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Full-Text Articles in Geological Engineering

Characterizing Soil Stiffness Using Thermal Remote Sensing And Machine Learning, Jordan Ewing, T. Oommen, Paramsothy Jayakumar, Russell Alger Jun 2021

Characterizing Soil Stiffness Using Thermal Remote Sensing And Machine Learning, Jordan Ewing, T. Oommen, Paramsothy Jayakumar, Russell Alger

Michigan Tech Publications

Soil strength characterization is essential for any problem that deals with geomechanics, including terramechanics/terrain mobility. Presently, the primary method of collecting soil strength parameters through in situ measurements but sending a team of people out to a site to collect data this has significant cost implications and accessing the location with the necessary equipment can be difficult. Remote sensing provides an alternate approach to in situ measurements. In this lab study, we compare the use of Apparent Thermal Inertia (ATI) against a GeoGauge for the direct testing of soil stiffness. ATI correlates with stiffness, so it allows one to predict …


Potentials Of Airborne Hyperspectral Aviris-Ng Data In The Exploration Of Base Metal Deposit—A Study In The Parts Of Bhilwara, Rajasthan, Arindam Guha, Uday Kumar Ghosh, Joyasree Sinha, Amin Beiranvand Pour, Ratnakar Bhaisal, Snehamoy Chatterjee, Nikhil Kumar Baranval, Nisha Rani, K. Vinod Kumar, Pamaraju V.N. Rao May 2021

Potentials Of Airborne Hyperspectral Aviris-Ng Data In The Exploration Of Base Metal Deposit—A Study In The Parts Of Bhilwara, Rajasthan, Arindam Guha, Uday Kumar Ghosh, Joyasree Sinha, Amin Beiranvand Pour, Ratnakar Bhaisal, Snehamoy Chatterjee, Nikhil Kumar Baranval, Nisha Rani, K. Vinod Kumar, Pamaraju V.N. Rao

Michigan Tech Publications

In this study, we have processed the spectral bands of airborne hyperspectral data of Advanced Visible Infrared Imaging Spectrometer-Next Generation (AVIRIS-NG) data for delineating the surface signatures associated with the base metal mineralization in the Pur-Banera area in the Bhilwara district, Rajasthan, India.The primaryhost rocks of the Cu, Pb, Zn mineralization in the area are Banded Magnetite Quartzite (BMQ), unclassified calcareous silicates, and quartzite. We used ratio images derived from the scale and root mean squares (RMS) error imagesusing the multi-range spectral feature fitting (MRSFF) methodto delineate host rocks from the AVIRIS-NG image. The False Color Composites (FCCs) of different …


Global Health Effects Of Future Atmospheric Mercury Emissions, Yanxu Zhang, Zhengcheng Song, Shaojian Huang, Peng Zhang, Yiming Peng, Peipei Wu, Jing Gu, Stephanie Dutkiewicz, Huanxin Zhang, Shiliang Wu, Feiyue Wang, Long Chen, Shuxiao Wang, Ping Li May 2021

Global Health Effects Of Future Atmospheric Mercury Emissions, Yanxu Zhang, Zhengcheng Song, Shaojian Huang, Peng Zhang, Yiming Peng, Peipei Wu, Jing Gu, Stephanie Dutkiewicz, Huanxin Zhang, Shiliang Wu, Feiyue Wang, Long Chen, Shuxiao Wang, Ping Li

Michigan Tech Publications

Mercury is a potent neurotoxin that poses health risks to the global population. Anthropogenic mercury emissions to the atmosphere are projected to decrease in the future due to enhanced policy efforts such as the Minamata Convention, a legally-binding international treaty entered into force in 2017. Here, we report the development of a comprehensive climate-atmosphere-land-ocean-ecosystem and exposure-risk model framework for mercury and its application to project the health effects of future atmospheric emissions. Our results show that the accumulated health effects associated with mercury exposure during 2010–2050 are $19 (95% confidence interval: 4.7–54) trillion (2020 USD) realized to 2050 (3% discount …


Calculation Of Real Evapotranspiration By The Application Of Metric Method On Landsat-8 Data, Ali Imanian, Majid Hashemi Tangestani, Adel Asadi, Mohammad Zare Jan 2021

Calculation Of Real Evapotranspiration By The Application Of Metric Method On Landsat-8 Data, Ali Imanian, Majid Hashemi Tangestani, Adel Asadi, Mohammad Zare

