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Kilauea Volcano's 2018 lower East Rift Zone (LERZ) eruption produced exceptionally high lava effusion rates and record-setting SO2 emissions. The eruption involved a diverse range of magmas, including primitive basalts sourced from Kilauea's summit reservoirs. We analyzed LERZ matrix glasses, melt inclusions, and host minerals to identify melt volatile contents and magma storage depths. The LERZ glasses and melt inclusions span nearly the entire compositional range previously recognized at Kilauea. Melt inclusions in Fo(86-89) olivine from the main eruptive vent (fissure 8) underwent 70-170 degrees C cooling during transport in LERZ carrier melts, causing extensive post-entrapment crystallization and sulfide precipitation. Many of these melt inclusions have low sulfur (400-900 ppm) even after correction for sulfide formation. CO2 and H2O vapor saturation pressures indicate shallow melt inclusion trapping depths (1-5 km), consistent with formation within Kilauea's Halema'uma'u and South Caldera reservoirs. Many of these inclusions also have degassed delta S-34 values (1.5 to -0.5%). Collectively, these results indicate that some primitive melts experienced near-surface degassing before being trapped into melt inclusions. We propose that decades-to-centuries of repeated lava lake activity and lava drain-back during eruptions (e.g., 1959 Kilauea Iki) recycled substantial volumes of degassed magma into Kilauea's shallow reservoir system. Degassing and magma recycling from the 2008-2018 Halema'uma'u lava lake likely reduced the volatile contents of LERZ fissure 8 magmas, resulting in lower fountain heights compared to many prior Kilauea eruptions. The eruption's extreme SO2 emissions were due to high lava effusion rates rather than particularly volatile-rich melts. U.S. Geological Survey (USGS) Volcano Science Center; Hawaiian Volcano Observatory (HVO); University of Hawaii-Hilo; HVO volunteer program; Department of Earth Sciences at the University of Oregon; Mineralogical Society of America; Geological Society of America; Mazamas student research grant program; National Science Foundation (NSF) Graduate Research Fellowship ProgramNational Science Foundation (NSF); NSF Graduate Research Internship Program (GRIP) Published version The authors would like to thank Matthew Loewen, Nicole Metrich, and Matt Patrick for constructive input that significantly improved this manuscript. The authors also thank the U.S. Geological Survey (USGS) Volcano Science Center, Hawaiian Volcano Observatory (HVO), University of Hawaii-Hilo, partner agencies, and the residents of Hawaii for support, field access, data sharing, and for their great care in documenting and responding to the 2018 LERZ eruption crisis. AHL thanks Tina Neal and the HVO volunteer program for support, Mike Zoeller for map assistance, and Carolyn Parcheta for collecting and sharing samples. Geochemical analyses were conducted with the help of John Donovan and Julie Chouinard (EPMA), and Brian Monteleone and Glenn Gaetani (SIMS and MI rehomogenization). AHL thanks Michelle Muth and Madison Myers for discussions on methodology and melt inclusion interpretation. AHL acknowledges funding support from Department of Earth Sciences at the University of Oregon, the Mineralogical Society of America, the Geological Society of America, the Mazamas student research grant program, the National Science Foundation (NSF) Graduate Research Fellowship Program, and the NSF Graduate Research Internship Program (GRIP). Coordination of GRIP at the USGS is through the Youth and Education in Science programs within the Office of Science Quality and Integrity. Public domain – authored by a U.S. government employee

We characterized volatile emissions based upon diffuse soil degassing measurements and fumarolic gas chemistry at Crater Hills, a thermally-altered area adjoining the Sour Creek resurgent dome that is located within the Yellowstone Caldera. The objective of this study was to investigate the source and flux of CO2 and H2S gases to improve our understanding of both the total emissions and origin of the spatial distribution. The total emission of CO2 estimated using the sequential Gaussian simulation method (sGs) was 66 to 109 t day−1 with 95% confidence, which is an underestimation due to the: (1) inability to measure a high flux area on a steep slope, and (2) absence of measurements from fumarole and hot pool emissions. Based on gas chemistry data obtained for a fumarole at Crater Hills in 2007, the proportion of CO2 calculated to be derived from magma would be at least 38%, but could be as high as 50%. The spatial distribution of prominent geothermal features with the highest gas flux are broadly consistent with the regional fault pattern and, therefore, likely reflect the pattern of blind faults and/or fractures covered by overlying alluvium. The estimated emission of H2S was 0.39 t day−1, based on the linear correlation between H2S and CO2. The heat output was also estimated to be ~35 MW with an average heat flux of ~100 W m−2 based upon CO2-H2O-heat relations.

