Eruption Mechanisms Research Articles

Alkali activated materials from Tajogaite volcanic ash (La Palma, Spain): a green recovery after the 2021 eruption

The 2021 Tajogaite eruption was marked by intense pyroclastic fallout that covered a substantial portion of La Palma island, with maximum thicknesses in the central-western part. This, combined with lava flows, resulted in widespread damage to public and private properties. In this study, we investigated if volcanic ash from this eruption could serve as a raw material in the synthesis of alkali activated materials (AAMs) and contribute to the construction of eco-friendly buildings and the restoration of those damaged by the eruption. Volcanic ash-based AAMs were synthesized using NaOH and Na2SiO3 as alkaline solutions and by adding metakaolin to enhance ash reactivity and enable processing at ambient temperatures. Lightweight porous AAMs were also produced using H2O2 and metallic aluminum as foaming agents. Chemical, textural, physical, and mechanical analyses on the final products assessed their suitability as environmentally friendly materials to be used in the reconstruction of the island infrastructure, opening new perspectives on recovery actions that can be undertaken after disastrous eruptions. Of all the islands in the Canary Archipelago, La Palma has experienced the highest number of eruptions (8) in historical times, all of which showing considerable similarity in terms of eruptive mechanisms and composition to the most recent Tajogaite event. Although this study investigated fresh Tajogaite ash, similar perspectives can be envisaged for both other recent eruptions at La Palma and other similar volcanic scenarios worldwide.

Crystals and melt inclusions record deep storage of superhydrous magma prior to the largest known eruption of Cerro Machín volcano, Colombia

Abstract Cerro Machín, a volcano located in the northern segment of the Andes, is considered one of the most dangerous volcanoes in Colombia with an explosive record that involves at least five plinian events. Prior studies focused on the last dome-building eruption have suggested the presence of a water-rich mid-crustal magma reservoir. However, no direct volatile measurements have been published and little work has been completed on the explosive products of the volcano. Here, we study the largest known eruption of Cerro Machín volcano which occurred 3600 yr BP producing dacitic pyroclastic fall deposits that can be traced up to 40 km from the vent. Lapilli pumice clasts have a mineral assemblage of plagioclase, amphibole, quartz, and biotite phenocrysts, with accessory olivine, Fe-Ti oxides, and apatite. The occurrence of Fo89-92 olivine rimmed by high Mg# amphibole and the established high-water contents in the magma imply the presence of magma near or at water saturation at pressures >~500 MPa. Measurements of up to 10.7 wt% H2O in melt inclusions hosted in plagioclase and quartz in the 3600 years BP eruption products support the idea that Cerro Machín is a remarkably water-rich volcanic system. Moreover, this is supported by measurements of ~103 – 161 ppm H2O in plagioclase phenocrysts. The application of two parameterizations of water partitioning between plagioclase and silicate melt allows us to use our water in plagioclase measurements to estimate equilibrium melt water contents of 5 ± 1 – 11 ± 2 wt% H2O, which are in good agreement with the water contents we measured in melt inclusions. Results of amphibole geobarometry are consistent with a magma reservoir stored in the mid-to-lower crust at a modal pressure of 700 ± 250 MPa, corresponding to a depth of ~25 km. Minor crystallization in the shallow crust is also recorded by amphibole barometry and calculated entrapment pressures in melt inclusions. Amphibole is present as unzoned and zoned crystals. Two populations of unzoned amphibole crystals are present, the most abundant indicate crystallization conditions of 853 ± 26 °C (1 se; standard error), and the less abundant crystallized at an average temperature of 944 ± 24 °C (1 se). Approximately 18% of the amphibole crystals are normally or reversely zoned, providing evidence for a minor recharge event that could have been the trigger mechanism for the explosive eruption. Plagioclase crystals also show normal and reverse zoning. The moderate Ni concentrations (<1600 μg/g) in the high-Fo olivine xenocrysts suggest that Cerro Machín primary magmas are generated by inefficient interaction of mantle peridotite with a high-silica melt produced by slab melting of basaltic material. Some sediment input is also suggested by the high Pb/Th (>2.2), Th/La (0.3 – 0.4), and low La/Th (<13; relative to mantle array) ratios. Whole rock chemistry reveals heavy rare earth element (HREE) depletion and Sr enrichment that likely formed during the crystallization of garnet and amphibole in the upper part of the mantle or lower portion of the crust, promoting the formation of water-rich dacitic magma that was then injected into the middle-to-lower crust. Textural and compositional differences in the crystal cargo that erupted during dome-building and plinian events support the idea that large volumes of magma recharge lead to effusive eruptions, while only small recharge events are needed to trigger plinian eruptions at Cerro Machín.

