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The Kula Field is the youngest volcanic center in western Türkiye, and consists of various well-preserved volcanic products. Although many geological studies have been conducted in the region, geophysical anomalies have not been studied in detail. Therefore, we analyzed the aeromagnetic anomalies of these volcanic products by performing inversion studies with a recently proposed global optimizer. This study is the first attempt to use success-history-based adaptive differential evolution algorithm (SHADE) for inverting magnetic anomalies. To reduce the computational cost, we introduced the E-SHADE scheme by incorporating an exponential population reduction strategy into the optimizer. A synthetic anomaly study revealed the mathematical nature of the handled inverse problem. Some pre- and post-inversion analyses showed the efficiency of the proposed algorithm. Additionally, we observed that the E-SHADE algorithm produced better results than a commonly used derivative-based local optimizer. Nine profile data sets including magnetic anomalies of some volcanic cones in the Kula region were inverted. It was determined that the basaltic intrusions that allow the mantle material to uplift rapidly are not very deep in the subsurface. Therefore, it is possible that the three-phased volcanism may become active again and generate new alkaline basaltic lava flows in a new phase through these shallow dykes.

We obtain new images of the 3D resistivity structure of the Wudalianchi volcanic field (WVF). No low‐resistivity structure is found beneath Laoheishan and Huoshaoshan volcanoes in the WVF, which challenges the hypothesis of one or more magma reservoirs in the upper crust of this region. We observe a low‐resistivity body beneath Weishan volcano; however, estimated magma emplacement rates conflict with the observed volume of that body. Due to the relatively low geothermal gradient and surface heat flow in the area, magma would cool rapidly and could not be sustained for a long time unless new magma was regularly introduced into the system, but our observations do not support this scenario. We suggest that the magma in the WVF mainly originates from the mantle or the base of the crust with little crustal residence, and that the low‐resistivity body in the upper crust is likely due to saline aqueous free fluids. Plain Language Summary The origin of magma, whether it is derived directly from the deep mantle or has previously resided in the crust, plays a crucial role in determining volcanic eruption mechanisms. The presence of a magma reservoir in the shallow crust often signifies an increased risk of volcanic eruptions. The Wudalianchi volcanic field (WVF) is situated in northeastern China. Earlier research suggested the existence of a magma reservoir beneath the Weishan volcano within the WVF. However, our study reveals an absence of magma reservoirs beneath the more recently erupted Laoheishan and Huoshaoshan volcanoes. This raises the question of why a magma reservoir is present beneath Weishan, which experienced an eruption 0.5 Ma ago, rather than beneath Laoheshan and Huoshaoshan, which erupted a mere 300 years ago. Furthermore, the WVF is characterized by an extremely low geothermal gradient, causing magma in the shallow crust to lose substantial heat and cool rapidly, unless replenished by a continuous influx of high‐temperature magma. Nevertheless, the volume of magma injection inferred from the low‐resistivity body beneath Weishan is inconsistent with numerical simulation results. Consequently, we suggest that the low‐resistivity body beneath Weishan volcano is instead a structure containing saline aqueous free fluids, not magma. Key Points Electrical structure of the Wudalianchi volcanic field (WVF) is imaged Subsurface beneath Laoheishan and Huoshaoshan volcanoes is highly resistive Low‐resistivity body beneath Weishan volcano is due to saline aqueous free fluids

Antimilos volcano in the South Aegean Volcanic Arc, Greece, comprises an andesite–dacite suite that follows a distinct evolutionary path than the main edifice of the Milos volcanic field, despite their proximity. Petrographic and geochemical analyses reveal that basaltic andesite to low-Si dacite lavas have similar phenocryst assemblages that indicate crystallization from hot, relatively dry magmas in an upper crustal storage region. Rare antecrystic high-Mg# clinopyroxene cores with low Y, low Dy, and high Sr contents record the cryptic involvement of amphibole, a phase nominally absent from the erupted products, in the deeper parts of the plumbing system. Low temperature antecrysts with textures recording various degrees of disequilibrium suggest a protracted history of interaction between the upper crustal reservoir and deeper mafic melts, forming mobile hybrid magmas that consequently erupt as highly mingled, crystal-rich lava domes. Antimilos magmas seem to have escaped recharge filtering in the upper crust and prolonged stalling, which is the process that is probably responsible for the paucity of mafic eruptions in the rest of the Milos volcanic system. Large extensional structures offshore of Antimilos promote rapid ascent of mafic melts, inhibiting prolonged stalling and interaction with the arc crust. This model highlights the dominant role of the regional stress field in generating petrologically distinct suites in the marginal parts of some volcanic fields.

