Transitions Between Explosive And Effusive Phases During The Cataclysmic 2010 Eruption Of Merapi Volcano, Java, Indonesia, 2019 University of East Anglia
Transitions Between Explosive And Effusive Phases During The Cataclysmic 2010 Eruption Of Merapi Volcano, Java, Indonesia, Katie Preece, Ralf Gertisser, Jenni Barclay, Sylvain J. Charbonnier, Jean-Christophe Komorowski, Richard A. Herd
Transitions between explosive and effusive activity are commonly observed during dome-forming eruptions and may be linked to factors such as magma influx, ascent rate and degassing. However, the interplay between these factors is complex and the resulting eruptive behaviour often unpredictable. This paper focuses on the driving forces behind the explosive and effusive activity during the well-documented 2010 eruption of Merapi, the volcano’s largest eruption since 1872. Time-controlled samples were collected from the 2010 deposits, linked to eruption stage and style of activity. These include scoria and pumice from the initial explosions, dense and scoriaceous dome samples formed via ...
High-Resolution Dem Generation From Multiple Remote Sensing Data Sources For Improved Volcanic Hazard Assessment - A Case Study From Nevado Del Ruiz, Colombia, Fanghui Deng, Mel Rodgers, Tim Dixon, Sylvain J. Charbonnier, Elisabeth Gallant, Nicholas Voss, Surui Xie, Rocco Malservisi, Milton Ordoñez, Cristian López
Eruptions of active volcanoes in the presence of snow and ice can cause dangerous floods, avalanches and lahars,threatening millions of people living close to such volcanoes. Colombia’s deadliest volcanic hazard in recordedhistory was caused by Nevado del Ruiz Volcano. On November 13, 1985, a relatively small eruption triggeredenormous lahars, killing over 23,000 people in the city of Armero and 2,000 people in the town of Chinchina.Meltwater from a glacier capping the summit of the volcano was the main contributor to the lahars. From 2010 topresent, increased seismicity, surface deformation, ash plumes and gas emissions have ...
Unusual Anatomy Of The Ectoparasitic Muricid Vitularia Salebrosa (King And Broderip, 1832) (Neogastropoda: Muricidae) From The Pacific Coast Of Panama, Luiz R. L. Simone, Gregory S. Herbert, Didier Merle
The morphology and anatomy of Vitularia salebrosa, a muricid ectoparasitic on other mollusks, are investigated based on study of specimens from western Panama. Distinctive characters of this species include the small size of the buccal mass and radular apparatus, simplification of the odontophore muscles and diminished lateral teeth of the radula; an elongated, narrow proboscis; narrow digestive tract and a differentiable glandular region at the beginning of the posterior esophagus. These traits are consistent with adaptive specialization for an ectoparasitic life history
Systematic Revision Of The Genus Eupleura H. And A. Adams, 1853 (Gastropoda: Muricidae) In The Neogene To Recent Of Tropical America, 2019 University of California, Davis
Systematic Revision Of The Genus Eupleura H. And A. Adams, 1853 (Gastropoda: Muricidae) In The Neogene To Recent Of Tropical America, Gregory S. Herbert
The systematics of the Neogene to Recent genus Eupleura of tropical America are revised, with descriptions of four new species: Eupleura engerrabunda, from the Late Miocene of Mexico (Atlantic); Eupleura gravidentata, from the Plio-Pleistocene of Colombia (Atlantic); Eupleura paroudia, from the Early or middle Pliocene of Mexico (Atlantic); and Eupleura vokesorum, from the Pliocene of Costa Rica (Pacific) and Ecuador and the Recent tropical eastern Pacific. Two recent taxa, Eupleura plicata and Eupleura limata, are also resurrected, increasing the standing diversity of Eupleura in the eastern Pacific to seven species. Eupleura limata, however, may have become extinct over part or ...
