Physical Sciences and Mathematics Commons^™

Reflectance Spectroscopy Datasets For The Validation Of Tanager, Kristiana Lapo, Kathleen Hoza, Sammy Theuer, Melissa S. Rice

Geology Faculty Publications

The Three-Axis N-sample Automated Goniometer for Evaluating Reflectance (TANAGER) is a custom goniometer designed to rapidly acquire spectra of natural rock surfaces across the full scattering hemisphere. TANAGER interfaces with a Malvern Panalytical ASD Fieldspec 4 Hi-Res reflectance spectrometer to collect data from 350-2500 nm at a range of incidence, emission and azimuth angles. To validate the accuracy and repeatability of data collected with TANAGER - and to characterize any instrument noise, artifacts or sample heating effects - we collected spectra from three categories of targets: (1) powdered calcium sulfate (anhydrite), (2) naturally weathered basalt surfaces, and (3) color calibration …

2023’S Billion-Dollar Disasters List Shattered The Us Record With 28 Big Weather And Climate Disasters Amid Earth’S Hottest Year On Record, Shuang-Ye Wu

Geology Faculty Publications

The U.S. set an unwelcome record for weather and climate disasters in 2023, with 28 disasters that exceeded more than US$1 billion in damage each.

While it wasn’t the most expensive year overall – the costliest years included multiple hurricane strikes – it had the highest number of billion-dollar storms, floods, droughts and fires of any year since counting began in 1980, with six more than any other year, accounting for inflation.

Mastcam Multispectral Database From The Curiosity Rover’S Traverse In Gale Crater, Mars (Sols 0-2302), Melissa S. Rice

Geology Faculty Publications

The Mars Science Laboratory (MSL) Curiosity rover has explored fluvio-deltaic, lacustrine, and aeolian strata as it climbed over 400 m in elevation over the first 2302 sols of its traverse. Curiosity’s Mast Camera (Mastcam) instrument is a pair of multispectral imagers covering visible to near-infrared (VNIR) wavelengths (445 nm - 1013 nm). Mastcam spectra can broadly distinguish between iron phases and oxidation states, and in combination with chemical data from other instruments, Mastcam spectra can help constrain mineralogy, depositional origin, and diagenesis. This dataset includes representative Mastcam spectra from >600 multispectral observations acquired across Curiosity’s traverse through Vera Rubin ridge …

Google Earth Model Of The Southern Alisitos Arc Crustal Section, Baja California, Rebecca Morris, Sarah Medynski, Susan M. Debari, Cathy Busby

Geology Faculty Publications

The Cretaceous Alisitos Ocean Arc 3D Model version 1 (v1) is a publically accessible and interactive 3D arc crustal model, with geologic map overlays on Google Earth. The model provides a virtual field trip through the upper- to middle-crust transition in the exhumed 110 Ma southern Alisitos Arc, Baja California, Mexico. This region was chosen for the model as it exposes a structurally intact and minimally altered transition zone between heterogeneous volcanic upper crust through the underlying plutonic rocks (up to ~7 km deep). The model is organized into three paleo-volcanic centers, which include (from north to south): a northern …

Metamorphism Of The Sierra De Maz And Implications For The Tectonic Evolution Of The Mara Terrane, Andrew Tholt, Sean R. Mulcahy, William C. Mcclelland, Sarah M. Roeske, Vinícius T. Meira, Patricia Webber, Emily Houlihan, Matthew A. Coble, Jeffrey D. Vervoort

Geology Faculty Publications

The Mesoproterozoic MARA terrane of western South America is a composite igneous-metamorphic complex that is important for Paleozoic paleogeographic reconstructions and the relative positions of Laurentia and Gondwana. The magmatic and detrital records of the MARA terrane are consistent with a Laurentian origin; however, the metamorphic and deformation records lack sufficient detail to constrain the correlation of units within the MARA terrane and the timing and mechanisms of accretion to the Gondwana margin.

