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Construction Aspects And Seismic Analysis Of Typical Buildings In Dolpo, Lhakpa Tsering

Independent Study Project (ISP) Collection

This study delves into the construction aspects and seismic analysis of typical buildings in the challenging terrain of Dolpo, situated within the Himalayan mountain range. Dolpo's unique geological and geographical characteristics, combined with its susceptibility to seismic activity, make it crucial to investigate and understand the dynamics of construction in this remote region. The research explores traditional and contemporary building practices, aiming to elucidate the interplay between construction methodologies and seismic resilience. Through a comprehensive examination of the geological context, structural design, and seismic vulnerability, this study contributes valuable insights to inform the development of robust and earthquake-resistant building strategies …

Understanding The Role Of The Jet Streams And Gulf Stream Eddies On The Northwest Atlantic Marine Heatwaves, Lydia Rose Duncan Sims

Theses and Dissertations

The Northwest (NW) Atlantic is one of the fastest warming regions in the global ocean and in the recent decade has experienced several extreme temperature events. These extreme anomalous temperature events are known as Marine Heatwaves (MHWs), which are forced by a variety of physical processes that affect the heat source and sink of the water column. These MHWs have been increasing globally in duration and frequency due to anthropogenic warming, and have increased ecological damage seen in mass mortality events of economically viable species. Within the NW Atlantic, several key processes encourage the formation of MHWs, such as the …

Poor Water Quality Persists In Diverse Urban Communities, Rae Cade, Danlin Yu, Kyle Whyte, Pankaj Lal, Cortni Borgerson

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

While humans need water to survive, water can also efficiently transmit microbial diseases and heavy metals to consumers. Over 50,000 water violations occurred in 2020 and such burdens were not borne equally amongst consumers. Yet, the factors that drive such variation remain unclear. We examined the interactions between water quality and inherited equity gaps in one of the most diverse urban areas in the United States. We used publicly available drinking water datasets to determine which contaminant was most prevalent between 2010–2020 and who was significantly more likely to be affected by this contamination. We found that a lack of …

A New View Of Chlorophyll Dynamics In The Southern Mid-Atlantic Bight From A Two-Year High-Resolution Spray Glider Survey, Francesco Lane

OES Theses and Dissertations

The southern Mid-Atlantic Bight (MAB) near Cape Hatteras, NC, USA, is likely a hotspot for the episodic export of carbon-rich shelf waters to the open ocean. Over a 2 year period, from March 2017 to May 2019, Spray gliders repeatedly occupied transects, along the slope and across the shelf, generating high-resolution chlorophyll fluorescence (fChl) data in the southern MAB. This study implements an fChl calibration method utilizing remotely sensing ocean color as a standard. We validate the method’s utility by demonstrating a reduction in post-calibration cross-mission fChl variability and demonstrating close correspondence between the calibrated fChl data and an in …

An Effective Model For Dynamic Properties Of Local Soils And Their Influence On Seismic Response Of A Typical Reinforced Concrete Building, Kaveh Zehtab

Civil & Environmental Engineering Theses & Dissertations

This dissertation presents an effective model to determine the dynamic properties of local soils and their impact on the seismic response of a typical mid-height reinforced concrete building. The results of the study suggest that the use of global models and empirical relationships for the dynamic properties of soils may not consider the effects of unique stress conditions on the cyclic response of the foundation soil. The study also investigates the seismic response of a site in central Adapazarı, Turkey, where four- to seven-story buildings suffered significant damage during the 1999 Kocaeli earthquake. A new model is presented that combines …

Temperate Silvopastures Provide Greater Ecosystem Services Than Conventional Pasture Systems, Helen C.S. Amorim, Amanda Ashworth, Peter L. O'Brien, Andrew L. Thomas, Benjamin R. Runkle, Dirk Philipp

Crop, Soil and Environmental Sciences Faculty Publications and Presentations

Management and design affect systems’ ability to deliver ecosystem services and meet sustainable intensification needs for a growing population. Soil–plant–animal health evaluations at the systems level for conventional and silvopastoral environments are lacking and challenge adoption across temperate regions. Impacts of silvopasture on soil quality, microclimate, cattle heat stress, forage quality and yield, and cattle weight gain were compared to a conventional pasture in the mid-southern US. Here, we illustrate silvopastures have greater soil organic carbon, water content, and overall quality, with lower temperatures (soil and cattle) than conventional pastures. Forage production and cattle weight gains were similar across systems; …

