Geology Commons^™

Sampling Bias In Evaluating The Probability Of Seismically Induced Soil Liquefaction With Spt & Cpt Case Histories, Abhishek Jain

Dissertations, Master's Theses and Master's Reports - Open

Several deterministic and probabilistic methods are used to evaluate the probability of seismically induced liquefaction of a soil. The probabilistic models usually possess some uncertainty in that model and uncertainties in the parameters used to develop that model. These model uncertainties vary from one statistical model to another. Most of the model uncertainties are epistemic, and can be addressed through appropriate knowledge of the statistical model. One such epistemic model uncertainty in evaluating liquefaction potential using a probabilistic model such as logistic regression is sampling bias. Sampling bias is the difference between the class distribution in the sample used for …

Using Auto- And Cross-Correlations From Seismic Noise To Monitor Velocity Changes At Villarrica Volcano, Chile, Kathleen F. Mckee

Dissertations, Master's Theses and Master's Reports - Open

We used the Green's functions from auto-correlations and cross-correlations of seismic ambient noise to monitor temporal velocity changes in the subsurface at Villarrica volcano in the Southern Andes of Chile. Campaigns were conducted from March to October 2010 and February to April 2011 with 8 broadband and 6 short-period stations, respectively. We prepared the data by removing the instrument response, normalizing with a root-mean-square method, whitening the spectra, and filtering from 1 to 10 Hz. This frequency band was chosen based on the relatively high background noise level in that range. Hour-long auto- and cross-correlations were computed and the Green's …

Comparing Satellite And Ground-Based Observations Of Paroxysmal Degassing Events At Etna Volcano, Italy, Céline L. Mandon

Dissertations, Master's Theses and Master's Reports - Open

Mount Etna, Italy, is one of the most active volcanoes in the world, and is also regarded as one of the strongest volcanic sources of sulfur dioxide (SO₂) emissions to the atmosphere. Since October 2004, an automated ultraviolet (UV) spectrometer network (FLAME) has provided ground-based SO₂ measurements with high temporal resolution, providing an opportunity to validate satellite SO₂ measurements at Etna. The Ozone Monitoring Instrument (OMI) on the NASA Aura satellite, which makes global daily measurements of trace gases in the atmosphere, was used to compare SO₂ amount released by the volcano during paroxysmal lava-fountaining …

Slope Stability Analysis Of The Pacaya Volcano, Guatemala, Using Limit Equilibrium And Finite Element Method , Patrick. Manzoni

Dissertations, Master's Theses and Master's Reports - Open

The Pacaya volcanic complex is part of the Central American volcanic arc, which is associated with the subduction of the Cocos tectonic plate under the Caribbean plate. Located 30 km south of Guatemala City, Pacaya is situated on the southern rim of the Amatitlan Caldera. It is the largest post-caldera volcano, and has been one of Central America’s most active volcanoes over the last 500 years. Between 400 and 2000 years B.P, the Pacaya volcano had experienced a huge collapse, which resulted in the formation of horseshoe-shaped scarp that is still visible. In the recent years, several smaller collapses have …

Geotechnical Data And Numerical Analysis Of Edifice Collapse And Related Hazards At Pacaya Volcano, Guatemala, Lauren N. Schaefer

Dissertations, Master's Theses and Master's Reports - Open

The continual eruptive activity, occurrence of an ancestral catastrophic collapse, and inherent geologic features of Pacaya volcano (Guatemala) demands an evaluation of potential collapse hazards. This thesis merges techniques in the field and laboratory for a better rock mass characterization of volcanic slopes and slope stability evaluation. New field geological, structural, rock mechanical and geotechnical data on Pacaya is reported and is integrated with laboratory tests to better define the physical-mechanical rock mass properties. Additionally, this data is used in numerical models for the quantitative evaluation of lateral instability of large sector collapses and shallow landslides. Regional tectonics and local …