Michigan Tech Publications

In geological remote sensing approaches for estimating evapotranspiration, METRIC method is among the most modern and precise approaches that many positive experiments have been reported regarding its applicability. In this study, the value of actual evapotranspiration (ET) occurred in Marvdasht farmlands, Fars province, Iran, was calculated instantaneously (hourly) and daily (24 hours), at 24 April 2017 using METRIC method and Lansat-8 data. In order to accuracy assessment of the results, estimated values were compared to the values calculated with Penman Monteith method in places that covers by alfafa crop. Our observations showed that ET values obtained via METRIC model on …


Effect Of Spectral Bandwidths On Linear Feature Extraction: An Evaluation Of Landsat Etm+ And Oli Sensors, Ali Imanian, Adel Asadi, Majid Hashemi Tangestani, Saeid Homayouni, Ali Faghih Jan 2021

Effect Of Spectral Bandwidths On Linear Feature Extraction: An Evaluation Of Landsat Etm+ And Oli Sensors, Ali Imanian, Adel Asadi, Majid Hashemi Tangestani, Saeid Homayouni, Ali Faghih

Michigan Tech Publications

Hitherto there have been many studies comparing the usefulness of OLI and ETM+ sensors for linear feature extraction. However, not too much attention has been paid to the differences in the bandwidth of the two sensors. In this study, the suitability of Landsat ETM+ and OLI sensors for automatic detection of linear features by LINE algorithm was compared. In this study, eight regions in northern, central and southern parts of Iran were selected based on the diversity of lithology, the pristine status, and lack of human activities for the comparison of the two datasets. Results revealed that LINE algorithm performed …


Version 2 Ozone Monitoring Instrument So2 Product (Omso2 V2): New Anthropogenic So2 Vertical Column Density Dataset, Can Li, Nickolay A. Krotkov, Peter J.T. Leonard, Simon Carn, Joanna Joiner, Robert J.D. Spurr, Alexander Vasilkov Nov 2020

Version 2 Ozone Monitoring Instrument So2 Product (Omso2 V2): New Anthropogenic So2 Vertical Column Density Dataset, Can Li, Nickolay A. Krotkov, Peter J.T. Leonard, Simon Carn, Joanna Joiner, Robert J.D. Spurr, Alexander Vasilkov

Michigan Tech Publications

The Ozone Monitoring Instrument (OMI) has been providing global observations of SO2 pollution since 2004. Here we introduce the new anthropogenic SO2 vertical column density (VCD) dataset in the version 2 OMI SO2 product (OMSO2 V2). As with the previous version (OMSO2 V1.3), the new dataset is generated with an algorithm based on principal component analysis of OMI radiances but features several updates. The most important among those is the use of expanded lookup tables and model a priori profiles to estimate SO2 Jacobians for individual OMI pixels, in order to better characterize pixel-to-pixel variations in SO2 sensitivity including over …


Constructing A Complete Landslide Inventory Dataset For The 2018 Monsoon Disaster In Kerala, India, For Land Use Change Analysis, Lina Hao, Rajaneesh A., Cees Van Westen, Sajinkumar K. S., Tapas Ranjan Martha, Pankaj Jaiswal, Brian G. Mcadoo Nov 2020

Constructing A Complete Landslide Inventory Dataset For The 2018 Monsoon Disaster In Kerala, India, For Land Use Change Analysis, Lina Hao, Rajaneesh A., Cees Van Westen, Sajinkumar K. S., Tapas Ranjan Martha, Pankaj Jaiswal, Brian G. Mcadoo

Michigan Tech Publications

Event-based landslide inventories are important for analyzing the relationship between the intensity of the trigger (e.g., rainfall, earthquake) and the density of the landslides in a particular area as a basis for the estimation of the landslide probability and the conversion of susceptibility maps into hazard maps required for risk assessment. They are also crucial for the establishment of local rainfall thresholds that are the basis of early warning systems and for evaluating which land use and land cover changes are related to landslide occurrence. The completeness and accuracy of event-based landslide inventories are crucial aspects to derive reliable results …


Using Tandem-X To Measure Pyroclastic Flow Source Location, Thickness And Volume: Application To The 3rd June 2018 Eruption Of Fuego Volcano, Guatemala, F. Albino, J. Biggs, R. Escobar-Wolf, A. Naismith, M. Watson, J. C. Phillips, G. A. Chigna Marroquin Nov 2020

