Volcanology

In order to understand the subsurface geology in any geothermal field, drilling is essential. The borehole geologists use the cuttings obtained during drilling to study the subsurface formation so as to identify the lithology, hydrothermal alteration mineralogy and probable location of aquifers. However, it is from the drilled wells that the temperature of the reservoir is measured. With such data, the dynamics of the geothermal system can be evaluated. This paper presents the stratigraphic sequence and the hydrothermal alteration of Wells MW-08 and MW-11, drilled in the Menengai geothermal field. The stratigraphic column is made up of four rock units. They include: pyroclastics, trachyte, tuff and basalt. These dissected rocks conform to the Pre-, Synand Postcaldera volcanic activities that started shortly before 0.18 Ma. The highly altered basalt penetrated by the wells at greater depths is presumed to be older than the caldera and is linked to the pre-caldera volcanics. The main ...

Приведены результаты исследований мульды оседания на стадии формирования. Установлены зависимости положения и величин максимальных оседаний и наклонив земной поверхности от подвигания очистного забоя.The findings of investigation of a subsidence trough at a formation stage are explained. Dependences of position and value of maximum subsidence and tilt from the size of mined-out space are determined

The 17 June 2025 eruption of Mount Lewotobi Laki-Laki (Flores, Indonesia) achieved a record column height of 13,850 masl (VEI-4), making it the first intermediate-scale eruption *ever* documented from a low-elevation coastal location at 250 km distance (Kupang Bay). This study combines real-time PVMBG reports, satellite data (Sentinel-5P, CALIPSO), and ground observations to analyze: 
1. Unprecedented twilight-enhanced visibility mechanisms enabling cross-island observation; 
2. Stratospheric aerosol injection (18.3 km) triggering regional climate anomalies; 
3. Emergency responses to ash dispersal impacting 650 km and 78 flights. 
Validated as a global volcanological benchmark, the event rewrites paradigms on volcanic visibility limits and demands new protocols for archipelagic disaster mitigation.

В работе представлены результаты применения метода геополяритонной томографии (GPTS) для изучения глубинного строения Кемино – Чиликской зоны активных разломов и пространственного распределения гипоцентров сейсмических событий. Полевые исследования, проведённые в сентябре 2024 г. с использованием мобильного комплекса «DSF17A», позволили получить данные с пространственным разрешением около 4.5 м на 83- километровом профиле по маршруту Токмак - Балыкчы. Применена кластеризация гипоцентров вдоль оси разлома, подтверждающая структурный контроль сейсмичности на глубинах 33, 25 и 16 км. Метод демонстрирует хорошие результаты в обнаружении мест тектонических напряжений и анализе сейсмических угроз в сейсмически активных областях. Проведено уточнение механизма формирования взбросовых структур во фронтальных зонах горных хребтов, обусловленного сдвиговыми деформациями в их центральных сегментах. На основе полученных результатов подтверждена модель, согласно которой Кунгейский и Заилийский хребты интерпретируются как элементы «цветочной структуры».

El Malpais National Monument in New Mexico, USA, is a landscape of significant cultural and geological importance, characterized by extensive lava flows, caves, and cinder cones. Despite its harsh terrain, El Malpais holds deep cultural and spiritual meanings for Native American communities, including the Acoma, Zuni, Laguna, and Navajo tribes, whose cosmologies and histories are interwoven with this landscape. Employing a mixedmethods approach combining ethnographic fieldwork with comparative literature studies, this paper documents how these Indigenous groups perceive and interpret interconnected geological features as sacred and meaningful parts of their ancestral heritage. The findings reveal that volcanic landscapes are central not only to cultural origin narratives but also to ongoing rituals, resource use, and pilgrimage practices. This interconnectedness is exemplified by the cultural links between El Malpais and adjacent Mount Taylor, highlighting how geological features form a unified sacred geography. This study positions El Malpais as a culturally animated landscape, where Indigenous epistemologies and spiritual relationships with volcanic landforms challenge conventional notions of geoheritage and call for relational, community-informed approaches to heritage management.

HAL is a multi-disciplinary open access archive for the deposit and dissemination of scientific research documents, whether they are published or not. The documents may come from teaching and research institutions in France or abroad, or from public or private research centers. L'archive ouverte pluridisciplinaire HAL, est destinée au dépôt et à la diffusion de documents scientifiques de niveau recherche, publiés ou non, émanant des établissements d'enseignement et de recherche français ou étrangers, des laboratoires publics ou privés.

Itinerari geologico-naturalistici nelle aree vulcaniche campane: un'opportunità per conoscere e valorizzare un paesaggio naturale e culturale unico. INTRODUZIONE Questo lavoro propone quattro percorsi geoturistici a tema nello straordinario mondo dei paesaggi vulcanici campani, lungo la costa del Tirreno, per scoprire la notevole geodiversità e biodiversità che in un territorio dal ricco patrimonio naturale, scientifico e culturale quale la Campania, è possibile sperimentare. Il nostro percorso è un viaggio di scoperta con occhi nuovi che, attraverso l'osservazione delle morfologie e delle peculiarità naturalistiche degli ambienti vulcanici proposti, ci permette di comunicare con la natura che svela i suoi segreti a chi entra in sintonia con essa, risvegliando emozioni. Questo lavoro ha altresì come obiettivo la divulgazione delle caratteristiche geologico-naturalistiche dei molteplici ambienti dei rilievi vulcanici campani, anche perché la crescente frequentazione dei luogh...

