Brenda Beitler Bowen

Hydrogeologic Controls on Induced Seismicity in Crystalline Basement Rocks Due to Fluid Injection into Basal Reservoirs

A series of Mb 3.8-5.5 induced seismic events in the midcontinent region, United States, resulted from injection of fluid either into a basal sedimentary reservoir with no underlying confining unit or directly into the underlying crystalline basement complex. The earthquakes probably occurred along faults that were likely critically stressed within the crystalline basement. These faults were located at a considerable distance (up to 10 km) from the injection wells and head increases at the hypocenters were likely relatively small (∼70-150 m). We present a suite of simulations that use a simple hydrogeologic-geomechanical model to assess what hydrogeologic conditions promote or deter induced seismic events within the crystalline basement across the midcontinent. The presence of a confining unit beneath the injection reservoir horizon had the single largest effect in preventing induced seismicity within the underlying crystalline basement. For a crystalline basement having a permeability of 2 × 10(-17)  m(2) and specific storage coefficient of 10(-7) /m, injection at a rate of 5455 m(3) /d into the basal aquifer with no underlying basal seal over 10 years resulted in probable brittle failure to depths of about 0.6 km below the injection reservoir. Including a permeable (kz  = 10(-13)  m(2) ) Precambrian normal fault, located 20 m from the injection well, increased the depth of the failure region below the reservoir to 3 km. For a large permeability contrast between a Precambrian thrust fault (10(-12)  m(2) ) and the surrounding crystalline basement (10(-18)  m(2) ), the failure region can extend laterally 10 km away from the injection well.

Red rock and red planet diagenesis: Comparisons of Earth and Mars concretions

Compelling similarities between concretions on Earth and “blueberries” on Mars are used to suggest the blueberries are concretions that formed from a history of watery diagenesis. In the terrestrial examples, groundwater flow produces variations in sandstone color and iron oxide concretions in the Jurassic Navajo Sandstone of Utah. Variations in concretion mineralogy, form, and structure reflect different conditions at chemical reaction fronts, the influence of preferential fluid flow paths, the relative roles of advection and diffusion during precipitation, the presence of multiple events, fluid geochemistry, and time. The terrestrial concretions are analogs that can be used to understand the water-saturated conditions that formed spherical hematite concretions on Mars.

Mechanisms of PETM global change constrained by a new record from central Utah

Catastrophic carbon release and global warming during the Paleocene-Eocene thermal maximum (PETM) profoundly affected continental climate and ecosystems. Understanding of the details and mechanisms of these effects is limited by the poor geographic coverage of existing continental PETM records. Here, we extend the record of this event in North America through identification of the PETM carbon isotope excursion within a sequence of paleosols in the North Horn Formation of central Utah, some 500 km to the south of previous records from northern Wyoming. Data from the new site suggest that patterns of climatological change were similar across a meridional transect of western North America but that PETM climate was relatively more arid in the southern Rocky Mountains, possibly reflecting diversion of precipitation from middle to high latitudes. Our results are consistent with two proposed mechanisms explaining variation in the amplitude of continental PETM carbon isotope records in terms of changes in floral composition or varying environmental wetness, and they present opportunities for future tests of proposed north-south biotic dispersal during the PETM.

Reflectance spectroscopic mapping of diagenetic heterogeneities and fluid-flow pathways in the Jurassic Navajo Sandstone

Multiple episodes of fluids migrating through the Jurassic Navajo Sandstone have resulted in abundant and spatially variable diagenetic mineral changes. Depending on fluid chemistry, flow events have produced or removed varying amounts of iron oxides, clays, and carbonates with distinctive spectral reflectance signatures that can be used to map spatial heterogeneities in diagenetic mineralogy and paleofluid-migration pathways (including hydrocarbons and groundwaters). Field and laboratory reflectance spectroscopy shows that the common diagenetic minerals in the Navajo Sandstone have diagnostic visible, near-infrared, and short-wave infrared spectral characteristics in the 0.35–2.5-m range. Comparisons of (1) geochemical data, (2) in-situ reflectance spectroscopy, and (3) airborne imaging spectroscopy for zones of variably altered Navajo Sandstone in southern Utah show that the minerals within alteration facies have distinctive spectral signatures. Reflectance spectroscopic mapping provides a method for evaluating the effects of diagenesis and fluids in this well-exposed reservoir sandstone. Reservoir heterogeneity in many eolian sandstones is largely controlled by diagenetic processes that can be difficult to evaluate on outcrop to reservoir scales (approximately tens to hundreds of meters to several kilometers). Imaging spectroscopy allows for the evaluation of mineralogy variations on these scales. The patterns of authigenic iron oxide, clay, and carbonate removal and precipitation trace the paths of different episodes of fluid flow and sandstone alteration. Mineral variations occur as kilometer-scale reaction fronts related to structural fluid conduits and as 100-m (330-ft)-scale changes that follow stratigraphy. These spectroscopic techniques provide important tools for reservoir evaluation, and the patterns observed serve as an analog to understanding regional diagenetic patterns in other subsurface eolian reservoirs.