Vulnerability Of High Latitude Soil Organic Carbon In North America To Disturbance, Guido Grosse, Jennifer Harden, Merritt Turetsky, David A. Mcguire, Philip Camill, Charles Tarnocai, Steve Frolking, Edward A.G. Schuur, Torre Jorgenson, Sergei Marchenko, Vladimir Romanovsky, Kimberly P. Wickland, Nancy H. F. French, Mark Waldrop, Laura Bourgeau-Chavez, Robert G. Striegl

Michigan Tech Research Institute Publications

This synthesis addresses the vulnerability of the North American high-latitude soil organic carbon (SOC) pool to climate change. Disturbances caused by climate warming in arctic, subarctic, and boreal environments can result in significant redistribution of C among major reservoirs with potential global impacts. We divide the current northern high-latitude SOC pools into (1) near-surface soils where SOC is affected by seasonal freeze-thaw processes and changes in moisture status, and (2) deeper permafrost and peatland strata down to several tens of meters depth where SOC is usually not affected by short-term changes. We address key factors (permafrost, vegetation, hydrology, paleoenvironmental history) …

Lineament Mapping For Groundwater Exploration Using Remotely Sensed Imagery In A Karst Terrain : Rio Tanama And Rio De Arecibo Basins In The Northern Karst Of Puerto Rico, Carla A. Alonso-Contes

Dissertations, Master's Theses and Master's Reports - Open

Remote sensing and advanced digital image processing techniques were developed and tested for delineating karst features important for the subterranean hydrology in the Tanamá River and Rio Grande de Arecibo catchments located in the North Coast Tertiary Basin of Puerto Rico, where groundwater contributes to base flow for surface water bodies which in itself is the main supply of drinking water. This aquifer region is a karst platform of carbonate rocks and clastic beds, thought to comprise a confined aquifer beneath and an unconfined aquifer. Products derived from ASTER, Landsat (ETM+ and TM), a NED DEM (30 m), and a …

Characterization Of Harmonic Tremor At Santiaguito Volcano And Its Implications For Eruption Mechanisms , Kyle Arthur Brill

Dissertations, Master's Theses and Master's Reports - Open

We observed Santiaguito volcano in southwestern Guatemala from March 2008 - March 2010. Seismic and infrasound data collected between January and March of 2009 contain records of many diverse processes occurring at the dacitic dome complex, including the recurrence of short lived (30-200 seconds in duration) harmonic tremor concurrent with ash poor gas emissions from the volcano. We employ several different analytical techniques to examine different portions of the tremor and source mechanisms. We use the parameters derived by this analysis to compare the feasibility of several suggested models of eruption mechanisms, and determine that this type of harmonic tremor …

Sonic Log Prediction In Carbonates , Nayyer Islam

Dissertations, Master's Theses and Master's Reports - Open

This work is conducted to study the complications associated with the sonic log prediction in carbonate logs and to investigate the possible solutions to accurately predict the sonic logs in Traverse Limestone. Well logs from fifty different wells were analyzed to define the mineralogy of the Traverse Limestone by using conventional 4-mineral and 3-mineral identification approaches. We modified the conventional 3-mineral identification approach (that completely neglects the gamma ray response) to correct the shale effects on the basis of gamma ray log before employing the 3-mineral identification. This modification helped to get the meaningful insight of the data when a …

Comparisons Between Omi So2 Data And Ground-Based So2 Measurements At Turrialba Volcano , Anieri M. Morales Rivera

Dissertations, Master's Theses and Master's Reports - Open

Turrialba is one of the largest and most active stratovolcanoes in the Central Cordillera of Costa Rica and an excellent target for validation of satellite data using ground based measurements due to its high elevation, relative ease of access, and persistent elevated SO₂ degassing. The Ozone Monitoring Instrument (OMI) aboard the Aura satellite makes daily global observations of atmospheric trace gases and it is used in this investigation to obtain volcanic SO₂ retrievals in the Turrialba volcanic plume. We present and evaluate the relative accuracy of two OMI SO₂ data analysis procedures, the automatic Band Residual Index …

Ultraviolet Digital Imaging Of Volcanic Plumes : Implementation And Application To Magmatic Processes At Basaltic Volcanoes, Patricia Amanda Nadeau

Dissertations, Master's Theses and Master's Reports - Open

Magmatic volatiles play a crucial role in volcanism, from magma production at depth to generation of seismic phenomena to control of eruption style. Accordingly, many models of volcano dynamics rely heavily on behavior of such volatiles. Yet measurements of emission rates of volcanic gases have historically been limited, which has restricted model verification to processes on the order of days or longer.