Using Tandem-X To Measure Pyroclastic Flow Source Location, Thickness And Volume: Application To The 3rd June 2018 Eruption Of Fuego Volcano, Guatemala, F. Albino, J. Biggs, R. Escobar-Wolf, A. Naismith, M. Watson, J. C. Phillips, G. A. Chigna Marroquin

Michigan Tech Publications

The estimation of the volume of volcanic flows during an ongoing eruption is challenging but this information is crucial for improving risk assessment and for forecasting future events. Although previous studies have shown the ability of TanDEM-X satellite data to derive the thickness and the volume of lava flow fields during effusive eruptions, the method has not been explored yet for pyroclastic flows. Using bi-static interferometry, we produce TanDEM-X DEM on Fuego volcano (Guatemala) to measure the significant topographic changes caused by the 3rd June 2018 eruption, which destroyed the town of San Miguel Los Lotes. We estimate the volume …


Effect Of Geometry And Fluid Viscosity On Dynamics Of Fluid-Filled Cracks: Insights From Analog Experimental Observations, Haitao Cao, Ezequiel F. Medici, Gregory P. Waite, Roohollah Askari Nov 2020

Effect Of Geometry And Fluid Viscosity On Dynamics Of Fluid-Filled Cracks: Insights From Analog Experimental Observations, Haitao Cao, Ezequiel F. Medici, Gregory P. Waite, Roohollah Askari

Michigan Tech Publications

Fluid-filled volumes in geological systems can change the local stress field in the host rock and may induce brittle deformation as well as crack propagation. Although the mechanisms relating fluid pressure perturbations and seismicity have been widely studied, the fluid-solid interaction inside the crack of a host rock is still not well understood. An analog experimental model of fluid intrusion in cracks between planar layers has been developed to study stress conditions at the margins and tips. A combined high-speed shadowgraph and a photoelasticity imaging system is used to visualize the fluid dynamics and induced stresses on the solid matrix. …


Design And Development Of A Machine Vision System Using Artificial Neural Network-Based Algorithm For Automated Coal Characterization, Amit Kumar Gorai, Simit Raval, Ashok Kumar Patel, Snehamoy Chatterjee, Tarini Gautam Oct 2020

Design And Development Of A Machine Vision System Using Artificial Neural Network-Based Algorithm For Automated Coal Characterization, Amit Kumar Gorai, Simit Raval, Ashok Kumar Patel, Snehamoy Chatterjee, Tarini Gautam

Michigan Tech Publications

Coal is heterogeneous in nature, and thus the characterization of coal is essential before its use for a specific purpose. Thus, the current study aims to develop a machine vision system for automated coal characterizations. The model was calibrated using 80 image samples that are captured for different coal samples in different angles. All the images were captured in RGB color space and converted into five other color spaces (HSI, CMYK, Lab, xyz, Gray) for feature extraction. The intensity component image of HSI color space was further transformed into four frequency components (discrete cosine transform, discrete wavelet transform, discrete Fourier …


Global Aeolian Dust Variations And Trends: A Revisit Of Dust Event And Visibility Observations From Surface Weather Stations, Xin Xi Oct 2020

Global Aeolian Dust Variations And Trends: A Revisit Of Dust Event And Visibility Observations From Surface Weather Stations, Xin Xi

Michigan Tech Publications

This study revisits the use of horizontal visibility and manually reported present weather (ww) records from the NOAA Integrated Surface Database (ISD) for characterizing the aeolian dust variability and recent trends over the globe and three largest source regions (North Africa, Middle East, and East Asia). Due to its qualitative nature, ww is combined with visibility to derive a new variable, VI, which has higher correlations with the dust emission and burden from satellite observations and global aerosol reanalyses than does the dust event frequency (FR) derived from ww only. Both FR and VI capture …


Utilizing Hyperspectral Remote Sensing For Soil Gradation, Jordan Ewing, T. Oommen, Paramsothy Jayakumar, Russell Alger Oct 2020

Utilizing Hyperspectral Remote Sensing For Soil Gradation, Jordan Ewing, T. Oommen, Paramsothy Jayakumar, Russell Alger

