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Nontuberculous mycobacteria (NTM) are environmentally acquired opportunistic pathogens that can cause chronic lung disease. Within the U.S., Hawai'i shows the highest prevalence rates of NTM lung infections. Here, we investigated a potential role for active volcanism at the Kīlauea Volcano located on Hawai'i Island in promoting NTM growth and diversity. We recovered NTM that are known to cause lung disease from plumbing biofilms and soils collected from the Kīlauea environment. We also discovered viable Mycobacterium avium, Mycobacterium abscessus, and Mycobacterium intracellulare subsp. chimaera on volcanic ash collected during the 2018 Kīlauea eruption. Analysis of soil samples showed that NTM prevalence is positively associated with bulk content of phosphorus, sulfur, and total organic carbon. In growth assays, we showed that phosphorus utilization is essential for proliferation of Kīlauea‐derived NTM, and demonstrate that NTM cultured with volcanic ash adhere to ash surfaces and remain viable. Ambient dust collected on O'ahu concurrent with the 2018 eruption contained abundant fresh volcanic glass, suggestive of inter‐island ash transport. Phylogenomic analyses using whole genome sequencing revealed that Kīlauea‐derived NTM are genetically similar to respiratory isolates identified on other Hawaiian Islands. Consequently, we posit that volcanic eruptions could redistribute environmental microorganisms over large scales. While additional studies are needed to confirm a direct role of ash in NTM dispersal, our results suggest that volcanic particulates harbor and can redistribute NTM and should therefore be studied as a fomite for these burgeoning, environmentally acquired respiratory infections. Plain Language Summary: Nontuberculous mycobacteria (NTM) can cause environmentally acquired lung infections in susceptible individuals. While NTM infections are linked to household exposures, there are likely non‐household routes of acquisition. Hawai'i is a geographic hotspot for NTM lung disease, but the island‐specific environmental niches for NTM remain poorly understood. Thus, a greater knowledge of where susceptible individuals acquire their infections is an important public health endeavor that may lead to actions to mitigate potential sources of NTM exposures. In the current work, we show that particulate matter collected from Kīlauea Volcano on Hawai'i Island harbors Mycobacterium avium, Mycobacterium abscessus, and Mycobacterium intracellulare subsp. chimaera. Microbiologic, environmental, and NTM genetic data demonstrate that volcanic ash may act as a novel vehicle for the dispersal of clinically relevant NTM. Key Points: Long‐range transport of hitch‐hiking infectious agents has never been reported for volcanic eruptions globallyAsh recovered from the 2018 Kīlauea Volcano eruption harbors species of nontuberculous mycobacteria (NTM) known to cause lung diseaseGenomic evaluation reveals Kīlauea‐derived NTM are genetically similar to respiratory isolates identified on other Hawaiian Islands [ABSTRACT FROM AUTHOR]

The Pah Tempe hot springs discharge ~260 L/s of water at ~40[degrees]C into the Virgin River in the footwall damage zone of the Hurricane fault at Timpoweap Canyon, near Hurricane, Utah, USA. Although these are Na-Cl waters, they actively discharge C[O.sub.2] gas and contain significant quantities of C[O.sub.2] (~34.6 mmol/kg), predominantly as [H.sub.2]C[O.sub.3] and HC[O.sup.-.sub.3]. Because of excellent exposures, Pah Tempe provides an exceptional opportunity to observe the effects of enhanced fracture permeability in an active extensional fault. Pah Tempe waters have been deeply circulated (>5 km; >150[degrees]C) into basement rock as illustrated by the clear water-rock exchange of oxygen isotopes. Waters were probably recharged under colder climate conditions than present and therefore have a prolonged subsurface residence. Discharge of both water and gas in the springs correlates to the density of fractures in carbonate rocks above stream level. This observation suggests that clusters of high fracture density in the fault-damage zone act as pathways from the likely regional aquifer, the eolian Queantoweap Sandstone, through the overlying confining unit, the gypsiferous silty Seligman Member of the Kaibab Formation. Mass-balance modeling suggests that the majority of C[O.sub.2] discharge is the product of the quantitative dissolution of C[O.sub.2] gas at depth within the fault zone. Upon discharge, most of the carbon is released to the surface as dissolved species. It appears that the subsurface production rate of C[O.sub.2] is relatively low because Pah Tempe waters are grossly under-saturated in C[O.sub.2] at inferred minimum circulation depths and temperatures. Geological and geochemical data also suggest that the C[O.sub.2] is dominated by a crustal component complemented by minor mantle contributions. Keywords: hydrogeology, C[O.sub.2] flux, damage zone, aqueous geochemistry, structural geology.

New and reinterpreted isotopic data for crystalline rocks exposed in the Wasatch Range require a reevaluation of Precambrian crustal boundaries in Utah. Crystalline rocks of the Santaquin Complex underwent metamorphism prior to ca. 1670 Ma, consistent with Sr and Nd isotope data. Mafic to intermediate rocks have major element, trace element, and isotope ratios indicative of derivation in an arc accreted to the Archean craton in Proterozoic time, requiring the crustal suture to be north of the Santaquin Complex. Farther north, the Farmington Canyon Complex has been considered Archean based on published Nd model ages and discordant U/Pb zircon ages. However, Nd model ages and zircons could be inherited from sedimentary protoliths. U/Pb and electron microprobe ages of monazite have a mode at 1650 to 1700 Ma, concordant with the Santaquin Complex, and lack inheritance. We propose that the Farmington Canyon Complex was first cratonized from Archean-derived sediments in the Proterozoic, requiring a crustal suture to be north of it as well. Accretion ages of arc terranes in southeastern Wyoming are ~60-100 m.y. older than in Utah. Thus, a serious reevaluation of basement architecture in Utah is needed and a previously unrecognized temporal complexity of accretion is indicated. Keywords: geochronology, igneous rocks, crustal origin, isotope geochemistry.