Zygoma Implant-based Rehabilitation of Three Patients with Primary Failure of Eruption of Teeth - A 5-year Follow-up.

Primary failure of eruption (PFE) is a rare non-syndromic condition in which non-ankylosed teeth fail to erupt fully or partially due to malfunction of the eruption mechanism. 3 young patients are presented in this article with features consistent with a diagnosis of primary failure of eruption. The features of this condition are described together with different modalities of treatment planning for such patients. Zygoma implants as a new approach in the treatment of patients with primary failure of eruption requiring full mouth rehabilitation is discussed.

Syn and post-glacial volcanic activity in the western retroarc area of the andean southern volcanic zone: Overo volcano

Located in a poorly studied zone of the rear arc in the Transitional Southern Volcanic Zone, the Overo volcano presents a complete record of syn-glacial, inter-glacial, and post-glacial activity, marked by significant changes in eruptive mechanisms over time. Following pre-glacial units, an effusive syn-glacial basaltic phase was succeeded by an extensive inter-glacial diking that fed andesitic monogenetic fields. Subsequently, an eruptive pulse, possibly coupled with the destabilization of the main edifice, resulted in a block and ash deposit channeled into a glacial valley towards the southwest, later covered by extensive basaltic lava flows. Then, different types of pyroclastic flows and glacial deposits covered these earlier units. Finally, these younger glacial deposits were overlain by a localized postglacial pyroclastic deposit and widespread lava flows, which ultimately reconstructed the deeply eroded glacial morphology of the Overo volcano. This volcanic record reveals the young and complex activity of this poorly known western rear-arc volcanic center in the Transitional Southern Volcanic Zone of the Andes, whose evolution is more akin to the arc front volcanoes to the west than to their eastern within-plate counterparts. We propose that this magmatic evolution was influenced by the Pleistocene-Holocene Last Glacial Maximum activity (LGM), beginning with an initial phase of volcanic activity encapsulated within glacial conditions. Glacial retreat then triggered isostatic uplift and crustal relaxation, resulting in dike formation, flank instability, and syn-eruptive collapse of the volcanic edifice. Subsequently, a lesser glacial pulse partially eroded the volcano morphology and produced the currently preserved glacial deposits. Finally, a latest and limited post-glacial pyroclastic eruption occurred simultaneously with the formation of an extensive monogenetic basaltic field, shaping the final morphology of the volcano.

How do teeth erupt?

The development of normal occlusion requires eruptive migration of teeth from their developmental position in the jaw into a functional position within the oral cavity. This process involves significant and coordinated movement in an axial direction and appropriate eruption through the gingival tissues. The mechanisms regulating these developmental events are poorly understood, and teeth retain eruptive potential throughout their lifespan. In recent years, the use of mouse models has helped to elucidate some of the underlying molecular and biological mechanisms of mammalian tooth eruption. Here, we outline our current understanding of tooth eruption mechanisms and discuss their relevance in terms of known human disorders of tooth eruption.

