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Radon-222, 222Rn, is a naturally radioactive noble gas with a half-life of 3.82 days. It is a product of the 238U disintegration chain with 226Ra as parent isotope. Radon gas has traditionally been linked to magmatic and seismic activity.In order to improve volcanic surveillance networks, 222Rn monitoring in volcanic areas is carried out by measuring its concentration in air and soils. Also, since radon-222 is soluble in water, the gas may also be dissolved into groundwater flows. The quantity of dissolved 222Rn depends on different factors such as the characteristics of the aquifer, water-rock interaction, water residence time and material content of radium.In Tenerife there are a vast number of excavated galleries, subhorizontal water mining tunnels, that drain the main aquifer in the island. Thirteen of them have been selected in order to monitor the dissolved radon-222 concentration since October 2019 every three months. This set of galleries surrounds the main volcanic complex in the island, Teide-Pico Viejo, located in Las Cañadas caldera in central Tenerife. Before sampling, 10 ml of Opti-Fluor O scintillation cocktail for selective extraction of radon-222, two-phase counting method, was transferred into a 20 ml vial. During the sampling, 10 ml of water were injected into the bottom of the vial. The vial was then tightly capped, vigorously shaken and transported to the laboratory for analysis. Water samples were measured using the liquid scintillation system Quantulus 1220 from PerkinElmer.In this work, we show the main and preliminary results, which includes both spatial and temporal distribution of the dissolved radon concentration measured in the selected sampling points for the studied period. There are galleries showing a high stability, with radon-222 activity concentrations around 20 Bq/L, whereas others show a clear seasonal influence. The maximum dissolved 222Rn value detected was 29.2 ± 2.1 Bq/L. The detection limit is 0.5 Bq/l using a 30 minutes counting time. Besides, this dataset has been compared to data previously reported by other authors, in order to find changes in dissolved radon-222 emission across time. Finally, in the aim of finding interesting relationships, dissolved 222Rn values have been studied together with in situ groundwater parameters measured in the field (temperature, pH and electric conductivity) and, in some of the sampling points, also with dissolved CO2 concentration and isotopic ratio 3He/4He corrected for air contamination, (R/Ra)c, which are parameters directly related to volcanic activity.

Phreatic and phreatomagmatic eruptions are difficult to predict with accuracy on volcanoes due to complex interactions at depth between heat, water, and magmatic fluids. To better understand such multifaceted interactions, we present here a multidisciplinary geophysical approach performed on Miyakejima, a 10-km wide stratovolcano in the Izu Bonin arc. Its plumbing system was highlighted by combining four geophysical methods: magnetotellurics, seismicity (hypocenters), self-potential, and thermal image (remote sensing). We thus propose the first large-scale interpretation of the volcanic structure in terms of rock properties, temperature, fluid content, and fluid flow. Our findings indicate that hot volatiles released from a deep magmatic reservoir (> 350°C, 2.5–4.5 km depth) rise through a narrow permeable path, interact with the conductive hydrothermal system beneath the 2000 A.D. caldera (

Grenada is the last volcanic island in the Lesser Antilles that has been home to Ocean Spirits, a local NGO who for two decades have been conducting sea turtle research and conservation efforts island-wide. The first opportunities to train as patrol researchers with Ocean Spirits was given to members of the local communities who relied of turtle fishing as a source of income. Tourism in Grenada is an important sector for the local economy. Conducted within appropriate guidelines, turtle-based tourism can be a positive force for the conservation of turtles. Additionally through tourism, the revenue can be spread throughout the surrounding communities.

