Physics of the Earth and Planetary Interiors最新文献

{"title":"Unraveling composite magnetic fabrics through tensor decomposition","authors":"David Finn ,&nbsp;Josef Jezek ,&nbsp;Stuart A. Gilder ,&nbsp;Michael R. Wack ,&nbsp;Felix Ostermeier ,&nbsp;Michael Jackson ,&nbsp;Robert S. Coe ,&nbsp;Michael J. Branney","doi":"10.1016/j.pepi.2025.107346","DOIUrl":"10.1016/j.pepi.2025.107346","url":null,"abstract":"<div><div>Magnetic anisotropy plays a central role in many petrofabric and paleomagnetic studies. Anisotropy is typically represented by a second-order symmetric tensor that reflects the combined contributions from mineral populations with differing grain sizes, orientation distributions and particle scale anisotropies. Thus, the quality of geologically significant information obtained from magnetic anisotropy data depends on our ability to disentangle the complexity of these coexisting fabrics. In this study, we present a least-squares technique that can be employed in combination with additional geological or other supporting evidence to separate measured anisotropy tensors into independent contributions with distinct physical meaning. The analysis is readily adaptable and widely applicable to interpreting composite hybrid magnetic anisotropies, like those which arise from tectonic forces.</div><div>Here, we revisit published deposition experiments and anisotropy of anhysteretic remanence (AARM) measurements to demonstrate the usefulness of the tensor decomposition approach. Remanence anisotropy measurements are decomposed into idealized tensorial sub-components originating from the preferred alignment of particles parallel to the magnetic field (field-aligned fabric) and within the bedding plane (sedimentary fabric). The least-squares decomposition isolates the field-aligned fabric by subtracting the sedimentary-compaction fabric. After subtraction of the sedimentary fabric, quantitative paleofield strength and direction can be directly inferred from the field-aligned subfabric.</div></div>","PeriodicalId":54614,"journal":{"name":"Physics of the Earth and Planetary Interiors","volume":"362 ","pages":"Article 107346"},"PeriodicalIF":2.4,"publicationDate":"2025-03-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143715065","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Revising the seismic source of the 1979 Tumaco-Colombia earthquake (Mw = 8.1) for future tsunami hazard assessment","authors":"Bruno Adriano ,&nbsp;Cesar Jimenez ,&nbsp;Erick Mas ,&nbsp;Shunichi Koshimura","doi":"10.1016/j.pepi.2025.107344","DOIUrl":"10.1016/j.pepi.2025.107344","url":null,"abstract":"<div><div>The 1979 Great Tumaco earthquake occurred on 12 December and had a moment magnitude of Mw = 8.1. Its epicenter was located about 10 km offshore the Colombia-Ecuador Pacific border. This earthquake generated a catastrophic tsunami that destroyed several small communities on South America's Pacific coast. Several locations in Central America and in Hawaii also recorded tsunami waves with heights up to 50 cm. Thus, understanding this event's source characteristics and effects is vital for future tsunami hazard assessments in countries in the Pacific Ocean. This study revised the earthquake source using a joint inversion of tsunami waves and geodetic records. Further, this study also analyzed the tsunami propagation characteristics on the Pacific coast of North and South America using the revised earthquake source model.</div><div>The inversion results indicate that the earthquake source presented main slip asperities north of the epicenter, with a maximum slip of 3.40 m. It also presented a second large slip of 2.87 m, located south of the epicenter. The earthquake also generated a ground subsidence of up to 50 cm along the Ecuador-Colombia coastline. The uplifted zone was estimated beneath the sea, with the most significant displacement area north of the epicenter, with a maximum uplift of 1.16 m. The comparison between the observed and simulated tsunami waveforms of the 1979 Tumaco earthquake shows that, in general, there is a good correlation for the first period of the tsunami waveforms. The tsunami simulation results suggest a maximum coastal tsunami height of 3.5 m along the coast of Panama and Costa Rica, about 600 km from the earthquake source area.