The Changbaishan volcanic field, which includes the Tianchi and Wangtian'e volcanoes in China and the Namphothe volcano in North Korea, is one of the most complex and hazardous volcanic regions on Earth due to its tectonic setting and explosive Holocene activity. Although the magmatic structure beneath the Tianchi volcano has been widely studied, the subsurface systems beneath the Wangtian'e and Namphothe volcanoes remain unknown. Using receiver function data from a dense seismic array, we present the first high‐resolution images of crustal thickness and Vp/Vs structure across the Tianchi and Wangtian'e volcanic fields. H−κ $H-\\kappa $ stacking shows that the Tianchi volcano is underlain by a thick crust with high Vp/Vs, while the Wangtian'e volcano has normal crustal thickness but similarly elevated Vp/Vs. Common Conversion Point imaging reveals strong negative phases at depths of 5–10 km beneath both volcanoes, marking the likely tops of major crustal magma chambers. Ambient noise tomography, derived from the densest broadband data set collected in this region, also detects pronounced low‐velocity zones at similar depths. These results indicate that the two volcanoes form an interconnected magmatic system: mantle‐derived melts pool near the Moho beneath the Tianchi volcano and then migrate laterally to supply separate magma reservoirs beneath the Tianchi and Wangtian'e volcanoes. Notably, we identify partial melt beneath the Wangtian'e, a volcano long regarded as dormant or extinct, underscoring the need for continued monitoring and further geophysical studies of the entire Changbaishan volcanic complex.

A volcanological map of the active Ischia volcanic field that includes Vivara Island is presented. The volcanological map is at the 1:10,000 scale and is based on 1:5000 field mapping, geological CAR.G data, and new volcanological studies. Geological data are represented on the three-dimensional orographic background digital terrain model of the inland and offshore areas of the volcanic field. This allows a better visualization of the main morphological, volcanic, and geological structures. Six phases were identified on the basis of volcanotectonic events; the 110 volcanic units were arranged following these evolutive phases, and a volcanosedimentary apron unit was introduced. This volcanological map enables visualization of the volcanic evolution of the Ischia volcanic field and could be useful for the evaluation of volcano-related hazards in the area.

The Zacapu lacustrine basin is located in the north-central part of the Michoacán-Guanajuato volcanic field (MGVF), which constitutes the west-central segment of the Trans-Mexican Volcanic Belt. Geological mapping of a 395 km2 quadrangle encompassing the western margin of the basin, 40Ar/39Ar and 14C radiometric dating, whole-rock chemical and petrographic analyses of volcanic products provide information on the stratigraphy, erupted volumes, age, and composition of the volcanoes. Although volcanism in the MGVF initiated since at least 5 Ma ago, rocks in the western Zacapu lacustrine basin are all younger than ~ 2.1 Ma. A total of 47 volcanoes were identified and include 19 viscous lava flows (~ 40 vol.%), 17 scoria cones with associated lava flows (~ 36 vol.%), seven lava shields (~ 15 vol.%), three domes (~ 6 vol.%), and one maar (~ 2 vol.%). Erupted products are dominantly andesites with 42 km3 (~ 86 vol.%) followed by 4 km3 of dacite (~ 8 vol.%), 1.4 km3 of basaltic trachy-andesite (~ 3 vol.%), 1 km3 of basaltic andesite (~ 2 vol.%), and 0.14 km3 of rhyolite (~ 0.3 vol.%). Eruptive centers are commonly aligned ENE-WSW following the direction of the regional Cuitzeo Fault System. Over time, the high frequency of eruptions and consequent accumulation of lavas and pyroclastic materials pushed the lake’s shore stepwise toward the southeast. Eruptions appear to have clustered through time. One cluster occurred during the Late Pleistocene between ~ 27,000 and ~ 21,300 BC when four volcanoes erupted. A second cluster formed during the Late Holocene, between ~ 1500 BC and ~ AD 900, when four closely spaced monogenetic vents erupted forming thick viscous ‘a’a to blocky flows on the margin of the lacustrine flats. For still poorly understood reasons, these apparently inhospitable lava flows were attractive to human settlement and eventually became one of the most densely populated heartlands of the pre-Hispanic Tarascan civilization. With an average eruption recurrence interval of ~ 900 years during the Late Holocene the western Zacapu lacustrine basin is one of the most active areas in the MGVF and should hence be of focal interest for regional volcanic risk evaluations.

