Physics of the Earth and Planetary Interiors最新文献

{"title":"Subsurface structural trends in Central-Western India: Inferences from magnetotelluric data using the complex MT apparent resistivity tensor","authors":"Abdul Azeez K.K.","doi":"10.1016/j.pepi.2024.107248","DOIUrl":"10.1016/j.pepi.2024.107248","url":null,"abstract":"<div><p>The central-western part of the Indian subcontinent exhibits significant geological diversity and possesses a rich record of different tectonothermal events in the earth's evolutionary history, spanning from the Archean to the present. Precambrian geology in the region is mostly obscured by Cretaceous-Tertiary/Paleocene volcanic eruptions and Proterozoic to Quaternary/recent sedimentary cover. Magnetotelluric (MT) impedance and tipper responses from 146 stations, covering central-western India in a grid fashion with a spacing of ∼55 km, were analyzed to evaluate the subsurface structural trends, dimensionalities, and qualitative characteristics of the electric lithosphere in the region. An advanced Complex Apparent Resistivity Tensor (CART) approach, along with the popular Phase Tensor (PT) approach and induction arrows are utilized to achieve the above goals. The analysis revealed a high degree of 3D induction effects in the data at almost every station and period. The directionality information retrieved from the tensor properties showed that the structural trends in the deep crust and upper mantle of the major geologic domains correlate with the known surface tectonic trend of the respective geologic domain. This study provides vital evidence to support the suspected bifurcation of the Precambrian Aravalli-Delhi Mobile Belt (ADMB) tectonic trend and its extensions into neighboring Kutch, Saurashtra, and Central Indian Tectonic Zone (CITZ) domains. The analysis results indicate a lithospheric scale enhanced conductivity beneath the Malwa plateau, which marks the first major phase of the Reunion mantle plume eruption in India. A critical finding of this study is that the Resistivity Phase Tensor better defines the subsurface resistivity structure and provides much clearer structural information than the conventional Phase Tensor.</p></div>","PeriodicalId":54614,"journal":{"name":"Physics of the Earth and Planetary Interiors","volume":"355 ","pages":"Article 107248"},"PeriodicalIF":2.4,"publicationDate":"2024-08-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142021351","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":"Microseismicity detection and spatial-temporal migration in the Xinfengjiang reservoir, Guangdong, China","authors":"Peng Zhang ,&nbsp;Xinlei Sun ,&nbsp;Jianye Zong ,&nbsp;Zhuo Xiao ,&nbsp;Yusong Shen","doi":"10.1016/j.pepi.2024.107245","DOIUrl":"10.1016/j.pepi.2024.107245","url":null,"abstract":"<div><p>There have been many earthquakes in the Xinfengjiang Reservoir (XFJR) in the past 60 years since the M6.1 earthquake that occurred in 1961. In the XFJR, seismicity has migrated from southeast to northwest; however, the mechanisms for this migration have not yet been fully investigated. In this study, we used six years of data from both permanent and temporary seismic networks in the XFJR to detect &gt;23,500 earthquake events using the EQTransformer. The minimum magnitude of completeness of the earthquake catalog decreased to −0.1, and the spatial distribution of the microearthquakes showed clear high-angle faults in the area, which included a new fault within the reservoir. The focal mechanism inversion results showed that earthquakes in the northwestern cluster changed from strike-slip to dip-slip faults with time whereas those in the southeastern cluster remained a mixture of strike-slip and dip-slip faults. Further analysis showed that spatiotemporal variation in the northwestern reservoir was due to earthquake migration along different faults. Overall, we concluded that earthquake in the whole XFJR area were affected by water infiltration along fault zone; Coulomb stress transfer may also contribute to the migration of earthquakes from southeast to northwest direction.