High-resolution Observation and Magnetic Modeling of a Solar Minifilament: The Formation, Eruption, and Failing Mechanisms

Minifilaments are widespread small-scale structures in the solar atmosphere. To better understand their formation and eruption mechanisms, we investigate the entire life of a sigmoidal minifilament located below a large quiescent filament observed by Big Bear Solar Observatory/Goode Solar Telescope on 2015 August 3. The Hα structure initially appears as a group of arched threads, then transforms into two J-shaped arcades, and finally forms a sigmoidal shape. Solar Dynamics Observatory (SDO)/Atmospheric Imaging Assembly observations in 171 Å show that two coronal jets occur around the southern footpoint of the minifilament before the minifilament eruption. The minifilament eruption starts from the southern footpoint, then interacts with the overlying filament and fails. The aforementioned observational changes correspond to three episodes of flux cancellations observed by SDO/Helioseismic and Magnetic Imager. Unlike previous studies, the flux cancellation occurs between the polarity where the southern footpoint of the minifilament is rooted and an external polarity. We construct two magnetic field models before the eruption using the flux rope insertion method and find a hyperbolic flux tube above the flux cancellation site. The observation and modeling results suggest that the eruption is triggered by the external magnetic reconnection between the core field of the minifilament and the external fields due to flux cancellations. This study reveals a new triggering mechanism for minifilament eruptions and a new relationship between minifilament eruptions and coronal jets.

A translithospheric magmatic system revealed beneath Changbaishan volcano

Abstract Changbaishan volcano (CBV), located on the border between China and North Korea, has undergone violent eruptions since the Oligocene, making it one of the most captivating and explosive volcanoes on Earth. However, the lack of precise characterization regarding the magmatic system makes it difficult to decipher its eruption risk and mechanism, despite its significant size and past devastating effects. In this study, we employed newly developed teleseismic receiver function techniques, including Ps and Sp waves, to construct a lithospheric structure model beneath the CBV region. The results show a thick crust (~37 km) and a weak, thin lithosphere under the CBV, with a low-amplitude width of 80 km at the Moho depth and 200 km at the depth of the lithosphere-asthenosphere boundary. These features depict the seismological response of a translithospheric magmatic system beneath the CBV, where hot upwelling material rises through the lithospheric mantle, underplates at the base of the crust, and forms the magma chamber(s) at shallow depth. Such magmatic system features can be taken as a unifying paradigm for large volcanic regions worldwide.

Solar magnetic flux rope identification with GUITAR: GUI for Tracking and Analysing flux Ropes

Modelling the early evolution of magnetic flux ropes (MFRs) in the solar atmosphere is crucial for understanding their destabilization and eruption mechanism. Identifying the relevant magnetic field lines in simulation data, however, is not straightforward. In previous work an extraction and tracking method was developed to facilitate this task. Here, we present the corresponding graphical user interface (GUI), called GUITAR (GUI for Tracking and Analysing flux Ropes), with the aim to offer a variety of tools to the community for identifying and tracking MFRs. The starting point is a map of a selected proxy parameter for MFRs, e.g., a map of the twist-parameter Tw, current density, etc. We showcase how the GUITAR tools can be used to disentangle a multi-MFR system and facilitate in-depth analysis of their properties and evolution by applying them on a time-dependent data-driven magnetofrictional model (TMFM) simulation of solar active region AR12473. We show the MFR extraction using Tw maps, together with targeted use of mathematical morphology algorithms and discuss the evolution of the system.

Interpretasi Mekanisme Erupsi Gunung Api Lokon berdasarkan Aktivitas Kegempaan Pra-Erupsi 4 – 12 September 2014

Prior to the eruption of Lokon Volcano on September 13 2014 at 03.09 WITA, there were 62 volcanic earthquake events recorded by seismometers since September 4 2014. This research aims to interpret the eruption mechanism of Lokon Volcano based on seismic activity in the pre-eruption period. 04 - 12 September 2014. The distribution of source points for volcanic earthquakes, both hypocenters, can be visualized using the seismic method, namely by processing digital seimogram data using Swarm 3.1.0 software, GAD (Geiger's method with Adaptive Damping) and Origin 8. Data used, sourced from three stations, namely, Empung (EMP), Wailan (WLN), Kinilow (KIN). Lokon volcano. The hypocenter distribution of volcanic earthquakes is concentrated at a depth of 0 - 1,500 m above sea level and it was found that the aseismic area which is assumed to be a shallow magma pocket area from the Lokon volcano is at a depth of 1,500 - 3,000 m above sea level. The interpretation results show that the eruption mechanism of Lokon Volcano originates from disturbances in the volcanic system which are thought to be the result of tectonic earthquakes in the subduction zone. This causes the magma to rise upwards to supply shallow magma pockets until it reaches maximum pressure and an eruption occurs.