Combined regional mapping, metamorphic petrology, and garnet and monazite geochronology from the Sierra de Maz of northwest Argentina suggest that the region preserves four distinct litho-tectonic units …

Building Arc Crust: Plutonic To Volcanic Connections In An Extensional Oceanic Arc, The Southern Alisitos Arc, Baja California, Rebecca A. Morris, Susan M. Debari, Cathy Busby, Sarah Medynski, Brian R. Jicha

Geology Faculty Publications

The ~50 km long Rosario segment of the Cretaceous Alisitos oceanic arc terrane provides undeformed three-dimensional exposures of the upper 7 km of an oceanic extensional arc, where crustal generation processes are recorded in both the volcanic and underlying plutonic rocks. These exceptional exposures allow for the study of the physical and chemical links between the rock units and help constrain the differentiation processes active during the growth and evolution of arc crust. This study focuses on the southern third of the Rosario segment, previously referred to as the southern volcano-bounded basin, and its plutonic underpinnings. Upper crustal rocks in …

Subduction Initiation And Early Evolution Of The Easton Metamorphic Suite, Northwest Cascades, Washington, Jeremy L. Cordova, Sean R. Mulcahy, Elizabeth R. Schermer, Laura E. Webb

Geology Faculty Publications

The Easton metamorphic suite, in the northwest Cascades of Washington State, preserves an inverted metamorphic sequence with ultramafic rocks underlain by amphibolite and high-temperature blueschist juxtaposed above low-temperature blueschists. The sequence is interpreted as a metamorphic sole and younger accreted rocks that formed during and after the initiation of Farallon plate subduction beneath North America in Jurassic time. Two high-temperature deformation events are recorded in the metamorphic sole at ∼10 kbar and ∼760 °C to 590 °C between >167 and 164 Ma. High-temperature blueschist partly overprints the amphibolite but may have accreted separately at ∼530 °C between ca. 165 and …

Particle Size Specific Magnetic Properties Across The Norwegian‐Greenland Seas: Insights Into The Influence Of Sediment Source And Texture On Bulk Magnetic Records, Robert G. Hatfield, Benjamin H. Wheeler, Brendan T. Reilly, Joseph S. Stoner, Bernard A. Housen

Geology Faculty Publications

We make fundamental observations of the particle size variability of magnetic properties from 71 core tops that span the southern Greenland and Norwegian Seas. These data provide the first detailed regional characterization of how bulk magnetic properties vary with sediment texture, sediment source, and sediment transport. Magnetic susceptibility (MS) and hysteresis parameters were measured on the bulk sediment and the five constituent sediment particle size fractions (clay, fine silt, medium silt, coarse silt, and sand). The median MS value of the medium silt size fraction is ~3–5 times higher than that of the sand and clay size fractions and results …

Supplemental Data For 'Evolution And Controls Of Large Glacial Lakes In The Nepal Himalaya', Umesh K. Haritashya, Jeffrey S. Kargel, Dan H. Shugar, Gregory J. Leonard, Katherine Strattman, C. Scott Watson, David Shean, Stephan Harrison, Kyle T. Mandli, Dhananjay Regmi

Geology Faculty Publications

Supplementary data for the article "Evolution and Controls of Large Glacial Lakes in the Nepal Himalaya"

Evolution And Controls Of Large Glacial Lakes In The Nepal Himalaya, Umesh K. Haritashya, Jeffrey S. Kargel, Dan H. Shugar, Gregory J. Leonard, Katherine Strattman, C. Scott Watson, David Shean, Stephan Harrison, Kyle T. Mandli, Dhananjay Regmi

Geology Faculty Publications

Glacier recession driven by climate change produces glacial lakes, some of which are hazardous. Our study assesses the evolution of three of the most hazardous moraine-dammed proglacial lakes in the Nepal Himalaya—Imja, Lower Barun, and Thulagi. Imja Lake (up to 150 m deep; 78.4 x 10⁶ m³ volume; surveyed in October 2014) and Lower Barun Lake (205 m maximum observed depth; 112.3 x 10⁶ m³ volume; surveyed in October 2015) are much deeper than previously measured, and their readily drainable volumes are slowly growing. Their surface areas have been increasing at an accelerating pace from a …

Construction, Emplacement, And Geochemical Evolution Of Deep-Crustal Intrusions: Tenpeak And Dirtyface Plutons, North Cascades, Western North America, Robert B. Miller, Susan M. Debari, Scott R. Paterson