Vengono presentati e discussi i risultati ottenuti a seguito di una campagna spettroradiometrica effettuata nel giugno 2003 sul Monte Etna. Scopo della campagna era quello di realizzare una prima indagine sulle caratteristiche di riflettanza dei depositi piroclastici recenti prodotti dall'attività eruttiva 2002-2003 e sulle colate più antiche. A tal fine sono state predisposte delle schede per l'acquisizione dei dati e sono stati selezionati siti rappresentativi delle unità vulcaniche etnee. Dai risultati ottenuti si evince che i depositi piroclastici recenti, indipendentemente dalla granulometria e dal tipo di materiale che li costituisce, presentano valori di riflettanza costanti. Le colate di tipo pahoehoe hanno valori di riflettanza maggiori, sebbene la caratterizzazione spettrale delle colate più antiche non possa prescindere dalla presenza di prodotti di alterazione e delle coperture vegetali che ne influenza l'entità.

Mount Tambora (+2851m) which was catastrophically erupted in 1815 is the one of the three calderas in Indonesia, which was formed during 750 years and consecutively built up between Mount Rinjani in 1258 and Mount Krakatau in 1883. The site is situated in Sumbawa Island, West Nusa Tenggara as the product of the collision of Eurasian and Australian plates. This setting creates a high geological diversity and provides an opportunity to be developed as national park. Geologist plays an important role to present accurate information about the volcanic formation and process and about the uniqueness of Mount Tambora to support its lifted status to national park. The geologist of Geological Agency carried out several activities to support these objectives since 1998. The outcome of works consists of surveys, seminars, and the preparation of the legal documents related. The development of national park as an alternative tourism is a new paradigm in Indonesia. The purpose in short term is to obtain the geological database over geodiversity of Indonesia while at a long term, it will contribute to geological hazard mitigation through world-class geoconservation. In 2013, The Indonesian Ministry of Forestry has been demanded some geologists from Geological Agency and other related research institutions to collaborate and had been given an order to generate several assessments regarding its emerging status to become a national park in 2015. The effort to this national park status will supposedly give positive impacts to Mount Tambora as a world site which contributes to assemble education and geotourism values in one protected and conserved area.

Investigador multidisciplinario en temas de naturaleza y culturas. El reciente anuncio del supuesto reconocimiento oficial del "Perro Pastor Chiribaya" como raza nacional ha generado gran expectativa mediática, pero también confusión y desinformación. Este artículo busca precisar, desde una perspectiva científica e histórica, el estado real de la investigación sobre esta antigua raza canina vinculada a la cultura Chiribaya del sur peruano, y exhorta a que el tratamiento de este tipo de hallazgos se haga con mayor seriedad académica. La domesticación de animales en los Andes no se limita a llamas y alpacas. En el extremo sur del Perú, hallazgos arqueológicos evidencian la existencia de un perro utilizado para el pastoreo por los Chiribaya, cultura prehispánica que habitó entre los siglos IX y XIV los valles costeros del actual Moquegua y Tacna. Este "perro pastor Chiribaya" ha despertado el interés de arqueólogos, genetistas y antropólogos, al presentar características fenotípicas y genéticas únicas, distintas de razas caninas modernas. Sin embargo, ante la reciente ola de afirmaciones no verificadas que circulan en redes sociales y medios de prensa, urge establecer los límites entre la evidencia científica y las interpretaciones sin respaldo técnico. Investigaciones dirigidas por la Dra. Sonia Guillén (2006) hallaron más de 40 momias de perros en cementerios especiales en el valle del río Osmore. Estos canes presentaban dimensiones físicas similares: cuerpo más largo que alto, pelaje de tonalidades amarillas a rojizas, orejas caídas y extremidades posteriores tipo liebre, adaptadas a los suelos arenosos de los desiertos costeros. Estos hallazgos, junto a análisis genéticos dirigidos por la Dra. Jane Wheeler, revelaron la existencia de haplotipos únicos en el ADN mitocondrial, lo que respalda su singularidad como linaje autóctono.