Connecting caldera collapse The Kīlauea Volcano on the island of Hawai‘i erupted for 3 months in 2018. Neal et al. present a summary of the eruption sequence along with a variety of geophysical observations collected by the Hawaiian Volcano Observatory. The cyclic inflation, deflation, and eventual collapse of the summit was tied to lava eruption from lower East Rift Zone fissures. A total volume of 0.8 cubic kilometers of magma erupted, roughly the equivalent of 320,000 swimming pools, which matched the change in volume at the summit. Science , this issue p. 367

Starting on 3 May 2018, a series of eruptive fissures opened in Kīlauea Volcano’s lower East Rift Zone (LERZ). Over the course of the next 3 months, intense degassing accompanied lava effusion from these fissures. Here, we report on ground-based observations of the gas emissions associated with Kīlauea’s 2018 eruption. Visual observations combined with radiative transfer modeling show that ultraviolet light could not efficiently penetrate the gas and aerosol plume in the LERZ, complicating SO2 measurements by differential optical absorption spectroscopy (DOAS). By applying a statistical method that integrates a radiative transfer model with the DOAS retrievals, we were able to calculate sulfur dioxide (SO2) emission rates along with estimates of their uncertainty. We find that sustained SO2 emissions were highest in June and early July, when approximately 200 kt SO2 were emitted daily. At the 68% confidence interval, we estimate that 7.1–13.6 Mt SO2 were released from the LERZ during the entire May to September eruptive episode. Scaling our results with in situ measurements of plume composition, we calculate that 11–21 Mt H2O and 1.5–2.8 Mt CO2 were also emitted. The gas and aerosol emissions caused hazardous conditions in areas proximal to the active vents, but plume dispersion modeling shows that the eruption also significantly impacted air quality hundreds of kilometers downwind. Combined with petrologic studies of the erupted lavas, our measurements indicate that 1.1–2.3 km3 dense-rock equivalent of lava were erupted from the LERZ, which is approximately twice the concomitant collapse volume of the volcano’s summit.

Bagana volcano, Papua New Guinea, is among Earth’s youngest and most active volcanoes. Bagana typically exhibits multi-year episodes of lava extrusion, interspersed with pause periods characterised by strong passive degassing. Based on satellite-based observations, Bagana is the third ranked global source of volcanic sulfur dioxide over the past 15 years. Recent work based on global correlations between volcanic gas composition and magma trace element chemistry has predicted that it may be the fifth ranked global volcanic deep carbon source. However, this indirect estimate of Bagana’s potential carbon budget has yet to be ground-truthed by in-situ sampling.We visited Bagana in September 2019 and made the first measurements of the chemical composition of the volcano’s summit gas plume. We placed a miniaturized MultiGAS sensor array on board an unoccupied aerial system (UAS, or drone) and flew the sensors through the plume. Our aircraft flew beyond visual line of sight, reaching the gas plume from around 7 km horizontal distance and 2 km altitude below the summit. Such long-range UAS flights offer immense potential for studying gas emissions from such steep, active or remote volcanoes.Our MultiGAS flights found relatively low concentrations of both sulfur dioxide and carbon dioxide in the Bagana plume. Moreover, we made coincident remote sensing measurements of sulfur dioxide emissions using ground- and UAS-based ultraviolet spectroscopy and calculated SO2 fluxes of only ~400 tonnes per day. These are an order of magnitude below the typical fluxes inferred from satellite observations. Combining MultiGAS plume composition (CO2/SO2 molar ratio, mean ~3.4) and SO2 fluxes allow us to estimate Bagana’s CO2 flux into the atmosphere as only ~1360 t/d.Our interpretation of these results is that the volcano is presently in a low state of activity. From satellite observations, we note the cessation of the most recent extrusive episode several weeks prior to our field campaign. The lack of the anticipated strong passive degassing often observed by spaceborne UV sensors is likely a result of “scrubbing” in the volcanic edifice, where rising gases interact with groundwater, resulting in dissolution of sulfur species into the groundwater and perhaps precipitation of sulfur-bearing minerals into edifice fractures. As the volcano moves towards a future extrusive episode, we might anticipate the gradual drying out of the hydrothermal system and a shift towards more truly magmatic gas compositions. Our results show that short campaign measurements may not provide data which are representative of a volcano’s longterm behaviour and we suggest that caution is needed in using such data to calculate or extrapolate regional and global volatile emissions inventories.

Throughout Eurasia, bride kidnapping continues to be a fairly common way to get married. The practice is becoming increasingly controversial. Some local actors argue the practice is a cultural trad...