Deep low‐frequency earthquakes (DLFE) are observed beneath volcanoes worldwide but are limited to island arc volcanoes, hotspot volcanoes, and rift zones. Here we show DLFEs in the Tengchong Volcano Field, southeast Tibet, located ∼300 km from the Indo‐Burma volcanic arc, by analyzing a 12‐year continuous seismic data set. The earthquakes were at a depth of ∼12 km, near the sidewall of the magma body detected by the magnetotelluric survey. The features of isotropic focal mechanism, episodic occurrence, and possible non‐power‐law scaling, with no detectable geodetic deformation, as well as the petrological signatures of the Holocene eruption product, suggest that the earthquakes were likely associated with the weak intermittent magma flows near the magma body. This finding may demonstrate the existence of unsteady magmatic processes in the margin of the Indo‐Eurasia collision zone, which could indicate unneglectable volcanic hazards, underestimated geothermal resources, and mineralization processes in similar regions. Plain Language Summary Magmatic systems in the subduction arc, rift zone, and hotspot region are often active when magma stalls in the crust, indicative of unsteady magma dynamics and potential hazards. Holocene eruptions, present‐day structure anomaly, and geochemical signatures exist in some intra‐continent volcanos far away from the well‐predicted regions by plate tectonics. However, the magmatic systems there are thought to be relatively inactive. In this report, we show the first evidence of deep low‐frequency earthquakes occurring in the continental land on the edge of the Tibet Plateau, without any of the arc, hotspot, and rift volcanism involved. The observations' systematic characterization indicates weak but unsteady fluid flow currently occurring in this region. This finding demonstrates an unexpected behavior of the magmatic system in the continental collision zone, which may be underpredicted by the classic theory of plate tectonics on volcanism. Key Points We report the discovery of deep low‐frequency earthquakes in the margin of the Tibet Plateau Deep origin, isotropic mechanism, low occurrence, and non‐power‐law scaling of the earthquakes are likely related to an unsteady fluid flow Seismic, petrological, and geochemical observations suggest the existence of juvenile magma flow beneath the Tengchong Volcanic Field

The Pleiades Volcanic Field is made up of some 20 monogenetic, partly overlapping scoria and spatter cones, erupted in the last 900 ka, cropping out from the ice close to the head of the Mariner Glacier in northern Victoria Land, Antarctica. Erupted products vary from hawaiite to trachyte, defining a complete mild Na‐alkaline differentiation trend. Mafic samples are characterized by multi‐elemental patterns typical of OIB magmas, moderately low 87Sr/86Sr (0.7037) and high 143Nd/144Nd (0.51284), with a clear within‐plate affinity, indicating a subcontinental lithospheric source. With increasing SiO2, 87Sr/86Sr ratios increase up to 0.7052 and 143Nd/144Nd decrease to 0.51277, supporting the hypothesis of open‐system evolution, with significant crustal assimilation during fractional crystallization. The erupted volume of most evolved products (∼7 km3), according to fractionation models, suggests that primitive magmas should have been more than 10 times larger, indicating the occurrence of a large magma plumbing system, unexpected for a volcanic field of monogenetic scoria cones. The occurrence of a complete fractionation trend with large magma chambers and large assimilation rate is unusual, if not unique, among the alkali basaltic volcanic fields and it is matched by a climax of activity during the last glacial maximum (30 ka), as indicated by new 40Ar‐39Ar ages (30 ± 3 ka and 25 ± 2 ka) for samples from the two most prominent edifices. Therefore, we hypothesize a role of a thick ice cap in suppressing eruptions and ultimately leading to prolonged magma residence time in the subsurface, favoring significant fractionation coupled with unusual high rates of crustal assimilation. Plain Language Summary The Pleiades volcanic field is made up of some 20 monogenetic scoria and spatter cones, which erupted in the last 900 ka close to the head of the Mariner Glacier in northern Victoria Land, Antarctica. The erupted products are very unusual for alkali basaltic volcanism: indeed, whereas few samples show clear within‐plate subcontinental lithospheric characteristics and were directly derived from the mantle source, most of the products formed after extensive fractional crystallization matched by significant crustal assimilation, implying that primitive magma volumes are 10 times larger than outcropping products in an unusually large magma plumbing system. These peculiar features coincided with a climax of activity during the last glacial maximum (30–25 ka). Therefore, we speculate that a thick ice cap favored high rates of crystal fractionation coupled with crustal assimilation and was responsible for increasing magma residence times in chambers at crustal depths and suppressing the eruptive potential of magmas. Key Points The Pleiades complex (NVL, Antarctica) is made up of some 20 monogenetic cones aged 900–0 ka, defining a complete Na‐alkaline trend Fractionation models show much larger volumes of primitive magmas, indicating the occurrence of an unusually large magma plumbing system A climax of activity occurred during the last glacial maximum (30 ka). Thickness variation of the ice cap may have influenced volcanic activity