Nel tardo pomeriggio di mercoledì 12 gennaio 2011 è iniziata un'attività parossistica al Cratere di SE (CSE) dell'Etna, sviluppatasi in particolare dal cratere a pozzo posto sul fianco orientale del CSE. In questo rapporto sono riportate una breve descrizione dell'attività eruttiva e in seguito le caratteristiche principali del deposito di caduta. L'eruzione è stata preceduta da una ripresa dell'attività stromboliana la sera dell'11 gennaio 2011 al cratere a pozzo. Tale attività, rimasta in prevalenza confinata all'interno del cratere stesso, è continuata discontinuamente fino al tardo pomeriggio del giorno dopo, quando intensità e frequenza delle esplosioni hanno iniziato a crescere producendo lancio di blocchi incandescenti al di fuori dell'orlo craterico. La Figura 1 mostra una sintetica cronologia dell'episodio parossistico . L'attività stromboliana è aumentata ulteriormente dopo le 21:30 GMT (ora locale: GMT+1) dando luogo, poco prima delle 22 GMT, alla formazione di una colonna eruttiva al di sopra del vulcano che è stata sospinta verso SSW dai venti dominanti. La nube ha causato ricaduta di lapilli e ceneri sui fianchi del vulcano e di cenere fino alla linea di costa meridionale della Sicilia. L'attività è stata sostenuta per circa un'ora e mezzo. Intorno alle 23:45 GMT la nube eruttiva si è dissolta e pochi minuti dopo anche l'attività esplosiva è praticamente terminata. Ringraziamenti: Si ringrazia Gaetano Spata per aver raccolto alcuni campioni di cenere. Le informazioni e i dati contenuti in questo documento sono stati forniti da personale dell'Istituto Nazionale di Geofisica e Vulcanologia. Tutti i diritti di proprietà intellettuale relativi a questi dati e informazioni sono dell'Istituto e sono tutelati dalle leggi in vigore. La finalità è quella di fornire informazioni scientifiche affidabili ai membri della comunità scientifica nazionale ed internazionale e a chiunque sia interessato. Si sottolinea, inoltre, che il materiale proposto non è necessariamente esauriente, completo, preciso o aggiornato. La riproduzione del presente documento o di parte di esso è autorizzata solo dopo avere consultato l'autore/gli autori e se la fonte è citata in modo esauriente e completa.

Tephrochronology (the dating of sedimentary sequences using volcanic ash layers) is an important tool for the dating and correlation of sedimentary sequences containing archives and proxies of past environmental change. In addition, tephra layers provide valuable information on the frequency and nature of ash fallout from volcanic activity. Successful tephrochronology is usually reliant on the correct geochemical identification of the tephra which has, until now, been based primarily on the analysis of major element oxide composition of glass shards using electron probe microanalysis (EPMA). However, it is often impossible to differentiate key tephra layers using EPMA alone. For example, the Hekla AD 1947 and 1510 tephras (which are found as visible layers in Iceland and also as ‘crypto-tephra’ microscopic layers in NW Europe) are currently indistinguishable using EPMA. Therefore, other stratigraphic or chronological information is needed for their reliable identification. Raman spe...

Until the initial assessment was conducted at least 12 wells of residents of Jungkare Village, Karanganom Subdistrict, Klaten Regency, Central Java experienced subsidence. Various theories and hypotheses have been put forward by observers and disaster experts to answer the phenomenon. These theories and hypotheses need certainty so that the public can prevent and mitigate the phenomenon. Geological, geophysical, and social studies are participatoryly carried out in the hamlets in Jungkare Village that experience the phenomenon of subsidence wells on the southeast side of Mount Merapi. Preliminary results of the study concluded that (1) the sinking of the well occurred due to the collapse of the well wall due to the unstableness of the well wall; (2) This instability occurs due to the saturation of the building material of the well wall by rising groundwater level, excessive water addition causes the toughness of the wall to disappear, (3) the pattern of subsidence in more detail depending on the geological order, (4) the pattern of subsidence in more detail depending on the depth of the aquifer, the structure of the well mouth, the structure of the well's sedimentation, and the magnitude of mat changes. Researchers recommend; (1) to carry out the subsidy and compaction of wells that have been flooded; (2) strengthen the stability of the well wall by installing concrete buses on the entire well wall; (3) make an alternative pump well with piping.