Carbon dioxide emissions from active subaerial volcanoes represent 20–50% of the annual global volcanic CO2 flux (Barry et al., 2014). Passive degassing of carbon from the flanks of volcanoes, and the associated accumulation of dissolved inorganic carbon (DIC) within nearby groundwater, also represents a potentially important, yet poorly constrained flux of carbon to the surface (Werner et al., 2019). Here we investigate sources and sinks of DIC in groundwaters in the Lassen Peak region of California. Specifically, we report and interpret the relative abundance and isotopic composition of helium (3He, 4He) and carbon (12C, 13C, 14C) in 37 groundwater samples, from 24 distinct wells, collected between 20 and 60 km from Lassen Peak. Measured groundwater samples have air-corrected 3He/4He values between 0.19 and 7.44 RA (where RA = air 3He/4He = 1.39 × 10−6), all in excess of the radiogenic production value (~0.05 RA), indicating pervasive mantle-derived helium additions to the groundwater system in the Lassen Peak region. Stable carbon isotope ratios of DIC (δ13C) vary between −12.6 and − 27.7‰ (vs. VPDB). Measured groundwater DIC/3He values fall in the range of 2.2 × 1010 to 1.1 × 1012. Using helium and carbon isotope data, we explore several conceptual models to estimate surface carbon contributions and to differentiate between DIC derived from soil CO2 versus DIC derived from external (slab and mantle) carbon sources. Specifically, if we use 14C to identify soil-derived DIC (assuming decadal-to-centennial groundwater ages and a soil CO2 14C activity equal to that of the atmosphere), we calculate that a hypothetical external carbon source would have an apparent δ13C signature between −10.3 and − 59.3‰ (vs. Vienna Pee Dee Belemnite (VPDB)) and an apparent C/3He between 7.0 × 109 and 1.0 × 1012. These apparent δ13C and C/3He values are substantially isotopically lighter than and greater than canonical MORB values, respectively. We suggest that >95% of any external (non-soil-derived) DIC in groundwater must thus be non-mantle in origin (i.e., slab derived or assimilated organic carbon). We further investigate possible sources of external DIC to groundwater using two idealized conceptual approaches: a pure (unfractionated) source mixing model (after Sano and Marty, 1995) and a scenario that invokes fractionation due to calcite precipitation. Because the former model requires carbon contributions from an organic source component with unrealistically low δ13C (~ − 60‰), we suggest that the second scenario is more plausible. Importantly, however, we caution that all conceptual models are dependent on assumptions about initial 14C activity. Thus, we cannot rule out the possibility that the true fraction of non-surface-derived DIC in these samples is lower or negligible, despite the pervasive mantle-derived He isotope signatures throughout the region. Following the 14C approach to deconvolving sources of DIC, we determine that the maximum passive carbon flux could be up to ~2.2 × 106 kg/yr, which is lower than previous magmatic carbon flux estimates from the Lassen region ( Rose and Davisson, 1996 ). We find that the passive dissolved carbon flux could represent a maximum of ~4–18% of the total Lassen geothermal CO2 degassing flux (estimated to be ~3.5 × 107 kg/yr Rose and Davisson, 1996 ; Gerlach et al., 2008 ), which is still more than an order of magnitude smaller than soil gas CO2 flux estimates (7.3–11 × 107 kg/yr) for nearby volcanoes ( Sorey et al., 1998 ; Gerlach et al., 1999 ; Evans et al., 2002 ; Werner et al., 2014 ). We conclude that passive dissolved carbon fluxes should be combined with geothermal fluxes and soil gas fluxes to obtain a complete picture of volcanic carbon emissions globally. Our approach highlights the utility of measuring helium isotopes in concert with the full suite of noble gas abundances, tritium, δ13C and 14C, which when interpreted together can be used to better elucidate the various sources of DIC in groundwater.

This article explores issues of citizenship and belonging associated with post-Soviet Kazakhstan’s repatriation programme. Beginning in 1991, Kazakhstan financed the resettlement of over 944,000 di...

Mount Cleveland volcano (1730 m) is one of the most active volcanoes in the Aleutian arc, Alaska, but heightened activity is rarely accompanied by geophysical signals, which makes interpretation of the activity difficult. In this study, we combine volcanic gas emissions measured for the first time in August 2015 with longer-term measurements of thermal output and lava extrusion rates between 2011 and 2015 calculated from MODIS satellite data with the aim to develop a better understanding of the nature of volcanic activity at Mount Cleveland. Degassing measurements were made in the month following two explosive events (21 July and 7 August 2015) and during a period of new dome growth in the summit crater. SO2 emission rates ranged from 400 to 860 t d− 1 and CO2/SO2 ratios were

CO2 flux measurements are often used to monitor volcanic systems, understand the cause of volcanic unrest, and map sub-surface structures. Currently, such measurements are incomplete at Tarawera (New Zealand), which erupted with little warning in 1886 and produced a ∼17 km long fissure. We combine new soil CO2 flux and C isotope measurements of Tarawera with previous data from Rotomahana and Waimangu (regions also along the 1886 fissure) to fingerprint the CO2 source, understand the current pathways for degassing, quantify the CO2 released along the entire fissure, and provide a baseline survey. The total CO2 emissions from the fissure are 1227 t⋅d–1 (742–3398 t⋅d–1 90 % confidence interval), similar to other regions in the Taupō Volcanic Zone. The CO2 flux from Waimangu and Rotomahana is far higher than from Tarawera (>549 vs. ∼4 t⋅d–1 CO2), likely influenced by a shallow silicic body at depth and Okataina caldera rim faults increasing permeability at the southern end of the fissure. Highly localized regions of elevated CO2 flux occur along the fissure and are likely caused by cross-cutting faults that focus the flow. One of these areas occurs on Tarawera, which is emitting ∼1 t⋅d–1 CO2 with a δ13CO2 of −5.5 ± 0.5 ‰, and comparison with previous observations shows that activity is declining over time. This region highlights the spatial and temporal complexity of degassing pathways at volcanoes and that sub-surface structures exert a primary control on the magnitude of CO2 flux in comparison to the surface mechanism (i.e., CO2 released through the soil or lake surface). Published version