Extremely Slow Feeding In A Tropical Drilling Ectoparasite, Vitularia Salebrosa (King And Broderip, 1832) (Gastropoda: Muricidae), On Molluscan Hosts From Pacific Panama, 2019 University of South Florida
Extremely Slow Feeding In A Tropical Drilling Ectoparasite, Vitularia Salebrosa (King And Broderip, 1832) (Gastropoda: Muricidae), On Molluscan Hosts From Pacific Panama, Gregory S. Herbert, Gregory P. Dietl, Helena Fortunato, Luiz R. L. Simone, Jennifer Leigh Sliko
This study documents one of the slowest feeding behaviors ever recorded for a muricid gastropod in one of the most biotically rigorous regions on the planet. In Pacific Panama, Vitularia salebrosa attacks mollusks by drilling through their shells. The duration of attacks estimated by isotope sclerochronology of oyster shells collected during attacks in progress ranges from 90 to 230 days, while experimental observation of interactions documented one attack greater than 103 days. The prolonged nature of attacks suggests that V. salebrosa is best characterized as an ectoparasite than as a predator, which is the ancestral condition in the Muricidae. An ...
Did Shell-Crushing Crabs Trigger An Escalatory Arms Race In The Aftermath Of A Late Neogene Regional Mass Extinction Event? An Experimental Test, Lisa B. Whitenack, Gregory S. Herbert
A regional mass extinction event in the late Neogene western Atlantic is widely thought to have generated evolutionary opportunities for survivors, including enemy-related adaptation (escalation). The Strombus alatus species complex is one potential example of this phenomenon. Strombid gastropods are abundant in the Plio-Pleistocene fossil record and Recent in subtropical Florida, and the percentage of these shells bearing a row of short spines on the last whorl increased from nearly zero to almost 100% over this time. As shell ornamentation is one of the most frequently cited defenses against both peeling and crushing predators, we exposed live spined and spineless ...
A Large New Species Of Lobatus (Gastropoda: Stromnidae) From The Neogene Of The Dominican Republic, With Notes On The Genus, Bernard M. Landau, Gijs C. Kronenberg, Gregory S. Herbert
No abstract provided.
Social Impacts Of Citizen Science Water Monitoring Programs, 2019 Iowa State University
Social Impacts Of Citizen Science Water Monitoring Programs, Nancy Grudens-Schuck, Zulham Sirajuddin
The drive to protect and improve surface water quality requires an array of policies, institutions, professionals, and procedures, even in the face of uncertain budgets and an increasing scope of work. Since the 1990s, the concept of “citizen science” has provided a framework under which volunteers supplement the water monitoring duties of scientists by producing more data and, in some cases, expanding their reach (Conrad and Hinchey 2011; McKinley et al. 2017). Volunteers, on the whole, benefit by contributing to society (Lawrence 2006), and by learning about science and environmental issues (Hecker et al. 2018; McKinley et al. 2017; Phillips ...
The Geotraces Intermediate Data Product 2014, 2019 The GEOTRACES Group
The Geotraces Intermediate Data Product 2014, Tim M. Conway
Tim M Conway
The GEOTRACES Intermediate Data Product 2014 (IDP2014) is the first publicly available data product of the international GEOTRACES programme, and contains data measured and quality controlled before the end of 2013. It consists of two parts: (1) a compilation of digital data for more than 200 trace elements and isotopes (TEIs) as well as classical hydrographic parameters, and (2) the eGEOTRACES Electronic Atlas providing a strongly inter-linked on-line atlas including more than 300 section plots and 90 animated 3D scenes. The IDP2014 covers the Atlantic, Arctic, and Indian oceans, exhibiting highest data density in the Atlantic. The TEI data in ...
The Acceleration Of Dissolved Cobalt's Ecological Stoichiometry Due To Biological Uptake, Remineralization, And Scavenging In The Atlantic Ocean, 2019 Woods Hole Oceanographic Institution
The Acceleration Of Dissolved Cobalt's Ecological Stoichiometry Due To Biological Uptake, Remineralization, And Scavenging In The Atlantic Ocean, Mak A. Saito, Abagail E. Noble, Nicholas Hawco, Benjamin S. Twining, Daniel C. Ohnemus, Seth G. John, Phoebe Lam, Tim M. Conway, Rod Johnson, Dawn Moran, Matthew Mcilvin
Tim M Conway
The stoichiometry of biological components and their influence on dissolved distributions have long been of interest in the study of the oceans. Cobalt has the smallest oceanic inventory of inorganic micronutrients and hence is particularly vulnerable to influence by internal oceanic processes including euphotic zone uptake, remineralization, and scavenging. Here we observe not only large variations in dCo:P stoichiometry but also the acceleration of those dCo:P ratios in the upper water column in response to several environmental processes. The ecological stoichiometry of total dissolved cobalt (dCo) was examined using data from a US North Atlantic GEOTRACES transect and ...