Solar Eruptions in Nested Magnetic Flux Systems

The magnetic topology of erupting regions on the Sun is a key factor in the energy buildup and release, and the subsequent evolution of flares and coronal mass ejections (CMEs). The presence/absence of null points and separatrices dictates whether and where current sheets form and magnetic reconnection occurs. Numerical simulations show that energy buildup and release via reconnection in the simplest configuration with a null, the embedded bipole, is a universal mechanism for solar eruptions. Here we demonstrate that a magnetic topology with nested bipoles and two nulls can account for more complex dynamics, such as failed eruptions and CME–jet interactions. We investigate the stalled eruption of a nested configuration on 2013 July 13 in NOAA Active Region 11791, in which a small bipole is embedded within a large transequatorial pseudo-streamer containing a null. In the studied event, the inner active region erupted, ejecting a small flux rope behind a shock accompanied by a flare; the flux rope then reconnected with pseudo-streamer flux and, rather than escaping intact, mainly distorted the pseudo-streamer null into a current sheet. EUV and coronagraph images revealed a weak shock and a faint collimated outflow from the pseudo-streamer. We analyzed Solar Dynamics Observatory and Solar TErrestrial RElations Observatory observations and compared the inferred magnetic evolution and dynamics with three-dimensional magnetohydrodynamics simulations of a simplified representation of this nested fan-spine system. The results suggest that the difference between breakout reconnection at the inner null and at the outer null naturally accounts for the observed weak jet and stalled ejection. We discuss the general implications of our results for failed eruptions.

Magma flux variations triggering shallow-level emplacement of the Takidani pluton (Japan): Insights into the volcanic-plutonic connection

Defining the physico-chemical evolution of felsic magmatic reservoirs in the middle-upper continental crust is crucial for understanding the connection between granitic plutons and silicic volcanic rocks and for research on the trigger mechanisms of volcanic eruptions. In this study, we investigate the formation and evolution of the Hotaka-Takidani volcano-plutonic complex (Japan) using a comprehensive approach that integrates zircon petrochronology with phase-equilibria and thermal modelling. The Takidani pluton is a Pleistocene tilted zoned intrusion of granodiorite-granite composition associated with at least two large caldera-forming eruptions. We have investigated the three uppermost units of the pluton and the oldest and more voluminous Nyukawa eruption, which deposited more than 400 km3 (DRE, dense rock equivalent) of crystal-rich dacitic ignimbrite. Amphibole thermobarometry, U-Pb zircon dates and geochemical data indicate that the Takidani pluton and the Nyukawa dacite were sequentially sourced from a 10–12 km-thick long-lived magmatic reservoir in the middle crust. Thermal evolution of the reservoir led to the extraction of the Nyukawa magma, followed by brief storage in the upper crust and eruption at ca. 1.706 ± 0.091 Ma. For two of the units of the pluton, we combine high-spatial resolution zircon U-Pb geochronology with zircon chemical data. Applying the Ti-in-zircon thermometer, we observe that magma within the reservoir was stored at a relatively constant temperature of ca. 700 °C for 300 kyr and subsequently, starting from 1.4 Ma, the temperature increased progressively reaching 820–850 °C at 1.1 Ma. This temperature shift is inconsistent with a constant magma flux and suggests an increase of the magma injection rate into the reservoir. Using the distribution of zircon ages and thermal simulations, we determined that the reservoir was built by a fairly low average magma flux of ca. 6 × 10−6 km3*km−2*yr−1, shifting to a magma supply rate which is three to four times higher during the last 300 ka of zircon crystallisation. This increase in magma flux caused the final emplacement of the Takidani magma in the upper crust, where it rapidly crystallized. The integration of geochronological data with phase-equilibria and thermo-chemical modelling demonstrates that multiple melt extraction events occurred during the evolution of the Hotaka-Takidani magmatic system. Only the first one triggered a major eruption, while subsequent events resulted in the emplacement of the Takidani pluton in the shallow crust.