Michigan Tech Publications

Soil gradation is an important characteristic for soil mechanics. Traditionally soil gradation is performed by sieve analysis using a sample from the field. In this research, we are interested in the application of hyperspectral remote sensing to characterize soil gradation. The specific objective of this work is to explore the application of hyperspectral remote sensing to be used as an alternative to traditional soil gradation estimation. The advantage of such an approach is that it would provide the soil gradation without having to obtain a field sample. This work will examine five different soil types from the Keweenaw Research Center …


Flow Simulation Considering Adsorption Boundary Layer Based On Digital Rock And Finite Element Method, Yong Fei Yang, Ke Wang, Qian Fei Lv, Roohollah Askari, Qing Yan Mei, Jun Yao, Jie Xin Hou, Kai Zhang, Ai Fen Li, Chen Chen Wang Jun 2020

Flow Simulation Considering Adsorption Boundary Layer Based On Digital Rock And Finite Element Method, Yong Fei Yang, Ke Wang, Qian Fei Lv, Roohollah Askari, Qing Yan Mei, Jun Yao, Jie Xin Hou, Kai Zhang, Ai Fen Li, Chen Chen Wang

Michigan Tech Publications

Due to the low permeability of tight reservoirs, throats play a significant role in controlling fluid flow. Although many studies have been conducted to investigate fluid flow in throats in the microscale domain, comparatively fewer works have been devoted to study the effect of adsorption boundary layer (ABL) in throats based on the digital rock method. By considering an ABL, we investigate its effects on fluid flow. We build digital rock model based on computed tomography technology. Then, microscopic pore structures are extracted with watershed segmentation and pore geometries are meshed through Delaunay triangulation approach. Finally, using the meshed digital …


Paleomagnetic Evidence For Modern-Like Plate Motion Velocities At 3.2 Ga, Alec R. Brenner, Roger R. Fu, David A.D. Evans, Aleksey V. Smirnov, Raisa Trubko, Ian R. Rose Apr 2020

Paleomagnetic Evidence For Modern-Like Plate Motion Velocities At 3.2 Ga, Alec R. Brenner, Roger R. Fu, David A.D. Evans, Aleksey V. Smirnov, Raisa Trubko, Ian R. Rose

Michigan Tech Publications

The mode and rates of tectonic processes and lithospheric growth during the Archean [4.0 to 2.5 billion years (Ga) ago] are subjects of considerable debate. Paleomagnetism may contribute to the discussion by quantifying past plate velocities. We report a paleomagnetic pole for the ~3180 million year (Ma) old Honeyeater Basalt of the East Pilbara Craton, Western Australia, supported by a positive fold test and micromagnetic imaging. Comparison of the 44°±15° Honeyeater Basalt paleolatitude with previously reported paleolatitudes requires that the average latitudinal drift rate of the East Pilbara was ≥2.5 cm/year during the ~170 Ma preceding 3180 Ma ago, a …


A New Discrete Wavelength Backscattered Ultraviolet Algorithm For Consistent Volcanic So2 Retrievals From Multiple Satellite Missions, Bradford L. Fisher, Nickolay A. Krotkov, Pawan K. Bhartia, Can Li, Simon Carn, Eric Hughes, Peter J. T. Leonard Sep 2019

A New Discrete Wavelength Backscattered Ultraviolet Algorithm For Consistent Volcanic So2 Retrievals From Multiple Satellite Missions, Bradford L. Fisher, Nickolay A. Krotkov, Pawan K. Bhartia, Can Li, Simon Carn, Eric Hughes, Peter J. T. Leonard

Michigan Tech Publications

This paper describes a new discrete wavelength algorithm developed for retrieving volcanic sulfur dioxide (SO2) vertical column density (VCD) from UV observing satellites. The Multi-Satellite SO2 algorithm (MS_SO2) simultaneously retrieves column densities of sulfur dioxide, ozone, and Lambertian effective reflectivity (LER) and its spectral dependence. It is used operationally to process measurements from the heritage Total Ozone Mapping Spectrometer (TOMS) onboard NASA's Nimbus-7 satellite (N7/TOMS: 1978–1993) and from the current Earth Polychromatic Imaging Camera (EPIC) onboard Deep Space Climate Observatory (DSCOVR: 2015–ongoing) from the Earth–Sun Lagrange (L1) orbit. Results from MS_SO2 algorithm for several volcanic cases were …


Volcano Monitoring From Space Using High-Cadence Planet Cubesat Images Applied To Fuego Volcano, Guatemala, Anna Aldeghi, Simon Carn, Rudiger Escobar-Wolf, Gianluca Groppelli Sep 2019