Five tephra layers named BRH1 to 5 were sampled in an ice cliff located on the north-eastern flank of Mount Melbourne (northern Victoria Land, Antarctica). The texture, componentry, mineralogy, and major and trace element compositions of glass shards have been used to characterize these layers. These properties suggest that they are primary fall deposits produced from discrete eruptions that experienced varying degrees of magma/water interaction. The major and trace element glass shard analyses on single glass shards indicate that Mount Melbourne Volcanic Field is the source of these tephra layers and the geochemical diversity highlights that the eruptions were fed by compositionally diverse melts that are interpreted to be from a complex magma system with a mafic melt remobilizing more evolved trachy-andesitic to trachytic magma pockets. Geochemical compositions, along with textural and mineralogical data, have allowed correlations between two of the englacial tephra and distal cryptotephra from Mount Melbourne, recovered within a marine sediment core in the Edisto Inlet (~ 280 km northeast of Mount Melbourne), and constrain the age of these englacial tephra layers to between the third and the fourth century CE. This work provides new evidence of the intense historical explosive activity of the Mount Melbourne Volcanic Field and better constrains the rates of volcanism in northern Victoria Land. These data grant new clues on the eruptive dynamics and tephra dispersal, and considerably expand the geochemical (major and trace elements) dataset available for the Mount Melbourne Volcanic Field. In the future, this will facilitate the precise identification of tephra layers from this volcanic source and will help define the temporal and spatial correlation between Antarctic records using tephra layers. Finally, this work also yields new valuable time-stratigraphic marker horizons for future dating, synchronization, and correlations of different palaeoenvironmental and palaeoclimatic records across large regions of Antarctica.

Morphometric studies of scoria cones have a long history in research. Their geometry and shape are believed to be related to evolution by erosion after their formation, and hence the morphometric parameters are supposed to be related with age. We analysed 501 scoria cones of four volcanic fields: San Francisco Volcanic Field (Arizona, USA), Chaîne des Puys (France), Sierra Chichinautzin (Mexico), and Kula Volcanic Field (Turkey). All morphometric parameters (cone height, cone width, crater width, slope angles, ellipticity) were derived using DTMs. As new parameters, we calculated Polar Coordinate Transformed maps, Spatial Elliptical Fourier Descriptors to study the asymmetries. The age groups of the four volcanic fields were created and their slope distributions were analysed. The age groups of individual volcanic fields show a statistically significant decreasing tendency of slope angles tested by Mann–Whitney tests. By mixing the age groups of the volcanic fields and sorting them by age interval, we can also observe a general, statistically significant decrease. The interquartile ranges of the distributions also tend to decrease with time. These observations support the hypothesis that whereas the geometry of individual scoria cones differs initially (just after formation), general trends may exist for their morphological evolution with time in the various volcanic fields.