</div></div>","PeriodicalId":54614,"journal":{"name":"Physics of the Earth and Planetary Interiors","volume":"362 ","pages":"Article 107344"},"PeriodicalIF":2.4,"publicationDate":"2025-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143715066","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Rapid geomagnetic variations and stable stratification at the top of Earth's core","authors":"Julien Aubert","doi":"10.1016/j.pepi.2025.107335","DOIUrl":"10.1016/j.pepi.2025.107335","url":null,"abstract":"<div><div>Probing the possible presence and physical properties of a stably stratified layer atop Earth's core is crucial to better determine the past history and heat budget of the planet. This has previously been done by ascribing a variety of interannual to decadal geomagnetic variations to hydromagnetic waves internal to the layer. This study presents the first self-consistent simulation of the stratified layer dynamics in interplay with the underlying core convection, in physical conditions matching those of Earth's core. Magneto-Archimedes-Coriolis waves of decadal periods appear in stratified layers deeper than a few tens of kilometers and with Brunt-Väisälä frequency matching the rotation rate of the planet. However, the level at which core convection excites these waves is generally insufficient to account for observed geomagnetic variations in this period range. Strong stratification is furthermore deleterious to a number of observed features that unstratified models are successful at reproducing. Fluid flow at the core surface decouples from the interior and becomes strongly dissimilar to geomagnetic inferences. Magnetic jerks and their corresponding near-equatorial, rapidly alternating magnetic acceleration patterns also disappear, because the supporting interannual magneto-Coriolis waves are impeded by the stratified layer. This negative impact on the reproduction of the observed rapid geomagnetic variations limits the possible extent of a stable top layer to the first few tens of kilometers beneath Earth's core surface.</div></div>","PeriodicalId":54614,"journal":{"name":"Physics of the Earth and Planetary Interiors","volume":"362 ","pages":"Article 107335"},"PeriodicalIF":2.4,"publicationDate":"2025-03-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143642229","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Archaeointensity study of pottery from the Maya settlements of La Blanca and Chilonché (Petén, Guatemala): New data to constrain the geomagnetic field evolution in Central America","authors":"M. Gómez-Paccard ,&nbsp;A. Chauvin ,&nbsp;R. Bonilla-Alba ,&nbsp;C. Vidal-Lorenzo ,&nbsp;M. Salas","doi":"10.1016/j.pepi.2025.107343","DOIUrl":"10.1016/j.pepi.2025.107343","url":null,"abstract":"<div><div>Accurate determination of the spatio-temporal variation of the geomagnetic field before direct measurements relies on reliable archaeomagnetic data. This study presents new archaeointensity data from Central America, a region with paucity of archaeomagnetic data. We specifically investigate 71 Maya pottery fragments collected at the “La Blanca” and “Chilonché” archaeological sites in Guatemala, with ages ranging between 600 and 1100 CE. We employed the classical Thellier-Thellier palaeointensity method, including partial thermoremanent magnetization (pTRM) checks, TRM anisotropy, and cooling rate corrections at the specimen level. Out of 252 specimens analyzed, only 50 from 14 fragments yielded successful results. The fragment-mean intensities obtained meet modern standards and are considered technically robust. Our findings indicate significant variability even among samples from the same period, likely due to age disparities among fragments, undetected issues in magnetic properties of the analyzed potteries and fluctuations in geomagnetic intensity. To better understand this variability, acquiring new data with higher precision dating, ideally at multi-decadal intervals, is essential. A comparison with selected previous palaeointensities, regional palaeosecular variation curves from Mexico, and global geomagnetic field models' predictions confirms that the current understanding of geomagnetic field strength evolution in Central America is unsatisfactory due to the low number of archaeomagnetic data and their significant dispersion. In this context, new high-quality palaeointensity data are required to serve as a constrain for establishing the geomagnetic field behavior in Central American during the first millennium CE and to contribute improving regional and global geomagnetic field reconstructions.