Geology Faculty Publications

Deep plutonic systems represent an important link between lower-crustal melt-generation sites and higher-level regions of magma accumulation, but models for these systems are limited by the relative scarcity of exposed weakly deformed, deep-crustal plutons. Exceptions include the ca. 92.3–89.7 Ma, dominantly tonalitic Tenpeak pluton and the smaller, nearby ca. 91 Ma Dirtyface pluton of the North Cascades (western North America), which represent deeply exposed crustal levels (∼25–35 km) of a Cordilleran arc. Initial subduction-driven magmatism in the Tenpeak pluton was marked by co-magmatic hydrous mafic and felsic magmas, which formed gabbro, diorite, tonalite, and hornblendite within a heterogeneous mafic complex. …

Climate Change And The Global Pattern Of Moraine-Dammed Glacial Lake Outburst Floods, Stephan Harrison, Jeffrey S. Kargel, Christian Huggel, John Reynolds, Dan H. Shugar, Richard A. Betts, Neil Glasser, Umesh K. Haritashya, Jan Klimeš, Liam Reinhardt, Yvonne Schaub, Andy Wiltshire, Dhananjay Regmi, Vít Vilímek

Geology Faculty Publications

Despite recent research identifying a clear anthropogenic impact on glacier recession, the effect of recent climate change on glacier-related hazards is at present unclear. Here we present the first global spatio-temporal assessment of glacial lake outburst floods (GLOFs) focusing explicitly on lake drainage following moraine dam failure. These floods occur as mountain glaciers recede and downwaste. GLOFs can have an enormous impact on downstream communities and infrastructure. Our assessment of GLOFs associated with the rapid drainage of moraine-dammed lakes provides insights into the historical trends of GLOFs and their distributions under current and future global climate change. We observe a …

U-Pb And Hf Isotopic Evidence For An Arctic Origin Of Terranes In Northwestern Washington, Elizabeth R. Schermer, Eric A. Hoffnagle, Edwin H. Brown, George E. Gehrels, William C. Mcclelland

Geology Faculty Publications

New field, U-Pb, and Lu-Hf zircon data constrain the geologic history, age, and origin of the Yellow Aster Complex (YAC) in northwestern Washington, providing insight into the tectonic history of this and related Paleozoic arc terranes of the western North American Cordillera. Mapping shows that the oldest YAC rocks consist of quartzofeldspathic paragneiss (meta-arkose) and quartzose calc-silicate paragneiss (metacalcareous siltstone) in gradational contact. Paragneisses are cut by syn-tectonic and post-tectonic intrusions and faulted against granitic orthogneiss. U-Pb zircon results show that (1) maximum depositional ages of paragneisses are Silurian to Early Devonian (432– 390 Ma); (2) detrital zircons from quartzose …

Biogenic Weathering: Solubilization Of Iron From Minerals By Epilithic Freshwater Algae And Cyanobacteria, George E. Mustoe

Geology Faculty Publications

A sandstone outcrop exposed to freshwater seepage supports a diverse assemblage of photosynthetic microbes. Dominant taxa are two cyanophytes (Oscillatoria sp., Rivularia sp.) and a unicellular green alga (Palmellococcus sp.). Less abundant taxa include a filamentous green alga, Microspora, and the desmid Cosmarium. Biologic activity is evidenced by measured levels of chlorophyll and lipids. Bioassay methods confirm the ability of these microbes to dissolve and metabolize Fe from ferruginous minerals. Chromatographic analysis reveals citric acid as the likely chelating agent; this low molecular weight organic acid is detectable in interstitial fluid in the sandstone, measured as …

The Recent Volcanic History Of Axial Seamount: Geophysical Insights Into Past Eruption Dynamics With An Eye Toward Enhanced Observations Of Future Eruptions, William Wilcock, Robert Dziak, Maya Tolstoy, William Chadwick, Scott Nooner, Delwayne Bohnenstiel, Jacqueline Caplan-Auerbach, Felix Waldhauser, Adrien Amulf, Christian Ballard, Tai-Kwan Lau, Joseph Haxel, Yen Joe Tan, Charles Garcia, Samuel Levy, M. Everett Mann

Geology Faculty Publications

To understand the processes that form oceanic crust as well as the role of submarine volcanoes in exchanging heat and chemicals with the ocean and in supporting chemosynthetic biological communities, it is essential to study underwater eruptions. The world’s most advanced underwater volcano observatory—the Ocean Observatories Initiative Cabled Array at Axial Seamount—builds upon ~30 years of sustained geophysical monitoring at this site with autonomous and remote systems. In April 2015, only months after the Cabled Array’s installation, it recorded an eruption at Axial Seamount, adding to the records of two prior eruptions in 1998 and 2011. Between eruptions, magma recharge …