The Biogeochemical Cycling Of Zinc And Zinc Isotopes In The North Atlantic Ocean, 2019 University of South Carolina
The Biogeochemical Cycling Of Zinc And Zinc Isotopes In The North Atlantic Ocean, Tim M. Conway, Seth G. John
Tim M Conway
Zinc (Zn) is a marine micronutrient, with an overall oceanic distribution mirroring the major macronutrients, especially silicate. Seawater Zn isotope ratios (δ66Zn) are a relatively new oceanographic parameter which may offer insights into the biogeochemical cycling of Zn. To date, the handful of published studies of seawater δ66Zn show the global deep ocean to be both remarkably homogeneous (approximately +0.5‰) and isotopically heavier than the marine sources of Zn (+0.1 to +0.3‰). Here we present the first high‐resolution oceanic section of δ66Zn, from the U.S. GEOTRACES GA03 North Atlantic ...
The Geotraces Intermediate Data Product 2017, 2019 ConwayGEOTRACES
The Geotraces Intermediate Data Product 2017, Tim M. Conway
Tim M Conway
The GEOTRACES Intermediate Data Product 2017 (IDP2017) is the second publicly available data product of the international GEOTRACES programme, and contains data measured and quality controlled before the end of 2016. The IDP2017 includes data from the Atlantic, Pacific, Arctic, Southern and Indian oceans, with about twice the data volume of the previous IDP2014. For the first time, the IDP2017 contains data for a large suite of biogeochemical parameters as well as aerosol and rain data characterising atmospheric trace element and isotope (TEI) sources. The TEI data in the IDP2017 are quality controlled by careful assessment of intercalibration results and ...
Inter-Calibration Of A Proposed New Primary Reference Standard Aa-Eth Zn For Zinc Isotopic Analysis, Corey Archer, Morten B. Anderson, Christophe Cloquet, Tim M. Conway, Shoufei Dong, Michael Ellwood, Rebekah Moore, Joey Nelson, Mark Rehkamper
Tim M Conway
We have prepared a large volume of pure, concentrated and homogenous zinc standard solution. This new standard solution is intended to be used as a primary reference standard for the zinc isotope community, and to serve as a replacement for the nearly exhausted current reference standard, the so-called JMC-Lyon Zn. The isotopic composition of this new zinc standard (AA-ETH Zn) has been determined through an inter-laboratory calibration exercise, calibrated against the existing JMC-Lyon standard, as well as the certified Zn reference standard IRMM-3702. The data show that the new standard is isotopically indistinguishable from the IRMM-3702 zinc standard, with a ...
Constraints On Soluble Aerosol Iron Flux To The Southern Ocean At The Last Glacial Maximum, 2019 University of Cambridge
Constraints On Soluble Aerosol Iron Flux To The Southern Ocean At The Last Glacial Maximum, Tim M. Conway, E. W. Wolff, R. Röthlisberger, R. Mulvaney, H. E. Elderfield
Tim M Conway
Relief of iron (Fe) limitation in the Southern Ocean during ice ages, with potentially increased carbon storage in the ocean, has been invoked as one driver of glacial–interglacial atmospheric CO2 cycles. Ice and marine sediment records demonstrate that atmospheric dust supply to the oceans increased by up to an order of magnitude during glacial intervals. However, poor constraints on soluble atmospheric Fe fluxes to the oceans limit assessment of the role of Fe in glacial–interglacial change. Here, using novel techniques, we present estimates of water- and seawater-soluble Fe solubility in Last Glacial Maximum (LGM) atmospheric dust from ...