We present here the first record of plant-insect interactions from an ephemeral volcanic island that was placed 150 km away from the nearest continental mass. The island was formed and destroyed during the Aalenian (Middle Jurassic) in a shallow sea of the southwestern Tethyan realm corresponding today to a place located in eastern Spain. These plant-insect interactions were mainly documented in leaves of Cycadophytes (comprising both Cycads and Bennettitales), and they have been described and classified into different Damage Types (DTs) and Functional Feeding Groups (FFGs). The interactions were assigned to 11 different DTs including different types of hole feeding, margin feeding, surface feeding, piercing and sucking, mining(?), and some putative ovipositional scars. The presence of these interactions implies that the island was colonized by different groups of insects, including orders such as Coleoptera, Hemiptera, Odonata, or Lepidoptera. The low variety and incidence of interactions comparing with other Middle Jurassic plant-insect interactions assemblages indicate that the diversity of insects was not high, possibly due to the difficulty of reaching this island by various lineages, the small size of the landmass of the island, and the limited food availability (mainly Cycadophytes). Possible colonization strategies could be by atmospheric dispersion, using floating remains of plants or pterosaurs as vectors, by active flight for Lepidoptera, or by rafting and floating in marine currents for flightless or other insects. Financiado para publicación en acceso aberto: Universidade de Vigo/CISUG Agencia Estatal de Investigación | Ref. PGC2018-094034-B-C22 Xunta de Galicia | Ref. ED481A-2019/243

Summary Multiple studies focused on eustatic changes during the Cretaceous as an example of greenhouse world. Most of these studies were performed in local areas. These sea level estimates might be derived from localised effects and therefore reflect relative sea level changes rather than eustasy. Based on that, sensitivity analysis to test the applicability of using the Cretaceous ESL curves of Rohl & ogg (1996), Sahagian et al. (1996), Hardenbol et al. (1998), and Haq (2014) is crucial to validate or refute them. To do that, forward stratigraphic modelling of one of the Mid-Pacific mountain guyots, Resolution Guyot, is performed. The study area is unique as it represents deposition of Cretaceous carbonates (growing at sea-level) on an isolated volcanic island away from the influence of continents and tectonic activity. The initial results show that Haq (2014) ESL curve wasn’t perfectly fitting some of our constraints, and some of the cycles need finer subdivision. The outcomes of this study will constrain the fluctuations of ESL in the Cretaceous and serve as a test to whether the amplitude and timing of regionally-derived eustatic curves are valid for other locations, or whether these curves are too influenced by specific local conditions in the areas.

Ischia is a densely inhabited and touristic volcanic island located in the northern sector of the Gulf of Naples (Italy). In 2017, theMw3.9 Casamicciola earthquake occurred after more than one century of seismic quiescence characterized only by minor seismicity, which followed a century with three destructive earthquakes (in 1828, 1881, and 1883). These events, despite their moderate magnitude (Mw< 5.5), lead to dreadful effects on buildings and population. However, an integrated catalogue systematically covering historical and instrumental seismicity of Ischia has been still lacking since many years. Here, we review and systematically re-analyse all the available data on the historical and instrumental seismicity, to build an integrated earthquake catalogue for Ischia with a robust characterization of existing uncertainties. Supported by new or updated macroseismic datasets, we significantly enriched existing catalogues, as the Italian Parametric Earthquake Catalogue (CPTI15) that, with this analysis, passed from 12 to 57 earthquakes with macroseismic parametrization. We also extended back by 6 years the coverage of the instrumental catalogue, homogenizing the estimated seismic parameters. The obtained catalogue will not only represent a solid base for future local hazard quantifications, but also it provides the unique opportunity of characterizing the evolution of the Ischia seismicity over centuries. To this end, we analyse the spatial, temporal, and magnitude distributions of Ischia seismicity, revealing for example that, also in the present long-lasting period of volcanic quiescence, is significantly non-stationary and characterized by a b-value larger than 1.

During the first two days of August 2016 a seismic crisis occurred on Brava, Cabo Verde, which – according to observations based on a local seismic network – was characterized by more than a thousand volcano-seismic signals. Brava is considered an active volcanic island, although it has not experienced any historic eruptions. Seismicity significantly exceeded the usual level during the crisis. We report on results based on data from a temporary seismic-array deployment on the neighbouring island of Fogo at a distance of about 35 km. The array was in operation from October 2015 to December 2016 and recorded a total of 1343 earthquakes in the region of Fogo and Brava; 355 thereof were localized. On 1 and 2 August we observed 54 earthquakes, 25 of which could be located beneath Brava. We further evaluate the observations with regards to possible precursors to the crisis and its continuation. Our analysis shows a significant variation in seismicity around Brava, but no distinct precursory pattern. However, the observations suggest that similar earthquake swarms commonly occur close to Brava. The results further confirm the advantages of seismic arrays as tools for the remote monitoring of regions with limited station coverage or access.