Challenges in block-and-ash flow hazard assessment: The July 10–11, 2015 eruption of Volcán de Colima, Mexico

On July 10 and 11, 2015, Volcán de Colima, one of the most active Mexican volcanoes, underwent its largest eruption since the 1913 Plinian event. Highly mobile block-and-ash flows (BAF) originated from the dome collapse and subsequent extrusion of bubble gas-rich magma from the conduit. The volume and runout of flows were at least one order of magnitude higher (106 m3) than the events observed previously in the 2004–2005 eruptive episode (105 m3) and only comparable with the pyroclastic density currents emplaced during the Vulcanian eruptive phase that preceded the 1913 Plinian eruption. The TITAN2D code is here used to understand the factors controlling the mobility of the dense BAF undercurrents emplaced during the 2015 eruption. The selection of different input parameters was based on field data, on the seismic signal of the BAFs recorded by a broadband station located a few meters away from the channel, and by considering the different eruptive mechanisms of the July 10 eruptive phase (collapsing dome) with respect to the July 11 event (rapid extrusion of degassed magma directly from the conduit). A collapsing pile best fits the July 10 BAF, with an initial spread on the proximal reach and subsequent emplacement along the Montegrande ravine. Instead, for the July 11 BAF, an influx source best replicates the observed distribution, including the overspilling down the San Antonio ravine at the middle reach and the aggradation at the final depositional fan. Both events were better reproduced with the Voellmy-Salm rheology with respect to the Mohr-Coulomb model. Still, the mobility of the July 11 BAF was controlled mainly by the channel reduced capacity due to the 10 July BAF infilling. This was assessed by modeling the 11 July BAF on the real terrain and on a DEM whose altitude was modified based on the maximum flow depth obtained from the simulation of the former flow. Deep knowledge of the eruptive mechanism and flow behavior during the 2015 eruption allowed us to understand the main factors controlling concentrated pyroclastic density current mobility during sustained, multi-phase eruptions, especially for valley-confined BAF. The results presented here set the basis to improve the hazard zonation for pyroclastic density currents at Volcán de Colima, which should be based on a multifactor, probabilistic analysis.

TMEM119 (c.G143A, p.S48L) Mutation Is Involved in Primary Failure of Eruption by Attenuating Glycolysis-Mediated Osteogenesis.

Primary failure of eruption (PFE) is a rare oral disease with an incidence rate of 0.06%. It is characterized by abnormal eruption mechanisms that disrupt tooth eruption. The underlying pathogenic genetic variant and mechanism of PFE remain largely unknown. The purpose of this study was to explore the role of a novel transmembrane protein 119 (TMEM119) mutation in two PFE patients in a Chinese family. Information collection was performed on the family with a diagnosis of PFE, and blood samples from patients and healthy family members were extracted. Whole-exome sequencing was performed. Bioinformatics analysis revealed that a heterozygous variant in the TMEM119 gene (c.G143A, p.S48L) was a disease-associated mutation in this family. Recombinant pcDNA3.1 plasmid-containing wild-type and mutant TMEM119 expression cassettes were successfully constructed and transfected into MC3T3-E1 cells, respectively. The results of in vitro analysis suggested that the subcellular distribution of the TMEM119 protein was transferred from the cell cytoplasm to the nucleus, and the ability of cells to proliferate and migrate as well as glycolytic and mineralized capacities were reduced after mutation. Furthermore, rescue assays showed that activating transcription factor 4 (ATF4) overexpression rescued the attenuated glycolysis and mineralization ability of cells. Results of in vivo analysis demonstrated that TMEM119 was mainly expressed in the alveolar bone around the mouse molar germs, and the expression level increased with tooth eruption, demonstrated using immunohistochemistry and immunofluorescence. Collectively, the novel TMEM119 mutation is potentially pathogenic in the PFE family by affecting the glucose metabolism and mineralized function of osteoblasts, including interaction with ATF4. Our findings broaden the gene mutation spectrum of PFE and further elucidate the pathogenic mechanism of PFE.

