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2010 | Book

Perpectives on Integrated Solid Earth Sciences Read chapter Read first chapter

New Frontiers in Integrated Solid Earth Sciences

Editors: S. Cloetingh, Jorg Negendank

Publisher: Springer Netherlands

Book Series : International Year of Planet Earth

Part of: Springer Professional "Wirtschaft+Technik" , Springer Professional "Technik"

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About this book

Man’s intensifying use of the Earth’s habitat has led to an urgent need for scientifically advanced ‘geo-prediction systems’ that accurately locate subsurface resources and forecast the timing and magnitude of earthquakes, volcanic eruptions and land subsidence.

As advances in the earth sciences lead to process-oriented ways of modeling the complex processes in the solid Earth, the papers in this volume provide a survey of some recent developments at the leading edge of this highly technical discipline. The chapters cover current research in predicting the future behavior of geologic systems as well as the mapping of geologic patterns that exist now in the subsurface as frozen evidence of the past. Both techniques are highly relevant to humanity’s need for resources such as water, and will also help us control environmental degradation.

The book also discusses advances made in seismological methods to obtain information on the 3D structure of the mantle and the lithosphere, and in the quantitative understanding of lithospheric scale processes. It covers recent breakthroughs in 3D seismic imaging that have enhanced the spatial resolution of these structural processes, and the move towards 4D imaging that measures these processes over time.

The new frontier in modern Earth sciences described in this book has major implications for oceanographic and atmospheric sciences and our understanding of climate variability. It brings readers right up to date with the research in this vital field.