Volcanoes are the main pathway to the surface for volatiles that are stored within the Earth. Carbon dioxide (CO2) is of particular interest because of its potential for climate forcing. Understanding the balance of CO2 that is transferred from the Earth’s surface to the Earth’s interior, hinges on accurate quantification of the long-term emissions of volcanic CO2 to the atmosphere. Here we present an updated evaluation of the world’s volcanic CO2 emissions that takes advantage of recent improvements in satellite-based monitoring of sulfur dioxide, the establishment of ground-based networks for semi-continuous CO2-SO2 gas sensing and a new approach to estimate key volcanic gas parameters based on magma compositions. Our results reveal a global volcanic CO2 flux of 51.3 ± 5.7 Tg CO2/y (11.7 × 1011 mol CO2/y) for non-eruptive degassing and 1.8 ± 0.9 Tg/y for eruptive degassing during the period from 2005 to 2015. While lower than recent estimates, this global volcanic flux implies that a significant proportion of the surface-derived CO2 subducted into the Earth’s mantle is either stored below the arc crust, is efficiently consumed by microbial activity before entering the deeper parts of the subduction system, or becomes recycled into the deep mantle to potentially form diamonds.

Volcanoes are the main pathway to the surface for volatiles that are stored within the Earth. Carbon dioxide (CO2) is of particular interest because of its potential for climate forcing. Understanding the balance of CO2 that is transferred from the Earth’s surface to the Earth’s interior, hinges on accurate quantification of the long-term emissions of volcanic CO2 to the atmosphere. Here we present an updated evaluation of the world’s volcanic CO2 emissions that takes advantage of recent improvements in satellite-based monitoring of sulfur dioxide, the establishment of ground-based networks for semi-continuous CO2-SO2 gas sensing and a new approach to estimate key volcanic gas parameters based on magma compositions. Our results reveal a global volcanic CO2 flux of 51.3 ± 5.7 Tg CO2/y (11.7 × 1011 mol CO2/y) for non-eruptive degassing and 1.8 ± 0.9 Tg/y for eruptive degassing during the period from 2005 to 2015. While lower than recent estimates, this global volcanic flux implies that a significant proportion of the surface-derived CO2 subducted into the Earth’s mantle is either stored below the arc crust, is efficiently consumed by microbial activity before entering the deeper parts of the subduction system, or becomes recycled into the deep mantle to potentially form diamonds.

Cleveland and Tana are remote volcanoes located in the central Aleutian volcanic arc on the eastern end of the Islands of Four Mountains (IFM). The persistently active Mount Cleveland volcano, on the western side of Chuginadak Island, is surrounded by several closely spaced Quaternary volcanic centers including Carlisle, Herbert, Kagamil, Tana, and Uliaga, and numerous small satellite vents on Chiginadak between Cleveland and Tana. The Alaska Volcano Observatory (AVO) installed two permanent broadband seismometers on Chuginadak Island in 2014, and we operated a temporary broadband network focused on the western side of the island in 2015–2016. Collectively, these stations provided the first seismic observations of this frequently active volcano and the surrounding Holocene-aged volcanic vents. During the study period (July 2014–January 2019), eruptive activity at Cleveland was characterized by small explosions separated by periods of lava effusion that formed small domes in the volcano's summit crater. We characterize seismicity beneath Chuginadak Island through automated analysis of event waveform frequency content, development of a one-dimensional P-wave velocity model, calculation of earthquake hypocenters, magnitudes, focal mechanisms, and identification of earthquake families. This analysis reveals the full range of seismic event types expected in a highly active volcanic environment and includes Volcano-Tectonic (VT) earthquakes, Long-Period (LP) events, and explosion signals. LP events appear to cluster at shallow depth beneath the active crater of Mount Cleveland and almost all of the explosions occur without identifiable short-term (hours to days) seismic precursors. VT earthquakes beneath Mount Cleveland occur at depths of 2 to 8 km below sea level (BSL) and range in magnitude from −0.2 to 1.8. VT focal mechanisms have horizontal P-axes that align with the regional axis of maximum stress. These observations, and a relatively slow one-dimensional seismic velocity model, are consistent with a shallow body of magma that is fed through a deeper conduit system. The time-history of VT earthquakes and shallow LP events suggest their occurrence may track the transfer of magma and fluids from the mid-crust to the shallow portions of the conduit system and may provide a means to anticipate future explosions and periods of dome growth. VT hypocenters also extend ~7 km northeast of Cleveland's summit at depths of 5 to 10 km BSL, under a group of Holocene-aged vents between Mount Cleveland and Tana. These earthquakes have vertically-oriented P-axes and a greater percentage occur in families. These observations, combined with observations of vent orientation and morphology and gas flux, suggest the area between Cleveland and Tana represents a zone of complicated volcano-tectonic interaction, similar to calderas elsewhere in the Aleutian arc. The presence of a larger volcanic system in the eastern IFM could influence magmatism and account for the multiple closely spaced volcanic centers in this region.

One of the defining characteristics of globalization is the increased flow of migrants across international borders. Fluctuating migration flows in rural communities of the Global South have the potential to significantly contribute to or undermine the livelihoods of local residents. Households that choose not to migrate, that remain immobile, play a key role in sustaining rural communities. Migration studies in the Global South, however, have largely neglected these households. Utilizing questionnaire and life history interview data collected between 2006 and 2009, we examine immobility amongst the Kazakh ethnic minority population in rural Mongolia. Our findings challenge the dichotomous portrayal of immobile households as either ‘left behind’ or ‘embedded’ within their community, providing evidence that immobility decisions are both fluid and flexible and require more interrogation from scholars. Our findings help broaden the social and cultural context in which immobility studies are conducted...