Earthquakes affect near-surface permeability, however temporal permeability evolution quantification is challenging due to the scarcity of observations data. Using thirteen years of groundwater level observations, we highlight clear permeability variations induced by earthquakes in an aquifer and overlaying aquitard. Dynamic stresses, above a threshold value PGV > 0.5 cm s−1, were mostly responsible for these variations. We develop a new model using earth tides responses of water levels between earthquakes. We demonstrate a clear permeability increase of the hydrogeological system, with the permeability of the aquifer increasing 20-fold and that of the aquitard 300-fold over 12 years, induced by fracture creation or fracture unclogging. In addition, we demonstrate unprecedented observations of increase in permeability due to the effect of extreme tropical deluges of rainfall and hurricanes. The water pressure increase induced by the exceptional rainfall events thus act as piston strokes strong enough to unclog congested fractures by colloids, particles or precipitates. Lastly, an analysis of regional permeabilities also highlights a permeability increase over geological timeframes (× 40 per million years), corroborating the trend observed over the last decade. This demonstrates that permeability of aquifers of andesitic volcanic islands, such as the Lesser Antilles, significantly evolve with time due to seismic activity and extreme rainfall.

International audience; The pedological studies carried out so far in Trindade Island (TI) have obtained patchy evidences of allophane, without detailed mineralogical and micromorphological studies to confirm the occurrence of Andosols in TI. Therefore, in this study, the mineralogical, micromorphological, physical and chemical characterization of four soil profiles from Vulcão do Paredão (P1) and Morro Vermelho formations (P2, P3, and P4) were carried on the latest volcanic events in Brazil from Trindade Island (TI) with the aim of to evaluate the presence of Andosols in this oceanic island. Profiles P1 and P2 are developed on pyroclastic bombs, and show, respectively, A-Bi-C and decapitated A-C horizons, whereas P3 and P4 are developed on lapillitic and bomb pyroclasts, show A-C horizons. The soil profiles have a reddish and brownish clayey matrix, are highly friable and show a plastic consistency. Their microstructures are granular, single grain and intergrain microaggregate, in which aggregates display an undifferentiated b-fabric. The mineralogical constituents of the bulk fraction are biotite, hematite, magnetite, ilmenite, pyroxene, olivine, halloysite, goethite, anatase, and rutile. The clay fraction is marked by the presence of halloysite, ferrihydrite, and little amounts of allophane. All soils presented andic properties and can be classified as non-allophanic Andosols. In addition, micromorphological features closely resemble those reported in Andosols from other volcanic islands from elsewhere. The predominance of halloysite in the clay fraction formed by alteration of sideromelane, suggests that allophane would be an intermediate phase of this rapid transformation favored by the wet climate conditions of the highest parts of TI.

The recent paroxysmal crisis occurring on the island of Stromboli (Tyrrhenian Sea, Italy), manifesting into two main events during summer 2019 (3rd July and 28th August), renovated the attention on the possibility of tsunami generation induced by volcanic activity. The Stromboli edifice is characterized by the Sciara del Fuoco scar on its north-western flank channeling most of the material ejected from the crater to the sea.In this area, in December 2002, two landslides (the first submarine, the second subaerial) triggered large waves affecting the whole coast of the island, causing severe damages but fortunately no casualties, due to the non-touristic period. The tsunami rapidly dissipated with distance, being observed in Panarea (20 km south-east of Stromboli), as is typical of non-seismic tsunamigenic sources. A similar occurrence during summer would have resulted into dramatic consequences, especially along the Stromboli coasts.In this study, the tsunamigenic potential associated with destabilized mass along Stromboli flanks is evaluated by means of numerical, in-house developed, codes with the aim of providing insights on the tsunami hazard along the coasts of Stromboli, of the surrounding Aeolian archipelago and in general in a larger domain covering the southern coasts of Tyrrhenian Sea as well.