</div></div>","PeriodicalId":54614,"journal":{"name":"Physics of the Earth and Planetary Interiors","volume":"362 ","pages":"Article 107343"},"PeriodicalIF":2.4,"publicationDate":"2025-03-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143629175","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Spectral characteristics and implications of located low-frequency marsquakes and impact events from InSight SEIS observations","authors":"Weijia Sun ,&nbsp;Hrvoje Tkalčić ,&nbsp;Jieying Chen ,&nbsp;Sheng Wang","doi":"10.1016/j.pepi.2025.107334","DOIUrl":"10.1016/j.pepi.2025.107334","url":null,"abstract":"<div><div>The frequency characteristics of recorded ground motion are crucial to understanding seismic wavefield originating in marsquakes and interior structures of Mars, such as seismic velocity and discontinuities. Based on the frequency content, the Marsquake Service (MQS) categorized marsquakes into low-frequency (LF) and high-frequency (HF) families and further classified them into subcategories. For example, the LF family consists of two types: low frequency (LF; &lt; 1 Hz) and broadband (BB; predominantly &lt;2.4 Hz). Previous studies have presented the frequency characteristics of a few significant marsquakes. With the recent application of new techniques, more marsquakes with a quality high enough to be characterized as “QB” have been located. These newly located marsquakes have the potential to constrain the internal structure of Mars, but seven of them occurring during sols 0–1011 and their spectral characteristics have not been discussed yet. Here, we first summarize these seven LF-type, B-quality marsquakes: S0185a, S0325a, S0407a, S0409d, S0484b, S0916d, and S0918a following the standard procedures of Marsquake Service. Additionally, we examine the characteristics of the two largest impact events, S1000a and S1094b, classified as BB events. We determined the frequency bounds in the Butterworth bandpass filter of all A- and B-quality LF-family marsquakes and the two impact events. We found that most LF-family marsquakes have an upper bound frequency no larger than 1 Hz, except for S0235b, reaching 1.1 Hz. Moreover, the P- and S-wave arrivals of marsquakes present highly varied spectral behaviors based on the analysis of the spectral ratio between P and S waves. We finally discuss the implications of the highly varied spectrum and S-to-P spectral ratio for these marsquakes.</div></div>","PeriodicalId":54614,"journal":{"name":"Physics of the Earth and Planetary Interiors","volume":"361 ","pages":"Article 107334"},"PeriodicalIF":2.4,"publicationDate":"2025-02-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143551096","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Three-dimensional magnetotelluric inversion with structurally guided regularization constraint","authors":"Dieno Diba ,&nbsp;Han Song ,&nbsp;Makoto Uyeshima ,&nbsp;Yoshiya Usui","doi":"10.1016/j.pepi.2025.107333","DOIUrl":"10.1016/j.pepi.2025.107333","url":null,"abstract":"<div><div>We propose a novel technique for the structurally regularized three-dimensional magnetotelluric inversion scheme. In the proposed method, the structural resemblance between the inverted electrical resistivity model and the independently derived guiding model is enforced by controlling the weights of the roughness operator for regularization. Using a simple mathematical function, we forced the weights to be small across presumed discontinuities in the guiding model, allowing for sharp changes in resistivity values across the discontinuity. We forced the weights to be large along blocks with similar values in guiding physical parameters, enforcing