Long period (LP) seismicity and very long period infrasound (iVLP) were recorded during continuous degassing from Mount Pagan, Mariana Islands, in July 2013 to January 2014. The frequency content of the LP and iVLP events and delay times between the two arrivals were remarkably stable and indicate nearly co-located sources. Using phase-weighted stacking over similar events to dampen noise, we find that the LP source centroid is located 60 m below and 180 m west of the summit vent. The moment tensor reveals a volumetric source modeled as resonance of a subhorizontal sill intersecting a dike. We model the seismoacoustic wavefields with a coupled earth-air 3-D finite difference code. The ratios of pressure to velocity measured at the infrasound arrays are an order of magnitude larger than the synthetic ratios, so the iVLP is not the result of LP energy transmitting into the atmosphere at its epicenter. Based on crater shape and dimensions determined by structure from motion, we model the iVLP as acoustic resonance of an exponential horn. The source of the continuous plume from gas analysis is shallow magmatic degassing, which repeatedly pressurized the dike-sill portion of the conduit over the 7 months of observation. Periodic gas release caused the geologically controlled sill to partially collapse and resonate, while venting of gas at the surface triggered resonance in the crater. LP degassing only accounts for ~12% of total degassing, indicating that most degassing is relatively aseismic and that multiple active pathways exist beneath the vent.

Magmatic hydrothermal systems are of increasing interest as a renewable energy source. Surface heat flux indicates system resource potential, and can be inferred from soil CO 2 flux measurements and fumarole gas chemistry. Here we compile and reanalyze results from previous CO 2 flux surveys worldwide to compare heat flux from a variety of magma-hydrothermal areas. We infer that availability of water to recharge magmatic hydrothermal systems is correlated with heat flux. Recharge availability is in turn governed by permeability, structure, lithology, rainfall, topography, and perhaps unsurprisingly, proximity to a large supply of water such as the ocean. The relationship between recharge and heat flux interpreted by this study is consistent with recent numerical modeling that relates hydrothermal system heat output to rainfall catchment area. This result highlights the importance of recharge as a consideration when evaluating hydrothermal systems for electricity generation, and the utility of CO 2 flux as a resource evaluation tool.

SO 2 camera measurements at Kīlauea Volcano, Hawaii, in May of 2010 captured two occurrences of lava lake rise and fall within the Halema'um'au Crater summit vent. During high lava stands we observed diminished SO 2 emission rates and decreased seismic tremor. Similar events at Kīlauea have been described as the result of sporadic degassing following gas accumulation beneath a mostly impermeable lava lake surface. Incorporation of SO 2 camera data into a multi-parameter dataset gives credence to the likelihood of shallow gas accumulation as the cause of these high stand events, with accumulated gas release upon lake-level drop compensating for the gas deficit reached during accumulation.

SO 2 camera systems allow rapid two-dimensional imaging of sulfur dioxide (SO 2 ) emitted from volcanic vents. Here, we describe the development of an SO 2 camera system specifically designed for semi-permanent field installation and continuous use. The integration of innovative but largely “off-the-shelf” components allowed us to assemble a robust and highly customizable instrument capable of continuous, long-term deployment at Kīlauea Volcano's summit Overlook Crater. Recorded imagery is telemetered to the USGS Hawaiian Volcano Observatory (HVO) where a novel automatic retrieval algorithm derives SO 2 column densities and emission rates in real-time. Imagery and corresponding emission rates displayed in the HVO operations center and on the internal observatory website provide HVO staff with useful information for assessing the volcano's current activity. The ever-growing archive of continuous imagery and high-resolution emission rates in combination with continuous data from other monitoring techniques provides insight into shallow volcanic processes occurring at the Overlook Crater. An exemplary dataset from September 2013 is discussed in which a variation in the efficiency of shallow circulation and convection, the processes that transport volatile-rich magma to the surface of the summit lava lake, appears to have caused two distinctly different phases of lake activity and degassing. This first successful deployment of an SO 2 camera for continuous, real-time volcano monitoring shows how this versatile technique might soon be adapted and applied to monitor SO 2 degassing at other volcanoes around the world.

Accompanying the dissolution of the USSR and the formation of new nation states in the 1990s, nearly half of Mongolian Kazakhs migrated from their adopted home of Mongolia to the imagined homeland of Kazakhstan. By 2000, a sizable percentage returned to Mongolia. In explaining their decisions to stay in or to return to Mongolia, the Kazakhs we interviewed cite several culturally specific factors. Place identities, as expressed through cultural elements of religiosity, kinship ties, and language versatility, tie Mongolian Kazakhs strongly to western Mongolia while meta-narratives about diaspora and homeland prescribe identity with Kazakhstan. Utilizing life history interviews, participant observation, and questionnaire data we argue that Mongolian Kazakhs actively employ narratives of their cultural history to re-create and re-establish place identities in Mongolia and ultimately re-imagine Mongolian-Kazakh community and identity. These recreated place identities have emerged among Mongolian-Kazakhs who chose to remain immobile or return migrated from the ‘homeland’ of Kazakhstan.