The formation of the oceanic island Surtsey in the shallow ocean off the south coast of Iceland in 1963-1967 remains one of the best-studied examples of basaltic emergent volcanism to date. The island was built by both explosive, phreatomagmatic phases and by effusive activity forming lava shields covering parts of the explosively formed tuff cones. A detailed gravity survey was carried out on Surtsey in July 2014 with a gravity station spacing of ~100 m. We analyse these data in order to refine a 2.5D-structural and density model of the internal structure for this type locality of Surtseyan volcanism. We carry out a complete Bouguer correction of these data using total terrain corrections based on detailed DEMs of the island and the submarine bathymetry. The principal components of the island are the two tuff cones composed principally of lapilli tuff; this was originally phreatomagmatic tephra formed in the explosive phases of the eruption. Lapilli tuff can be subdivided into (1) submarine lapilli tuff and (2) lapilli tuff above sea level. Other units are (3) subaerial lava, and (4) subaqueous lava deltas. Minor components that are volumetrically insignificant are small intrusions, and unconsolidated and unaltered tephra, still found in thin layers flanking the tuff cones. An additional formation, relevant for any analysis of the subsurface structure of Surtsey, is (5) the sedimentary rocks making up the seafloor, being at least 100 m thick but probably much thicker. Using measurements of the density of all the above components, and subdividing the island into different units based on its pattern of growth, we specifically attempt to constrain the width and depth of diatreme structures proposed by Moore (1985) and confirmed in the ICDP SUSTAIN drilling of Surtsey in 2017 (Jackson et al., 2019). Our forward modeling is aided by a detailed subdivision of the island into units (1) to (4) based on repeated mapping of the island during 1964-1967. Moore, J. G., 1985, Geological Magazine 122, 649–661Jackson, M. D., et al. 2019, Scientific Drilling 25, 35–46.

Chemical profiling of the Streptomyces sp. strain SUD119, which was isolated from a marine sediment sample collected from a volcanic island in Korea, led to the discovery of three new metabolites: donghaecyclinones A&ndash, C (1&ndash, 3). The structures of 1&ndash, 3 were found to be rearranged, multicyclic, angucyclinone-class compounds according to nuclear magnetic resonance (NMR) and mass spectrometry (MS) analyses. The configurations of their stereogenic centers were successfully assigned using a combination of quantum mechanics&ndash, based computational methods for calculating the NMR shielding tensor (DP4 and CP3) as well as electronic circular dichroism (ECD) along with a modified version of Mosher&rsquo, s method. Donghaecyclinones A&ndash, 3) displayed cytotoxicity against diverse human cancer cell lines (IC50: 6.7&ndash, 9.6 &mu, M for 3).

Activity on the volcanic island Taal has eased, but scientists say the threat is far from over. Activity on the volcanic island Taal has eased, but scientists say the threat is far from over.

International audience; The Drosophilid fauna has been less investigated in the Atlantic Afrotropical islands than in the Indian Ocean. Located about 250 km from the continent, the volcanic island of São Tomé has been colonized mostly by natural means, probably by the wind, since the emergence of the island about 15 million years ago, and presumably also by anthropogenic transportation of invasive and domestic species. To date, 37 different Drosophilid species have been mentioned from São Tomé. The present work extends this list to 80 species. The genera Zygothrica, Phorticella and Hypselothyrea are newly recorded from the island. Among these 80 species, only 12 are putatively introduced by human activities, suggesting the preponderance of natural arrivals. Compared to other islands, São Tomé harbours a high diversity of drosophilids. At least 14 species are supposed to be endemic. Future molecular comparisons between the island flies and their continental relatives will probably help to identify other endemic species. The high diversity observed in São Tomé is certainly due to the large size of the island, and to the presence of vast natural altitudinal forests offering a variety of possible habitats. Further collections are likely to lead to an increase of the species list. From now, São Tomé island appears as an excellent laboratory for studying the ecology and evolution of the Drosophila model.; La faune de Drosophilidae a été moins étudiée dans les îles afrotropicales de l’Atlantique que dans l’océan Indien. Située à environ 250 km du continent, l’île volcanique de São Tomé a été colonisée principalement de façon naturelle, probablement à l’aide du vent, depuis l’émergence de l’île il y a environ 15 millions d’années, et par le transport supposé d’espèces domestiques et invasives par l’activité humaine. Jusqu’à présent, 37 espèces de Drosophilidae étaient mentionnées à São Tomé. Le présent travail accroît cette liste à 80 espèces. Les genres Zygothrica, Phorticella et Hypselothyrea sont nouvellement cités de l’île. Parmi ces 80 espèces, seulement 12 pourraient avoir été introduites par les activités humaines, révélant la prépondérance des colonisations naturelles. Comparée à d’autres îles, São Tomé abrite une plus grande diversité de drosophiles. Au moins 14 espèces sont supposées être endémiques. Il est probable que d’autres espèces endémiques seront identifiées lorsque les études moléculaires permettront de comparer les individus de São Tomé avec les espèces apparentées du continent africain. La diversité observée à São Tomé est certainement due à la grande taille de l’île et à la présence d’une vaste forêt d’altitude offrant une grande variété d’habitats. De futures collectes permettront d’accroître la liste d’espèces. L’île de São Tomé apparaît comme un excellent territoire pour l’étude de l’écologie et de l’évolution du modèle drosophile.