UV cameras are a recent advancement in the field of remote sensing of volcanic SO₂ emissions. They offer enhanced temporal and spatial resolution over previous measurement techniques, but need development before they can be widely adopted and …

Recurrent Voluminous Sector Collapses At Volcán Barú, Panama, Julie A. Herrick

Dissertations, Master's Theses and Master's Reports - Open

Two volcanic debris avalanche deposits (VDADs), both attributed to sector collapse at Volcán Barú, Panama, have been identified after an investigation of deposits that covered more than a thousand square kilometers. The younger Barriles Deposit is constrained by two radiocarbon ages that are ~9 ka; the older Caisán Deposit is at or beyond the radiocarbon range, >43,500 ybp. The total runout length of the Caisán Deposit was ~50 km and it covers 1190 km². The Barriles Deposit extended to about 45 km and covered an area of 966 km², overlapping most of the Caisán. The VDADs …

Using Water Balance Models To Approximate The Effects Of Climate Change On Spring Catchment Discharge : Mt. Hanang, Tanzania , Randall E. Fish

Dissertations, Master's Theses and Master's Reports - Open

This project addresses the potential impacts of changing climate on dry-season water storage and discharge from a small, mountain catchment in Tanzania. Villagers and water managers around the catchment have experienced worsening water scarcity and attribute it to increasing population and demand, but very little has been done to understand the physical characteristics and hydrological behavior of the spring catchment. The physical nature of the aquifer was characterized and water balance models were calibrated to discharge observations so as to be able to explore relative changes in aquifer storage resulting from climate changes.

To characterize the shallow aquifer supplying water …

"The Need Obliged Us" : Culture As Capacity During The Hurricane Stan Emergency Response. A Case Study From Tectitan, Huehuetenango, Guatemala , Jesse Silverman

Dissertations, Master's Theses and Master's Reports - Open

A major deficiency in disaster management plans is the assumption that pre-disaster civil-society does not have the capacity to respond effectively during crises. Following from this assumption a dominant emergency management strategy is to replace weak civil-society organizations with specialized disaster organizations that are often either military or Para-military and seek to centralize decision-making. Many criticisms have been made of this approach, but few specifically addresses disasters in the developing world. Disasters in the developing world present unique problems not seen in the developed world because they often occur in the context of compromised governments, and marginalized populations. In this …

Estimation Of Vertical Groundwater Fluxes Into A Streambed Through Continuous Temperature Profile Monitoring And The Relationship Of Groundwater Fluxes To Coaster Brook Trout Spawning Habitat , Matthew Van Grinsven

Dissertations, Master's Theses and Master's Reports - Open

We hypothesized that the spatial distribution of groundwater inflows through river bottom sediments is a critical factor associated with the selection of coaster brook trout (a life history variant of Salvelinus fontinalis,) spawning sites. An 80-m reach of the Salmon Trout River, in the Huron Mountains of the upper peninsula of Michigan, was selected to test the hypothesis based on long-term documentation of coaster brook trout spawning at this site. Throughout this site, the river is relatively similar along its length with regard to stream channel and substrate features. A monitoring well system consisting of an array of 27 …

Simulating Dioxane Transport In A Heterogeneous Glacial Aquifer System (Washtenaw County, Michigan) Using Publicly Available Models And Data, Rungroj Benjakul