Beginning in 1992, the newly independent government of Kazakhstan has facilitated the in-migration of 944,000 Kazakhs from neighboring countries, with the majority migrating as family units. Using the post-Soviet repatriation of Kazakhs as an example, we illustrate in this article how socially constituted notions about gender and kinship help reinforce institutional and informal power structures that favor men at three different points in the migration process: in making the decision to migrate, in dealing with the bureaucratic aspects of migration, and in facing the consequences of migration. First, patriarchal power dynamics often mean that women have less influence than men on the decision to migrate. Second, the legal framework for repatriation is based on an implicit assumption that Kazakh households correspond to a patriarchal model, and this has financial consequences for women. Third, transnational migration widens the physical separations from natal kin that women already experience due to Kazakh kinship practices that emphasize patrilineal descent, clan-based exogamy, and patrilocal marriage. [gender, migration, kinship, transnational, Central Asia]

Mammoth Mountain, California, is a dacitic volcano that has experienced several periods of unrest since 1989. The onset of diffuse soil CO2 emissions at numerous locations on the flanks of the volcano began in 1989–1990 following an 11-month period of heightened seismicity. CO2 emission rates were measured yearly from 1995 to 2013 at Horseshoe Lake (HSL), the largest tree kill area on Mammoth Mountain, and measured intermittently at four smaller degassing areas around Mammoth from 2006 to 2013. The long-term record at HSL shows decadal-scale variations in CO2 emissions with two peaks in 2000–2001 and 2011–2012, both of which follow peaks in seismicity by 2–3 years. Between 2000 and 2004 emissions gradually declined during a seismically quiet period, and from 2004 to 2009 were steady at ~ 100 metric tonnes per day (t d− 1). CO2 emissions at the four smaller tree-kill areas also increased by factors of 2–3 between 2006 and 2011–2012, demonstrating a mountain-wide increase in degassing. Delays between the peaks in seismicity and degassing have been observed at other volcanic and hydrothermal areas worldwide, and are thought to result from an injection of deep CO2-rich fluid into shallow subsurface reservoirs causing a pressurization event with a delayed transport to the surface. Such processes are consistent with previous studies at Mammoth, and here we highlight (1) the mountain-wide response, (2) the characteristic delay of 2–3 years, and (3) the roughly decadal reoccurrence interval for such behavior. Our best estimate of total CO2 degassing from Mammoth Mountain was 416 t d− 1 in 2011 during the peak of emissions, over half of which was emitted from HSL. The cumulative release of CO2 between 1995 and 2013 from diffuse emissions is estimated to be ~ 2–3 Mt, and extrapolation back to 1989 gives ~ 4.8 Mt. This amount of CO2 release is similar to that produced by the mid-sized (VEI 3) 2009 eruption of Redoubt Volcano in Alaska (~ 2.3 Mt over 11 months), and significantly lower than long-term emissions from hydrothermal areas such as Solfatara in Campi Flegrei, Italy (16 Mt over 28 years).

The quantification of heat and mass flow between deep reservoirs and the surface is important for understanding magmatic and hydrothermal systems. Here, we use high-resolution measurement of carbon dioxide flux (φCO2) and heat flow at the surface to characterize the mass (CO2 and steam) and heat released to the atmosphere from two magma-hydrothermal systems. Our soil gas and heat flow surveys at Rotokawa and White Island in the Taupō Volcanic Zone, New Zealand, include over 3000 direct measurements of φCO2 and soil temperature and 60 carbon isotopic values on soil gases. Carbon dioxide flux was separated into background and magmatic/hydrothermal populations based on the measured values and isotopic characterization. Total CO2 emission rates (ΣCO2) of 441 ± 84 t d−1 and 124 ± 18 t d−1 were calculated for Rotokawa (2.9 km2) and for the crater floor at White Island (0.3 km2), respectively. The total CO2 emissions differ from previously published values by +386 t d−1 at Rotokawa and +25 t d−1 at White Island, demonstrating that earlier research underestimated emissions by 700% (Rotokawa) and 25% (White Island). These differences suggest that soil CO2 emissions facilitate more robust estimates of the thermal energy and mass flux in geothermal systems than traditional approaches. Combining the magmatic/hydrothermal-sourced CO2 emission (constrained using stable isotopes) with reservoir H2O:CO2 mass ratios and the enthalpy of evaporation, the surface expression of thermal energy release for the Rotokawa hydrothermal system (226 MWt) is 10 times greater than the White Island crater floor (22.5 MWt).

How do ancestors help Kazakhs cope with social and political problems in contemporary Kazakhstan? Living Language in Kazakhstan addresses this question, while offering a fascinating new perspective...

Throughout Central Asia, the end of communism has been marked by a significant change in the management and influence of local mosques. In many rural areas, small underground mosques operated by informally trained, elderly moldas have been supplanted by newly constructed mosques led by younger, foreign-educated local imams and financed by governmental and private donations from Turkey, Saudi Arabia, and other countries. From several perspectives, this ‘revival’ of Islam is characterized in a way that implies that increased religiosity and piety is somewhat problematic. In this essay, based on six months of ethnographic fieldwork in Western Mongolia, we argue that such an approach prevents an understanding of how religious changes are enhancing the social and material well-being of certain actors. We explore the utility of the concept of well-being by focusing on the everyday lives of Kazakh imams in Western Mongolia. Approximately 100,000 ethnic Kazakhs live in the Western Mongolian province of Bayan-Olgi...