Mineralogy And Geochemical Characteristics Of Matamba Kaolin Deposit-Njombe Region South-Western Tanzania: Implications For Industrial Applications, Melania A. Nyimbo, Ronald J. Massawe, Michael M. Msabi

Tanzania Journal of Science

Kaolin is a commercial clay material composed of hydrated aluminosilicate mineral kaolinite and used in various industrial applications such as ceramics, paper, paints, refractories, fiberglass, plastics, cosmetics and pharmaceuticals. It is formed as a result of strong chemical weathering of crystalline and feldspar-rich rocks or hydrothermal alteration of granitic rocks at relatively low temperature and pressure conditions. The kaolin deposit of Matamba originated from the weathering of leucogabbro rock during the development of the African land surface. In view of highlighted properties, the mineralogy and chemical characteristics of the Matamba kaolin deposit were investigated to determine its industrial applications. As …

Public Perceptions Of Water Quality In The Lake Bunyonyi Sub-Catchment, Western Uganda, Alex Saturday, Thomas J. Lyimo, Siajali Pamba, Susan Kangume, Jeniffer Turyatemba

Tanzania Journal of Science

Lake Bunyonyi ecosystem plays vital roles in water resource conservancy and tourism. Nevertheless, the rapid increase in human population and the unrelenting human activities are threatening the values, functions, and ecological integrity of the lake. In this study, the public perceptions of drinking water quality and its health implications in the Lake Bunyonyi Sub-catchment, Western Uganda are presented. A closed-ended questionnaire was administered to 267 respondents living within one Kilometre away from the lake shores. Besides, observation and interview methods were used to complement data collected by the questionnaire method. Results indicate that the prominent activities around the lake are …

Wind Speed Forecasting Using Wavelet Analysis And Recurrent Artificial Neural Networks Based On Local Measurements In Singida Region, Tanzania, Rajabu J. Mangara, Mwingereza J. Kumwenda

Tanzania Journal of Science

High accuracy wind speed forecasting is essential for wind energy harvest and plays a significant role in wind farm management and grid integration. Wind speed is intermittent in nature, which makes the forecasting to be a big challenge. In the present study, three hybrid single-step wind speed forecasting techniques are proposed and tested by local measurement data in Singida region, Tanzania. The three techniques are based on Wavelet Analysis (WA), Back Propagation (BP) optimization algorithm, and Recurrent Neural Network (RNN). They are referred to as WA-RNN, BP-RNN, and WA-BP-RNN. The model results showed that WA-BP-RNN outperforms the other two proposed …

Isotope And Hydrochemical Characteristics Of Thermal Waters Along The Active Fault Zone (Erzin-Hatay/Turkey) And Their Geothermal Potential, Di̇dem Yasi̇n, Gali̇p Yüce

Turkish Journal of Earth Sciences

Geochemical investigations carried out on thermal waters over the Erzin-Hatay area allowed the collection of a suite of 9 samples from natural springs and one well characterized by outlet temperatures in the range from 19.6 to 31.5 °C. All of the springs have slightly acidic pH (in the range of 6) but one sample was marked by a pH value >11 as a consequence of serpentinization processes. The water chemistry denotes water/rock interactions with either magmatic or carbonatic rocks in a water reservoir equilibrated at temperatures estimated to be in the range of 58-162 °C. The stable isotope composition of …

Density Functional Theory Calculations Of Equilibrium Oxygen Isotope Fractionation Between Borate Minerals And Aqueous Fluids, Hai-Zhen Wei, Martin Palmer, Jun-Lin Wang, Shao-Yong Jiang, Simon V. Hohl, Yuan-Feng Zhu, Chun Huan, Miao-Miao Zhang, Yeşi̇m Yücel Öztürk