Early Onset Of Franciscan Subduction, Sean R. Mulcahy, Jesslyn K. Starnes, Howard W. Day, Matthew A. Coble, Jeffrey D. Vervoort

Geology Faculty Publications

The Franciscan subduction complex of California is considered a type example of a subduction-accretion system, yet the age of subduction initiation and relationship to the tectonic history of western North America remain controversial. Estimates for the timing of Franciscan subduction initiation are largely based either indirectly on regional tectonic arguments or from the ages of high-grade blocks within mélange. Many of the high-grade blocks record counterclockwise pressure-temperature paths with early amphibolite overprinted by later eclogite and blueschist; however, their origin and significance with respect to subduction initiation have been debated. In contrast, some high-grade blocks show evidence for clockwise pressure-temperature …

Paleomagnetism And Rotation History Of The Blue Mountains, Oregon, Usa, Bernard A. Housen

Geology Faculty Publications

An important element in reconstructions of the Cordilleran margin of North America includes longstanding debate regarding the timing and amount of rotation of the Blue Mountains in eastern Oregon, and the origin of geometric features such as the Columbia Embayment, which was a subject of some of Bill Dickinson’s early research. Suppositions of significant clockwise rotation of the Blue Mountains derived from Dickinson’s work were confirmed in the 1980s by paleomagnetic results from Late Jurassic–Early Cretaceous plutonic rocks, and secondary directions from Permian–Triassic units of the Wallowa–Seven Devils arc that indicate ~60° clockwise rotation of the Blue Mountains.

This study …

Enhanced Recent Local Moisture Recycling On The Northwestern Tibetan Plateau Deduced From Ice Core Deuterium Excess Records, Wenling An, Shugui Hou, Qiong Zhang, Wangbin Zhang, Shuang-Ye Wu, Hao Xu, Hongxi Pang, Yetang Wang, Yaping Liu

Geology Faculty Publications

Local moisture recycling plays an essential role in maintaining an active hydrological cycle of the Tibetan Plateau (TP). Previous studies were largely limited to the seasonal time scale due to short and sparse observations, especially for the northwestern TP. In this study, we used a two‐component mixing model to estimate local moisture recycling over the past decades from the deuterium excess records of two ice cores (i.e., Chongce and Zangser Kangri) from the northwestern TP. The results show that on average almost half of the precipitation on the northwestern TP is provided by local moisture recycling. In addition, the local …

Snow Accumulation Variability Over The West Antarctic Ice Sheet Since 1900: A Comparison Of Ice Core Records With Era‐20c Reanalysis, Yetang Wang, Elizabeth R. Thomas, Shugui Hou, Baojuan Huai, Shuang-Ye Wu, Weijun Sun, Shanzhong Qi, Minghu Ding, Yulun Zhang

Geology Faculty Publications

This study uses a set of 37 firn core records over the West Antarctic Ice Sheet (WAIS) to test the performance of the twentieth century from the European Centre for Medium‐Range Weather Forecasts (ERA‐20C) reanalysis for snow accumulation and quantify temporal variability in snow accumulation since 1900. The firn cores are allocated to four geographical areas demarcated by drainage divides (i.e., Antarctic Peninsula (AP), western WAIS, central WAIS, and eastern WAIS) to calculate stacked records of regional snow accumulation. Our results show that the interannual variability in ERA‐20C precipitation minus evaporation (P − E) agrees well with the corresponding ice …

A High‐Resolution Atmospheric Dust Record For 1810–2004 A.D. Derived From An Ice Core In Eastern Tien Shan, Central Asia, Wangbin Zhang, Shugui Hou, Yaping Liu, Shuang-Ye Wu, Wenling An, Hongxi Pang, Chaomin Wang

