a high Cl/H{u2082}O ratio. The extensive variation in the H{u2082}O/F fluid ratio suggests that hydrous minerals present in the slab residue have the potential to fractionate H{u2082}O and Cl from F in subduction fluids. -- provided by Candidate.
Libri sul tema "Deep Earth dynamics"
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E, Smylie D., Hide R. 1929-, International Union of Geodesy and Geophysics, American Geophysical Union e All Union Symposium U2 on 'Instability within the Earth and Core Dynamics' (1987 : Vancouver, B.C.), a cura di. Structure and dynamics of earth's deep interior. Washington, DC: American Geophysical Union, 1987.
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Le Mouël, J. L., D. E. Smylie e T. Herring, a cura di. Dynamics of Earth's Deep Interior and Earth Rotation. Washington, D. C.: American Geophysical Union, 1993. http://dx.doi.org/10.1029/gm072.
Testo completo
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L, Le Mouël J., Smylie D. E e Herring T, a cura di. Dynamics of earth's deep interior and earth rotation. Washington, DC: American Geophysical Union, 1993.
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Structure and dynamics of earth's deep interior. Washington, DC: American Geophysical Union, 1988.
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Hide, Raymond, e D. E. Smylie. Structure and Dynamics of Earth's Deep Interior. Wiley & Sons, Limited, John, 2013.
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J. -L Le Mouël, T. Herring e D. E. Smylie. Dynamics of Earth's Deep Interior and Earth Rotation. Wiley & Sons, Limited, John, 2013.
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Kelly, Piers. The Last Language on Earth. Oxford University Press, 2022. http://dx.doi.org/10.1093/oso/9780197509913.001.0001.
Testo completoAbstract (sommario):
The Eskayan language of Bohol in the southern Philippines has been an object of controversy ever since it came to light in the early 1980s. Written in an unusual script, Eskayan bears no obvious similarity to any known language of the Philippines, a fact that has prompted speculation that it was either displaced from afar, fossilized from the deep past, or invented as an elaborate hoax. This book investigates the history of Eskayan through a systematic review of its writing system, grammar, and lexicon and carefully evaluates written and oral narratives provided by its contemporary speakers. The linguistic analysis largely supports the traditional view that Eskayan was the deliberate creation of a legendary ancestor by the name of Pinay. The study traces the identity of Pinay through the turbulent history of early twentieth-century Bohol when the island suffered a series of catastrophes at the hands of the United States occupation. It was at this time that the ancestor Pinay was channeled by Mariano Datahan, a multilingual prophet who foretold that English and other languages would be abandoned and that Eskayan would one day be spoken by everyone in the world. To make sense of this situation, the book draws on theorizations of postcolonial resistance, language ideology, mimesis, and the utopian political dynamics of highland societies. In so doing, it offers a linguistic and ethnographic history of Eskayan and of the ideologies and historical circumstances that motivated its creation.
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Steinberg, Paul F. Who Rules the Earth? Oxford University Press, 2015. http://dx.doi.org/10.1093/oso/9780199896615.001.0001.
Testo completoAbstract (sommario):
Worldwide, half a million people die from air pollution each year-more than perish in all wars combined. One in every five mammal species on the planet is threatened with extinction. Our climate is warming, our forests are in decline, and every day we hear news of the latest ecological crisis. What will it really take to move society onto a more sustainable path? Many of us are already doing the "little things" to help the earth, like recycling or buying organic produce. These are important steps-but they're not enough. In Who Rules the Earth?, Paul Steinberg, a leading scholar of environmental politics, shows that the shift toward a sustainable world requires modifying the very rules that guide human behavior and shape the ways we interact with the earth. We know these rules by familiar names like city codes, product design standards, business contracts, public policies, cultural norms, and national constitutions. Though these rules are largely invisible, their impact across the planet has been dramatic. By changing the rules, Ontario, Canada has cut the levels of pesticides in its waterways in half. The city of Copenhagen has adopted new planning codes that will reduce its carbon footprint to zero by 2025. In the United States, a handful of industry mavericks designed new rules to promote greener buildings, and transformed the world's largest industry into a more sustainable enterprise. Steinberg takes the reader on a series of journeys, from a familiar walk on the beach to a remote village deep in the jungles of Peru, helping the reader to "see" the social rules that pattern our physical reality and showing why these are the big levers that will ultimately determine the health of our planet. By unveiling the influence of social rules at all levels of society-from private property to government policy, and from the rules governing our oceans to the dynamics of innovation and change within corporations and communities-Who Rules the Earth? is essential reading for anyone who understands that sustainability is not just a personal choice, but a political struggle.