Ultraviolet (UV) camera systems represent an exciting new technology for measuring two dimensional sulfur dioxide (SO 2 ) distributions in volcanic plumes. The high frame rate of the cameras allows the retrieval of SO 2 emission rates at time scales of 1 Hz or higher, thus allowing the investigation of high-frequency signals and making integrated and comparative studies with other high-data-rate volcano monitoring techniques possible. One drawback of the technique, however, is the limited spectral information recorded by the imaging systems. Here, a framework for simulating the sensitivity of UV cameras to various SO 2 distributions is introduced. Both the wavelength-dependent transmittance of the optical imaging system and the radiative transfer in the atmosphere are modeled. The framework is then applied to study the behavior of different optical setups and used to simulate the response of these instruments to volcanic plumes containing varying SO 2 and aerosol abundances located at various distances from the sensor. Results show that UV radiative transfer in and around distant and/or optically thick plumes typically leads to a lower sensitivity to SO 2 than expected when assuming a standard Beer–Lambert absorption model. Furthermore, camera response is often non-linear in SO 2 and dependent on distance to the plume and plume aerosol optical thickness and single scatter albedo. The model results are compared with camera measurements made at Kilauea Volcano (Hawaii) and a method for integrating moderate resolution differential optical absorption spectroscopy data with UV imagery to retrieve improved SO 2 column densities is discussed.

Filter pack data from six airborne campaigns at Redoubt Volcano, Alaska are reported here. These measurements provide a rare constraint on Cl output from an andesitic eruption at high emission rate (> 104 t d− 1 SO2). Four S/Cl ratios measured during a period of lava dome growth indicate a depth of last magma equilibration of 2–5 km. The S/Cl ratios in combination with COSPEC SO2 emission rate measurements indicate HCl emission rates of 1500–3600 t d− 1 during dome growth. SO2 and HCl emission rates at Redoubt Volcano correlate with each other and were low prior to the eruption, high during the eruption, and low after the eruption. S/Cl ratios measured by filter pack at andesitic volcanoes have a small range of variance, with no clear trends seen for eruptive versus passive activity. The very few S/Cl ratio measurements by filter pack at andesitic volcanoes are not as predictive of future volcanic activity as has been demonstrated for basaltic volcanoes. This may be because there are so few of these measurements. We have demonstrated it is possible to collect these samples by air between explosions during lava dome-building eruptions. We recommend more filter pack sampling be performed at andesitic volcanoes to determine the technique's utility for volcano monitoring. Filter pack data has been demonstrated to be useful for calculating the depth of magma equilibration at volcanoes including Redoubt Volcano.

The 2009 eruption of Redoubt Volcano, Alaska, provided a rare opportunity to compare satellite measurements of sulfur dioxide (SO2) by the Ozone Monitoring Instrument (OMI) with airborne SO2 measurements by the Alaska Volcano Observatory (AVO). Herein we: (1) compare OMI and airborne SO2 column density values for Redoubt's tropospheric plume, (2) calculate daily SO2 masses from Mount Redoubt for the first three months of the eruption, (3) develop simple methods to convert daily measured SO2 masses into emission rates to allow satellite data to be directly integrated with the airborne SO2 emissions dataset, (4) calculate cumulative SO2 emissions from the eruption, and (5) evaluate OMI as a monitoring tool for high-latitude degassing volcanoes. A linear correlation (R2 ~ 0.75) is observed between OMI and airborne SO2 column densities. OMI daily SO2 masses for the sample period ranged from ~ 60.1 kt on 24 March to below detection limit, with an average daily SO2 mass of ~ 6.7 kt. The highest SO2 emissions were observed during the initial part of the explosive phase and the emissions exhibited an overall decreasing trend with time. OMI SO2 emission rates were derived using three methods and compared to airborne measurements. This comparison yields a linear correlation (R2 ~ 0.82) with OMI-derived emission rates consistently lower than airborne measurements. The comparison results suggest that OMI's detection limit for high latitude, springtime conditions varies from ~ 2000 to 4000 t/d. Cumulative SO2 masses calculated from daily OMI data for the sample period are estimated to range from 542 to 615 kt, with approximately half of this SO2 produced during the explosive phase of the eruption. These cumulative masses are similar in magnitude to those estimated for the 1989–90 Redoubt eruption. Strong correlations between daily OMI SO2 mass and both tephra mass and acoustic energy during the explosive phase of the eruption suggest that OMI data may be used to infer relative eruption size and explosivity. Further, when used in conjunction with complementary datasets, OMI daily SO2 masses may be used to help distinguish explosive from effusive activity and identify changes in lava extrusion rates. The results of this study suggest that OMI is a useful volcano monitoring tool to complement airborne measurements, capture explosive SO2 emissions, and provide high temporal resolution SO2 emissions data that can be used with interdisciplinary datasets to illuminate volcanic processes.