Wa nym problemem w stomatologii estetycznej jest wytworzenie materia ów o zbli onym do naturalnego z ba wygl dzie i odpowiednio wysokiej wytrzyma o ci mechanicznej. Materia y takie wykorzystuje si do rekonstrukcji koron Wa nym problemem w stomatologii estetycznej jest wytworzenie materia ów o zbli onym do naturalnego z ba wygl dzie i odpowiednio wysokiej wytrzyma o ci mechanicznej. Materia y takie wykorzystuje si do rekonstrukcji koron z bowych zarówno w formie pojedynczych jednostek, jak i uk adów z o onych (mosty protetyczne). Aktualnie do tego typu rekonstrukcji stosuje si w warunkach klinicznych szk o-ceramik z uk adu podstawowego Li 2 O-SiO 2 (IPS e. max CAD), w przypadku której podstawow faz krystaliczn , w ilo ci do 70% , stanowi dwukrzemian litu Li 2 Si 2 O 5 . Materia rekonstrukcyjny IPS e. max CAD ma barw naturalnych z bów, jest prze wiecalny i charakteryzuje si wytrzyma o ci na zginanie 360-400 MPa. Celem bada by o wytworzenie prze wiecalnej szk o-ceramiki opartej równie na krystalizacji dwukrzemianu litu, ale charakteryzuj cej si podwy szon wytrzyma o ci mechaniczn w stosunku do komercyjnie dost pnych materia ów; takie tworzywa o wysokich parametrach mechanicznych s bardzo przydatne do wytwarzania sta ych protez w formie mostów z o onych z dwóch i wi cej jednostek. Badania ukierunkowano na mody kacj sk adu chemicznego szk a wyj ciowego w taki sposób, aby otrzymane tworzywo szk o-krystaliczne zawiera o podobnie jak IPS e. max CAD dwukrzemian litu jako podstawow faz krystaliczn , przy jednoczesnej poprawie w a ciwo ci mechanicznych, termicznych i chemicznych pozosta ej w tworzywie fazy szklistej. W tym celu do szkie podstawowych wprowadzono wi cej, w stosunku do IPS e. max CAD, takich sk adników jak CaO, Al 2 O 3 i ZrO 2 . W przypadku tworzyw szk o-krystalicznych wzbogaconych w CaO lub Al 2 O 3 nie zaobserwowano istotnych zmian w asno ci w porównaniu z IPS e. max CAD; natomiast wyra n popraw parametrów wytrzyma o ciowych uzyskano w przypadku tworzyw wzbogaconych w ZrO 2 (wytrzyma o na zginanie oko o 470 MPa). Ponadto tworzywo wzbogacone w ZrO 2 charakteryzowa o si bardzo dobra mikrostruktur i wymagan dla tego typu zastosowa prze wiecalno ci . S owa kluczowe: tworzywo szk o-krystaliczne, kierowana krystalizacja szk a, dwukrzemian litu, IPS e. max. CAD An important issue in the dentistry is to produce materials both similar to natural tooth appearance and having high mechanical properties. Presently commercially available materials are used for reconstruction of tooth crowns, both as individual units and complex systems (bridges restorations). For this type of reconstruction the material of glass-ceramic system Li 2 O-SiO 2 base is used, where Li 2 Si 2 O 5 (lithium disilicate) in an amount of up to 70% is the primary crystalline phase. IPS e. max CAD is currently in use as the material for such reconstructions. It has the color of natural teeth: it is translucent and its bending strength is 360-400 MPa. The aim of our research is to produce translucent glass-ceramic also based on the crystallization of Li 2 Si 2 O 5 but with improved mechanical strength when compared to commercially available materials. Such materials with high mechanical properties are very useful for the preparation of permanent implants in the form of bridges consisting of two and more units. Our research was directed to modify the chemical composition of patent glass in such a way that the new material would also contain Li 2 Si 2 O 5 (lithium disilicate) as the primary crystalline phase, but in the same time improving the mechanical, thermal and chemical properties of the remaining glassy phase in the material. For this purpose, the dopes such as CaO, Al 2 O 3 and ZrO 2 were introduced to the chemical composition in amounts bigger than for IPS e. max CAD. In the case of glass-crystalline materials enriched in CaO or Al 2 O 3 there was no signi cant change of properties compared with IPS e. max CAD, while a marked improvement in the strength parameters was obtained for ZrO 2 -rich materials ( exural strength about 470 MPa). In addition, the material enriched in ZrO 2 was characterized with a very good microstructure and translucency required for this type of application.

at Manoa, Chang has been teaching at the UH School of Law for 37 years. He specializes in water rights, Native Hawaiian rights, the legal history of Hawaii and conflict of laws. The most important two words of Gov. David Ige's speech of May 27 on Mauna Kea were the words "host culture." "I believe our core values need to be: 1. The importance of respecting our host culture," the governor said, in part. How does one respect a "host culture?" Well, what is a "host?" A host is the family or group that gives a party, or the bride and groom who host a reception, or any organization, reunion class, gang of workers that hosts a celebration. The host usually provides the place, food and drink, entertainment and an atmosphere of friendship and good times.

The use of non-condensable gases to identify reservoir processes in vapor-dominated fields is illustrated in a study ofthe changes observed in the steam ofthe NCPA field at The Geysers, California. Variations of gas ratios in the produced steam explain processes resulting from large-scale production and from an increasing amount of injected liquid, especially after the South East Effluent Pipeline came on line. Changes in the source (i.e., chemical characteristics) of the inj ectate are useful in the detection of the various phenomena occurring in the reservoir.

HAL is a multi-disciplinary open access archive for the deposit and dissemination of scientific research documents, whether they are published or not. The documents may come from teaching and research institutions in France or abroad, or from public or private research centers. L'archive ouverte pluridisciplinaire HAL, est destinée au dépôt et à la diffusion de documents scientifiques de niveau recherche, publiés ou non, émanant des établissements d'enseignement et de recherche français ou étrangers, des laboratoires publics ou privés.