Experimental and numerical investigation of a small scale storm sewer geyser

The violent nature of storm sewer geysers has been puzzling researchers worldwide for a very long time. This paper investigates the geyser simulation methodology using a small-scale set-up, where important flow structures such as slugs, eruption patterns, and pressure oscillations are compared with experimental results to test the fidelity of the numerical modelling. In this exercise, a geyser-like process is produced using a continuous insertion of air in the horizontal pipe. The established methodology is used to simulate the hypothesized scenario of a finite trapped air pocket in the relatively longer pipe system. A geyser produced from a finitely trapped air pocket shows a different eruption mechanism compared to those found in previous studies. First, no slug is observed in the horizontal pipe, resulting in continuous air release. Second, the interface continuously atomizes in the vertical pipe, creating a churn-slug flow that produces a large number of small eruptions.

Study of Eruption Mechanism Pyroclastic Deposit of Banten Tuff (Qpvb) in Pancanegara and its surrounding Using Grainsize Distribution and Componentry Analysis

Banten Tuff (Qpvb) is pyroclastic deposit that is very significant in western Java Island. The importance of this deposit is caused by spreading and covering most of Banten region. In the middle of Banten Tuff, there is a caldera that has rectangular shape and the large area 13.7 km x 6.5 km. The research in this area has not studied yet that explain the characteristics of pyroclastics deposit in detail, therefore it’s hard to tell how the eruption process and mechanism that happened based on the deposit. This study become solution of a puzzle about process, mechanism, history, and episode of eruption. The research methods are using qualitative and quantitative analysis such as grain-size distribution and componentry. The study has succeed obtaining more than ten outcrops that described in detail. Description of outcrops resulted tephra-stratigraphy correlation in four facies unit. These four facies categorized into three eruption phases. Eruption phases are arranged into a story which is useful for determining historical and episode eruption in Pancanegara and its surrounding.

Proteomic Analysis of Gingival Crevicular Fluid During Tooth Eruption

Objective: Gingival crevicular fluid (GCF) is a biological fluid that has the unique capacity to reflect changes in periodontium to its protein composition, making it ideal for potential biomarkers. There is limited information about the mechanism of tooth eruption, for which GCF might provide valuable knowledge. This study aimed to provide a proteomic approach to investigate the composition of GCF obtained from two different supraosseous tooth eruption stages of permanent molars changes.
 Methods: GCF samples were taken from a total of 26 healthy children, whose permanent molar just emerged from the gingiva (5-8 years old) and the occlusal equilibrium stage (9-13 years old). Proteins were extracted with Bio-Rad Rehydration Buffer followed by ZebaTM Spin Desalting Column. GCF samples were separated with two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) followed by mass spectrometry- based protein identification.
 Results: A new optimized protocol with enriched protein extraction from GCF samples was developed. Several proteins related to tooth eruption were detected. It was determined that keratin type II cytoskeletal 4 and keratin type I cytoskeletal 9 decreased and albumin increased in GCF protein content in erupting teeth compared to those in the occlusal equilibrium phase.
 Conclusion: This methodology, which we have applied for 2D-PAGE of GCF, can also be a source for other studies. There is huge diagnostic potential in mass spectrometry technologies, this study can be carried forward by using other approaches.

Rapid Fabrication of Efficient and Stable Microporous Electrodes for Practical Alkaline Water Electrolysis

Efficient and stable electrode is paramount for advancing practical alkaline water electrolysis (AWE) technology. In this study, we employed a rapid and scalable laser texturing process to create microporous nickel electrodes, demonstrating promising catalytic performances for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). The alkaline electrolyzer cell (AEL) incorporating laser-textured electrodes (NP-LT30) exhibited a remarkable improvement, with voltage drops exceeding 300 mV under a current density of 1 A cm−1, compared to conventional perforated Ni plate electrodes (NP) based cell. This enhancement resulted from a substantial boost in mass transport, as unveiled by in-situ electrochemical impedance analysis. Of particular note is the unique multi-channel porous structure within the NP-LT30 electrode, enabling rapid mass transport through an innovative convection mode driven by an intermittent bubble eruption (IBE) mechanism, outperforming the traditional convection mode. Furthermore, AEL using NP-LT30 electrodes demonstrated exceptional durability, maintaining performance at 1.0 A cm–2 for an impressive 300 hours. This study highlights the capability of the multi-channel structure within NP-LT30 electrodes to expedite mass transport in practical AWE applications significantly. Moreover, the cost-effective and scalable nature of laser-textured porous electrodes positions them for commercialization, enabling the production of highly efficient electrodes for practical AWE implementation.