smooth changes of resistivity along the blocks. Numerical inversion tests indicate that the new guided inversion produces a resistivity model that closely approximates the true model, surpassing the results of both conventional smooth inversion and cross-gradient inversion, particularly when a perfectly correlated guiding model is used. We applied our guided inversion method to magnetotelluric data in Southern Tohoku, Northeast Japan, with structural constraints from a seismic velocity structure. Given the non-uniqueness problem of MT inversion, guided inversion enables the exploration of alternative resistivity structures that are more consistent with geological or geophysical models than those produced by conventional smooth inversion, therefore expanding the possibility of interpretation. We suggest that the proposed inversion method can serve as an alternative to the commonly used cross-gradient method, especially in the absence of objective schemes for the simultaneous selection of multiple trade-off parameters in the objective function.</div></div>","PeriodicalId":54614,"journal":{"name":"Physics of the Earth and Planetary Interiors","volume":"361 ","pages":"Article 107333"},"PeriodicalIF":2.4,"publicationDate":"2025-02-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143550985","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"On the possibility of convection in the Venusian crust","authors":"Viatcheslav S. Solomatov,&nbsp;Chhavi Jain","doi":"10.1016/j.pepi.2025.107332","DOIUrl":"10.1016/j.pepi.2025.107332","url":null,"abstract":"<div><div>We evaluate the possibility of convection in the Venusian crust by utilizing recently developed scaling laws for the onset of convection in temperature- and stress-dependent viscosity fluids, heated from below or from within. We find that crustal convection can occur within plausible ranges of surface heat flux, crustal thickness, and rheologies. Crustal convection can occur at subsolidus temperatures if the grain size is less than 0.1 mm and the crust is relatively thick, close to the gabbro-eclogite transition. For larger grain sizes, particularly where deformation occurs through dislocation creep, crustal convection is likely to occur only at supersolidus temperatures. If crustal convection does occur in the Venusian crust, it would increase heat transport efficiency in the crust and affect the interior dynamics and evolution of the planet. It would also generate thermal variations within the crust that would affect the constraints on the elastic thickness and the heat flux from gravity and topography data analysis. Further investigation of the two-phase dynamics of a partially molten crust is essential for a better understanding of crustal convection and accurate interpretation of surface observations.</div></div>","PeriodicalId":54614,"journal":{"name":"Physics of the Earth and Planetary Interiors","volume":"361 ","pages":"Article 107332"},"PeriodicalIF":2.4,"publicationDate":"2025-02-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143510628","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of chemistry on the compressibility and high-pressure structural evolution of the CaFe2O4-type aluminous silicate phase","authors":"Giacomo Criniti ,&nbsp;Tiziana Boffa Ballaran ,&nbsp;Alexander Kurnosov ,&nbsp;Takayuki Ishii ,&nbsp;Elena-Marie Rogmann ,&nbsp;Konstantin Glazyrin ,&nbsp;Timofey Fedotenko ,&nbsp;Daniel J. Frost","doi":"10.1016/j.pepi.2025.107331","DOIUrl":"10.1016/j.pepi.2025.107331","url":null,"abstract":"<div><div>Approximately 22–26 vol% of a basaltic phase assemblage at lower mantle conditions is comprised of a (Na,Mg,Fe²⁺)(Al,Si,Fe³⁺)₂O₄ phase with CaFe₂O₄-type (CF-type) structure. Previous experimental studies attempted to determine the equation of state of the CF-type phase but reported contrasting compressibility values, even for samples with the same composition. Therefore, the elastic properties of the CF-type phase remain, to date, largely unconstrained. Here, we conducted single-crystal X-ray diffraction (SCXRD) measurements in the diamond anvil cell (DAC) at high pressure and room temperature on three samples of CF-type phase with compositions