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Karato, Shun-Ichiro. The Dynamic Structure of the Deep Earth: An Interdisciplinary Approach. Princeton University Press, 2003.
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The dynamic structure of the deep Earth: An interdisciplinary approach. Princeton, N.J: Princeton University Press, 2003.
Cerca il testo completoCapitoli di libri sul tema "Deep Earth dynamics"
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Zhao, Dapeng. "Global Tomography and Deep Earth Dynamics". In Multiscale Seismic Tomography, 215–68. Tokyo: Springer Japan, 2015. http://dx.doi.org/10.1007/978-4-431-55360-1_7.
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Anderson, Rika E., William J. Brazelton e John A. Baross. "20. The Deep Viriosphere: Assessing the Viral Impact on Microbial Community Dynamics in the Deep Subsurface". In Carbon in Earth, a cura di Robert M. Hazen, Adrian P. Jones e John A. Baross, 649–76. Berlin, Boston: De Gruyter, 2013. http://dx.doi.org/10.1515/9781501508318-022.
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Valencia, Diana. "Composition and Internal Dynamics of Super-Earths". In Physics and Chemistry of the Deep Earth, 271–94. Chichester, UK: John Wiley & Sons, Ltd, 2013. http://dx.doi.org/10.1002/9781118529492.ch9.
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Hinderer, Jacques, e David Crossley. "Core Dynamics and Surface Gravity Changes". In Dynamics of Earth's Deep Interior and Earth Rotation, 1–16. Washington, D. C.: American Geophysical Union, 2013. http://dx.doi.org/10.1029/gm072p0001.
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Szeto, Anthony M. K. "Inner Core Motions: Implications on Earth Rotation". In Dynamics of Earth's Deep Interior and Earth Rotation, 31–33. Washington, D. C.: American Geophysical Union, 2013. http://dx.doi.org/10.1029/gm072p0031.
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Jamet, Quentin, Etienne Mémin, Franck Dumas, Long Li e Pierre Garreau. "Toward a Stochastic Parameterization for Oceanic Deep Convection". In Mathematics of Planet Earth, 143–57. Cham: Springer Nature Switzerland, 2023. http://dx.doi.org/10.1007/978-3-031-40094-0_6.
Testo completoAbstract (sommario):
AbstractCurrent climate models are known to systematically overestimate the rate of deep water formation at high latitudes in response to too deep and too frequent deep convection events. We propose in this study to investigate a misrepresentation of deep convection in Hydrostatic Primitive Equation (HPE) ocean and climate models due to the lack of constraints on vertical dynamics. We discuss the potential of the Location Uncertainty (LU) stochastic representation of geophysical flow dynamics to help in the process of re-introducing some degree of non-hydrostatic physics in HPE models through a pressure correction method. We then test our ideas with idealized Large Eddy Simulations (LES) of buoyancy driven free convection with the CROCO modeling platform. Preliminary results at LES resolution exhibit a solution obtained with our Quasi-nonhydrostatic (Q-NH) model that tends toward the reference non-hydrostatic (NH) model. As compared to a pure hydrostatic setting, our Q-NH solution exhibits vertical convective plumes with larger horizontal structure, a better spatial organization and a reduced intensity of their associated vertical velocities. The simulated Mixed Layer Depth (MLD) deepening rate is however too slow in our Q-NH experiment as compared to the reference NH, a behaviour that opposes to that of hydrostatic experiments of producing too fast MLD deepening rate. These preliminary results are encouraging, and support future efforts in the direction of enriching coarse resolution, hydrostatic ocean and climate models with a stochastic representation of non-hydrostatic physics.