Table of Contents

Frontmatter
Perpectives on Integrated Solid Earth Sciences
Abstract
During the last decades the Earth sciences are rapidly changing from largely descriptive to process-oriented disciplines that aim at quantitative models for the reconstruction and forecasting of the complex processes in the solid Earth. This includes prediction in the sense of forecasting the future behaviour of geologic systems, but also the prediction of geologic patterns that exist now in the subsurface as frozen evidence of the past. Both ways of prediction are highly relevant for the basic needs of humanity: supply of water and resources, protection against natural hazards and control on the environmental degradation of the Earth.
Intensive utilization of the human habitat carries largely unknown risks of and makes us increasingly vulnerable. Human use of the outermost solid Earth intensifies at a rapid pace. There is an urgent need for scientifically advanced “geo-prediction systems” that can accurately locate subsurface resources and forecast timing and magnitude of earthquakes, volcanic eruptions and land subsidence (some of those being man induced). The design of such systems is a major multidisciplinary scientific challenge. Prediction of solid-Earth processes also provides important constraints for predictions in oceanographic and atmospheric sciences and climate variability.
The quantitative understanding of the Earth has made significant progress in the last few decades. Important ingredients in this process have been the advances made in seismological methods to obtain information on the 3D structure of the mantle and the lithosphere, in the quantitative understanding of the lithospheric scale processes as well as the recognition of the key role of quantitative sedimentary basin analysis in connecting temporal and spatial evolution of the system Earth recorded in their sedimentary fill. Similar breakthroughs have been made in the spatial resolution of the structural controls on lithosphere and (de)formation processes and its architecture by 3D seismic imaging. Earth-oriented space research is increasingly directed towards obtaining a higher resolution in monitoring vertical motions at the Earth’s surface. Modelling of dynamic topography and landform evolution is reaching the phase where a full coupling can be made with studies of sediment supply and erosion in the sedimentary basins for different spatial and temporal scales.
Quantitative understanding of the transfer of mass at the surface by erosion and deposition as well as their feed back with crustal and subcrustal dynamics presents a new frontier in modern Earth sciences. This research bridges current approaches separately addressing high resolution time scales for a limited near surface record and the long term and large scale approaches characteristic so far for the lithosphere and basin-wide studies. The essential step towards a 4D approach (in space and time) is a direct response to the need for a full incorporation of geological and geophysical constraints, provided by both the quality of modern seismic imaging as well as the need to incorporate smaller scales in the modelling of solid Earth processes.
S.A.P.L. Cloetingh, J.F.W. Negendank
3D Crustal Model of Western and Central Europe as a Basis for Modelling Mantle Structure
Abstract
EuCRUST-07 is a new 3D model of the crust for western and central Europe. It offers a starting point in any kind of numerical modelling, which requires an a priori removal of the crustal effect. The digital model (35ºN, 71ºN; 25ºW, 35ºE) consists of three layers: sediments and two layers of the crystalline crust. The latter are characterized by average P-wave velocities (V p ), which were defined based on seismic data. The model was obtained by assembling together at uniform 15′×15′ grid available results of deep seismic reflection, refraction and receiver function studies. The Moho depth variations were reconstructed by merging the most robust and recent Moho depth maps existing for the European region and compiled using published interpretations of seismic profiles. EuCRUST-07 demonstrates large differences in Moho depth with previous compilations: over ±10 km in some specific areas (e.g., the Baltic Shield). The basement is outcropping in some part of eastern Europe, while in western Europe it is up to ∼16 km deep, with an average value of 3–4 km, reflecting the presence of relatively shallow basins. The velocity structure of the crystalline crust turns out to be much more heterogeneous than demonstrated in previous compilations, having an average V p varying from 6.0 to 6.9 km/s. In comparison to existing models, the new model shows average crustal velocity values distributed over a larger and continuous range. The sedimentary thickness appears underestimated by CRUST2.0 by ∼10 km in several basins (e.g., the Porcupine basin), while it is overestimated by ∼3–6 km along part of the coastline (e.g., the Norwegian coast). EuCRUST-07 shows a Moho 5–10 km deeper than previous models in the orogens (e.g., the Cantabrian Mountains) and in the areas where the presence of magmatic underplating increases anomalously the crustal thickness. EuCRUST-07 predicts a Moho shallower 10–20 km along parts of the Atlantic margin, and in the basin (e.g., the Tyrrhenian Sea), where previous models overestimate the average crustal velocity. Furthermore, the results of EuCRUST-07 are used to make inferences on the lithology for various parts of Europe. The new lithology map shows the eastern European tectonic provinces represented by a granite-felsic granulite upper crust and a mafic granulite lower crust. By contrast, the younger western European tectonic provinces are mostly characterized by an upper and lower crust of granite-gneiss and dioritic composition, respectively.
Magdala Tesauro, Mikhail K. Kaban, Sierd A.P.L. Cloetingh
Thermal and Rheological Model of the European Lithosphere
Abstract