Distinct Iron Isotopic Signatures And Supply From Marine Sediment Dissolution, 2019 University of Southampton
Distinct Iron Isotopic Signatures And Supply From Marine Sediment Dissolution, William B. Homoky, Seth G. John, Tim M. Conway, Rachel A. Mills
Tim M Conway
Oceanic iron inputs must be traced and quantified to learn how they affect primary productivity and climate. Chemical reduction of iron in continental margin sediments provides a substantial dissolved flux to the oceans, which is isotopically lighter than the crust, and so may be distinguished in seawater from other sources, such as wind-blown dust. However, heavy iron isotopes measured in seawater have recently led to the proposition of another source of dissolved iron from ‘non-reductive’ dissolution of continental margins. Here we present the first pore water iron isotope data from a passive-tectonic and semi-arid ocean margin (South Africa), which reveals ...
Shoreline Dynamics Along A Developed River Mouth Barrier Island: Multi-Decadal Cycles Of Erosion And Event-Driven Mitigation, 2019 Virginia Institute of Marine Science
Shoreline Dynamics Along A Developed River Mouth Barrier Island: Multi-Decadal Cycles Of Erosion And Event-Driven Mitigation, Christopher J. Hein, Andrrew R. Fallon, Peter Rosen, Et Al
Human modifications in response to erosion have altered the natural transport of sediment to and across the coastal zone, thereby potentially exacerbating the impacts of future erosive events. Using a combination of historical shoreline-change mapping, sediment sampling, three-dimensional beach surveys, and hydrodynamic modeling of nearshore and inlet processes, this study explored the feedbacks between periodic coastal erosion patterns and associated mitigation responses, focusing on the open-ocean and inner-inlet beaches of Plum Island and the Merrimack River Inlet, Massachusetts, United States. Installation of river-mouth jetties in the early 20th century stabilized the inlet, allowing residential development in northern Plum Island, but ...
Fluid Transport In Porous Media For Engineering Applications, 2019 University of New Mexico
Fluid Transport In Porous Media For Engineering Applications, Eric M. Benner
Chemical and Biological Engineering ETDs
This doctoral dissertation presents three topics in modeling fluid transport through porous media used in engineering applications. The results provide insights into the design of fuel cell components, catalyst and drug delivery particles, and aluminum- based materials. Analytical and computational methods are utilized for the modeling of the systems of interest. Theoretical analysis of capillary-driven transport in porous media show that both geometric and evaporation effects significantly change the time dependent behavior of liquid imbibition and give a steady state flux into the medium. The evaporation–capillary number is significant in determining the time-dependent behavior of capillary flows in porous ...
Glacial Meltwater Modeling To Simulate Streamflow And Lake Levels In Taylor Valley, Antarctica, 2019 Portland State University
Glacial Meltwater Modeling To Simulate Streamflow And Lake Levels In Taylor Valley, Antarctica, Julian M. Cross, Andrew G. Fountain
Student Research Symposium
The McMurdo Dry Valleys (MDV) are the largest ice-free region (4,500 km2) in Antarctica. The MDV are a polar desert with an average annual temperature of -18˚C and minimal precipitation, < 50 mm w.e. a-1. In Taylor Valley (77°35’ S, 163°00’ E), a closed-basin, perennially ice-covered lakes occupy the valley floor. Ephemeral streams transfer glacier meltwater for ~10 weeks each summer. Glacial meltwater accounts for nearly the total inflow to these streams and lakes, groundwater is essentially non-existent. A microbially-dominated ecosystem in Taylor Valley depends on glacier runoff and thus is highly sensitive to changes to the hydroclimatic regime ...
Early Onset Of Franciscan Subduction, 2019 Western Washington University
Early Onset Of Franciscan Subduction, Sean R. Mulcahy, Jesslyn K. Starnes, Howard W. Day, Matthew A. Coble, Jeffrey D. Vervoort
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 ...
Subduction Initiation And Early Evolution Of The Easton Metamorphic Suite, Northwest Cascades, Washington, 2019 Western Washington University
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
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 ...