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Aldridge, Keith D., e W. H. Cannon. "A Search for Evidence of Short Period Polar Motion in VLBI and Supergravimetry Observations". In Dynamics of Earth's Deep Interior and Earth Rotation, 17–24. Washington, D. C.: American Geophysical Union, 2013. http://dx.doi.org/10.1029/gm072p0017.
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Cummins, Phil R., e John M. Wahr. "IDA Tidal Data and the Earth's Nearly Diurnal Free Wobble". In Dynamics of Earth's Deep Interior and Earth Rotation, 25–30. Washington, D. C.: American Geophysical Union, 2013. http://dx.doi.org/10.1029/gm072p0025.
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Dehant, V., B. Ducarme e P. Defraigne. "New Analysis of the Superconducting Gravimeter Data of Brussels". In Dynamics of Earth's Deep Interior and Earth Rotation, 35–44. Washington, D. C.: American Geophysical Union, 2013. http://dx.doi.org/10.1029/gm072p0035.
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Lefftz, Marianne, e Hilaire Legros. "Variation of J2 and Internal Loads". In Dynamics of Earth's Deep Interior and Earth Rotation, 45–49. Washington, D. C.: American Geophysical Union, 2013. http://dx.doi.org/10.1029/gm072p0045.
Testo completoAtti di convegni sul tema "Deep Earth dynamics"
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Papasergio, Antonia, Yuan Mei e Fang Huang. "Molecular dynamics insights of NaCl-bearing fluids at deep-Earth conditions". In Goldschmidt2022. France: European Association of Geochemistry, 2022. http://dx.doi.org/10.46427/gold2022.9225.
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Kannangara, KATT, MB Shoukie, MPA Nayomi, SM Dassanayake, ABN Dassanyake e CL Jayawardena. "Determining the Invasive Plant Dynamics in Bolgoda Lake Using Open-source Data". In International Symposium on Earth Resources Management & Environment. Department of Earth Resources Engineering, University of Moratuwa, Sri Lanka, 2022. http://dx.doi.org/10.31705/iserme.2022.15.
Testo completoAbstract (sommario):
Identifying invasive plants (IP) and monitoring their dynamics is essential to minimize potential adverse effects on natural resources. Remote sensing (RS) could effectively cater to such requirements by acquiring data in many critical domains. Limitations of spatial resolution, spectral information, and large imagery files usually hinder retrieving, managing, and analyzing remotely sensed data. The cloud-based computational capabilities of Google Earth Engine (GEE) provide the amenities for geospatial data analysis, retrieval, and processing with access to a majority of freely available, public, multi-temporal RS data. Integrating machine learning algorithms into GEE generates a promising path toward operationalizing automated RS-based IP monitoring by overcoming traditional challenges. Use of Classification and Regression Trees (CART) classifier to generate water-vegetation classification over six years (2016-2021) with Landsat 8 and Sentinel 2 images enabled mapping the invasive plants and their dominant component of Water Hyacinth (Pontederia crassipes) across a heterogeneous landscape in Bolgoda Lake, Sri Lanka. Also, the study could develop a relatively accurate classification of the water-vegetation dynamics over the time of interest. The classified time series data indicates the annual variation of the water, vegetation, and non-vegetation classes with rapidly fluctuating seasonal cycles for the vegetation cover. These results could benefit regulatory authorities and institutions to optimize environmental resource management and prioritize eco-preservation attempts. Moreover, the findings reflect the capabilities of deep learning models to identify invasive plant behaviors even with modest spatial and spectral resolution imagery.
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Wittmann, M., M. T. Wick, G. Korn, J. Ringling e E. Matthias. "Subpicosecond Carrier Relaxation Dynamics and Defect Formation in Wide-Band-Gap Materials". In The European Conference on Lasers and Electro-Optics. Washington, D.C.: Optica Publishing Group, 1998. http://dx.doi.org/10.1364/cleo_europe.1998.cwf57.
