Geophysical measurements can reveal the structure of icy ocean worlds and cycling volatiles. The associated density, temperature, sound speed, electrical conductivity such thus characterizes their habitability. To explore variability correlation these parameters, to provide tools for planning data analyses, we develop 1-D calculations internal structure, which use available constraints on thermodynamics aqueous MgSO$_4$, NaCl (as seawater), NH$_3$, water ices, silicate content. Limits in...

Abstract Geological and geodynamic models of the mantle often rely on joint interpretations published seismic tomography images petrological/geochemical data. This approach tends to neglect fundamental limitations of, uncertainties in, results. These involve theory, correcting for crust, lack rays throughout much mantle, difficulty in obtaining true strength anomalies, choice what background model subtract reveal cross‐sections select publication. The aim this review is provide a relatively...

Imposing a thermal and compositional significance to the outcome of inversion seismic data facilitates their interpretation. Using long-period waveforms an approach that includes constraints from mineral physics, we find lateral variations temperature can explain large part in upper mantle. The additional signature cratons emerges global model as well. Above 300 km, obtain geotherms span range expected temperatures various tectonic regions. Absolute velocities gradients with depth are well...

Mapping the thermal and compositional structure of upper mantle requires a combined interpretation geophysical petrological observations. Based on current knowledge material properties, we interpret available global seismic models for temperature assuming end-member structures. In particular, test effects modelling depleted lithosphere, which accounts constraints continents. Differences between translate into large density variations, respectively, up to 400 K 0.06 g cm-3 at 150 km depth....

Abstract We present a new global model of shear and compressional wave speeds for the entire mantle, partly based on data set employed velocity savani . invert Rayleigh Love surface waves up to sixth overtone in combination with major P S body phases. Mineral physics isotropic δ ln V / ratio are taken into account form regularization constraint. The relationship between that we observe top 300 km mantle has important thermochemical implications. Back‐arc basins Western Pacific characterized...

A 1-D reference model for the mantle that is physically meaningful would be invaluable both in geodynamic modelling and an accurate interpretation of 3-D seismic tomography. However, previous studies have shown it difficult to reconcile simplest possible physical model—1300°C adiabatic pyrolite—with observations. We therefore generate a set alternative thermal chemical models, down 900 km depth, compare their properties with data. use several different body surface wave data sets provide...

Equation‐of‐state (EOS) modeling, whereby the seismic properties of a specified thermochemical structure are constructed from mineral physics constraints, and compared with global data, provides potentially powerful tool for distinguishing between plausible mantle structures. However, previous such studies at lower depths have been hampered by insufficient evaluation uncertainties, overestimation or biases in type and/or data used. This has led to wide, often conflicting, variety models...

Unravelling the thermal structure of outermost shell our planet is key for understanding its evolution. We obtain temperatures from interpretation global shear-velocity (VS) models. Long-wavelength well determined by seismic models and only slightly affected compositional effects uncertainties in mineral-physics properties. Absolute gradients with depth, however, are not constrained. Adding constraints petrology, heat-flow observations evolution oceanic lithosphere helps to better estimate...

One‐dimensional seismic reference models are known to be a nonunique solution global data, hampering an interpretation in terms of physical structure. Here we test the compatibility simplest hypothesis mantle convecting as whole, with constant pyrolitic composition phase transitions, directly against kind data that went into models, focusing on upper structure down 800 km depth. By randomly varying elastic and anelastic parameters main minerals within their uncertainty bounds, generate set...

We test a mineral physics model of the upper mantle against seismic observations. The is based on current knowledge material properties at high temperatures and pressures. In particular, elastic are computed with recent self-consistent thermodynamic model, six oxides (NCFMAS) system. focus average structure between 250 800 km. invert normal modes eigenfrequencies traveltimes to obtain best-fitting thermal structures for various compositional profiles. thermochemical then used predict...

Abstract We explore the influence of major elements chemistry and H 2 O‐content on density seismic velocity crustal rocks by computing stable metastable mineralogy elastic properties as a function pressure temperature (P‐T). Proposed average compositions continental crust result in significantly different properties, for example difference computed ∼ 4 % is obtained at given P‐T. Phase transformations affect point that discontinuities can be explained with mineral reactions rather than...