This project seeks to recover and record the archaeological evidence associated with the extraction of sulfur (and perhaps other minerals as well) by James Stevenson, a Glasgow industrialist, from the volcanic island of Vulcano, Aeolian Islands, Italy, in the second half of the 19th century. This short preliminary report sets the scene by linking archival material with present conditions and by carrying out select mineralogical analyses of the type of the mineral resource Stevenson may have explored. New 3D digital recording tools (structure-from-Motion photogrammetry) have been introduced to aid future multidisciplinary research. This is a long-term project which aims to examine a 19th-century Scottish mining venture in a southern European context and its legacy on the communities involved. It also aims to view Stevenson’s activities in a diachronic framework, namely as an integral part of a tradition of minerals exploration in southern Italy from the Roman period or earlier.

The Alaskan Aleutian Islands form one of the world’s largest volcanic island chains. The islands are exposed to both direct and indirect damage from continuous volcanic eruptions. Surface deformation is mostly observed before volcanic eruption, but with some volcanoes, such as Ontake Volcano, deformations cannot be detected. In this study, we analyzed volcanic eruptions in the Alaskan Aleutian Islands, which is a region of frequent volcanic eruptions. Based on our results, we predicted the type of eruption that would occur on Baekdusan Volcano according to the presence or absence of surface deformation. For this purpose, 10 sites were selected from areas where recent volcanic activity had occurred in the Aleutian Islands. Additionally, Advanced Land Observing Satellite Phased Array-type L-band Synthetic Aperture Radar (ALOS-PALSAR) and European Remote Sensing (ERS)-1/2 satellite data were obtained from 10 experimental sites. Based on the radar satellite data, the volcanic surface deformations were identified, and the characteristics of the volcanic eruption were quantitatively calculated by determining the presence of surface deformation. The results of this study should facilitate the process of correlation between volcanic eruption and surface deformation.

On 21 August 2017, a shallow earthquake of Md 4.0 struck the CasamicciolaTerme village in the north of Ischia volcanic island (Italy). It caused two fatalities and heavy damage in a restricted area of a few square kilometers. Casamicciola Terme has been recurrently destroyed in the last centuries by similar volcano-tectonic earthquakes (1762, 1767, 1796, 1828, 1881, and 1883). After the catastrophic 1883 Casamicciola event (2343 casualties), this is the first heavy damaging earthquake at Ischia that provides, for the first time, the opportunity of integrating historical seismicity, macroseismic observations, instrumental information, and detailed mapping of coseismic geological effects. Soon after the 2017 mainshock we surveyed the epicentral area to collect data on the coseismic ground effects, recording more than 100 geological field observations. Mapped effects define a belt which closely follows the trace of the Casamicciola E-W-trending normal fault system, bounding the northern slope of Mt. Epomeo, previously known as a Latest Pleistocene to Holocene normal fault with a slip rate of ~3:0 cm=yr. We found significant evidence for coseismic surface faulting, testified by a main alignment of ruptures for a 2 km end-to-end length and normal dip-slip displacement of 1-3 cm. The geometry and regularity of the structural pattern, together with constant kinematics of the coseismic ruptures with the north side down, strongly suggest a primary tectonic origin for the mapped ruptures and strongly supports an E-W normal-faulting focal mechanism for the 2017 Casamicciola earthquake.Macroseismic information supports the notion that previous historical events also had a similar style of faulting.