Testo completoAbstract (sommario):
Alkaline-earth fluorides are widely used in optical transmission components in the deep UV as well as for optical coatings because of their wide-band-gap, low refractive indices and hardness. One essential drawback of these materials is the formation of defects (color centers e. g.) during intense irradiation. This limits the lifetime of such optical elements for high power propagation in the UV and reduces the transmission of ultrashort laserpulses nonlinearly. Details of this process, in particular the dynamics during the early stages (formation of self-trappped excitons STE [1]) are therefor of interest.
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Dombovari, Zoltan, e Gabor Stepan. "Dynamics of Drill Bits With Cutting Edges of Varying Parameters". In ASME 2013 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/detc2013-12594.
Testo completoAbstract (sommario):
In the metal cutting industry it is well known that milling processes can be stabilized by applying different strategies in order to destroy the pure single delay regeneration that arise in case of conventional milling tools when high material removal rates are used either at low or at high cutting speeds. To achieve this goal, variable pitch angle, variable helix angle and serrated tools are already available in the market and serve alternative solutions for process designers to enhance milling process stability. Regeneration can occur and can cause instability on the tip of the deep drilling equipment when the drill bit is driven across hard earth crust materials. This work shows that theories introduced for milling processes can be implemented to improve the stability properties of deep drilling processes, too. Unlike in case of most milling processes, however, the stability properties of deep drilling are affected by the longitudinal and the torsional vibration modes. In this paper, the geometrical and mechanical models are derived for drill bits with general shapes of cutting edges and it is shown that the two DOF dynamics can be described by distributed state dependent delay differential equations. The stability properties are characterized in stability diagrams that can help to select the optimal drilling process parameters.
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Ahn, H., M. Grimes, Y. S. Lee e M. C. Downer. "Quantitative Dielectric Properties of Solid Density Plasmas Measured by Femtosecond Ellipsometry". In High Resolution Fourier Transform Spectroscopy. Washington, D.C.: Optica Publishing Group, 1994. http://dx.doi.org/10.1364/hrfts.1994.we2.
Testo completoAbstract (sommario):
Intense (1012 - 1014 W/cm2) femtosecond laser pulses create deep earth pressure-temperature conditions at a solid surface before hydrodynamic surface expansion occurs1. Photoexcitation of carbon, silicon, and germanium from melting fluence Fm up to approximately 30 Fm by femtosecond pulses induces a phase transition from their crystalline states to metallic liquid states within 1 ps followed by hydrodynamic surface expansion, with scale lengths much less than the incident probe wavelengths. Quantitative optical properties of the well-characterized fluid surfaces are determined by the time-resolved measurement of s- and p-polarized reflectivity at variable probe incident angles and excitation fluences, and at two different probe wavelengths. The surface expanding dynamics in 20 ps as well as the subpicosecond risetimes of reflectivity responses are important for accurate determination of optical properties of liquid states of materials.
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Matsuo, Miki Y., Tomoya Inoue e Hide Sakaguchi. "Mathematical Analysis of Possible Range of Stable Drilling in Offshore Riserless Drilling System". In ASME 2017 36th International Conference on Ocean, Offshore and Arctic Engineering. American Society of Mechanical Engineers, 2017. http://dx.doi.org/10.1115/omae2017-62337.
Testo completoAbstract (sommario):
In both of scientific and industrial drilling, it is not desirable to any have accompanying vibrations, large fluctuations, or other unexpected dynamics disturbing a steady and stable drilling process. One of the origins of such disturbances can be the flexibility of the drill pile; drill pipe is easily deformed by external perturbations because it is very long and slender. To specify the stable range of parameters of drill pipe, we theoretically and numerically analyzed a Cosserat-type mathematical model of drill pile. The values of the parameters of this model were set to appropriate values representing actual riserless drilling situations adopted in the operations of the scientific deep-sea drilling vessel Chikyu owned by the Japan Agency for Marine-Earth Science and Technology (JAMSTEC). We concluded that the buckling of pipe should be treated as a possible accident, but buckling does not happen in the normal operations of the Chikyu.