A lengthy period of eruptive activity from the summit craters of Mt. Etna started in January 2011. It culminated in early December 2015 with a spectacular sequence of intense eruptive events involving all four summit craters (Voragine, Bocca Nuova, New Southeast Crater, and Northeast Crater). The activity consisted of high eruption columns, Strombolian explosions, lava flows and widespread ash falls that repeatedly interfered with air traffic. The most powerful episode occurred on 3 December 2015 from the Voragine. After three further potent episodes from the Voragine, activity shifted to the New Southeast Crater on 6 December 2015, where Strombolian activity and lava flow emission lasted for two days and were fed by the most primitive magma of the study period. Activity once more shifted to the Northeast Crater, where ash emission and weak Strombolian activity took place for several days. Sporadic ash emissions from all craters continued until 18 December, when all activity ceased. Although resembling the summit eruptions of 1998-1999, which also involved all four summit craters, this multifaceted eruptive sequence occurred in an exceptionally short time window of less than three days, unprecedented in the recent activity of Mt. Etna. It also produced important morphostructural changes of the summit area with the coalescence of Voragine and Bocca Nuova in a single large crater, the "Central Crater", reproducing the morphological setting of the summit cone before the formation of Bocca Nuova in 1968. The December 2015 volcanic crisis was followed closely by the staff of the Etna Observatory to monitor the on-going activity and forecast its evolution, in accordance with protocols agreed with the Italian Civil Protection Department.

This report describes the synthesis of the coordination compounds indicated, both the experimental procedure and the techniques used for their respective characterization, the analytical methods for the qualitative and quantitative determination of each compound, as well as the infrared characterization Spectroscopy, diffraction of X-ray and Raman Spectroscopy.

Large volcanic eruptions can have a substantial impact on climate across the globe. These climatic disturbances can, in turn, have severe human consequences – often very remote from the original eruption. To understand how such eruptions have impacted history (and may impact society in the future) we need to understand how eruptions, climate and society interact. Recent research has done much to clarify the climatic effects of volcanic activity, particularly relating to summer temperatures, while winter temperatures and the impact of multiple eruptions are the subject of ongoing research. Less well understood (or perhaps less agreed upon) is how human societies interact with such volcanic climate change. Many studies have identified the coincidence of eruption events and human calamities, but often the extent of causality has been less clear. This has left many questions still to be addressed: To what extent can we attribute social impacts to volcanic eruptions? How do different eruptions impact different societies and is there any consistency between these impacts? And why are some societies more or less affected by certain certain eruptions?

To address such questions, this workshop will bring together experts from many different disciplines, studying a variety of geographic regions. The aim is to generate a better understanding of volcano-climate-society interactions and help develop a more robust methodology for attributing social impacts to volcanic climate changes. Presentations, hands-on workshops and roundtable discussions will consider the geophysical evidence for past volcanic eruptions (which informs historical and climatological studies), historical case studies, and key questions relating to volcanoclimate-society interactions. Outcomes will hopefully include a more general understanding of the historic impacts of volcanic eruptions and an improved knowledge of the different factors that mediate the impact climate change on human societies.

Well OW-205 is an appraisal well drilled to open the Olkaria Central Field as well as to cater steam for the Olkaria VII power plant. Permeability in the well is controlled by the NW-SE fault in the west and the Ololbutot fault in the east. These faults facilitate near lateral movement of cold fluids in 1400-2000 m and are responsible for temperature reversals at this depth. Abundance of haematite, fluorite and sphene from 800 m to the bottom of the well (3000 m) has been associated with cooling. Possible processes proposed for causing the cooling conditions include mixing of brine and ca-rich meteoric fluids or mixing of two brines with different chemical composition. Temperature evolution around this area is associated with the NW-SE fault and the rejuvenated Ololbutot fault. In the area around well OW-205 two temperature regimes are found; relatively high paleo-temperatures of about 285°C and a lower temperature regime (225°C). With low temperatures around this well, it may not b...

Well OW-205 is an appraisal well drilled to open the Olkaria Central Field as well as to cater steam for the Olkaria VII power plant. Permeability in the well is controlled by the NW-SE fault in the west and the Ololbutot fault in the east. These faults facilitate near lateral movement of cold fluids in 1400-2000 m and are responsible for temperature reversals at this depth. Abundance of haematite, fluorite and sphene from 800 m to the bottom of the well (3000 m) has been associated with cooling. Possible processes proposed for causing the cooling conditions include mixing of brine and ca-rich meteoric fluids or mixing of two brines with different chemical composition. Temperature evolution around this area is associated with the NW-SE fault and the rejuvenated Ololbutot fault. In the area around well OW-205 two temperature regimes are found; relatively high paleo-temperatures of about 285°C and a lower temperature regime (225°C). With low temperatures around this well, it may not be suitable for production as it was planned initially. Alternative uses such as reinjection are an option since the well is intersecting with a deeper flow path of cooler fluids.