Geology Faculty Publications

Centennial‐scale, high‐resolution records of atmospheric dust conditions are rare in the arid and semiarid regions of central Asia, limiting our understanding of the regional climate and environmental changes and their potential driving forces. In this paper, we present an annually resolved atmospheric dust record covering the period of 1810–2004 A.D., reconstructed from an ice core retrieved at 4512 m above sea level from the Miaoergou Glacier in the eastern Tien Shan. The time series of dust flux for the past 195 years shows three periods of relatively low values (i.e., 1810–1829 A.D., 1863–1940 A.D., and 1979–2004 A.D.) and two periods …

Phillipsite And Al-Tobermorite Mineral Cements Produced Through Low-Temperature Water-Rock Reactions In Roman Marine Concrete, Marie D. Jackson, Sean R. Mulcahy, Heng Chen, Yao Li, Qinfei Li, Piergiulio Cappelletti, Hans-Rudolf Wenk

Geology Faculty Publications

Pozzolanic reaction of volcanic ash with hydrated lime is thought to dominate the cementing fabric and durability of 2000-year-old Roman harbor concrete. Pliny the Elder, however, in first century CE emphasized rock-like cementitious processes involving volcanic ash (pulvis) “that as soon as it comes into contact with the waves of the sea and is submerged becomes a single stone mass (fierem unum lapidem), impregnable to the waves and every day stronger” (Naturalis Historia 35.166). Pozzolanic crystallization of Al-tobermorite, a rare, hydrothermal, calcium-silicate-hydrate mineral with cation exchange capabilities, has been previously recognized in relict lime clasts …

Explosive Processes During The 2015 Eruption Of Axial Seamount, As Recorded By Seafloor Hydrophones, Jacqueline Caplan-Auerbach, R. P. Dziak, J. Haxel, D. R. Bohnenstiehl, C. Garcia

Geology Faculty Publications

Following the installation of the Ocean Observatories Initiative cabled array, the 2015 eruption of Axial Seamount, Juan de Fuca ridge, became the first submarine eruption to be captured in real time by seafloor seismic and acoustic instruments. This eruption also marked the first instance where the entire eruption cycle of a submarine volcano, from the previous eruption in 2011 to the end of the month-long 2015 event, was monitored continuously using autonomous ocean bottom hydrophones. Impulsive sounds associated with explosive lava-water interactions are identified within hydrophone records during both eruptions. Explosions within the caldera are acoustically distinguishable from those occurring …

Impact Of Icebergs On Net Primary Productivity In The Southern Ocean, Shuang-Ye Wu, Shugui Hou

Geology Faculty Publications

Productivity in the Southern Ocean (SO) is iron-limited, and supply of iron dissolved from aeolian dust is believed to be the main source from outside the marine environment. However, recent studies show that icebergs could provide a comparable amount of bioavailable iron to the SO as aeolian dust. In addition, small-scale areal studies suggest increased concentrations of chlorophyll, krill, and seabirds surrounding icebergs. Based on previous research, this study aims to examine whether iceberg occurrence has a significant impact on marine productivity at the scale of the SO, using remote sensing data of iceberg occurrences and ocean net primary productivity …

Delayed Warming Hiatus Over The Tibetan Plateau, Wenling An, Shugui Hou, Yongyun Hu, Shuang-Ye Wu

Geology Faculty Publications

A reduction in the warming rate for the global surface temperature since the late 1990s has attracted much attention and caused a great deal of controversy. During the same time period, however, most previous studies have reported enhanced warming over the Tibetan Plateau (TP). In this study we further examined the temperature trend of the TP and surrounding areas based on the homogenized temperature records for the period 1980–2014, we found that for the TP regions lower than 4000 m the warming rate has started to slow down since the late 1990s, a similar pattern consistent with the whole China …

Phillipsite And Al-Tobermorite Mineral Cements Produced Through Low-Temperature Water-Rock Reactions In Roman Marine Concrete, Sean R. Mulcahy, Marie D. Jackson, Heng Chen, Yao Li, Piergiulio Cappelletti, Hans-Rudolf Wenk

Geology Faculty Publications

Pozzolanic reaction of volcanic ash with hydrated lime is thought to dominate the cementing fabric and durability of 2000-year-old Roman harbor concrete. Pliny the Elder, however, in first century CE emphasized rock-like cementitious processes involving volcanic ash (pulvis) “that as soon as it comes into contact with the waves of the sea and is submerged becomes a single stone mass (fierem unum lapidem), impregnable to the waves and every day stronger” (Naturalis Historia 35.166). Pozzolanic crystallization of Al-tobermorite, a rare, hydrothermal, calcium-silicate-hydrate mineral with cation exchange capabilities, has been previously recognized in relict lime clasts of the concrete. Synchrotron-based X-ray …