A deterministic seismic risk and monetary loss model is presented for the capital of Santorini volcanic Island, the town of Fira, on a building block scale. A local seismic source of M5.6 inferred from a recent volcano unrest in 2011–2012, detailed seismic vulnerability of 435 buildings and site conditions deduced from free-field ambient noise measurements were combined toward assessing the EMS-98 damage grade and its probability to occur. The seismic scenario yielded no damage or slight damage for 84% of the buildings, 16% of the constructions are expected to present moderate-to-heavy damage, while the economic loss amounts to 4 million euros. Although the model predicts low damage and direct economic loss, interaction with the touristic business activities might produce cascade side effects for the economy of the island and consequently Greece’s GDP, an important part of which emanates from Santorini.

This article presents evidence for prehistoric rice cultivation on the island of Jeju (Jejudo), Korea. It also discusses sociopolitical contexts in which the people of this island decided to incorporate rice into their lifeways. Although Jejudo is culturally closely related to the southern region of the Korean peninsula, the nearest landmass to the island, their environmental conditions are radically different. Jejudo is not suitable for intensive rice cultivation. Archaeobotanical research at Yerae-dong nonetheless confirmed that rice was consumed earlier than the emergence of institutionalized social hierarchy on the island. The evidence for status competition and exchange networks contemporaneous with rice remains raises the suggestion that rice was initially incorporated as an exotic and luxurious food, rather than a daily necessity. The earliest rice on Jejudo is unlikely to have been transferred to the island as a result of tributary trade between ancient states. Rather, this study demonstrated that the main agents of rice cultivation were the emergent local elites who attempted to express status and consolidate hierarchy with foreign objects.

On September 29, 2009 at 17:48 UTC, an Mw = 8.1 earthquake in the Tonga Trench generated a tsunami that caused heavy damage across Samoa, American Samoa, and Tonga. One of the worst hits was the volcanic island of Tutuila in American Samoa. Tutuila has a typical tropical island bathymetry setting influenced by coral reefs, and so the event provided an opportunity to evaluate the relationship between tsunami dynamics and the bathymetry in that typical island environment. Previous work has come to differing conclusions regarding how coral reefs affect tsunami dynamics through their influence on bathymetry and dissipation. This study presents numerical simulations of this event with a focus on two main issues: first, how roughness variations affect tsunami run-up and whether different values of Manning’s roughness parameter, n, improve the simulated run-up compared to observations; and second, how depth variations in the shelf bathymetry with coral reefs control run-up and inundation on the island coastlines they shield. We find that no single value of n provides a uniformly good match to all observations; and we find substantial bay-to-bay variations in the impact of varying n. The results suggest that there are aspects of tsunami wave dissipation which are not captured by a simplified drag formulation used in shallow-water waves model. The study also suggests that the primary impact of removing the near-shore bathymetry in coral reef environment is to reduce run-up, from which we conclude that, at least in this setting, the impact of the near-shore bathymetry is to increase run-up and inundation.

The distribution and morphological characteristics of the shelves around Salina Island have been analyzed and integrated with observations from onshore geological field studies in order to improve knowledge about its evolution, and to demonstrate how shelf width/depth can be used as proxies for reconstructing the development of the volcanic edifice. Insular shelves form essentially through marine erosion of volcanic centres during stages of reduced or inactive volcanism, and are representative of their original extension. Shelves having larger widths (commonly > 1000 m) and deeper edges (over 125 m depth) experienced wave erosion during successive cycles of sea-level fluctuations and subsidence after their formation, thus being indicative of a relatively older age of the eroded volcanic centres. Accordingly, we document offshore Salina the occurrence of presently submerged and largely dismantled volcanic centres (namely Pizzo Capo North and Fossa delle Felci South) predating the oldest subaerial products exposed on the adjacent coastal sectors. These offshore centres have subsided after their erosion and are no more documented on land. Furthermore, the finding of the largest and deepest shelf around the subaerial remnants of Pizzo di Corvo volcanic edifice allows relating it to an earlier stage of evolution of Salina, shedding light on contradictory radiometric ages on land. Narrower shelves (commonly < 1000 m) indicate a lower evolutionary maturity with respect to the larger ones; they are, in fact, formed along the sectors of the island where younger volcanic products are exposed, such as to the north and south of Monte dei Porri. The depths of the shelf edges, mostly at - 110 m (in the areas not affected by later mass-wasting), suggest that these coastal sectors were relatively stable or even slightly uplifted after erosion during Last Glacial Maximum. Moreover, several interacting factors (such as lithology of volcanic products, fetch and exposure to prevailing storms, degree of submarine erosion, relative sea level changes) have been taken into account to explain the morphological setting of the different shelf and coastal sectors of Salina. On the whole, our results show the importance of integrated field and marine studies to unravel the geological evolution of insular volcanoes and to obtain inferences on their vertical mobility.