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Gyimah, E., M. Metually, O. S. Tomomewo, J. P. Hurtado, M. Alamooti e W. Gosnold. "Geothermal Energy Storage: A Conceptual Assessment of Geologic Thermal Storage Systems in North Dakota". In 57th U.S. Rock Mechanics/Geomechanics Symposium. ARMA, 2023. http://dx.doi.org/10.56952/arma-2023-0390.
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ABSTRACT Geothermal energy and Aquifer thermal energy storage can provide beneficial ways of storing energy in excess and providing energy when needed. North Dakota's renewable energy system is impacted by its harsh winters. Geologic aquifer thermal aquifer storage system is a large scale geothermal system that can act as energy storage media. Aquifer thermal storage systems are dependent on heat conductivity of rocks, storage capacity of aquifer, fluid flow, geochemistry and geo-mechanics. The goals of the project are to 1) evaluate the amount of energy that can be stored in deep aquifers; 2) access the amount of energy that is thermally recoverable; 3) monitor changes in geo-mechanical parameters. CMG STARS, a three-phase multi-component thermal and steam additive simulator, was used for the thermal numerical simulation which takes into account the geo-mechanics (thermal dilation and re-compaction). A conventional reservoir with representative porosity and permeability is modelled in CMG and Semi Analytical Model (SAM) was used to calculate the wellbore dynamics involved with geothermal operations. This is used to calculate heat transfer to the surrounding formation and determine our heat loss. Our preliminary results show us the reservoir pore volume dilation re-compaction model changes from cold water injection. The grid block void porosity dilation re-compaction model changes are greatly influenced by grid block pressure. INTRODUCTION Geothermal Energy and Aquifer Thermal Energy Storage (ATES) Geothermal energy refers to the earth's thermal energy that can be converted into electrical energy. Emissions from the geothermal energy industry are substantially low, which is an excellent asset to reaching a low-carbon economy. Hot dry rocks and hydrothermal resources are the primary geothermal energy sources. Water from surface seeps through faults and cracks of earth and is warmed by hot rocks or water is trapped by impermeable layers to create geothermal reservoirs. Sedimentary basins have great geologic and reservoir properties for low-cost energy generation for geothermal energy. Hot water moves from deep sources to shallow reservoirs for hot water geothermal reservoirs. Hydrothermal systems use steam or water for electricity generation. Enhanced geothermal systems extract thermal energy from geothermal resources with lower permeability and fluid saturation. (Grant & Bixley, 2011)(Barbier, 2002)
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Ćosić, Said, e István Vokony. "Deep Learning-Based Dynamic State Estimation for Frequency Stability Monitoring in Power Systems with High Penetration of Renewable Generation". In International Conference on Electronics, Engineering Physics and Earth Science. Basel Switzerland: MDPI, 2023. http://dx.doi.org/10.3390/engproc2023041016.
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Panicucci, Paolo, Eleonora Andreis, Fabio Ornati e Francesco Topputo. "Towards Validation and Verification of Autonomous Vision-Based Navigation for Interplanetary Spacecraft". In ESA 12th International Conference on Guidance Navigation and Control and 9th International Conference on Astrodynamics Tools and Techniques. ESA, 2023. http://dx.doi.org/10.5270/esa-gnc-icatt-2023-112.