Late Cenozoic (

Published K-Ar ages of laccoliths of the Henry and La Sal Mountains range from 23 to 56 Ma, with a bimodal distribution in the Eocene and late Oligocene epochs. Eocene ages require a period of magmatism during the Laramide Orogeny, a time of little or no igneous activity in the western United States at these latitudes. On the basis of 40Ar/39Ar and fission-track ages, we conclude that intrusive activity occurred during middle to late Oligocene and early Miocene time (31-20 Ma) in the Henry, La Sal, and Abajo Mountains. These results imply a genetic link to magmatism in the Reno-Marysvale and San Juan volcanic fields, which lie to the west and east of the Colorado Plateau, respectively. We interpret the small volume of the Iaccoliths, relative to the surrounding volcanic fields, to reflect differences in crustal composition and tectonic history of the plateau and adjacent areas. Eocene K-Ar ages result from excess 40Ar or contamination by xenocyrsts. Excess argon is manifested by trapped argon with 40Ar/36Ar ratios greater than atmosphere (295.5), resulting in total-gas or apparent K-Ar ages that are too old. Laser-fusion experiments and microprobe data show that some samples with Eocene or older total-gas ages and uncorrelated inverse correlation plots are affected by radiogenic argon residing in incompletely outgassed hornblende xenocrysts. All such samples contain middle- to late-Oligocene magmatic hornblende crystals as revealed by laser-fusion experiments. Xenocrysts may be derived from amphibolite xenoliths common in these rocks. Mixing calculations indicate that only 1%-4% contamination may be required to increase K-Ar ages by 10-15 Ma for xenocrysts outgassed as much as 75%. The 40Ar/39Ar method is capable of identifying small degrees of magmatic contamination by older K-bearing phases.

A study was conducted on sieve-textured plagioclase found in orogenic volcanic rocks formed by rapid decompression. The plagioclasetexture was previously interpreted as a result of magma mixing but may occur via rapid decompression. High-pressure piston-cylinder experiments on an andesite showed that the presence of sieve-textured plagioclase should not onlybe attributed to magma mixing but to rapid decompression as well. Further experimentation also revealed that rapid decompression may occur in conjunctionwith magma mixing.

Tufa (spring) deposits in the Tecopa basin, California, reflect the response of arid groundwater regimes to wet climate episodes. Two types of tufa are represented, informally defined as (1) an easily disaggregated, fine-grained mixture of calcite and quartz (friable tufa) in the southwest Tecopa Valley, and (2) hard, vuggy micrite, laminated carbonate, and carbonate-cemented sands and gravels (indurated tufa) along the eastern margin of Lake Tecopa. High [Delta] [sup.18][O.sub.VSMOW] (Vienna standard mean ocean water) water values, field relations, and the texture of friable tufa suggest rapid nucleation of calcite as subaqueous, fault-controlled groundwater discharge mixed with high-pH, hypersaline lake water. Variations between [Delta][sup.18][O.sub.VSMOW] and [Delta] [sup.13][C.sub.PDB] (Peedee belemnite) values relative to other closed basin lakes such as the Great Salt Lake and Lake Lahontan suggest similarities in climatic and hydrologic settings. Indurated tufa, also fault controlled, formed mounds and associated feeder systems as well as stratabound carbonate-cemented ledges. Both deposits represent discharge of deeply circulated, high total dissolved solids, and high p[CO.sub.2] regional groundwater with kinetic enrichments of as much as several per mil for [Delta] [sup.18][O.sub.VSMOW] values. Field relations show that indurated tufa represents episodic discharge, and U-series ages imply that discharge was correlated with cold, wet climate episodes. In response to both the breaching of the Tecopa basin and a modern arid climate, most discharge has changed from fault-controlled locations near basin margins to topographic lows of the Amargosa River drainage at elevations 30-130 m lower. Because of episodic climate change, spring flows may have relocated from basin margin to basin center multiple times. Keywords: hydrology, isotope geochemistry, nuclear waste, paleoclimate, paleohydrology.

Younger Dryas to earliest Holocene mega-landslides (>10 km2) in the eastern Fish Lake Plateau of central Utah required unusually wet conditions to drive movement. The sediment from abundant small lakes, ponds and especially fens that formed in swales between hummocks on the landslide surfaces are excellent archives of past climate. An integrated geophysical, geochemical and micro-palaeontological investigation characterized fen deposits, determining the timing of mass movement and establishing the subsequent climate history of the region. High-resolution P-(compressional) wave surveys of fen deposits were conducted to image fen-landslide contacts. Past climate states were assessed through loss on ignition, pollen and diatom abundances. Diatoms, in particular, record large variations in precipitation as the present-day wetland switched from fen (intermittent standing water) to pond states in response to variable precipitation. One core was analysed for detailed climate proxies. A wet episode (pond) prevailed from 11.5 to 10 ka after which the climate became much drier (fen) until 6 ka due to weakening of the North American Monsoon. After 2.5-2.0 ka, reduced insolation produced cooler summers and wet winters (pond). Only recently (<500 years) has a fen re-emerged based on direct observation and the disappearance of diatoms that require standing water. 14C ages of basal sediment from four cores show two episodes of movement: 12.8-12.5 and 10.5 ka. The earlier ages indicate that Younger Dryas high effective precipitation caused mass wasting. Later, during early Holocene times, colder winters followed by warmer summers and vigorous monsoons drove movement as rapid spring snow-melt was followed by wet summers. In broad terms, this work highlights variable climate conditions that can drive mass movement, as well as the sensitivity of diatom records in fens to effective precipitation. [ABSTRACT FROM AUTHOR]