Na_0.90(1)Al_1.03(2)Si_1.00(2)O₄ (NaCF), Na_0.66(4)Mg_0.28(4)Al_1.22(3)Si_0.78(3)O₄ (MgCF) and Na_0.62(2)Mg_0.19(1)Fe²⁺_0.17(1)Fe³⁺_0.080(4)Al_1.20(3)Si_0.70(1)O₄ (FeCF). A multi-sample loading approach was employed for most DAC runs, where two samples were loaded in the same sample chamber to reduce possible systematic deviations between datasets, thus enhancing internal consistency and corroborating data reproducibility. Experiments on the NaCF and MgCF samples were conducted up to ∼50 GPa, while the FeCF sample was compressed to ∼72 GPa to better characterize the effect of the spin crossover of octahedrally coordinated Fe³⁺. We found the isothermal bulk modulus (<em>K</em>_T0) to increase with decreasing NaAlSiO₄ content, accompanied by only a slight decrease in its pressure derivative (<em>K'</em>_T0). Analysis of the crystal structures of the three samples at high pressure allowed compositional trends to be determined also for the interatomic bonds and polyhedral compressibility, as well as the distortion indices. These suggest an overall stiffening of the A site with increasing Mg²⁺ and Fe²⁺ content, as well of the two B sites with increasing Al³⁺ and Fe³⁺ content. Enhanced compressibility of the unit cell and octahedral B sites was observed between ∼26–42 GPa in the FeCF sample, suggesting a pressure-induced spin crossover of Fe³⁺, in agreement with some previous observations. Finally, trends in the elastic properties from experimental studies conducted along the NaAlSiO₄-MgAl₂O₄ join are discussed and used as a proxy to evaluate the reliability of end-member properties for the CF-type phase employed in most recent mineral physical and thermodynamic databases. Our analysis suggests current mineral physical models might underestimate densities and overestimate bulk sound velocities of NaAlSiO₄-rich CF-type phases with basaltic composition.</div></div>","PeriodicalId":54614,"journal":{"name":"Physics of the Earth and Planetary Interiors","volume":"361 ","pages":"Article 107331"},"PeriodicalIF":2.4,"publicationDate":"2025-02-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143512264","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A 6-year quasi-periodicity in the geomagnetic secular acceleration pulses over 1932–2022","authors":"R. Sidorov ,&nbsp;A. Soloviev ,&nbsp;Sh. Bogoutdinov","doi":"10.1016/j.pepi.2025.107330","DOIUrl":"10.1016/j.pepi.2025.107330","url":null,"abstract":"<div><div>Recent studies suggest that the secular variation dynamics of the geomagnetic field exhibits periodic patterns that indicate underlying wave processes in the Earth's core. However, analytical models of the core geomagnetic field based on geographically sparse and noisy observatory data have apparent limitations for studying fine structure of its spatiotemporal variations. The advent of satellite measurements of the full geomagnetic field vector in 1999 removed this limitation and made it possible to produce reliable and highly accurate models of the secular variation that allow downward continuation to the core-mantle boundary. These models have revealed rapid core field variations on a time scale of the order of 10 years. In particular, the 6-year quasi-periodicity in the second time derivative of the geomagnetic field has been discovered. In this research, we build on our previous works to extract the secular variation and secular acceleration signal from the magnetic observatory datasets over a longer period. As a result, our approach to data analysis has made it possible to confirm the existence of a 3-year quasi-periodicity of secular acceleration pulses of alternating polarity over 90-year period (1932–2022), i.e. far before the advent of the space era. The proposed methodology does not imply an intermediate production of a core field model, as done according to classical approaches.