Elastic half‐space models, widely used to interpret displacements and gravity data in active volcanic areas, usually compute the displacement response to dilatational sources that simulate a change in pressure of the magma chamber. Elastic‐gravitational models allow the computation of gravity, deformation, and gravitational potential changes due to pressurized magma cavities and intruding masses together. This type of model takes into account the mass interaction with the self‐gravitation of the Earth through coupling between model equations. We perform a dimensional analysis of the elastic‐gravitational model estimating the magnitude of intrusion mass and coupling effects at the space scale associated with volcano monitoring. We show that the intrusion mass cannot be neglected in the interpretation of gravity changes while displacements are primarily caused by pressurization. Therefore the intrusion of mass, together with the associated pressurization of the magma chamber, produces...

Volcanic activity produces deformation and gravity changes that many times can be used as precursors of future eruptions. Applying geodetic techniques to monitoring activity involves interpretation using deformation models. Usually gravity change data and displacement data are interpreted separately. We show, using modeling of deformation and gravity change data in Long Valley Caldera, California, USA, that this can lead to incorrect interpretations. The results obtained show that displacements and gravity changes must be interpreted together whenever possible and that elastic-gravitational models can be a far more appropriate approximation to problems of volcanic load in the crust than the more commonly used purely elastic models. Therefore it is necessary to change the philosophy normally used to interpret geodetic observations, improving the possibility of predicting future eruptions.

Volcanic activity produces deformation and gravity changes that many times can be used as precursors of future eruptions. Applying geodetic techniques to monitoring activity involves interpretation using deformation models. Usually, the observed changes of the deformation and gravity fields are interpreted seperately, not in a joint inversion. It can be difficult, if not impossible, to interpret the data coherently or correctly in terms of the characteristics of the intrusion or the deflation derived from the gravity changes with purely elastic models, as in the case of Mayon Volcano, Phillipines. We show that elastic-gravitational models can be used to interpret these cases simultaneously leading to a result that is more plausible on the basis of the available information. Thus, we may need to change the philosophy normally used to interpret geodetic observations. Interpretation as proposed in this work can significantly improve the possibility of predicting future eruptions.

Although many deep-seated magma reservoirs have been detected beneath active volcanic systems in Iceland in recent decades, none were detected beneath the 5 volcanic systems on the Reykjanes Peninsula (RP) before the year 2020. This area, close to Iceland's capital Reykjavik, was subject to an unrest period with numerous earthquakes, beginning in December 2019. Using this abundant seismicity to produce tomographic images of the RP, we discovered a high Vp/Vs anomaly below the volcanic system of Fagradalsfjallthe smallest of the 5 systems on the RP. This anomaly is clear on images as early as May 2020 and we interpret it as the top part of the source reservoir of the Fagradalsfjall Volcanic System, which now supplies magma to the eruption that started there on 19 March 2021. From the tomographic images, we infer the roof of the reservoir at ~10 km below the surface of the volcanic system, but it extends much deeper. We interpret the results as magma accumulation in the upper part of the reservoir at least by May 2020, and probably earlier, resulting in slight magma-pressure increase and doming of the reservoir roof. The associated stress changes in the roof triggered several earthquake swarms throughout 2020 and into early 2021. Within the part of the roof closest to the reservoir (between 9-12 km depth) 40 earthquakes occurred during 2020. This number doubled again between 1 January and 19 March 2021, when the eruption began. We interpret the preceding earthquake swarm, which began on 24 February 2021 with an earthquake of M5.6, as being associated with the rupture of the roof of the reservoir and dike-segment injection. We interpret the increased activity on the 14th of March, and its location, as a second rupture and a new dike-segment injection which ultimately lead to the eruption, which is still on-going at the time of writing. The reservoir is the first one detected below any of the volcanic systems on the RP. Furthermore, the reservoir supplies magma to the first eruption on the RP for nearly 800 years and the first eruption in Fagradalsfjall for some 6000 years.

Research Highlights Preliminary results on the mineralogy and chemistry of Sb-mineralization at Philadelphio emphasize the mineral intergrowths and inclusions within stibnite, as observed through SEM-EDS analysis. Discussed with data from Rizana and Gerakario, these findings provide insights into the mineralization processes, with ongoing EPMA and LA-ICP-MS analyses focused on refining the genetic model and investigating key metal compositions.

This study utilizes Unmanned Aerial Vehicles (UAVs) and advanced 3D modeling techniques to monitor and analyze the evolution of a significant landslide in Pyrra, Trikala, following the severe weather event known as Daniel in 2023. Specifically, In September 2023, Greece was impacted by the severe weather event known as Daniel, which led to intense rainfall and caused widespread natural disasters in Thessaly, including extensive landslides and floods (Dimitriou et al.,2024). The village of Pyrra in Trikala was notably affected, experiencing a large-scale landslide. This study focuses on documenting and monitoring this landslide to understand its progression over time. Objectives: The primary objectives of this study was to employ advanced geospatial technologies to capture detailed data on the landslide and to use this data to monitor its evolution. (Highland & Bobrowsky, 2008). By doing so, the study aims to contribute to a better understanding of landslide dynamics and inform future mitigation strategies. Geological setting: The landslide in Pyrra, occurred in an area consisting mainly of Pindus flysch. The failure mechanism of the landslide is a translational slide influenced by pre-existing cracks, the geometry of the slope and dye to the continuous rainfall. Methods: The methodology involves multiple steps. Initially, high-resolution aerial imagery of the landslide area was captured using UAVs. These images were processed using photogrammetric methods, specifically the Structure from Motion (SfM) technique, to create detailed 3D models of the terrain. CloudCompare software was employed to analyze the changes in the landscape by comparing datasets collected at two different times: October 2023 and June 2024. The software's C2C (Cloud-to-Cloud) and M3C2 (Multiscale Model-to-Model Cloud Comparison) methods were used to quantify the displacement of materials and provide a comprehensive assessment of the landslide's evolution. Results: The analysis revealed substantial material displacement and changes in the morphology of the landslide. The generated 3D models offer a detailed visualization of the impacted region, showing significant shifts in terrain and volume changes. Quantitative analysis revealed the extent of material movement and highlighted critical areas of instability.