Turkish Journal of Earth Sciences

Borax, ulexite, and colemanite minerals are by far the most important economic source of boron and occur almost exclusively in nonmarine evaporite deposits. While much is known about the geological setting in which they are found, surprisingly little is known about the chemical and physical properties of the brines from which they are formed. Oxygen isotope studies have the potential to reveal important new information regarding borate formation, but unlike most other common oxygen-bearing salts precipitated from brines, there are no experimental data regarding the oxygen isotope fractionation factors between borates and brines. As a first attempt to address this …

A Review Of The Geothermal System Evolution And Distribution In The Central Anatolian Crystalline Complex (Türkiye), Mehmet Furkan Şener, Muhammed Zeynel Öztürk, Alper Baba

Turkish Journal of Earth Sciences

Türkiye is located in the Mediterranean sector of the Alpine-Himalayan tectonic belt and is among the foremost seven countries in the world having an abundance of geothermal resources. The Central Anatolian Crystalline Complex (CACC) is one of the most important geothermal regions in Türkiye. This study aims to evaluate the geothermal system of CACC using the geological, structural, and hydrogeochemical properties that were obtained from previous studies. The present study investigated and evaluated the hydrogeochemical and isotopic properties of 762 water samples belonging to 45 different localities from 41 scientific studies. The result shows that CACC has different heat sources …

Dynamics Of A Giant Slow Landslide Complex Along The Coast Of The Aral Sea, Central Asia, Gökhan Aslan, Marcello De Michele, Daniel Raucoules, François Renard, John Dehls, Ivanna Penna, Reginald Hermanns, Zi̇yadi̇n Çakir

Turkish Journal of Earth Sciences

We report here a slow-moving landslide complex of the lateral spreading type revealed by Sentinel-1 interferometric timeseries analysis. Located along the western coast of the Aral Sea, with a >150-km length and 3-km width, a giant active landslide complex, slides with a constant velocity of up to 60 mm/year. Systematic subsidence up to 5 mm/year is also observed along narrow strips of terraces that appear to result from rotations of fault-bounded blocks. The landslide deformation velocity does not correlate with the annual variations of the water level in the southwestern lake of the Aral Sea during the observation period of …

Mineralogical-Petrographical Features, Geochemical Characteristics, And S Isotope Variability Of Pb-Zn Deposits In The Sakarya Fragment Of The Biga Peninsula (Nw Türkiye), Gökhan Demi̇rela, Si̇nan Akiska, Eli̇f Akiska

Turkish Journal of Earth Sciences

The Biga Peninsula in northwestern Anatolia, a part of the Alpine-Himalayan orogenic belt, has a complex geology that was formed following the closure of the northern branch of the Neotethys. Intense volcanism and plutonism in the area from the Eocene to the Middle Miocene period caused several Pb-Zn-Cu±Ag±Au deposits to form. The geometry of the mineralizations is largely made up of polymetallic veins, manto-chimneys, and irregular replacement bodies. Ore-bearing and host rocks in the mineralization zones and the wall rocks outside the mineralization zones were compiled in this study. The most common minerals in the skarn zones are garnet, pyroxene, …

Forest Fire Effects On Snow Storage And Melt Across Scales Of Forest Recovery In The Western Oregon Cascades, Megan Nicole Guinn

Dissertations and Theses

Snow is the largest component of water storage in the western United States, it serves as a key moisture source for forested ecosystems and is fundamentally linked to streamflow and nutrient cycling. Snow is vulnerable to climatic warming, and a key consequence of declining mountain snowpack is the escalation in wildfire frequency, extent, intensity, and duration across the seasonal snow zone. Fire modifies the spatial extent of snow in watersheds, reducing snow water storage and timing of melt across burned forests. Forested mountain ecosystems and water supplies are facing shifts in their structure, function, and succession. Previous research has focused …

Rank Of Kozlu Formation Coals In The Zonguldak Basin: Implications For Coalbed Gas, Mehmet Namik Yalçin, Cemi̇l Seyi̇s, Sedat İnan

Turkish Journal of Earth Sciences

Carboniferous bituminous coals of the Zonguldak Basin have been mined for over a century. Due to underground mining activity, there have been several fatal incidents related to gas explosions. The gas content of the coals varies greatly in the basin mainly based on coal maturity (rank), increasing with increasing coal depth. In this study, we report a map for coal depth and coal rank in the Kozlu-Üzülmez-Karadon districts of Zonguldak Basin with hope the that it would aid coal gas exploration/exploitation and also coal gas degassing efforts for safer underground mining production in the Zonguldak Basin.