The southwest Pacific is host to a number of mineralization styles, including numerous world-class porphyry Cu-Au and epithermal Au-Ag deposits (Cooke et al., 2005; Garwin et al., 2005). The majority of the giant porphyry and epithermal Au and Cu deposits were formed within a series of middle to late Cenozoic (25–1 Ma) arcs (Garwin et al., 2005; Maryono et al., 2018). These arcs form a complex boundary between the Eurasian, Pacific, and Indian-Australian tectonic plates, stretching from Japan in the northeast and Myanmar in the northwest, through the Philippines, Indonesia, New Guinea, and the volcanic island chains of the Solomon Islands, New Hebrides (Vanuatu), and Fiji (Fig. 1).

Studies on the mobility of past populations are useful in the interpretation of trade and lifestyle. Preservation of ancient paths is uncommon. In Tenerife, a volcanic island of the Canary ...

We present a review of groundwater studies over the past 50 years (1968–2017) in Korea. With economic and agricultural growth, water demand has been expanding, and groundwater development is gradually increasing. Initially, groundwater studies were largely focused on using pumping and slug tests to understand aquifers in Korea. However, the interest has expanded to groundwater monitoring and data analyses, as many national and local networks for monitoring groundwater quantity and quality have been implemented. Frequent severe droughts in recent decades have led to research on the design and pilot tests for managed aquifer recharge, especially on the volcanic island of Jeju and agricultural areas. As groundwater development and its use has increased, groundwater contamination is becoming a public grievance. Thus, effective investigation of contaminated groundwater and its efficient remediation are big issues in the Research and Development (R & D) sector. The recent Gyeongju earthquake posed an additional challenge for Korean groundwater scientists to develop a method to predict earthquakes using groundwater monitoring. Furthermore, changes in precipitation patterns caused by the changing climate aggravate groundwater recharge conditions. The country has seen many academic and technical achievements in groundwater science, but many issues remain to be resolved in the near future.

International audience; The reconstruction of volcanic landforms is an effective way to assess the construction history and growth rates of volcanic structures and is a useful tool to estimate erosion rates. We propose a simple geometrical approach to reveal the location of the long-term eruption centers and the general shape of eroded volcanoes within the altitudinal range of the input data. This DEM-based approach consists of finding the radial topographic profile of an eroded volcanic landform from its remaining surfaces, by coupling two independent and simple mathematical methods (linear regression and Spearman rank correlation). Here we demonstrate that this simple approach is suitable for circular to elliptical (up to an ellipticity of 0.5) and to some extent for asymmetrical volcanoes, and we apply it to Réunion Island. Our results confirm previous conclusions from geological observations and data requiring more complex instrumentation. We confirm that the center of long-term volcanic activity of Piton des Neiges remained stable for the past 1.4 Myr while Piton de la Fournaise has been migrating eastward for~300 kyr. Our approach also reveals that Piton des Neiges is the dominant volcano in Réunion and that Piton de la Fournaise is a smaller edifice built on its edge. Moreover, despite the contribution of two other volcanoes in the construction of Réunion, we suggest that the Piton des Neiges has rapidly become the main structure of the whole island and has subsumed the previous volcanic centers. Finally, we use our approach to model the magmatic activity of Piton des Neiges, and suggest a deceleration of its magma emission rate since 2Myrs.

This article presents the characteristics of the small islands of Tidore and Hiri, which are vulnerable to the dangers of volcanic eruptions in Indonesia. The physical condition of the area is very important for carrying out a sustainable disaster risk reduction analysis; therefore, climate and topographic data are important to know. The limited availability of data in the study area causes climate data to be obtained from NASA’s Earth Science Data Systems (ESDS) and regional topographical presentation of Indonesia’s national DEM data. The results show that in the period 2004 to 2014, the temperature in the study area ranged from 292 K to 309 K. The islands of Tidore and Hiri have monthly precipitation between 50 mm to 500 mm.