Abstract. Subduction-related geodynamic processes significantly influence plate tectonics and Earth's evolution, yet their impact on the continental crust remains poorly understood. We investigated Sardinia–Corsica block, situated in Mediterranean Sea, which has experienced intense subduction-driven events. By analyzing P-wave receiver functions from our LiSard (Lithosphere of Sardinia) seismic network publicly available stations, we aimed to understand crustal structure composition....

The crust, despite being the Earth's outermost layer, remains extremely challenging to study given its heterogeneity and complexities. High-resolution integrated tomographic studies at various scales are essential indirectly obtain robust information on compositional physical properties of crust. Greater Alpine Crust (GAC), shaped by Hercynian, Alpine, Apennine orogenies, provides a natural laboratory for studying geodynamic processes plate boundaries. These orogenies have driven continuous...

The thermal structure of the continental lithosphere and its evolution over geological time are critical to understanding processes that govern formation, dynamics, long-term stability. Global shear-wave models, combined with heat-flow data, provide valuable first-order constraints on large-scale temperature distribution thickness (Cammarano Guerri, 2017). However, seismic data alone offer limited resolution for absolute estimates.In contrast, xenolith xenocryst analyses yield localized...

Most of the lower mantle is relatively simple in terms seismic structure. Lateral variations are weaker compared to its bottom part and upper velocities increase smoothly with depth. To a first order, these features appear consistent adiabatic compression homogeneous medium. Here we show, instead, that data require change chemical and/or thermal state depth below ∼1600 km, if effect spin‐transition Fe 2+ ferropericlase on elastic signature typical assemblage taken into account. The inferred...

Multi-method surveys have been used with the aim of detecting either sharp discontinuities (boundary cavity, fractures in medium, etc.) or volumetric variations (bodies different physical properties), at three archaeological test sites. For survey a combination passive and active methods (magnetic, GPR dipole–dipole geoelectric method) has used. With all high-resolution data acquisition method adopted reconstructing global vision area investigated. The enhancement processing technique...

Previous studies have documented the potential for using relatively short‐period body waves and intermediate‐period surface to explore structure tectonics of Europa. We show that long‐period measurements (0.001 0.1 Hz) may large amplitudes displacement (millimeters centimeters) are potentially measurable from orbit without requiring a lander. To accurately model response Europa, we use normal modes calculated physically self‐consistent models Europa's developed in part 1 (Cammarano et al.,...

Abstract Unraveling the temperature distribution and composition of Earth's crust is key for understanding its origin, evolution, mechanical behavior. Models compressional ( V P ) shear wave S velocity are obtained from seismological studies can be interpreted in terms composition, using relationship defined through laboratory experiments. These empirical evidences often do not properly account effects driven by temperature, pressure, water content, phase change minerals. In this study, we...

Abstract We evaluate the thermo‐chemical state of lower mantle by analysing differences in pattern heterogeneity between shear and compressional velocity variations ratio ( ) as mapped our model SPani alternative joint models. Robust structural V P S evidence presence compositional within two Large Low Shear Velocity Provinces (LLSVPs). find also an increasing decorrelation with depth that can be associated layering LLSVPs. In addition, shows transition zone mid complex morphology subducting...

In order to examine the potential of seismology determine interior structure and properties Europa, it is essential calculate seismic velocities attenuation for range plausible interiors. We a models physical as constrained by satellite's composition, mass, moment inertia. assume water‐ice shell, pyrolitic or chondritic mantle, core composed pure iron plus 20 weight percent sulfur. consider two extreme mantle thermal states: hot cold. Given temperature we density, velocities, using...

Thermally activated, viscoelastic relaxation of the Earth's materials is responsible for intrinsic attenuation seismic waves. Seismic observations have been used to define layered radially symmetric models, independent any constraints on temperature and composition. Here, we interpret free-oscillation surface wave measurements in terms physical structures, by using available knowledge mechanisms that govern at upper-mantle (<400 km) conditions. We find can be explained relatively simple...