Zircon Grain Shape Parameters From Ignimbrites Of The Central Anatolian Volcanic Province (Cavp) With Implications For Petrogenetic Processes, Lütfi̇ye Akin

Turkish Journal of Earth Sciences

Zircon morphology parameters reflect the physicochemical conditions during crystallization and can be modified by different processes. Zircon populations from Miocene-Pliocene ignimbrites of the Central Anatolian Volcanic Province (CAVP) were studied to reveal relations between the external morphology of zircons and petrogenetic processes. Descriptive grain shape parameters (e.g., minor and major axes, area, perimeter, aspect ratio, roundness, and circularity) were automatically measured from transmitted light images of zircons by a graphical application called AnalyZr. Principal component and cluster analysis were used to determine potential shape descriptors (perimeter, major and minor axis length, and maximum and minimum Feret) for characterizing grains from …

Application Of Model-Based Time Series Prediction Of Infrared Long-Wave Radiation Data For Exploring The Precursory Patterns Associated With The 2021 Madoi Earthquake, Jingye Zhang, Ke Sun, Junqing Zhu, Ning Mao, Dimitar Ouzounov

Mathematics, Physics, and Computer Science Faculty Articles and Research

Taking the Madoi M_S 7.4 earthquake of 21 May 2021 as an example, this paper proposes using time series prediction models to predict the outgoing long-wave radiation (OLR) anomalies and study short-term pre-earthquake signals. Five time series prediction models, including autoregressive integrated moving average (ARIMA) and long short-term memory (LSTM), were trained with the OLR time series data of the aseismic moments in the 5° × 5° spatial range around the epicenter. The model with the highest prediction accuracy was selected to retrospectively predict the OLR values during the aseismic period and before the earthquake in the area. It …

Seasonal Dynamics Of Karst Surface Dissolution Based On A Limestone Tables Experiment (Slovak Karst), Alena Gessert, Zdenko Hochmuth

International Journal of Speleology

Chemical denudation in karst is the basic process of karst relief formation. However, it is influenced by many factors of varying intensity that depend on the climatic conditions and characteristics of each given location. Based on measurable results of weight loss of limestone tablets, we monitored the intensity of chemical denudation in two areas of the Slovak Karst, Silica Plateau and Jasov Plateau that are situated in the most developed karst plateau region of Slovakia. Both experimental sites are similar in terms of geographical conditions, thus comparable between them. In each locality, we placed three sets of standardized tablets at …

Archean (3.3 Ga) Paleosols And Paleoenvironments Of Western Australia, Gregory J. Retallack, Mark D. Schmitz

Geosciences Faculty Publications and Presentations

The Pilbara craton of northwestern Australia is known for what were, when reported, the oldest known microfossils and paleosols on Earth. Both interpretations are mired in controversy, and neither remain the oldest known. Both the microfossils and the paleosols have been considered hydrothermal artefacts: carbon films of vents and a large hydrothermal cupola, respectively. This study resampled and analyzed putative paleosols within and below the Strelley Pool Formation (3.3 Ga), at four classic locations: Strelley Pool, Steer Ridge, Trendall Ridge, and Streckfuss, and also at newly discovered outcrops near Marble Bar. The same sequence of sedimentary facies and paleosols was …

Self-Organization For Community Resilience In An Invisible Agricultural Community, Anna Erwin, Chelsea A. Silva, Zhao Ma

School of Earth, Environmental, & Marine Sciences Faculty Publications

This study investigates how self-organizing efforts by residents of informal settlements, primarily migrant and informal farmworkers, shape community resilience in Majes, a water-scarce irrigation district in the Atacama Desert of Peru. We collected 45 semi-structured interviews with residents and authorities in Majes and analyzed findings through a framework of self-organizing. Analyses revealed that self-organizing by residents of informal settlements incorporated the three components of White’s theory of Community Agency and Community Resilience, which contends that marginalized communities increase resilience by fostering a commons praxis, practicing a prefigurative politics, and developing opportunities for economic autonomy. We also found …