Fluctuations in Sedimentary Provenance of the Upper Cambrian Mount Simon Sandstone, Illinois Basin, United States

Understanding sedimentary provenance is essential when investigating clastic strata. The lack of compositional variability in mature sediments associated with Cambrian cratonic sequences in the United States makes traditional petrographic discrimination of sedimentary origin difficult. The upper Cambrian Mount Simon Sandstone of the Illinois Basin is a quartz arenite (Q93F5L2 and Qm85F5Lt10) with unconstrained sediment provenance and is also the reservoir for ongoing injection of a million tons of CO2. This study investigates whether fluctuations in sedimentary provenance caused changes in the composition and texture of the Mount Simon Sandstone reservoir through its deposition. Core descriptions, petrographic analyses of 35 thin sections, and LA-ICPMS analyses of five detrital zircon samples, collected from 878 feet of the Mount Simon Sandstone depositional interval in Stephenson County, Illinois, the only known core that includes the entire formation, yield new compositional data and U-Pb ages. Compositional heterogeneities observed from the top to the bottom along the core, including changes in polycrystalline quartz (from 1% to 22%) and feldspar (from 0% to 19%), suggests provenance change during Mount Simon Sandstone deposition. Seven U-Pb age populations, from 487 detrital zircon grains, correspond to Laurentian source terranes: Superior (2780–2570 and 3000–2800 Ma), Penokean (1990–1800 Ma), Central Plains (1700–1620 and 1790–1750 Ma), Granite-Rhyolite (1500–1300 Ma), and Grenville and Midcontinent Rift (1280–1023 Ma). Variations in detrital zircon age spectra correlate with compositional changes, representing changes in sedimentary provenance that occurred during the Late Cambrian. Early in Mount Simon Sandstone deposition, braided fluvial systems transported detritus from Archean and Mesoproterozoic sources. A shift to marine-influenced deltas led to sourcing from predominantly Archean terranes. We hypothesize that a sea level rise obscured proximal sources and drove headwater incision cratonward.

Mechanisms of PETM global change constrained by a new record from central Utah: COMMENT and REPLY COMMENT

[Bowen and Bowen (2008)][1] proposed increased aridity at the Paleocene-Eocene boundary carbon-cycle perturbation, whereas my study ([Retallack, 2005][2]) found increased rainfall. Their interpretation of climatic drying during a past CO2 spike is also at variance with predictions of increased

Institutionalizing interdisciplinary sustainability curriculum at a large, research-intensive university: challenges and opportunities

As universities and colleges seek to integrate sustainability into a broad range of programs, degrees, and certificates, they must overcome traditional academic silos, disciplinary boundaries, and funding constraints. This requires an unprecedented level of curricular innovation, creative funding streams, and directed facilitation of cross-campus collaboration and communication. This article describes and analyzes recent efforts at the University of Utah to dramatically enhance interdisciplinary sustainability curriculum by utilizing a broad set of tools, including the creation of new faculty and staff positions, faculty learning communities, and special seminars; the development of new degrees and certificates; and the innovative changes in University structure and administration. The authors focus on the role of program coherence, administration, and ongoing support and assessment, as well as network building and systemic innovation that incentivize interdisciplinary sustainability teaching and curriculum development.

Insights into Lake Bonneville Using Remote Sensing and Digital Terrain Tools

Abstract Beginning in the mid-20th century, the remote-sensing technologies of photogrammetry, LiDAR, and imaging spectroscopy have been a boon to the study of surficial processes throughout the world. Lake Bonneville research has benefited from these technologies ever since the advent of aerial photography, although each technology has its own particular strengths and weaknesses. Examples include elucidation of geomorphic features such as faint shorelines and investigation of mineralogy of playas resulting from the evaporation of Lake Bonneville. Future innovations promise to build on this rich legacy of Bonneville research.

Sphere of Sustainability: Lessons from the University of Utah’s Global Changes and Society Course

AbstractGlobal challenges increasingly require interdisciplinary approaches to problem solving. This need should be facilitated by institutions of higher education. With increasing climatic and anthropogenic changes, graduate students must gain collaborative experience communicating and working across disciplines. The evolution of multidisciplinary problem-solving and global, sustainability-minded education provides the impetus for universities to reframe researchers’ understanding of the environment and reimagine the spheres of curriculum, research, teaching, outreach, culture, and management. This paper describes a successful multidisciplinary approach at the University of Utah, centered on the project-based Global Changes and Society course. This method has brought about changes within the university and improved linkages to the greater community. Of particular importance is the development and implementation of the course framework, which transitions over time to address region-specific sustainability...

Follow the water: Connecting a CO2 reservoir and bleached sandstone to iron-rich concretions in the Navajo Sandstone of south-central Utah, USA: COMMENT

Concretions comprise an important diagenetic record of fluid flow in the Jurassic Navajo Sandstone (Utah, United States). Mobilization and transport of chemically reduced Fe+2 in solution likely occurs via groundwater with CH4 or other hydrocarbons as reducing agents ([Beitler et al., 2003][1]; [