Dissertations, Master's Theses and Master's Reports - Open

The primary challenge in groundwater and contaminant transport modeling is obtaining the data needed for constructing, calibrating and testing the models. Large amounts of data are necessary for describing the hydrostratigraphy in areas with complex geology. Increasingly states are making spatial data available that can be used for input to groundwater flow models. The appropriateness of this data for large-scale flow systems has not been tested. This study focuses on modeling a plume of 1,4-dioxane in a heterogeneous aquifer system in Scio Township, Washtenaw County, Michigan. The analysis consisted of: (1) characterization of hydrogeology of the area and construction of …

Differential Gps As A Monitoring Tool On Volcano Santa Ana (Illamatepec) And The Coatepeque Caldera, El Salvador, Hans N. Lechner

Dissertations, Master's Theses and Master's Reports - Open

We used differential GPS measurements from a 13 station GPS network spanning the Santa Ana Volcano and Coatepeque Caldera to characterize the inter-eruptive activity and tectonic movements near these two active and potentially hazardous features. Caldera-forming events occurred from 70-40 ka and at Santa Ana/Izalco volcanoes eruptive activity occurred as recently as 2005. Twelve differential stations were surveyed for 1 to 2 hours on a monthly basis from February through September 2009 and tied to a centrally located continuous GPS station, which serves as the reference site for this volcanic network. Repeatabilities of the averages from 20-minute sessions taken over …

La Yeguada Volcanic Complex, Western Panama : An Assessment Of The Geologic Hazards Using New 40Ar/39Ar Ages, Karinne L. Knutsen

Dissertations, Master's Theses and Master's Reports - Open

La Yeguada volcanic complex is one of three Quaternary volcanic centers in Panama, and is located on the southern slope of the Cordillera Central mountain range in western Panama, province of Veraguas. To assess potential geologic hazards, this study focused on the main dome complex near the village of La Laguna and also examined a cinder cone 10 km to the northwest next to the village of Media Luna. Based on newly obtained ⁴⁰Ar/³⁹Ar ages, the most recent eruption occurred approximately 32 000 years ago at the Media Luna cinder cone, while the youngest dated eruption at …

Hydrometeor-Enhanced Tephra Sedimentation: Constraints From The 18 May 1980 Eruption Of Mount St. Helens, Adam J. Durant, William I. Rose, A. M. Sarna-Wojcicki, S. Carey, A. C. M. Volentik

Department of Geological and Mining Engineering and Sciences Publications

Uncertainty remains on the origin of distal mass deposition maxima observed in many recent tephra fall deposits. In this study the link between ash aggregation and the formation of distal mass deposition maxima is investigated through reanalysis of tephra fallout from the Mount St. Helens 18 May 1980 (MSH80) eruption. In addition, we collate all the data needed to model distal ash sedimentation from the MSH80 eruption cloud. Four particle size subpopulations were present in distal fallout with modes at 2.2 Φ, 4.2 Φ, 5.9 Φ, and 8.3 Φ. Settling rates of the coarsest subpopulation closely matched predicted single-particle terminal …

Ice Nucleation And Overseeding Of Ice In Volcanic Clouds, Adam J. Durant, R. A. Shaw, William I. Rose, Y. Mi, G. G. J. Ernst

Department of Geological and Mining Engineering and Sciences Publications

Water is the dominant component of volcanic gas emissions, and water phase transformations, including the formation of ice, can be significant in the dynamics of volcanic clouds. The effectiveness of volcanic ash particles as ice-forming nuclei (IN) is poorly understood and the sparse data that exist for volcanic ash IN have been interpreted in the context of meteorological, rather than volcanic clouds. In this study, single-particle freezing experiments were carried out to investigate the effect of ash particle composition and surface area on water drop freezing temperature. Measured freezing temperatures show only weak correlations with ash IN composition and surface …

Manual Pumping Test Method For Characterizing The Productivity Of Drilled Wells Equipped With Rope Pumps, Essa L. Gross