Volcano Monitoring From Space Using High-Cadence Planet Cubesat Images Applied To Fuego Volcano, Guatemala, Anna Aldeghi, Simon Carn, Rudiger Escobar-Wolf, Gianluca Groppelli

Michigan Tech Publications

Fuego volcano (Guatemala) is one of the most active and hazardous volcanoes in the world. Its persistent activity generates lava flows, pyroclastic density currents (PDCs), and lahars that threaten the surrounding areas and produce frequent morphological change. Fuego’s eruption deposits are often rapidly eroded or remobilized by heavy rains and its constant activity and inaccessible terrain makes ground-based assessment of recent eruptive deposits very challenging. Earth-orbiting satellites can provide unique observations of volcanoes during eruptive activity, when ground-based techniques may be too hazardous, and also during inter-eruptive phases, but have typically been hindered by relatively low spatial and temporal resolution. …


Analysis Of An Updated Paleointensity Database (Qpi‐Pint) For 65–200 Ma: Implications For The Long‐Term History Of Dipole Moment Through The Mesozoic, E. V. Kulakov, C. J. Sprain, P. V. Doubrovine, A. V. Smirnov, G. A. Paterson, L. Hawkins, L. Fairchild, E. J. Piispa, A. J. Biggin Sep 2019

Analysis Of An Updated Paleointensity Database (Qpi‐Pint) For 65–200 Ma: Implications For The Long‐Term History Of Dipole Moment Through The Mesozoic, E. V. Kulakov, C. J. Sprain, P. V. Doubrovine, A. V. Smirnov, G. A. Paterson, L. Hawkins, L. Fairchild, E. J. Piispa, A. J. Biggin

Michigan Tech Publications

The global paleointensity database for 65–200 Ma was analyzed using a modified suite of paleointensity quality criteria (QPI) such that the likely reliability of measurements is assessed objectively and as consistently as possible across the diverse data set. This interval was chosen because of dramatic extremes of geomagnetic polarity reversal frequency ranging from greater than 10 reversals per million years in the Jurassic hyperactivity period (155–171 Ma) to effectively zero during the Cretaceous Normal Superchron (CNS; 84–126 Ma). Various attempts to establish a relationship between the strength of Earth's magnetic field and the reversal frequency have been made …


Thermal Conduction Simulation Based On Reconstruction Digital Rocks With Respect To Fractures, Haiyuan Yang, Li Zhang, Ronghe Liu, Xianli Wen, Yongfei Yang, Roohollah Askari, Et. Al. Jul 2019

Thermal Conduction Simulation Based On Reconstruction Digital Rocks With Respect To Fractures, Haiyuan Yang, Li Zhang, Ronghe Liu, Xianli Wen, Yongfei Yang, Roohollah Askari, Et. Al.

Michigan Tech Publications

Effective thermal conductivity (ETC), as a necessary parameter in the thermal properties of rock, is affected by the pore structure and the thermal conduction conditions. To evaluate the effect of fractures and saturated fluids on sandstone’s thermal conductivity, we simulated thermal conduction along three orthogonal (X, Y, and Z) directions under air- and water-saturated conditions on reconstructed digital rocks with different fractures. The results show that the temperature distribution is separated by the fracture. The significant difference between the thermal conductivities of solid and fluid is the primary factor influencing the temperature distribution, and the thermal conduction mainly depends on …


Emittance Spectroscopy And Broadband Thermal Remote Sensing Applied To Phosphorite And Its Utility In Geoexploration: A Study In The Parts Of Rajasthan, India, Arindam Guha, Yasushi Yamaguchi, Snehamoy Chatterjee, Komai Rani, Kumranchat Vinod Kumar Apr 2019

Emittance Spectroscopy And Broadband Thermal Remote Sensing Applied To Phosphorite And Its Utility In Geoexploration: A Study In The Parts Of Rajasthan, India, Arindam Guha, Yasushi Yamaguchi, Snehamoy Chatterjee, Komai Rani, Kumranchat Vinod Kumar