Tephrostratigraphy is a study used in determining pyroclastics layers,especially those in Ash/Tephrograin-sized, that can be used as a correlational tool to find out the order of sedimentation from one volcanic eruption. Leles Sub-Basinal, Garut, is composed mainly by Quartenary Sediment on the toppest layer and Tertiary Sediment on the bottom (Sunardi,2014). These thing of Garut Basin located in a plateau which is surrounded by volcanic plateau and dominated by lake sediment, and geographically located at low latitudes (Sunardi,2016). Based on the existence of Leles Sub-Basinal which is located on active volcanic complex, followed by its pyroclatics sediments, it is very ideal for this area to be the object of Tephrostratigraphy  Study. Moreover, earlier study was never been done before thoroughly at LelesSub-Basinal area. Based on mineralogical study, the tephroof Leles Sub-Basinal divided to Crystal Tuf, Lithic Tuf,and Vitric Tuf (Schmidt,1981). The commonly found minerals are qu...

Gravity method research has been done in Merapi Volcano area. The data has been measured by BPPTKG Yogyakarta team with the number of point as much as 164 points. The aim of this research are to identify the subsurface structure and locate the position of Merapi Volcano magma chamber, so that a gradient analysis and 2D modelling based on Bouguer anomaly has been done. Gradient analysis apply first horizontal and second vertical gradient that is used to know the location and the type of structure on the research area. The result from this research show Bouguer anomaly with range value around -8.79 mGal to 305.46 mGal. The 2D modelling show Merapi volcano subsurface model that consist of 5 layers with the position of magma chamber is located in the third layer about 3300 m below the Merapi summit or 700 m below the mean sea level. Based on gradient analysis, there is a normal dipfault structure. This faults is indicated to be formed a basin on the Merapi summit toward westward leading...

Gravity-induced pyroclastic density currents (PDCs) can be produced by the collapse of volcanic crater rims or due to the gravitational instability of materials deposited in proximal areas during explosive activity. These types of PDCs, which are also known as "glowing avalanches", have been directly observed, and their deposits have been widely identified on the flanks of several volcanoes that are fed by mafic to intermediate magmas. In this research, the suitability of landslide numerical models for simulating gravity-induced PDCs to provide hazard assessments was tested. This work also presents the results of a back-analysis of three events that occurred in 1906, 1930 and 1944 at the Stromboli volcano by applying a depth-averaged 3D numerical code named DAN-3D. The model assumes a frictional internal rheology and a variable basal rheology (i.e., frictional, Voellmy and plastic). The numerical modelling was able to reproduce the gravity-induced PDCs' extension and deposit thicknesses to an order of magnitude of that reported in the literature. The best results when compared with field data were obtained using a Voellmy model with a frictional coefficient of f = 0.19 and a turbulence parameter ξ = 1000 m s -1 . The results highlight the suitability of this numerical code, which is generally used for landslides, to reproduce the destructive potential of these events in volcanic environments and to obtain information on hazards connected with explosive-related, mass-wasting phenomena in Stromboli Island and at volcanic systems characterized by similar phenomena.

Over the past 9,150 years, at least 9 flank collapses have been identified in the history of La Soufrière of Guadeloupe volcano. On account of the volcano’s current unrest, the possibility of such a flank collapse should not be dismissed in assessing hazards for future eruptive magmatic as well as non-magmatic scenarios. We combine morphological and geophysical data to identify seven unstable structures (volumes ranging from 1 × 106 m3 to 100 × 106 m3), including one that has a volume compatible with the last recorded flank collapse in 1530 CE. We model their dynamics and emplacement with the SHALTOP numerical model and a simple Coulomb friction law. The best-fit friction coefficient to reproduce the 1530 CE event is tan(7°) = 0.13, suggesting the transformation of the debris avalanche into a debris flow, which is confirmed by the texture of mapped deposits. Various friction angles are tested to investigate less water-rich and less mobile avalanches. The most densely populated areas...

This study proposes Jabal Harb in northwestern Saudi Arabia as the historically significant Mount Horeb (Mount Sinai), a pivotal site in biblical and Quranic narratives. By synthesizing Quranic geography, archaeological findings, linguistic analysis, and scholarly research, this paper aims to provide a multidisciplinary argument supporting this identification. The implications of this hypothesis extend to understanding regional history, biblical geography, and Islamic tradition.