Dissertations, Master's Theses and Master's Reports - Open

Since the introduction of the rope-pump in Nicaragua in the 1990s, the dependence on wells in rural areas has grown steadily. However, little or no attention is paid to rope-pump well performance after installation. Due to financial restraints, groundwater resource monitoring using conventional testing methods is too costly and out of reach of rural municipalities. Nonetheless, there is widespread agreement that without a way to quantify the changes in well performance over time, prioritizing regulatory actions is impossible. A manual pumping test method is presented, which at a fraction of the cost of a conventional pumping test, measures the specific …

Erupted Magma Volume Estimates At Santiaguito And Pacaya Volcanoes, Guatemala Using Digital Elevation Models , Kelly S. Durst

Dissertations, Master's Theses and Master's Reports - Open

High resolution digital elevation models (DEMs) of Santiaguito and Pacaya volcanoes, Guatemala, were used to estimate volume changes and eruption rates between 1954 and 2001. The DEMs were generated from contour maps and aerial photography, which were analyzed in ArcGIS 9.0®. Because both volcanoes were growing substantially over the five decade period, they provide a good data set for exploring effective methodology for estimating volume changes. The analysis shows that the Santiaguito dome complex grew by 0.78 ± 0.07 km³ (0.52 ± 0.05 m³ s^-1) over the 1954-2001 period with nearly all the growth occurring on …

Digital Processing And Data Compilation Approach For Using Remotely Sensed Imagery To Identify Geological Lineaments In Hard-Rock Terrains : An Application For Groundwater Explorations In Nicaragua , Jill N. Bruning

Dissertations, Master's Theses and Master's Reports - Open

Sustainable yields from water wells in hard-rock aquifers are achieved when the well bore intersects fracture networks. Fracture networks are often not readily discernable at the surface. Lineament analysis using remotely sensed satellite imagery has been employed to identify surface expressions of fracturing, and a variety of image-analysis techniques have been successfully applied in “ideal” settings. An ideal setting for lineament detection is where the influences of human development, vegetation, and climatic situations are minimal and hydrogeological conditions and geologic structure are known. There is not yet a well-accepted protocol for mapping lineaments nor have different approaches been compared in …

Evolution Of The Southern Kenya Rift From Miocene To Present With A Focus On The Magadi Area, Alexandria L. Guth

Dissertations, Master's Theses and Master's Reports - Open

The Kenya (a.k.a., Gregory) Rift is a geologically active area located within the eastern branch of the larger East African Rift System (EARS). The study area is located in the southern Kenya Rift between 1° South and the Kenya-Tanzania border (covering approximately 1.5 square degrees, semi-centered on Lake Magadi) and is predominantly filled with extrusive igneous rocks (mostly basalts, phonolites and trachytes) of Miocene age or younger. Sediments are thin, less than 1.5Ma, and are confined to small grabens. The EARS can serve both as an analogue for ancient continental rifting and as a modern laboratory to observe the geologic …

Paleoenvironmental Reconstructions From Cave Sediments Of The Moravian Karst, Czech Republic / By Pavel Sroubek., Pavel Sroubek

Dissertations, Master's Theses and Master's Reports - Open

This thesis presents a paleoclimatic/paleoenvironmental study conducted on clastic cave sediments of the Moravian Karst, Czech Republic. The study is based on environmental magnetic techniques, yet a wide range of other scientific methods was used to obtain a clearer picture of the Quaternary climate. My thesis also presents an overview of the significance of cave deposits for paleoclimatic reconstructions, explains basic environmental magnetic techniques and offers background information on the study area – a famous karst region in Central Europe with a rich history.