Testo completoAbstract (sommario):
Abstract The number of spacecraft launched per year is increased dramatically in the last decades granting access to private companies and public actors. Space assets are becoming crucial to asses disaster monitoring, precise agriculture, and global network interconnections. This trend is not limited to Earth observation applications, but it extends beyond Earth's orbit to support space exploration and exploitation. The current paradigm to operate interplanetary spacecraft strongly relies on the Deep-Space Network (DSN) which communicates with the spacecraft to obtain range and range-rate measurements. These data are then processed by large teams of engineers on ground to solve the orbit determination problem and the required maneuvers. Although this process is extremely precise and has been used since the beginning of space exploration, the increasing number of spacecraft and the riskier operations needed to support compelling science are making it outdated. First, the DSN has a limited number of communication slots which implies that a small number of spacecraft can be operated. Second, the process is extremely costly as large teams of individuals are involved in it. Finally, the delayed communications between the spacecraft and the ground station make some operations, such as landing or sampling, infeasible as the spacecraft does not have the needed reactivity. Because of these reasons, autonomous navigation is becoming a crucial technology for present and future missions. Among all the navigation sensors, cameras are generally preferred because they are light, compact, and low-priced. For this reason, Vision-Based Navigation (VBN), i.e., the combination of camera and image processing (IP) algorithms, is generally employed as an autonomous solution to solve the navigation problem. When a spacecraft is on an interplanetary cruise, it can determine its position by using known planet position within the Solar System. When the planet lines of sight (LoS) measurements are available, the spacecraft can triangulate its position in the inertial reference frame by knowing the planet ephemeris. This can be performed statically [1, 2], when more than one planet is available, or dynamically, by providing the LoSes measurements history to a navigation filter [3, 4]. The planet LoS determination can be performed by extracting the planet position from images by performing attitude determination and by knowing the planet ephemeris [5, 6]. This is a fully autonomous solution as the spacecraft does not require any piece of information from ground. The proposed solution is thus composed of an IP pipeline, which determines autonomously its attitude and extracts the planet LoSes, and a navigation filter, which determines the spacecraft state by taking into account light aberrations [7]. An important step to be performed is the algorithm validation process which is generally performed by increasing the simulation framework complexity and by including hardware-in-the-loop (HIL) components. Andreis et al. [4] develops and analyses the navigation filtering strategy to be deployed on board by assuming IP behavioral model, while Andreis et al. [6] and Andreis et al. [5] develop the IP pipeline and test it on synthetic images from a custom-designed rendering engine [8]. Andreis et al. [7] further develop the VBN algorithm by proposing an integrated solution to compensate for light aberrations. Finally, Panicucci et al. [9] assesses the IP performances on images acquired on RETINA, a HIL optical navigation test bench. In this context, a high-resolution screen stimulates a camera to acquire images as they would be taken in orbit. Standing on previous work, this paper presents the validation of the VBN algorithm on HIL simulation. First, a series of images are acquired on RETINA by simulating the reference trajectory and the attitude profile of the spacecraft. These images are processed sequentially by the VBN algorithm. Spacecraft state estimates are compared against the true value to assess navigation accuracy. Acknowledgments This research is part of EXTREMA, a project that has received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (Grant Agreement No. 864697). References [1] V. Franzese and F. Topputo. Optimal beacons selection for Deep-Space optical navigation. The Journal of the Astronautical Sciences, 67(4):1775–1792, 2020. doi: 10.1007/s40295-020-00242-z. [2] S. B. Broschart, N. Bradley, and S. Bhaskaran. Kinematic approximation of position accuracy achieved using optical observations of distant asteroids. Journal of Spacecraft and Rockets, 56 (5):1383–1392, 2019. doi: 10.2514/1.A34354. [3] R. R. Karimi and D. Mortari. Interplanetary autonomous navigation using visible planets. Journal of Guidance, Control, and Dynamics, 38(6):1151–1156, 2015. doi: 10.2514/1.G000575. [4] E. Andreis, V. Franzese, and F. Topputo. Onboard Orbit Determination for Deep-Space CubeSats. Journal of Guidance, Control, and Dynamics, pages 1–14, 2022. doi: 10.2514/1.G006294. [5] E. Andreis, P. Panicucci, and F. Topputo. An Image Processing Pipeline for Autonomous Deep-Space Optical Navigation. Journal of Spacecraft and Rockets, Under Review. [6] E. Andreis, P. Panicucci, V. Franzese, and F. Topputo. A Robust Image Processing Pipeline for Planets Line-Of-sign Extraction for Deep-Space Autonomous Cubesats Navigation. In 44th AAS Guidance, Navigation and Control Conference, pages 1–19, 2022. [7] E. Andreis, P. Panicucci, V. Franzese, and F. Topputo. A Vision-Based Navigation algorithm for Autonomous Deep-Space Cruise. In 3rd Space Imaging Workshop, 2022. [8] S. Bella, E. Andreis, V. Franzese, P. Panicucci, and F. Topputo. Line-of-Sight Extraction Algorithm for Deep-Space Autonomous Navigation. In 2021 AAS/AIAA Astrodynamics Specialist Conference, pages 1–18, 2021. [9] P. Panicucci, Andreis E., V. Franzese, and F. Topputo. An Overview of the EXTREMA Deep-Space Optical Navigation Experiment. In 3rd Space Imaging Workshop, 2022.