Michigan Tech Publications

The contrast in the emissivity spectra of phosphorite and associated carbonate rock can be used as a guide to delineate phosphorite within dolomite. The thermal emissivity spectrum of phosphorite is characterized by a strong doublet emissivity feature with their absorption minima at 9 µm and 9.5 µm; whereas, host rock dolomite has relatively subdued emissivity minima at ~9 µm. Using the contrast in the emissivity spectra of phosphorite and dolomite, data obtained by the thermal bands of Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) sensor were processed to delineate phosphorite within dolomite. A decorrelation stretched ASTER radiance composite could …


Evidence Of Instability In Previously-Mapped Landslides As Measured Using Gps, Optical, And Sar Data Between 2007 And 2017: A Case Study In The Portuguese Bend Landslide Complex, California, El Hachemi Y. Bouali, Thomas Oommen, Rüdiger Escobar-Wolf Apr 2019

Evidence Of Instability In Previously-Mapped Landslides As Measured Using Gps, Optical, And Sar Data Between 2007 And 2017: A Case Study In The Portuguese Bend Landslide Complex, California, El Hachemi Y. Bouali, Thomas Oommen, Rüdiger Escobar-Wolf

Michigan Tech Publications

Velocity dictates the destructive potential of a landslide. A combination of synthetic aperture radar (SAR), optical, and GPS data were used to maximize spatial and temporal coverage to monitor continuously-moving portions of the Portuguese Bend landslide complex on the Palos Verdes Peninsula in Southern California. Forty SAR images from the COSMO-SkyMed satellite, acquired between 19 July 2012 and 27 September 2014, were processed using Persistent Scatterer Interferometry (PSI). Eight optical images from the WorldView-2 satellite, acquired between 20 February 2011 and 16 February 2016, were processed using the Co-registration of Optically Sensed Images and Correlation (COSI-Corr) technique. Displacement measurements were …


Climbing The Crustal Ladder: Magma Storage-Depth Evolution During A Volcanic Flare-Up, Guilherme A. R. Gualda, Darren M. Gravley, Michelle Connor, Brooke Hollmann, Ayla S. Pamukcu, Florence Begue, Mark S. Ghiorso, Chad Deering Oct 2018

Climbing The Crustal Ladder: Magma Storage-Depth Evolution During A Volcanic Flare-Up, Guilherme A. R. Gualda, Darren M. Gravley, Michelle Connor, Brooke Hollmann, Ayla S. Pamukcu, Florence Begue, Mark S. Ghiorso, Chad Deering

Michigan Tech Publications

Very large eruptions (>50 km3) and supereruptions (>450 km3) reveal Earth’s capacity to produce and store enormous quantities (>1000 km3) of crystal-poor, eruptible magma in the shallow crust. We explore the interplay between crustal evolution and volcanism during a volcanic flare-up in the Taupo Volcanic Zone (TVZ, New Zealand) using a combination of quartz-feldspar-melt equilibration pressures and time scales of quartz crystallization. Over the course of the flare-up, crystallization depths became progressively shallower, showing the gradual conditioning of the crust. Yet, quartz crystallization times were invariably very short (<100 years), demonstrating that very large reservoirs of eruptible magma were transient crustal features. We conclude that the dynamic nature of the TVZ crust favored magma eruption over storage. Episodic tapping of eruptible magmas likely prevented a supereruption. Instead, multiple very large bodies of eruptible magma were assembled and erupted in decadal time scales.


Landsliding Near Enguri Dam (Caucasus, Georgia) And Possible Seismoectonic Effects, Alessandro Tibaldi, Paolo Oppizzi, John S. Gierke, Thomas Oommen, Nino Tsereteli, Davit Odilavadze Aug 2018

Landsliding Near Enguri Dam (Caucasus, Georgia) And Possible Seismoectonic Effects, Alessandro Tibaldi, Paolo Oppizzi, John S. Gierke, Thomas Oommen, Nino Tsereteli, Davit Odilavadze

Michigan Tech Publications

The Enguri dam and water reservoir, nested in southwestern Caucasus (Republic of Georgia), are surrounded by steep mountain slopes. At a distance of 2.5 km from the dam, a mountain ridge along the reservoir is affected by active deformations with a double vergence. The western slope, directly facing the reservoir, has deformations that involve a subaerial area of 1.2 km2. The head scarp interests the main Jvari-Khaishi-Mestia road with offset of man-made features that indicate slip rates of 2-9 cm/y. Static, pseudostatic and Newmark numerical analyses, based on field and seismological data, suggest different unstable rock volumes basing on the …