</p></div>","PeriodicalId":54614,"journal":{"name":"Physics of the Earth and Planetary Interiors","volume":"355 ","pages":"Article 107245"},"PeriodicalIF":2.4,"publicationDate":"2024-08-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142050259","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":"The link between gas extraction and shallow seismicity around the Dalan gas field of Zagros Mountains, Iran","authors":"Mir Ali Hassanzadeh ,&nbsp;Mohammadreza Jamalreyhani ,&nbsp;Shiva Arvin ,&nbsp;Shaghayegh VahidRavesh","doi":"10.1016/j.pepi.2024.107246","DOIUrl":"10.1016/j.pepi.2024.107246","url":null,"abstract":"<div><p>We analyze seismicity from 2013 to 2023 near Bushkan village in the Fars arc of the Zagros folded belt, colocated with the Dalan natural gas field. A previous study suggested unusual seismic behavior in the 2014–15 cluster, linking larger events to shallow depths (∼5 km) on steep reverse faults within the Dalan anticline. Nevertheless, ongoing debates persist regarding the potential correlation of seismicity with activities in the Dalan field. Our study investigates seismic activities using relocation, moment tensor inversion, stress inversion, and remote sensing techniques. We relocated 35 events above magnitude 3 and reconstructed source parameters for 12 events (M 4+) with uncertainties. Focal mechanisms were inverted, and morphology remote sensing was employed to ascertain the active stress state. Besides the 2014–15 cluster, we found a separate strike-slip cluster in 2018 at shallower depths (3–4 km), unusual for Zagros earthquakes. We suggest that pore pressure variations influence seismic sequences in the Dalan gas field area. However, distinguishing between human-induced and natural earthquakes in regions like Zagros with naturally elevated seismicity is challenging.</p></div>","PeriodicalId":54614,"journal":{"name":"Physics of the Earth and Planetary Interiors","volume":"355 ","pages":"Article 107246"},"PeriodicalIF":2.4,"publicationDate":"2024-08-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141993282","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":"Reevaluating the fate of subducted magnesite in the Earth's lower mantle","authors":"Lélia Libon ,&nbsp;Georg Spiekermann ,&nbsp;Ingrid Blanchard ,&nbsp;Johannes M. Kaa ,&nbsp;Serena Dominijanni ,&nbsp;Melanie J. Sieber ,&nbsp;Mirko Förster ,&nbsp;Christian Albers ,&nbsp;Wolfgang Morgenroth ,&nbsp;Catherine McCammon ,&nbsp;Anja Schreiber ,&nbsp;Vladimir Roddatis ,&nbsp;Konstantin Glazyrin ,&nbsp;Rachel J. Husband ,&nbsp;Louis Hennet ,&nbsp;Karen Appel ,&nbsp;Max Wilke","doi":"10.1016/j.pepi.2024.107238","DOIUrl":"10.1016/j.pepi.2024.107238","url":null,"abstract":"<div><p>The role that subducted carbonates play in sourcing and storing carbon in the deep Earth's interior is uncertain, primarily due to poor constraints on the stability of carbonate minerals when interacting with mantle phases. Magnesite (<span><math><msub><mtext>MgCO</mtext><mn>3</mn></msub></math></span>) is the most prominent carbonate phase to be present at all mantle pressure-temperature conditions. In this study, we combined multi-anvil apparatus and laser-heated diamond anvil cell experiments to investigate the stability of magnesite in contact with iron-bearing bridgmanite. We examined the presence of melt, decarbonation, and diamond formation at shallow to mid-lower mantle conditions (25 to 68 GPa; 1350 to 2000 K). Our main observation indicates that magnesite is not stable at shallow lower mantle conditions. At 25 GPa and under oxidizing conditions, melting of magnesite is observed in multi-anvil experiments at temperatures corresponding to all geotherms except the coldest ones. Whereas, at higher pressures and under reducing conditions, in our laser-heated diamond-anvil cell experiments, diamond nucleation is observed as a sub-solidus process even at temperatures relevant to the coldest slab geotherms. Our results indicate that magnesite was reduced and formed diamonds when in contact with the ambient peridotite mantle at depths corresponding to the shallowest lower mantle (33 GPa). Thus, we establish that solid magnesite decomposes at depths of ∼700 km as it contacts the ambient mantle. Consequently, the recycling of carbonates will hinder their transport deeper into the lower mantle.</p></div>","PeriodicalId":54614,"journal":{"name":"Physics of the Earth and Planetary Interiors","volume":"355 ","pages":"Article 107238"},"PeriodicalIF":2.4,"publicationDate":"2024-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142006623","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":"Impact of localization and inflation on geomagnetic data assimilation","authors":"K. Gwirtz ,&nbsp;W. Kuang ,&nbsp;C. Yi ,&nbsp;A. Tangborn","doi":"10.1016/j.pepi.2024.107237","DOIUrl":"10.1016/j.pepi.2024.107237","url":null,"abstract":"<div><p>In geomagnetic data assimilation (DA), information on the Earth's core magnetic field is combined with numerical dynamo models to estimate the dynamic state of the deep interior and produce forecasts of future magnetic field variations. We present a series of numerical experiments exploring the use of localization and inflation schemes