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Feng, Jianyun, Ying Zhang, Jun Luo, Yan Zeng, Xiaorui Yun, Dawei Liao, Zhiliang He et al. "Geological Analysis of Typical Geothermal Systems in East of China". In 58th U.S. Rock Mechanics/Geomechanics Symposium. ARMA, 2024. http://dx.doi.org/10.56952/arma-2024-0167.
Testo completoAbstract (sommario):
ABSTRACT: Eastern China, which lies to the east of the Hu Huanyong Line that connects the Heihe and Tengchong areas, has a high population density, a developed economy, and a huge demand for energy. To determine the geothermal resources in eastern China, this study analyzed the typical geothermal systems in this region based on disciplines of structural geology, and petrology. As a result, this study determined the distribution patterns of medium and deep geothermal resources in this region. Eastern China is a superimposed region of three major global tectonic domains, namely Paleo-Asia, Circum-Pacific, and Tethyan. Its crust-mantle structure presents a special flyover pattern, while its shallow surface has alternating basins and mountains and well-spaced uplifts and depressions. Studies have shown that medium-high-temperature geothermal resources in China are mainly distributed in the Mesozoic-Cenozoic basins in eastern China. However, they are dominated by medium-temperature geothermal resources with low abundance. The geothermal reservoir types mainly include porous sandstone reservoirs, karstified fractured-vuggy carbonate reservoirs, and fissured granite reservoirs. 1. INTRODUCTION Eastern China, which lies to the east of the Hu Huanyong Line that connects the Heihe and Tengchong areas, consists of Northeast China, North China, the middle and lower reaches of the Yangtze River, Southwest China, and South China from north to south, has a high population density, hosting 96% of the total population of China, as well as a developed economy and a huge demand for energy (Fig. 1). As an earth-derived energy source, geothermal resources are clean, renewable, and highly competitive and can be used for indoor heating, industrial and agricultural utilization, and power generation. The successive launch of national projects in China, such as the Deep Resource Exploration and Exploitation Program, began the exploration of the deep earth in China, and important achievements have been increasingly achieved in basic geology and geothermal geology. Moreover, research on deep-crust temperature and crust-mantle dynamic mechanisms has been gradually intensified (Shi 1990; Xu et al., 1995; He et al., 2001; An et al., 2007; Wang et al., 2012; Qiu et al., 2015). Remarkable progress has been made in research on terrestrial heat flow (Jiang et al., 2016, 2019), geothermal system types (Chen et al., 1996; Zhang et al., 2017), the division of geotectonic units and geothermal units (Pan et al., 2009; He et al., 2017), the selection and evaluation of optimal exploration areas (He et al., 2020; Zhang et al., 2020; Ke et al., 2022), hot dry rock development experiments (Wang et al., 2022), and geothermal applications (Wang et al., 2014), laying a solid foundation for the study of deep geothermal resources.
Rapporti di organizzazioni sul tema "Deep Earth dynamics"
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Balmforth, Neil J., e Colm-cille Caulfield. 2018 program of studies: sustainable fluid dynamics. Woods Hole Oceanographic Institution., 2023. http://dx.doi.org/10.1575/1912/67612.
Testo completoAbstract (sommario):
The 2018 GFD Program theme was Sustainable Fluid Dynamics with Professor Andrew Woods of the University of Cambridge serving as principal lecturer. Andy showed the audience in the cottage and on the porch how to find similarity solutions everywhere, from deep in the earth to high in the atmosphere. He expanded on his lectures with the fellows during “Andy time”, and stayed on throughout the summer to participate in the traditional debates on the porch with participants old and new. Andy also contributed enthusiastically to the supervision of the fellows, particularly when there was an opportunity to squirt food dye into an experiment.