In Kulna Cave magnetic susceptibility variations and in particular variations in pedogenic susceptibility yield a detailed …

Atmospheric Chemistry Of A 33–34 Hour Old Volcanic Cloud From Hekla Volcano (Iceland): Insights From Direct Sampling And The Application Of Chemical Box Modeling, William I. Rose, Genevieve A. Millard, Tamsin A. Mather, Donald E. Hunton, Bruce Anderson, Clive Oppenheimer, Brett F. Thornton, Terrence M. Gerlach, Albert A. Viggiano, Yutaka Kondo, Thomas M. Miller, John O. Ballenthin

Department of Geological and Mining Engineering and Sciences Publications

On 28 February 2000, a volcanic cloud from Hekla volcano, Iceland, was serendipitously sampled by a DC-8 research aircraft during the SAGE III Ozone Loss and Validation Experiment (SOLVE I). It was encountered at night at 10.4 km above sea level (in the lower stratosphere) and 33–34 hours after emission. The cloud is readily identified by abundant SO2 (≤1 ppmv), HCl (≤70 ppbv), HF (≤60 ppbv), and particles (which may have included fine silicate ash). We compare observed and modeled cloud compositions to understand its chemical evolution. Abundances of sulfur and halogen species indicate some oxidation of sulfur gases but …

Halogen Emissions From A Small Volcanic Eruption: Modeling The Peak Concentrations, Dispersion, And Volcanically Induced Ozone Loss In The Stratosphere, G. A. Millard, T. A. Mather, D. M. Pyle, William I. Rose, B. Thornton

Department of Geological and Mining Engineering and Sciences Publications

Aircraft measurements in the Hekla, Iceland volcanic plume in February 2000 revealed large quantities of hydrogen halides within the stratosphere correlated to volcanic SO2. Investigation of the longer-term stratospheric impact of these emissions, using the 3D chemical transport model, SLIMCAT suggests that volcanic enhancements of H2O and HNO3 increased HNO3·3H2O particle availability within the plume. These particles activated volcanic HCl and HBr, enhancing model plume concentrations of ClOx (20 ppb) and BrOx (50 ppt). Model O3 concentrations decreased to near-zero in places, and plume average O3 remained 30% lower after two weeks. Reductions in the model O3column reduced UV shielding …

Effects Of Carbonation On The Mineral Composition Of Cement Kiln Dust, Cecilia P. Anderson

Dissertations, Master's Theses and Master's Reports - Open

Due to their relatively high calcium oxide content, industrial mineral oxide wastes are potential candidates for mineral sequestration of carbon dioxide (CO₂). Cement kiln dust (CKD), a byproduct of cement manufacturing contains 20-60% CaO making it a possible candidate for CO₂ sequestration. In this study, three types of CKD are characterized, before and after carbonation, using environmental scanning electron microscopy and energy dispersive x-ray microanalysis to determine the mineralogical and morphological changes occurring due to carbonation. The reactants, products, and precipitation mechanisms were investigated to enhance understanding of the governing processes and allow better utilization of CKD …

Carbon Dioxide Sequestration In Cement Kiln Dust Through Miner Carbonation, Deborah N. Huntzinger

Dissertations, Master's Theses and Master's Reports - Open

The feasibility of carbon sequestration in cement kiln dust (CKD) was investigated in a series of batch and column experiments conducted under ambient temperature and pressure conditions. The significance of this work is the demonstration that alkaline wastes, such as CKD, are highly reactive with carbon dioxide (CO₂). In the presence of water, CKD can sequester greater than 80% of its theoretical capacity for carbon without any amendments or modifications to the waste. Other mineral carbonation technologies for carbon sequestration rely on the use of mined mineral feedstocks as the source of oxides. The mining, pre-processing and reaction …

Analyzing The Effects Of Vertical Acceleration And Deceleration In Multi-Phase, Debris-Flow Sediment-Column Experiments / By Christine Marie Williams., Christine Marie Williams

Dissertations, Master's Theses and Master's Reports - Open

Water-saturated debris flows are among some of the most destructive mass movements. Their complex nature presents a challenge for quantitative description and modeling. In order to improve understanding of the dynamics of these flows, it is important to seek a simplified dynamic system underlying their behavior. Models currently in use to describe the motion of debris flows employ depth-averaged equations of motion, typically assuming negligible effects from vertical acceleration. However, in many cases debris flows experience significant vertical acceleration as they move across irregular surfaces, and it has been proposed that friction associated with vertical forces and liquefaction merit inclusion …