</div></div>","PeriodicalId":54614,"journal":{"name":"Physics of the Earth and Planetary Interiors","volume":"361 ","pages":"Article 107330"},"PeriodicalIF":2.4,"publicationDate":"2025-02-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143465133","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"SeisTeC: A neural network tool to constrain mantle thermal and chemical properties from seismic observables","authors":"Ashim Rijal,&nbsp;Laura Cobden,&nbsp;Jeannot Trampert","doi":"10.1016/j.pepi.2025.107317","DOIUrl":"10.1016/j.pepi.2025.107317","url":null,"abstract":"&lt;div&gt;&lt;div&gt;Three-dimensional variations of wave speeds and density have identified the presence of seismically distinct structures in the Earth's mantle. To determine the thermochemical properties and dynamic relevance of these structures, it is crucial to understand the relationship between seismic properties and temperature and composition. However, multiple thermochemical parameters influence seismic wave speeds simultaneously. A given wave speed pair (compressional and shear) and density can be generated by many possible combinations of thermochemical parameters, which makes the inversion of wave speeds and density for thermochemical parameters a non-unique problem. We have developed a tool which efficiently captures the mapping between seismic wave speeds (and density) and thermochemical properties, with the capacity to represent both the inherent trade-offs between parameters as well as data uncertainties. These trade-offs and uncertainties are represented by the posterior probability density function provided by a neural network. We demonstrate the concept for seismic wave speeds and density, but the same tool can also be adapted for other parameters such as attenuation or properties of seismic discontinuities. SeisTeC is available to the wider community and is intended to facilitate interpretations of seismic structures inside the Earth, or in general, any planetary bodies.&lt;/div&gt;&lt;div&gt;Our tool is based on a neural network, which implicitly learns the non-linear mapping between temperature and bulk composition. We chose the example of the lower mantle and expressed composition in terms of six end-member oxides (&lt;span&gt;&lt;math&gt;&lt;msub&gt;&lt;mi&gt;SiO&lt;/mi&gt;&lt;mn&gt;2&lt;/mn&gt;&lt;/msub&gt;&lt;mo&gt;,&lt;/mo&gt;&lt;mi&gt;MgO&lt;/mi&gt;&lt;mo&gt;,&lt;/mo&gt;&lt;msub&gt;&lt;mi&gt;Al&lt;/mi&gt;&lt;mn&gt;2&lt;/mn&gt;&lt;/msub&gt;&lt;msub&gt;&lt;mi&gt;O&lt;/mi&gt;&lt;mn&gt;3&lt;/mn&gt;&lt;/msub&gt;&lt;mo&gt;,&lt;/mo&gt;&lt;mi&gt;FeO&lt;/mi&gt;&lt;mo&gt;,&lt;/mo&gt;&lt;msub&gt;&lt;mi&gt;Na&lt;/mi&gt;&lt;mn&gt;2&lt;/mn&gt;&lt;/msub&gt;&lt;mi&gt;O&lt;/mi&gt;&lt;mo&gt;,&lt;/mo&gt;&lt;mi&gt;CaO&lt;/mi&gt;&lt;/math&gt;&lt;/span&gt;) and modelled seismic wave speeds and density at appropriate temperature and pressure conditions. Wave speeds and density are calculated for 750,000 thermochemical models, whose temperature and composition are selected at random from pre-defined ranges, using thermodynamic modelling. We train neural networks with wave speeds plus or minus density as the input, and temperature and bulk composition as target outputs. The networks then approximate a probability density function for each output, which allows us to interpret seismic observables in terms of physical parameters, crucially, with uncertainties. When working with wave speeds (&lt;span&gt;&lt;math&gt;&lt;msub&gt;&lt;mi&gt;V&lt;/mi&gt;&lt;mi&gt;P&lt;/mi&gt;&lt;/msub&gt;&lt;/math&gt;&lt;/span&gt; and &lt;span&gt;&lt;math&gt;&lt;msub&gt;&lt;mi&gt;V&lt;/mi&gt;&lt;mi&gt;S&lt;/mi&gt;&lt;/msub&gt;&lt;/math&gt;&lt;/span&gt;) only, we find trade-offs between pairs of parameters such as temperature - &lt;span&gt;&lt;math&gt;&lt;mi&gt;FeO&lt;/mi&gt;&lt;/math&gt;&lt;/span&gt;, &lt;span&gt;&lt;math&gt;&lt;msub&gt;&lt;mi&gt;SiO&lt;/mi&gt;&lt;mn&gt;2&lt;/mn&gt;&lt;/msub&gt;&lt;/math&gt;&lt;/span&gt; - &lt;span&gt;&lt;math&gt;&lt;mi&gt;MgO&lt;/mi&gt;&lt;/math&gt;&lt;/span&gt;, &lt;span&gt;&lt;math&gt;&lt;msub&gt;&lt;mi&gt;SiO&lt;/mi&gt;&lt;mn&gt;2&lt;/mn&gt;&lt;/msub&gt;&lt;/math&gt;&lt;/span&gt; - &lt;span&gt;&lt;math&gt;&lt;msub&gt;&lt;mi&gt;Na&lt;/mi&gt;&lt;mn&gt;2&lt;/mn&gt;&lt;/msub&gt;&lt;m","PeriodicalId":54614,"journal":{"name":"Physics of the Earth and Planetary Interiors","volume":"361 ","pages":"Article 107317"},"PeriodicalIF":2.4,"publicationDate":"2025-02-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143465132","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}