The long-legged flies (Diptera: Dolichopodidae) from Kurile Islands, with description of a new species of the genus Sciapus Zeller, 1842

An annotated list of dolichopodid species recorded from Kurile Archipelago (Russia) is given for the first time. Sciapus basarukini sp. n. from Kunashir Island is described and illustrated. New records for 26 species, including 8 species new for the Kurile Islands, are presented. Long-legged flies are recorded for the first time from the Anuchina, Tanfilyeva, Polonskogo, Urup, Chirpoy, Brat-Chirpoyev, Simushir, Ushishir, Matua, Raikoke, Paramushir, Kharimkotan, Makanrushi, Atlasov, and Onekotan islands. Two species are excluded from the fauna of Kurils. In total, 54 species are recorded from the Kurile Archipelago that appa¬rently makes up 50–60% of the actual dolichopodid fauna in this region. The trends discovered on the Kurile Islands for plant species, i.e. the landscape diversity and the number of plant species increase from small to large islands, and decrease from southern islands northward, are generally supported by the case of flies of the family Dolichopodidae.

Fumarolic-like activity on carbonaceous chondrite parent body

Comparative planetology studies are key for understanding the main processes driving planetary formation and evolution. None have been yet applied to pristine asteroids formed in the solar protoplanetary disk, mainly because of their comminution during their 4.5-billion-year collisional lifetime. From remarkable textural, mineralogical, chemical, and thermodynamic similarities, we show that the high-temperature Kudryavy volcano fumarolic environment from Kurile Islands is a likely proxy of the Fe-alkali-halogen metasomatism on the CV and CO carbonaceous chondrite parent bodies. Ca-Fe–rich and Na-Al-Cl–rich secondary silicates in CV and CO chondrites are, thus, inferred to be fumarolic-like incrustations that precipitate from hot and reduced hydrothermal vapors after interactions with the wallrocks during buoyancy-driven Darcy flow percolation. These vapors may originate from the progressive heating and devolatilization of a chondritic protolith on their parent body or are remnant of the cooling of residual local nebular gases at the time of their primary planetesimal accretion.

Atmospheric mercury (Hg(0)) concentrations and Hg(0) fluxes in the Sea of Japan and the Okhotsk Sea in fall 2019

<p>Continuous measurements of gaseous elemental mercury (Hg(0)) in the marine boundary layer (MBL) and Hg(0) fluxes were conducted in the Sea of Japan and the Sea of Okhotsk from September 7 to October 17, 2019. All Hg(0) measurements were carried out using two RA-915M mercury analysers (Lumex LLC, Russia). Hg(0) concentrations in the air were measured at two levels (about 2 m and 20 m above the sea surface) with a time resolution of 30 minutes. Hg(0) fluxes were measured at five sample stations using a dynamic flux chamber.</p><p>During the cruise Hg(0) concentrations varied in the range from 0,47 ng/m<sup>3</sup> to 1,55 ng/m<sup>3</sup>, and from 0,31 ng/m<sup>3</sup> to 2,71 ng/m<sup>3</sup> with medians of 0,92 ng/m<sup>3</sup> for 2 m and 20 m, respectively. Atmospheric Hg(0) concentrations in measurements sites were strongly depended on the regions from where air masses came to the study areas. As a result of the Concentration Weighted Trajectory (CWT) analysis we established 2 regions that influenced the Hg(0) concentrations during the cruise: the Northeast China with the Yellow Sea region and the Kurile Islands sector of the Pacific Ocean. The arrival of air masses from China and the Yellow Sea region caused an increase in Hg(0) concentrations in the air in the Sea of Japan and the Sea of Okhotsk. Elevated concentrations were also observed In the Sea of Okhotsk during the periods air masses came from the Kurile Islands sector of the Pacific Ocean.</p><p>Hg(0) fluxes were measured at 3 stations in the Sea of Japan and at 2 stations in the Sea of Okhotsk. The values ranged from 0,57 ng/m<sup>2</sup>/h to 1,55 ng/m<sup>2</sup>/h, with median value of 1,32 ng/m<sup>2</sup>/h. A positive relationships between Hg(0) flux and air and water temperature were observed.</p><p>This work was supported by the Russian Science Foundation (RSF) (Project № 19-77-10011) and by the National Natural Science Foundation of China (Projects №: 41876065, 41420104005, U1606401) and National Program on Global Change and Air-Sea Interaction (Project № GASI-GEOGE-04).</p>

Vulcanian/hydrothermal eruptions of Ebeko volcano, Kurile Islands

<p>Ebeko is a small (1156 m a.s.l) andesitic volcano located in the northern part of Paramushir island of Kurile Island Arc. It is not well studied but in fact represents the most active volcano of the Kuriles  with > 10 eruptions recorded in the 20th century.  All historical eruptions of the volcano had similar style. They were purely explosive, mild (VEI 1 – 2) series of frequent short-lived outbursts of ash and bombs with eruptive clouds up to 3 km high. Some of the outbursts were more extended in time (lasted minutes-hours) and produced mostly fine ash. Common explosions occurred in the summit area of the volcano which characterized by strong hydrothermal activity and multiple fumaroles depositing sulfur. Each eruption produced broad, shallow craters surrounded by low rims of the ejected material. Commonly the craters are later occupied by shallow lakes.</p><p> In 2019 we realized a field work to investigate the most recent eruptive activity of Ebeko that commenced in 2016.  We installed seismometers, monitoring cameras and recorded the terrain using unmanned aerial systems (UAS) together with optical and infrared cameras. The drone data shows dimensions and structures of the newly forming crater and shows deposition of erupted materials. Ejected material was probed and analysed. It is represented by ash and bread crust bombs composed of moderately vesicular two pyroxene andesite with glassy crusts. We found evidence for recycling and rewelding of ash shown by the clastic domains, which are enclosed / mantled by coherent lava. The eruptions of Ebeko volcano were in part phreatic (hydrothermal) and in part magmatic / phreatomagmatic (vulcanian in a broad sense). Mechanism of this (and probably of some other eruptions) can be explained by shallow intrusions of small batches of strongly crystallized andesitic magma into water-saturated hydrothermally altered rocks composing the volcano summit. We suggest a model of the Ebeko eruptions, where new batches of fresh magma incorporate and amalgamate previously erupted fresh material.</p>

Water in parental basaltic magmasof the Menshiy Brat volcano (Iturup Island, Kurile islands)

The paper presents study of the liquidus assemblage of olivine and spinel in high-magnesian basalts (MgO up to 10 mas. %) of the Menshiy Brat volcano (Iturup Island). It was possible to reconstruct the water content and evolution of volatile components in the primary parental magmas that took part in the formation of the Medvezhya Caldera, Iturup Islands. It is shown that the initial water content in the primary melts could reach 5 mas. % with oxygen fugacity corresponding to oxygen buffer NNO + 0.4 log. units. The evolution of magmas involved continuous degassing while magma rises to the surface. The water-rich fluid, which is constantly separated by evolving magma, could play a significant role in the formation of large siliceous magma chambers, which participated in catastrophic caldera eruptions.