Slalom: An All-Surface Snow Water Path Retrieval Algorithm For The Gpm Microwave Imager, Jean-François Rysman, Giulia Panegrossi, Paolo Sanò, Anna Cinzia Marra, Stefano Dietrich, Lisa Milani, Mark S. Kulie Aug 2018

Slalom: An All-Surface Snow Water Path Retrieval Algorithm For The Gpm Microwave Imager, Jean-François Rysman, Giulia Panegrossi, Paolo Sanò, Anna Cinzia Marra, Stefano Dietrich, Lisa Milani, Mark S. Kulie

Michigan Tech Publications

This paper describes a new algorithm that is able to detect snowfall and retrieve the associated snow water path (SWP), for any surface type, using the Global Precipitation Measurement (GPM) Microwave Imager (GMI). The algorithm is tuned and evaluated against coincident observations of the Cloud Profiling Radar (CPR) onboard CloudSat. It is composed of three modules for (i) snowfall detection, (ii) supercooled droplet detection and (iii) SWP retrieval. This algorithm takes into account environmental conditions to retrieve SWP and does not rely on any surface classification scheme. The snowfall detection module is able to detect 83% of snowfall events including …


Sensitivity Of Atmospheric Aerosol Scavenging To Precipitation Intensity And Frequency In The Context Of Global Climate Change, Pei Hou, Shiliang Wu, Jessica L. Mccarty, Yang Gao Jun 2018

Sensitivity Of Atmospheric Aerosol Scavenging To Precipitation Intensity And Frequency In The Context Of Global Climate Change, Pei Hou, Shiliang Wu, Jessica L. Mccarty, Yang Gao

Michigan Tech Publications

Wet deposition driven by precipitation is an important sink for atmospheric aerosols and soluble gases. We investigate the sensitivity of atmospheric aerosol lifetimes to precipitation intensity and frequency in the context of global climate change. Our sensitivity model simulations, through some simplified perturbations to precipitation in the GEOS-Chem model, show that the removal efficiency and hence the atmospheric lifetime of aerosols have significantly higher sensitivities to precipitation frequencies than to precipitation intensities, indicating that the same amount of precipitation may lead to different removal efficiencies of atmospheric aerosols. Combining the long-term trends of precipitation patterns for various regions with the …


The Ozone Monitoring Instrument: Overview Of 14 Years In Space, Pieternel F. Levelt, Joanna Joiner, Johanna Tamminen, J. Pepijn Veefkind, Pawan K. Bhartia, Simon Carn, Et. Al. Apr 2018

The Ozone Monitoring Instrument: Overview Of 14 Years In Space, Pieternel F. Levelt, Joanna Joiner, Johanna Tamminen, J. Pepijn Veefkind, Pawan K. Bhartia, Simon Carn, Et. Al.

Michigan Tech Publications

This overview paper highlights the successes of the Ozone Monitoring Instrument (OMI) on board the Aura satellite spanning a period of nearly 14 years. Data from OMI has been used in a wide range of applications and research resulting in many new findings. Due to its unprecedented spatial resolution, in combination with daily global coverage, OMI plays a unique role in measuring trace gases important for the ozone layer, air quality, and climate change. With the operational very fast delivery (VFD; direct readout) and near real-time (NRT) availability of the data, OMI also plays an important role in the development …


Early Warning System For Shallow Landslides Using Rainfall Threshold And Slope Stability Analysis, Shruti Naidu, K. S. Sajinkumar, Thomas Oommen, V.J. Anuja, Rinu Samuel, C. Muraleedharan Oct 2017

Early Warning System For Shallow Landslides Using Rainfall Threshold And Slope Stability Analysis, Shruti Naidu, K. S. Sajinkumar, Thomas Oommen, V.J. Anuja, Rinu Samuel, C. Muraleedharan

Michigan Tech Publications

A combined cluster and regression analysis were performed for the first time to identify rainfall threshold that triggers landslide events in Amboori, Kerala, India. Amboori is a tropical area that is highly vulnerable to landslides. The 2, 3, and 5-day antecedent rainfall data versus daily rainfall was clustered to identify a cluster of critical events that could potentially trigger landslides. Further, the cluster of critical events was utilized for regression analysis to develop the threshold equations. The 5-day antecedent (x-variable) vs. daily rainfall (y-variable) provided the best fit to the data with a threshold equation of …