A Pulsed-Air Model Of Blue Whale B Call Vocalizations, R. P. Dziak, J. H. Haxel, T-K. Lau, S. Heimlich, Jacqueline Caplan-Auerbach, D. K. Mellinger, H. Matsumoto, B. Mate

Geology Faculty Publications

Blue whale sound production has been thought to occur by Helmholtz resonance via air flowing from the lungs into the upper respiratory spaces. This implies that the frequency of blue whale vocalizations might be directly proportional to the size of their sound-producing organs. Here we present a sound production mechanism where the fundamental and overtone frequencies of blue whale B calls can be well modeled using a series of short-duration (<1 >s) wavelets. We propose that the likely source of these wavelets are pneumatic pulses caused by opening and closing of respiratory valves during air recirculation between the lungs and …

Future Changes In Mean And Extreme Monsoon Precipitation In The Middle And Lower Yangtze River Basin, China, In The Cmip5 Models, Yanjuan Wu, Shuang-Ye Wu, Jiahong Wen, Felipe Tagle, Ming Xu, Jianguo Tan

Geology Faculty Publications

In this study, the potential future changes of mean and extreme precipitation in the middle and lower Yangtze River basin (MLYRB), eastern China, are assessed using the models of phase 5 of the Coupled Model Intercomparison Project (CMIP5). Historical model simulations are first compared with observations in order to evaluate model performance. In general, the models simulate the precipitation mean and frequency better than the precipitation intensity and extremes, but still have difficulty capturing precipitation patterns over complex terrains. They tend to overestimate precipitation mean, frequency, and intensity while underestimating the extremes. After correcting for model biases, the spatial variation …

Possible Recent Warming Hiatus On The Northwestern Tibetan Plateau Derived From Ice Core Records, Wenling An, Shugui Hou, Wangbin Zhang, Shuang-Ye Wu, Hao Xu, Hongxi Pang, Yetang Wang, Yaping Liu

Geology Faculty Publications

Many studies have reported enhanced warming trend on the Tibetan Plateau (TP), even during the warming hiatus period. However, most of these studies are based on instrumental data largely collected from the eastern TP, whereas the temperature trend over the extensive northwestern TP remains uncertain due to few meteorological stations. Here we combined the stable isotopic δ¹⁸O record of an ice core recovered in 2012 from the Chongce glacier with the δ¹⁸O records of two other ice cores (i.e., Muztagata and Zangser Kangri) in the same region to establish a regional temperature series for the northwestern …

Surface Slip During Large Owens Valley Fault Earthquakes, Elizabeth K. Haddon, Colin B. Amos, O. Zielke, A. S. Jayko, R. Bürgmann

Geology Faculty Publications

The 1872 Owens Valley earthquake is the third largest known historical earthquake in California. Relatively sparse field data and a complex rupture trace, however, inhibited attempts to fully resolve the slip distribution and reconcile the total moment release. We present a new, comprehensive record of surface slip based on lidar and field investigation, documenting 162 new measurements of laterally and vertically displaced landforms for 1872 and prehistoric Owens Valley earthquakes. Our lidar analysis uses a newly developed analytical tool to measure fault slip based on cross‐correlation of sublinear topographic features and to produce a uniquely shaped probability density function (PDF) …

Significant Recent Warming Over The Northern Tibetan Plateau From Ice Core Δ18o Records, W. An, S. Hou, W. Zhang, Y. Wang, Y. Liu, Shuang-Ye Wu, H. Pang

Geology Faculty Publications

Stable oxygen isotopic records in ice cores provide valuable information about past temperature, especially for regions with scarce instrumental measurements. This paper presents the δ¹⁸O result of an ice core drilled to bedrock from Mt. Zangser Kangri (ZK), a remote area on the northern Tibetan Plateau (TP). We reconstructed the temperature series for 1951–2008 from the δ¹⁸O records. In addition, we combined the ZK δ¹⁸O records with those from three other ice cores in the northern TP (Muztagata, Puruogangri, and Geladaindong) to reconstruct a regional temperature history for the period 1951–2002 (RTNTP). The RTNTP …