A thermal and rheological model of the European lithosphere (10°W-35E; 35 N-60 N) is constructed based on a combination of new geophysical models. To determine temperature distribution a tomography model is used, which was improved by corrections for the crustal effect using a new digital model of the European crust (EuCRUST-07). The uppermost mantle under western Europe is generally characterized by temperatures ranging between 900 and 1,100°C, with the hottest areas corresponding to basins, that experienced recent extension (e.g., Tyrrhenian Sea and Pannonian Basin). By contrast, upper mantle temperatures at this depth under eastern Europe are about 550–750°C, whereby the lowest values are found in the northeastern part of the study area. EuCRUST-07 and the new thermal model are used to calculate the strength distribution within the European lithosphere. Differently from previous approaches, lateral variations of lithology and density derived from EuCRUST-07 are used to construct the new strength distribution model. Following the approach of Burov and Diament (1995), the lithospheric rheology is employed to calculate variations of the elastic thickness of the lithosphere. According to these estimates, in western Europe the lithosphere is more heterogeneous than in eastern Europe. Western Europe, with dominantly crust-mantle decoupling is mostly characterized by lower values of strength and elastic thickness. The crustal strength provides a large contribution to the integrated strength (∼50% of the integrated strength for the whole lithosphere) in most part of the study area (∼60%). The new results are important in view of recent disputes on the strength distribution between crust and mantle lithosphere.
Magdala Tesauro, Mikhail K. Kaban, Sierd A.P.L. Cloetingh
Thermo-Mechanical Models for Coupled Lithosphere-Surface Processes: Applications to Continental Convergence and Mountain Building Processes
Abstract
Simple mechanical considerations show that many tectonic-scale surface constructions, such as mountain ranges that exceed certain critical height (about 3 km in altitude, depending on rheology and width) should flatten and collapse within few My as a result of gravitational spreading that may be enhanced by flow in the ductile part of the crust. The elevated topography is also attacked by surface erosion that, in case of static topography, would lead to its exponential decay on a time scale of less than 2.5 My. However, in nature, mountains or rift flanks grow and stay as localized tectonic features over geologically important periods of time (>10 My). To explain the long-term persistence and localized growth of, in particular, mountain belts, a number of workers have emphasized the importance of dynamic feedbacks between surface processes and tectonic evolution. Surface processes modify topography and redistribute tectonically significant volumes of sedimentary material, which acts as vertical loading over large horizontal distances. This results in dynamic loading and unloading of the underlying crust and mantle lithosphere, whereas topographic contrasts are required to set up erosion and sedimentation processes. Tectonics therefore could be a forcing factor of surface processes and vice versa. One can suggest that the feedbacks between tectonic and surface processes are realised via 2 interdependent mechanisms: (1) slope, curvature and height dependence of the erosion/deposition rates; (2) surface load-dependent subsurface processes such as isostatic rebound and lateral ductile flow in the lower or intermediate crustal channel. Loading/unloading of the surface due to surface processes results in lateral pressure gradients, that, together with low viscosity of the ductile crust, may permit rapid relocation of the matter both in horizontal and vertical direction (upward/downward flow in the ductile crust). In this paper, we overview a number of coupled models of surface and tectonic processes, with a particular focus on 3 representative cases: (1) slow convergence and erosion rates (Western Alpes), (2) intermediate rates (Tien Shan, Central Asia), and (3) fast convergence and erosion rates (Himalaya, Central Asia).
E. Burov
Achievements and Challenges in Sedimentary Basin Dynamics: A Review
Abstract
Thanks to a continuous effort for unravelling geological records since the early days of coal and petroleum exploration and water management, the architecture and chrono-litho-stratigraphy of most sedimentary basins has been accurately described by means of conventional geological and geophysical studies, using both surface (outcrops) and subsurface (exploration wells and industry seismic reflection profiles) data. However, the understanding of the early development and long term evolution of sedimentary basins usually requires the integration of even more data on the deep Earth, as well as quantifications by means of kinematic-sedimentological and thermo-mechanical modelling approaches coupling both surface and deep processes.
In the last twenty years, huge national and international efforts, frequently linking academy and industry, have been devoted to the recording of deep seismic profiles in many intracratonic sedimentary basins and offshore passive margins, thus providing a direct control on the structural configuration of the basement and the architecture of the crust. Seemingly, needs for documenting also the current thickness of the mantle lithosphere and the fate of subducted lithospheric slabs have led to the development of more academic and new tomographic techniques. When put together, these various techniques now provide a direct access to the bulk 3D architecture of sedimentary basins, crystalline basement and Moho, as well as underlying mantle lithosphere.
Inherited structures, anisotropies in the composition of the sediments, crust and underlying mantle as well as thermicity and phase transitions are now taken into account when predicting the localization of deformation in the lithosphere during compression and extension episodes, and reconstructing the geodynamic evolution of rift basins, passive margins or even foreland fold-and-thrust belts.