Crust at many divergent plate boundaries forms primarily by the injection of vertical sheet-like dykes, some tens of km long 1 . Previous models of rifting events indicate either a lateral dyke growth away from a feeding source, with propagation rates decreasing as the dyke lengthens 2,3,4 , or magma flowing vertically into dykes from an underlying source 5,6 , with the role of topography on the evolution of lateral dykes not clear. Here we show how a recent segmented dyke intrusion in the B ‡r!arbunga volcanic system, grew laterally for over 45 km at a variable rate, with an influence of topography on the direction of propagation. Barriers at the ends of each segment were overcome by the buildup of pressure in the dyke end; then a new segment formed and dyke lengthening temporarily peaked. The dyke evolution, which occurred over 14 days, was revealed by propagating seismicity, ground deformation mapped by Global Positioning System (GPS), interferometric analysis of satellite radar

Morphostructural features are essential for geothermal resource evaluation. They provide insights into geological structures and surface features that are linked to geothermal activity, thus enhancing exploration and resource characterization efficiency. This study assesses a place with recognized geothermal energy via structural lineaments, and morphological environments and geological units using diverse satellite images information and fieldwork resources to define the morphostructural framework of the Valle de Nereidas geothermal field. The results indicate that: 1) heat contribution in the study area is primarily associated with volcanic emission centers and units younger than 2 Ma, extending beyond the Nevado del Ruiz volcanic complex; and 2) fluid circulation and recharge zones correspond to fractured lava flows, where thermal contraction facilitates the infiltration and movement of regional groundwater. These findings suggest that the geothermal system in the Valle de Nereidas is controlled by both volcanic and structural features, where young volcanic edifices act as heat sources, and faulted and fractured zones enhance fluid circulation. Data from the drilled well Nereidas-1, including lithological descriptions, helped to establish relationships between subsurface geology and surface expressions of geothermal activity. These results help to define the spatial distribution of thermal anomalies and recharge areas, which directly impact resource sustainability and reservoir management. Furthermore, they provide valuable information for improving geothermal exploration strategies in the area by refining the model of subsurface heat transport and fluid dynamics.

Time Heritage, Services and Consultancy for Heritage Management, Enhancement and Protection – Greece E-mail: cleopatra.ferla@gmail.com ABSTRACT This paper examines thermalism in Greece both in its historical development and in the context of current challenges engendered by economic recession. The authors’ intention is to discuss bathing in thermal springs as a sociocultural practice deeply rooted in history and collective experience (Erfurt-Cooper & Cooper, 2009), to follow its transformations in the course of time, and to analyze the complexity of its present state. The latter issue, which is dealt with in more detail, is explored through academic literature, the evaluation of quantitative and qualitative data, and empirical research. The last part of the paper discusses the conclusions of our study of the Greek case with a view to contributing to the overall assessment of popular thermalism in Europe.

A general procedure for deriving effective large-scale fluid equations is presented. It is applicable to a large class of non-linear systems. Starting from the original dynamical equations, the formalism determines closed equations governing the large-scale component of the fields. In this way, complex flows can be numerically simulated with moderate computational resources. The procedure is applied to the twodimensional Navier-Stokes equation for incompressible flow and to a decaying one dimensional Burgers flow. The resulting systems are numerically solved on a coarse grid. The solutions are compared to direct numerical simulations of the Navier-Stokes equation and of Burgers equation, which require a much finer grid. The characteristic features of the flow at all stages of its evolution are well reproduced, including a correct energy exchange between large and small scales.

RED SEED stands for Risk Evaluation, Detection and Simulation during Effusive Eruption Disasters, and combines stakeholders from the remote sensing, modelling and response communities with experience in tracking volcanic effusive events. The group first met during a three day-long workshop held in Clermont Ferrand (France) between 28 and 30 May 2013. During each day, presentations were given reviewing the state of the art in terms of (a) volcano hot spot detection and parameterization, (b) operational satellite-based hot spot detection systems, (c) lava flow modelling and (d) response protocols during effusive crises. At the end of each presentation set, the four groups retreated to discuss and report on requirements for a truly integrated and operational response that satisfactorily combines remote sensors, modellers and responders during an effusive crisis. The results of collating the final reports, and follow-up discussions that have been on-going since the workshop, are given h...

The examination of mines and mining prospects at Fort Irwin was done concurrently with Division of Mines and Geology (DMG) regional geologic mapping and other mineral resource studies in the region. Mapping, field checking, and geologic data of the Fort Irwin region were collected between January 1982 and May 1990 . DMG conducted an investigation of the mineral resource potential of the Fort Irwin region to develop geologic and mineral information in a region of California where very little published mineral resource information exists. This article was adapted from an unpublished DMG Special Report that will be entitled The minera l reso urce potential, geology, and abandoned mines of Fort Irwin , San Bernardino County, California .