in an Ensemble Kalman Filter (EnKF) based geomagnetic DA system. Localization and inflation schemes are (often necessary) modifications to ensemble-based DA systems, which can improve performance, particularly when computational expense limits ensemble size (the number of simultaneous model runs). We find that the studied localization and inflation schemes enable small ensembles to not only match, but exceed the performance of a larger ensemble. Detailed analysis of the results show that, without localization and inflation, even the larger ensembles make adjustments during assimilation which are either too strong or too weak, and lead to poorer estimates of the dynamo state and forecast uncertainties. The use of localization and inflation allows one to better control the impact of assimilation on elements of the dynamo state, thus mitigating some of these issues.</p></div>","PeriodicalId":54614,"journal":{"name":"Physics of the Earth and Planetary Interiors","volume":"355 ","pages":"Article 107237"},"PeriodicalIF":2.4,"publicationDate":"2024-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0031920124000955/pdfft?md5=43bcc5d6c37c70349093fd2bc6006627&pid=1-s2.0-S0031920124000955-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141932556","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":"Strength, plasticity, and spin transition of Fe-N compounds in planetary cores","authors":"Allison Pease ,&nbsp;Jiachao Liu ,&nbsp;Mingda Lv ,&nbsp;Yuming Xiao ,&nbsp;Katherine Armstrong ,&nbsp;Dmitry Popov ,&nbsp;Lowell Miyagi ,&nbsp;Susannah M. Dorfman","doi":"10.1016/j.pepi.2024.107236","DOIUrl":"10.1016/j.pepi.2024.107236","url":null,"abstract":"<div><p>Elastic and plastic properties of Fe-light element alloys and compounds are needed to determine the compositions and dynamics of planetary cores. Elastic strength and plastic deformation mechanisms and their relationship to electronic properties of ε-Fe₇N₃ and γ'-Fe₄N mixture were investigated by x-ray diffraction and x-ray emission spectroscopy in the diamond anvil cell from 1 bar up to 60 GPa. X-ray diffraction shows that ε-Fe₇N₃ reaches a pressure of 15–20 GPa before undergoing bulk plasticity at a differential stress of 4.4–10.4 GPa. ε-Fe₇N₃ is stronger than γ'-Fe₄N and hcp-Fe which achieve a flow stress of 1.5–3.6 GPa at 10–15 GPa and 2–3 GPa at ∼20 GPa, respectively. X-ray emission spectroscopy shows that a decrease in electronic spin moment begins before and completes after plastic flow onset for each nitride, suggesting that pressure-driven changes in electronic arrangement do not trigger a plastic response although they may modify the strength and plastic behavior of Fe-N compounds. Plastic deformation in ε-Fe₇N₃ and hcp-Fe results in a preferred orientation of (0001) normal to maximum compression, while γ'-Fe₄N develops a maximum in the (110). These observations may be combined with measurements of elasticity to model seismic properties of cores of small planetary bodies such as Mars, Mercury, and the Moon.</p></div>","PeriodicalId":54614,"journal":{"name":"Physics of the Earth and Planetary Interiors","volume":"355 ","pages":"Article 107236"},"PeriodicalIF":2.4,"publicationDate":"2024-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141848168","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":"Source parameter and tectonic implications of small earthquakes originating in South India","authors":"Utpal Saikia,&nbsp;Davin Mathews David","doi":"10.1016/j.pepi.2024.107235","DOIUrl":"10.1016/j.pepi.2024.107235","url":null,"abstract":"<div><p>A data collection of 80 local earthquakes (1.8 &lt; M_L &lt; 3.5) recorded by several seismic stations beneath South India from February 2009 to October 2012 was studied to estimate the source parameter characteristics. The result shows that the seismic moments (<span><math><msub><mi>M</mi><mn>0</mn></msub></math></span>) vary from 8.95<span><math><mo>×</mo><msup><mn>10</mn><mn>11</mn></msup></math></span>to 6.56<span><math><mo>×</mo><msup><mn>10</mn><mn>13</mn></msup></math></span> Nm, while source radii (r) are between 120 and 150 m. The source radius seems to be independent of magnitude and smaller within a major part of the region. This can be due to local earthquakes that may originate in the region from either the brittle shear-failure mechanism on faults or the presence of weakened zones in this region. The estimated stress drops values range from 0.20 to 3 MPa for most of the events and shows an increasing trend with the seismic moment, indicating a wide range of strength of crustal rocks. Few lower crustal event exhibits slightly elevated stress drop (4–10 MPa) values, and