Source to sink studies also provide accurate estimates of sedimentary budget at basin-scale. Extensive use of low temperature chrono-thermometers and coupled kinematic, sedimentological and thermal models allow a precise control on the amount and timing of erosion and unroofing of source areas, but also the reconstruction of the sedimentary burial, strata architecture and litho-facies distribution in the sink areas.
Coupling deep mantle processes with erosion and climate constitutes a new challenge for understanding the present topography, morphology and long term evolution of continents, especially in such sensitive areas as the near shore coastal plains, low lands and intra-mountain valleys which may be subject to devastating flooding and landslides.
In addition to the search for hydrocarbon resources, other societal needs such as CO2 storage and underground water management will benefit from upgraded basin modelling techniques. New 2D and 3D basin modelling tools are progressively developed, coupling in different ways deep thermo-mechanic processes of the mantle (asthenosphere and lithosphere), geomechanics of the upper crust and sediments (compaction, pressure-solution and fracturing of seals and reservoirs), basin-scale fluid and sediment transfers (development of overpressures, hydrocarbon generation and migration). Further challenges related to CO2 storage will soon require the integration of fluid-rock interactions (reactive transport) in basin and reservoir models, in order to cope with the changes induced by diagenesis in the overall mechanical properties, and the continuous changes in fluid flow induced by compaction, fracturing and cementation.
François Roure, Sierd Cloetingh, Magdalena Scheck-Wenderoth, Peter A. Ziegler
Recent Developments in Earthquake Hazards Studies
Abstract
In recent years, there has been great progress understanding the underlying causes of earthquakes, as well as forecasting their occurrence and preparing communities for their damaging effects. Plate tectonic theory explains the occurrence of earthquakes at discrete plate boundaries, such as subduction zones and transform faults, but diffuse plate boundaries are also common. Seismic hazards are distributed over a broad region within diffuse plate boundaries. Intraplate earthquakes occur in otherwise stable crust located far away from any plate boundary, and can cause great loss of life and property. These earthquakes cannot be explained by classical plate tectonics, and as such, are a topic of great scientific debate. Earthquake hazards are determined by a number of factors, among which the earthquake magnitude is only one factor. Other critical factors include population density, the potential for secondary hazards, such as fire, landslides and tsunamis, and the vulnerability of man-made structures to severe strong ground motion. In order to reduce earthquake hazards, engineers and scientists are taking advantage of new technologies to advance the fields of earthquake forecasting and mitigation. Seismicity is effectively monitored in many regions with regional networks, and world seismicity is monitored by the Global Seismic Network that consists of more than 150 high-quality, broadband seismic stations using satellite telemetry systems. Global Positioning Satellite (GPS) systems monitor crustal strain in tectonically active and intraplate regions. A relatively recent technology, Interferometric Synthetic Aperture Radar (InSAR) uses radar waves emitted from satellites to map the Earth’s surface at high (sub-cm) resolution. InSAR technology opens the door to continuous monitoring of crustal deformation within active plate boundaries. The U.S. Geological Survey (USGS), along with other partners, has created ShakeMap, an online notification system that provides near-real-time post-earthquake maps of ground shaking intensity. These maps are especially useful for the coordination of emergency response teams and for the improvement of building codes. Using a combination of these new technologies, with paleoseismology studies, we have steadily improved the science of earthquake forecasting whereby one estimates the probability that an earthquake will occur during a specified time interval. A very recent development is Earthquake Early Warning, a system that will provide earthquake information within seconds of the initial rupture of a fault. These systems will give the public some tens of seconds to prepare for imminent earthquake strong ground motion. Advances in earthquake science hold the promise of diminishing earthquake hazards on a global scale despite ever-increasing population growth.
Walter D. Mooney, Susan M. White
Passive Seismic Monitoring of Natural and Induced Earthquakes: Case Studies, Future Directions and Socio-Economic Relevance
Abstract
An important discovery in crustal mechanics has been that the Earth’s crust is commonly stressed close to failure, even in tectonically quiet areas. As a result, small natural or man-made perturbations to the local stress field may trigger earthquakes. To understand these processes, Passive Seismic Monitoring (PSM) with seismometer arrays is a widely used technique that has been successfully applied to study seismicity at different magnitude levels ranging from acoustic emissions generated in the laboratory under controlled conditions, to seismicity induced by hydraulic stimulations in geological reservoirs, and up to great earthquakes occurring along plate boundaries. In all these environments the appropriate deployment of seismic sensors, i.e., directly on the rock sample, at the earth’s surface or in boreholes close to the seismic sources allows for the detection and location of brittle failure processes at sufficiently low magnitude-detection threshold and with adequate spatial resolution for further analysis. One principal aim is to develop an improved understanding of the physical processes occurring at the seismic source and their relationship to the host geologic environment. In this paper we review selected case studies and future directions of PSM efforts across a wide range of scales and environments. These include induced failure within small rock samples, hydrocarbon reservoirs, and natural seismicity at convergent and transform plate boundaries. Each example represents a milestone with regard to bridging the gap between laboratory-scale experiments under controlled boundary conditions and large-scale field studies. The common motivation for all studies is to refine the understanding of how earthquakes nucleate, how they proceed and how they interact in space and time. This is of special relevance at the larger end of the magnitude scale, i.e., for large devastating earthquakes due to their severe socio-economic impact.