For 24 h we measured continuously the variability of atmospheric refractivity over a volcano on the tropical island of Montserrat using a ground-based radar interferometer. We observed variations in phase that we interpret as due to changing water vapour on the propagation path between the radar and the volcano and we present them here in the context of the behaviour of the atmospheric boundary layer over the island. The water vapour behaviour was forced by diurnal processes, the passage of a synoptic-scale system and the presence of a plume of volcanic gas. The interferometer collected images of amplitude and phase every minute. From pairs of phase images, interferograms were calculated and analyzed every minute and averaged hourly, together with contemporaneous measurements of zenith delays estimated from a network of 14 GPS receivers. The standard deviation of phase at two sites on the volcano surface spanned a range of about 1–5 radians, the lowest values occurring at night on the lower slopes and the highest values during the day on the upper slopes. This was also reflected in spatial patterns of variability. Two-dimensional profiles of radar-measured delays were modelled using an atmosphere with water vapour content decreasing upwards and water vapour variability increasing upwards. Estimates of the effect of changing water vapour flux from the volcanic plume indicate that it should contribute only a few percent to this atmospheric variability. A diurnal cycle within the lower boundary layer producing a turbulence-dominated mixed layer during the day and stable layers at night is consistent with the observed refractivity.

Volcanoes with crater lakes and/or extensive hydrothermal systems pose significant challenges with respect to monitoring and forecasting eruptions, but they also provide new opportunities to enhance our understanding of magmatic–hydrothermal processes. Their lakes and hydrothermal systems serve as reservoirs for magmatic heat and fluid emissions, filtering and delaying the surface expressions of magmatic unrest and eruption, yet they also enable sampling and monitoring of geochemical tracers. Here, we describe the outcomes of a highly focused international experimental campaign and workshop carried out at Kawah Ijen volcano, Indonesia, in September 2014, designed to answer fundamental questions about how to improve monitoring and eruption forecasting at wet volcanoes. Geological Society, London, Special Publications

Carbon dioxide emissions and heat flow have been determined from the Ohaaki hydrothermal field, Taupo Volcanic Zone (TVZ), New Zealand following 20 a of production (116 MW e ). Soil CO 2 degassing was quantified with 2663 CO 2 flux measurements using the accumulation chamber method, and 2563 soil temperatures were measured and converted to equivalent heat flow (W m −2 ) using published soil temperature heat flow functions. Both CO 2 flux and heat flow were analysed statistically and then modelled using 500 sequential Gaussian simulations. Forty subsoil CO 2 gas samples were also analysed for stable C isotopes. Following 20 a of production, current CO 2 emissions equated to 111 ± 6.7 T/d. Observed heat flow was 70 ± 6.4 MW, compared with a pre-production value of 122 MW. This 52 MW reduction in surface heat flow is due to production-induced drying up of all alkali–Cl outflows (61.5 MW) and steam-heated pools (8.6 MW) within the Ohaaki West thermal area (OHW). The drying up of all alkali–Cl outflows at Ohaaki means that the soil zone is now the major natural pathway of heat release from the high-temperature reservoir. On the other hand, a net gain in thermal ground heat flow of 18 MW (from 25 MW to 43.3 ± 5 MW) at OHW is associated with permeability increases resulting from surface unit fracturing by production-induced ground subsidence. The Ohaaki East (OHE) thermal area showed no change in distribution of shallow and deep soil temperature contours despite 20 a of production, with an observed heat flow of 26.7 ± 3 MW and a CO 2 emission rate of 39 ± 3 T/d. The negligible change in the thermal status of the OHE thermal area is attributed to the low permeability of the reservoir beneath this area, which has limited production (mass extraction) and sheltered the area from the pressure decline within the main reservoir. Chemistry suggests that although alkali–Cl outflows once contributed significantly to the natural surface heat flow (∼50%) they contributed little ( 2 emissions due to the loss of >99% of the original CO 2 content due to depressurisation and boiling as the fluids ascended to the surface. Consequently, the soil has persisted as the major (99%) pathway of CO 2 release to the atmosphere from the high temperature reservoir at Ohaaki. The CO 2 flux and heat flow surveys indicate that despite 20 a of production the variability in location, spatial extent and magnitude of CO 2 flux remains consistent with established geochemical and geophysical models of the Ohaaki Field. At both OHW and OHE carbon isotopic analyses of soil gas indicate a two-stage fractionation process for moderate-flux (>60 g m −2 d −1 ) sites; boiling during fluid ascent within the underlying reservoir and isotopic enrichment as CO 2 diffuses through porous media of the soil zone. For high-flux sites (>300 g m −2 d −1 ), the δ 13 CO 2 signature (−7.4 ± 0.3‰ OHW and −6.5 ± 0.6‰ OHE) is unaffected by near-surface (soil zone) fractionation processes and reflects the composition of the boiled magmatic CO 2 source for each respective upflow. Flux thresholds of −2 d −1 for purely diffusive gas transport, between 30 and 300 g m −2 d −1 for combined diffusive–advective transport, and ⩾300 g m −2 d −1 for purely advective gas transport at Ohaaki were assigned. δ 13 CO 2 values and cumulative probability plots of CO 2 flux data both identified a threshold of ∼15 g m −2 d −1 by which background (atmospheric and soil respired) CO 2 may be differentiated from hydrothermal CO 2 .