these cannot be solely attributed to a single model; instead, it appears that the potential contributing factors vary area wise. The corner (<span><math><msub><mi>f</mi><mi>c</mi></msub></math></span>) and high cut (<span><math><msub><mi>f</mi><mi>max</mi></msub></math></span>) frequency values are bit scattered with the seismic moment, and the possible explanation would be either a complex rupture process or the involvement of a long period spectrum in the component. Both <span><math><msub><mi>f</mi><mi>max</mi></msub></math></span> and <span><math><msub><mi>f</mi><mi>c</mi></msub></math></span> show a decreasing trend against seismic moments, indicating that both are caused by a source process and independent of epicentral distances and focal depths. However, source displacement <span><math><mfenced><mi>D</mi></mfenced></math></span>(0.006 and 0.04 m) and radiated seismic energy (<span><math><msub><mi>E</mi><mi>s</mi></msub></math></span>) increases linearly with the seismic moment and is an indication of the size dependency feature. We established various empirical relationships between source parameters, including M_W - M_L and log(M₀) - M_L and proposed the M_L- M_W relationship for the study region, which is M_W <span><math><mo>∝</mo></math></span> 0.62M_L. Overall, the present study indicates that most source parameters tend to vary with the size of the earthquake and generally follow the global model of small magnitude earthquakes. The information, we gained through this study provides insight into earthquake size, source physics, and that can help the scientific community significantly, to better understand, mitigate, and respond to the seismic hazards posed by earthquakes in the studied area.</p></div>","PeriodicalId":54614,"journal":{"name":"Physics of the Earth and Planetary Interiors","volume":"354 ","pages":"Article 107235"},"PeriodicalIF":2.4,"publicationDate":"2024-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141839986","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":"Simulation of microtextural evolution in omphacite: Ordering transformation kinetics as unexplored archives of slab eclogitization","authors":"Ryo Fukushima ,&nbsp;Tatsuki Tsujimori ,&nbsp;Nobuyoshi Miyajima","doi":"10.1016/j.pepi.2024.107227","DOIUrl":"https://doi.org/10.1016/j.pepi.2024.107227","url":null,"abstract":"<div><p>Earth's subduction zone processes and surface environments are intricately governed by mass transfer phenomena at plate convergent boundaries. The determination of their rates and timings from high-pressure metamorphic rocks (e.g., eclogite), or remnants of ancient convergent boundaries, remains an ongoing challenge. Here, we proposed the potential and versatility of ordering transformation kinetics of omphacite, an essential mineral found in eclogite, as a dynamic recorder of the metamorphic history. Through macroscopic phase-field simulation, we explored the growth of antiphase domains (APDs) in metastable disordered omphacite, discussing the feasibility of constraining metamorphic reaction kinetics based on the size and morphology of omphacite APDs in eclogitized oceanic crust. Our simulation corroborated that omphacite nucleating later during the prograde metamorphism can exhibit an incompletely ordered state with sparsely distributed ordered domains, which suggests their usefulness in estimating the recrystallization timing of the omphacite. Additionally, we confirmed that the APD formation dynamics are significantly influenced by the initial cation configuration of the disordered matrix. This implies the APD morphology in natural omphacite under slab-surface conditions may reflect their precipitation kinetics. These findings provide valuable insights into the microtextural evolution of omphacite due to its ordering transformation, thereby enhancing our ability to interpret morphological features.</p></div>","PeriodicalId":54614,"journal":{"name":"Physics of the Earth and Planetary Interiors","volume":"354 ","pages":"Article 107227"},"PeriodicalIF":2.4,"publicationDate":"2024-07-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0031920124000852/pdfft?md5=31ed937b8cd6e1e8eac118ea2de63b58&pid=1-s2.0-S0031920124000852-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141604873","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":"Hydrogenation of calcite and change in chemical bonding at high pressure: Diamond formation above 100 GPa","authors":"Alexander F. Goncharov ,&nbsp;Huiyao Kuang ,&nbsp;John S. Tse ,&nbsp;Eric Edmund ,&nbsp;Maxim Bykov ,&nbsp;Elena Bykova ,&nbsp;Stella Chariton ,&nbsp;Vitali B. Prakapenka ,&nbsp;Timofey Fedotenko ,&nbsp;Nico Giordano ,&nbsp;Mohamed Mezouar ,&nbsp;Jesse S. Smith","doi":"10.1016/j.pepi.2024.107228","DOIUrl":"https://doi.org/10.1016/j.pepi.2024.107228","url":null,"abstract":"<div><p>Synchrotron X-ray diffraction (XRD) and Raman spectroscopy in laser heated diamond anvil cells and first principles molecular dynamics (FPMD) calculations have been used to investigate the reactivity of calcite and molecular hydrogen (H₂) at high pressures up to 120 GPa. We find that hydrogen reacts with calcite starting below 0.5 GPa at room temperature forming chemical bonds with carbon and oxygen. This results in the unit cell volume expansion; the hydrogenation level is much higher for powdered samples. Single-crystal XRD measurements at 8–24 GPa reveal the presence of previously reported III, IIIb, and VI calcite phases; some crystallites show up to 4% expansion, which is consistent with the incorporation of ≤ 1 hydrogen atom per formula unit. At 40–102 GPa XRD patterns of hydrogenated calcite demonstrate broadened features consistent with the calcite VI structure with incorporated hydrogen atoms. Above 80 GPa, the C<img>O stretching mode of calcite splits suggesting a change in the coordination of C<img>O bonds. Laser heating at 110 GPa results in the formation of C<img>C bonds manifested in the crystallization of diamond recorded by in situ XRD at 300 K and 110 GPa and by Raman spectroscopy on recovered samples commenced with C¹³ calcite. We explored several theoretical models, which show that incorporation of atomic hydrogen results in local distortions of CO₃ groups, formation of corner-shared C<img>O polyhedra, and chemical bonding of H to C and O, which leads to the lattice expansion and vibrational features consistent with the experiments. The experimental and theoretical results support recent reports on tetrahedral C coordination in high-pressure carbonate glasses and suggest a possible source of the origin of ultradeep diamonds.</p></div>","PeriodicalId":54614,"journal":{"name":"Physics of the Earth and Planetary Interiors","volume":"354 ","pages":"Article 107228"},"PeriodicalIF":2.4,"publicationDate":"2024-07-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141604878","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":"Electrical conductivity model for transversely isotropic rocks with interconnected cracks","authors":"Yoshiya Usui","doi":"10.1016/j.pepi.2024.107226","DOIUrl":"https://doi.org/10.1016/j.pepi.2024.107226","url":null,"abstract":"<div><p>The electrical conductivity of subsurface rocks is generally anisotropic. The anisotropy of the subsurface electrical conductivity provides important information on the stress-strain state and geodynamics. To quantitatively interpret anisotropic conductivity structures revealed by electromagnetic surveys, it is essential to use a mixing model considering the anisotropy. Although there exists a mixing model for transversely isotropic rocks with crack-shaped pores, the previous model seems inappropriate in interpreting conductive anomalies revealed by electromagnetic exploration because cracks are assumed to be isolated in the model. Therefore, this study develops a theoretical mixing model for transversely isotropic rocks with mutually interconnected cracks by a statistical approach. The derived mixing model considers the macroscopic tortuosity of a collection of cracks as well as the tortuosity of each crack. The derived model can represent general transverse isotropy and includes the isotropic and parallel models as special cases. I compare the developed model to previously proposed mixing models, showing that the developed model can reproduce a much wider range of anisotropy than the already-existing anisotropic mixing model. By applying the developed model to an example of the anisotropic conductivity in the oceanic upper crust inferred by electromagnetic exploration, I demonstrate that the developed mixing model enables us to quantitatively infer the crack orientation and fluid volume fraction that reproduce significant anisotropic conductivity found by field observations. Furthermore, I compare the developed model to the anisotropic seismic velocity model for fluid-filled cracks.</p></div>","PeriodicalId":54614,"journal":{"name":"Physics of the Earth and Planetary Interiors","volume":"354 ","pages":"Article 107226"},"PeriodicalIF":2.4,"publicationDate":"2024-06-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0031920124000840/pdfft?md5=97fe02e6169550ae880f6fa4076adefe&pid=1-s2.0-S0031920124000840-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141543749","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}