Atmospheric Processes Affecting The Separation Of Volcanic Ash And So < Inf> 2 In Volcanic Eruptions: Inferences From The May 2011 Grímsvötn Eruption, Fred Prata, Mark Woodhouse, Herbert E. Huppert, Andrew Prata, Thor Thordarson, S. Carn Sep 2017

Atmospheric Processes Affecting The Separation Of Volcanic Ash And So < Inf> 2 In Volcanic Eruptions: Inferences From The May 2011 Grímsvötn Eruption, Fred Prata, Mark Woodhouse, Herbert E. Huppert, Andrew Prata, Thor Thordarson, S. Carn

Michigan Tech Publications

The separation of volcanic ash and sulfur dioxide (SO2) gas is sometimes observed during volcanic eruptions. The exact conditions under which separation occurs are not fully understood but the phenomenon is of importance because of the effects volcanic emissions have on aviation, on the environment, and on the earth's radiation balance. The eruption of Grímsvötn, a subglacial volcano under the Vatnajökull glacier in Iceland during 21-28 May 2011 produced one of the most spectacular examples of ash and SO2 separation, which led to errors in the forecasting of ash in the atmosphere over northern Europe. Satellite data from several sources …


A Novel Applications Of Photogrammetry For Retaining Wall Assessment, Renee Oats, Rudiger Escobar-Wolf, Thomas Oommen Aug 2017

A Novel Applications Of Photogrammetry For Retaining Wall Assessment, Renee Oats, Rudiger Escobar-Wolf, Thomas Oommen

Michigan Tech Publications

Retaining walls are critical geotechnical assets and their performance needs to be monitored in accordance to transportation asset management principles. Current practices for retaining wall monitoring consist mostly of qualitative approaches that provide limited engineering information or the methods include traditional geodetic surveying, which may provide high accuracy and reliability, but is costly and time-consuming. This study focuses on evaluating failure modes of a 2.43 m × 2.43 m retaining wall model using three-dimensional (3D) photogrammetry as a cost-effective quantitative alternative for retaining wall monitoring. As a remote sensing technique, photogrammetry integrates images collected from a camera and creates a …


Expanding Understanding Of Optical Variability In Lake Superior With A 4-Year Dataset, Colleen B. Mouw, Audrey B. Ciochetto, Brice Grunert, Angela W. Yu Jul 2017

Expanding Understanding Of Optical Variability In Lake Superior With A 4-Year Dataset, Colleen B. Mouw, Audrey B. Ciochetto, Brice Grunert, Angela W. Yu

Michigan Tech Publications

Lake Superior is one of the largest freshwater lakes on our planet, but few optical observations have been made to allow for the development and validation of visible spectral satellite remote sensing products. The dataset described here focuses on coincidently observing inherent and apparent optical properties along with biogeochemical parameters. Specifically, we observe remote sensing reflectance, absorption, scattering, backscattering, attenuation, chlorophyll concentration, and suspended particulate matter over the ice-free months of 2013-2016. The dataset substantially increases the optical knowledge of the lake. In addition to visible spectral satellite algorithm development, the dataset is valuable for characterizing the variable light field, …


Spatial Variability Of Co < Inf> 2 Uptake In Polygonal Tundra: Assessing Low-Frequency Disturbances In Eddy Covariance Flux Estimates, Norbert Pirk, Jakob Sievers, Jordan Mertes, Frans Jan W. Parmentier, Mikhail Mastepanov, Torben R. Christensen Jun 2017

Spatial Variability Of Co < Inf> 2 Uptake In Polygonal Tundra: Assessing Low-Frequency Disturbances In Eddy Covariance Flux Estimates, Norbert Pirk, Jakob Sievers, Jordan Mertes, Frans Jan W. Parmentier, Mikhail Mastepanov, Torben R. Christensen

Michigan Tech Publications

The large spatial variability in Arctic tundra complicates the representative assessment of CO2 budgets. Accurate measurements of these heterogeneous landscapes are, however, essential to understanding their vulnerability to climate change. We surveyed a polygonal tundra lowland on Svalbard with an unmanned aerial vehicle (UAV) that mapped ice-wedge morphology to complement eddy covariance (EC) flux measurements of CO2. The analysis of spectral distributions showed that conventional EC methods do not accurately capture the turbulent CO2 exchange with a spatially heterogeneous surface that typically features small flux magnitudes. Nonlocal (low-frequency) flux contributions were especially pronounced during snowmelt and introduced a large bias …