Observing white dwarf tidal stripping with TianQin gravitational wave observatory

ABSTRACT Recently discovered regular X-ray bursts known as quasi-periodic eruptions have a proposed model that suggests a tidal stripping white dwarf inspiralling into the galaxy’s central black hole on an eccentric orbit. According to this model, the interaction of the stripping white dwarf with the central black hole would also emit gravitational wave signals, their detection can help explore the formation mechanism of quasi-periodic eruptions and facilitate multimessenger observations. In this paper, we investigated the horizon distance of TianQin on this type of gravitation wave signal and found it can be set to 200 Mpc. We also find that those stripping white dwarf model sources with central black hole mass within $10^4 \!-\! 10^{5.5}\, \mathrm{M}_\odot$ are more likely to be detected by TianQin. We assessed the parameter estimation precision of TianQin on those stripping white dwarf model sources. Our result shows that, even in the worst case, TianQin can determine the central black hole mass, the white dwarf mass, the central black hole spin, and the orbital initial eccentricity with a precision of 10−2. In the optimistic case, TianQin can determine the central black hole mass and the white dwarf mass with a precision of 10−7, determine the central black hole spin with a precision of 10−5, and determine the orbital initial eccentricity with a precision of 10−8. Moreover, TianQin can determine the luminosity distance with a precision of 10−1 and determine the sky localization with a precision of 10−2–10 $\rm deg^2$.

Preliminary magnetotelluric investigation of crustal magma plumbing system beneath the Wulanhada volcanic field, northern China: Implications for the Magma reservoir and pathway

The Wulanhada Volcanic Field (WVF) in northern China consists of a few tens of well-preserved monogenetic volcanoes, where Holocene eruptions have occurred, but is rarely known. Understanding the internal structure of the crustal magma plumbing system beneath the WVF is of great significance for the study of volcanic eruption mechanisms and the assessment of volcanic risks and hazards. We present the crustal electrical resistivity models across the WVF obtained from two-dimensional (2-D) and three-dimensional (3-D) inversion of magnetotelluric profile data, which show some robust and meaningful features. Two high-resistivity anomalies (>1000 Ω·m) occupy almost the entire upper and middle crust. They may serve as an impermeable barrier to impede the ascent of deep magmatic fluids and/or melts. However, there is also a sub-vertical anomaly with moderate resistivity separating two high-resistivity anomalies. We inferred that it may represent a crustal-scale buried fault that provided a pathway for magma ascent during past eruptions and controlled the spatial distribution of the Holocene volcanic group in the WVF. A remarkably high-conductivity anomaly (3–10 Ω·m) in the middle-lower crust is explained to be the presence of ~0.8–7.5% partial melts. It may represent a magma reservoir that exists as a crystal-rich mush zone. Considering the presence of the magma reservoir and pathway beneath the WVF, the volcanic risks and hazards of future eruptions should not be ignored. The results shed light on the structure of the buried volcanic edifice in the WVF and need to be verified by more specific work in the future.

Primary Failure of Eruption: A Diagnosis of Exclusion

Primary failure of eruption is a rare condition, which results in partial or complete failure of a tooth or several teeth to erupt. The postulated cellular process is a malfunction in the eruption mechanism, which fails to completely drive the tooth along its eruption axis. The aetiology is genetic, with a specific link to a mutation in the parathyroid hormone 1 receptor gene, hence a familial pattern of inheritance may be observed. Diagnosis and treatment can be challenging, often necessitating an interdisciplinary approach. CPD/Clinical Relevance: Knowledge of the features of primary failure of eruption is useful for clinicians.