Marco Bohnhoff, Georg Dresen, William L. Ellsworth, Hisao Ito
Non-volcanic Tremor: A Window into the Roots of Fault Zones
Abstract
The recent discovery of non-volcanic tremor in Japan and the coincidence of tremor with slow-slip in Cascadia have made earth scientists reevaluate our models for the physical processes in subduction zones and on faults in general. Subduction zones have been studied very closely since the discovery of slow-slip and tremor. This has led to the discovery of a number of related phenomena including low frequency earthquakes and very low frequency earthquakes. All of these events fall into what some have called a new class of events that are governed under a different frictional regime than simple brittle failure. While this model is appealing to many, consensus as to exactly what process generates tremor has yet to be reached. Tremor and related events also provide a window into the deep roots of subduction zones, a poorly understood region that is largely devoid of seismicity. Given that such fundamental questions remain about non-volcanic tremor, slow-slip, and the region in which they occur, we expect that this will be a fruitful field for a long time to come.
Justin L. Rubinstein, David R. Shelly, William L. Ellsworth
Volcanism in Reverse and Strike-Slip Fault Settings
Abstract
Traditionally volcanism is thought to require an extensional state of stress in the crust. This review examines recent relevant data demonstrating that volcanism occurs also in compressional tectonic settings associated with reverse and strike-slip faulting. Data describing the tectonic settings, structural analysis, analogue modelling, petrology, and geochemistry, are integrated to provide a comprehensive presentation of this topic. An increasing amount of field data describes stratovolcanoes in areas of coeval reverse faulting, and shield volcanoes, stratovolcanoes, and monogenic edifices along strike-slip faults, whereas calderas are mostly associated with pull-apart structures in transcurrent regimes. Physically-scaled analogue experiments simulate the propagation of magma in these settings, and taken together with data from subvolcanic magma bodies, they provide insight into the magma paths followed from the crust to the surface. In several transcurrent tectonic plate boundary regions, volcanoes are aligned along both the strike-slip faults and along fractures normal to the local least principal stress (σ3). At subduction zones, intra-arc tectonics is frequently characterised by contraction or transpression. In intra-plate tectonic settings, volcanism can develop in conjunction with reverse faults or strike slip faults. In most of these cases, magma appears to reach the surface along fractures striking parallel to the local σ1. In some cases, there is a direct geometric control by the substrate strike-slip or reverse fault: magma is transported beneath the volcano to the surface along the main faults, irrespective of the orientation of σ3. The petrology and geochemistry of lavas erupted in compressive stress regimes indicate longer crustal residence times, and higher degrees of lower crustal and upper crustal melts contributing to the evolving magmas when compared to lavas from extensional stress regimes. Small volumes of magma tend to rise to shallow crustal levels, and magma mixing is common in the compressional regimes. In detailed studies from the Andes and Anatolia, with geographic and temporal coverage with which to compare compressional, transcurrent and extensional episodes in the same location, there do not appear to be changes to the mantle or crustal source materials that constitute the magmas. Rather, as the stress regime becomes more compressional, the magma transport pathways become more diffuse, and the crustal residence time and crustal interaction increases.
Alessandro Tibaldi, Federico Pasquarè, Daniel Tormey
DynaQlim – Upper Mantle Dynamics and Quaternary Climate in Cratonic Areas
Abstract
The isostatic adjustment of the solid Earth to the glacial loading (GIA, Glacial Isostatic Adjustment) with its temporal signature offers a great opportunity to retrieve information of Earth’s upper mantle to the changing mass of glaciers and ice sheets, which in turn is driven by variations in Quaternary climate. DynaQlim (Upper Mantle Dynamics and Quaternary Climate in Cratonic Areas) has its focus to study the relations between upper mantle dynamics, its composition and physical properties, temperature, rheology, and Quaternary climate. Its regional focus lies on the cratonic areas of northern Canada and Scandinavia.
Geodetic methods like repeated precise levelling, tide gauges, high-resolution observations of recent movements, gravity change and monitoring of postglacial faults have given information on the GIA process for more than 100 years. They are accompanied by more recent techniques like GPS observations and the GRACE and GOCE satellite missions which provide additional global and regional constraints on the gravity field. Combining geodetic observations with seismological investigations, studies of the postglacial faults and continuum mechanical modelling of GIA, DynaQlim offers new insights into properties of the lithosphere. Another step toward a better understanding of GIA has been the joint inversion of different types of observational data – preferentially connected with geological relative sea-level evidence of the Earth’s rebound during the last 10,000 years.
Due to the changes in the lithospheric stress state large faults ruptured violently at the end of the last glaciation in large earthquakes, up to the magnitudes MW = 7–8. Whether the rebound stress is still able to trigger a significant fraction of intraplate seismic events in these regions is not completely understood due to the complexity and spatial heterogeneity of the regional stress field. Understanding of this mechanism is of societal importance.
Glacial ice sheet dynamics are constrained by the coupled process of the deformation of the viscoelastic solid Earth, the ocean and climate variability. Exactly how the climate and oceans reorganize to sustain growth of ice sheets that ground to continents and shallow continental shelves is poorly understood. Incorporation of nonlinear feedback in modelling both ocean heat transport systems and atmospheric CO2 is a major challenge. Climate-related loading cycles and episodes are expected to be important, hence also more short-term features of palaeoclimate should be explicitly treated.
Markku Poutanen, Doris Dransch, Søren Gregersen, Sören Haubrock, Erik R. Ivins, Volker Klemann, Elena Kozlovskaya, Ilmo Kukkonen, Björn Lund, Juha-Pekka Lunkka, Glenn Milne, Jürgen Müller, Christophe Pascal, Bjørn R. Pettersen, Hans-Georg Scherneck, Holger Steffen, Bert Vermeersen, Detlef Wolf
Ultradeep Rocks and Diamonds in the Light of Advanced Scientific Technologies
Abstract
This is a review paper which summarizes recent achievements in studies of superdeep mantle rocks and diamonds from kimberlite and ultrahigh-pressure metamorphic (UHPM) terranes using advanced analytical techniques and instrumentations such as focused ion beam (FIB)-assisted transmission electron microscopy (TEM) and synchrotron-assisted infrared spectroscopy. In combination, they allow characterization of geological materials formed at varying pressures, temperatures, and stresses in different chemical environments, which has enabled us to make amazing advances in understanding large-scale processes operating in the Earth through plate tectonics. Mineralogical characterisations of the ultradeep earth materials using novel techniques with high spatial and energy resolution are resulting in unexpected discoveries of new phases, thereby providing better constraints on deep mantle processes. One of such results is that the nanometric fluid inclusions in diamonds from kimberlite and UHPM terranes contain similar elements such as Cl, K, P, and S. Such similarity reflects probably the high solubility of these elements in a diamond-forming C–O–H supercritical fluid at high pressures and temperatures. The paper emphasizes the necessity of further studies of diamonds occurred within geological setting (oceanic islands, foearcs and mantle sections of ophiolites) previously unrecognized as suitable places for high pressure minerals formation.
Larissa F. Dobrzhinetskaya, Richard Wirth
New Views of the Earth’s Inner Core from Computational Mineral Physics
Abstract
Although one third of the mass of our planet resides in its metallic core (divided into a molten outer part and a solid inner part), fundamental properties such as its chemical composition and internal structure remain poorly known. Although it is well established that the inner core consists of iron with some alloying lighter element(s), the crystal structure of the iron and the nature and concentrations of the light element(s) involved remain controversial. Seismologists, by studying the propagation characteristics of primary earthquake waves (P-waves), have shown that the inner core is anisotropic and layered, but the origins of these properties are not understood. Seismically observed shear waves (S-waves) add to the complexity as they show unexpectedly low propagation velocities through the inner core.
Interpretation of these seismic observations is hampered by our lack of knowledge of the physical properties of core phases at core conditions. In addition, the accuracy of derived inner core seismic properties is limited by the need to de-convolve inner core observations from seismic structure elsewhere in the Earth. This is particularly relevant in the case of shear waves where detection is far from straightforward. A combination of well-constrained seismological data and accurate high-pressure, high-temperature elastic properties of candidate core materials would allow for a full determination of the structure and composition of the inner core - an essential prerequisite to understanding Earth’s differentiation and evolution.
Unfortunately, the extreme conditions of pressure (up to 360 GPa or 3.6 million times atmospheric pressure) and temperature (up to 6000 K) required make results from laboratory experiments unavoidably inconclusive at present. An alternative and complementary approach, that has only recently become available, is computational mineral physics, which uses computer simulations of materials at inner core conditions. Ab initio molecular dynamics simulations have been used to determine the stable phase(s) of iron in the Earth’s core and to calculate the elasticity of iron and iron alloys at core conditions. Calculated S-wave velocities are significantly higher than those inferred from seismology. If the seismological observations are robust, a possible explanation for this discrepancy is that the inner core contains a significant amount of melt (possibly >10%). The observed anisotropy can only be explained by almost total alignment of inner core crystals.
Lidunka Vočadlo
Backmatter
Metadata
Title
New Frontiers in Integrated Solid Earth Sciences
Editors
S. Cloetingh
Jorg Negendank
Copyright Year
2010
Publisher
Springer Netherlands
Electronic ISBN
978-90-481-2737-5
Print ISBN
978-90-481-2736-8
DOI
https://doi.org/10.1007/978-90-481-2737-5