A Field, Petrological, And Geochronological Investigation Of The Chief Joseph Dike Swarm, Mary Joyce Mass

Dissertations and Theses

The Columbia River Basalt Group is the youngest continental flood basalt province in the world and covers an aerial extent of 210,000 km² covering Oregon, southern Washington, and eastern Idaho. Eruptions occurred between approximately 17 million and 6 million years ago, with 92% of eruptions occurring within the first million-year interval. Aside from mapping and some bulk compositional data, few studies have focused on the Chief Joseph dike swarm in NE Oregon, the main eruptive center of the Columbia River Basalt Group. Prior to this study there were no published age dates for the Chief Joseph dike swarm.

This …

Research On Three-Stage Automatic Hole Packer For Gas Extraction Drilling In Underground Coal Mine, Wang Qingfeng, Shi Shuhan, Xin Dezhong, Chen Hang, Zhang Shitao

Coal Geology & Exploration

In view of the requirements of hole sealing during gas extraction drilling in underground coal mine for manual packer installation and sealing material injection, as well as the low automation level of hole sealing technology, a three-stage automatic hole packer for gas extraction drilling in underground coal mine was developed, with the appearance similar to the drill pipe. The hole packer could be mechanized into the drilling hole by an automatic drilling machine, and realize the automatic injection of sealing material. Herein, the Mooney-Rivlin hyperelastic constitutive model was used to represent the strain energy function by the finite element analysis …

Intelligent Optimization And Control Technology For Drilling Process Of Coal Mine Tunnels, Yao Ningping, Wu Min, Chen Luefeng, Lu Chengda, Fan Haipeng, Zhang Youzhen, Li Wangnian, Yao Ke

Coal Geology & Exploration

The harsh environment for drilling construction of coal mine tunnel, complex coal seam structure and complicated operation procedures can cause low drilling efficiency and high drilling cost. For this reason, it is imperative to carry out studies on the optimization and control technology for the drilling process of coal mine tunnel. Herein, study was conducted from intelligent identification of lithology of coal-bearing formation, intelligent optimization of drilling parameters and their intelligent control, focusing on the key technology for control of drilling process of coal mine tunnel. First, in order to accurately determine the type of coal-bearing formation, an intelligent identification …

Research Status And Development Trend Of Near-Bit Mwd In Underground Coal Mine, Hao Shijun, Chu Zhiwei, Li Quanxin, Fang Jun, Chen Long, Liu Jianlin

Coal Geology & Exploration

Near-bit meusurement while drilling (MWD) integrates several key technologies such as near-bit multi-parameter measurement, power supply and communication across positive displacement motor drills, turbine continuous power generation and high-speed mud pulse wireless transmission, capable of obtaining various types of parameters near the bit. It is one of the key components of intelligent drilling technology in underground coal mine. Herein, the limitation of the existing technology applied in coal mine was analyzed with full reference to the development experience and development path of near-bit MWD in the field of surface oil and gas drilling. Meanwhile, the research idea of near-bit MWD …

Continuous And Discontinuous Numerical Simulation Of The Rock Breaking Process Of Pdc Drill Bit Under Composite Impact, Qin Chengshuai, Sun Hongbin, Li Liping, Liu Xuegang, Liu Zhihui, Feng Chun, Sun Zizheng

Coal Geology & Exploration

Composite impact drilling is a novel rock-breaking technique that combines both axial and torsional impacts. To address the issues of complex failure mechanisms and unclear rock-breaking mechanisms under the axial-torsional impacts on rock by Polycrystalline Diamond Compact (PDC) drill bits, a FEM-DEM rock model based on shared nodes was established using the Continuous Discontinuous Element Method (CDEM), and the rationality of this computational model was verified through laboratory uniaxial compression experiments. Besides, a composite impact motion model for single drill bit was built through the secondary development of JavaScript, and the composite impact rock-breaking process of single PDC drill bit …

Application Of Intelligent Direct Push Measurement While Drilling Device For Environmental Geological Surveys, Sun Pinghe, Zhou Shengwei, Cao Han, Gao Qiang, Cheng Gongbi, Zhang Hui

Coal Geology & Exploration

In order to solve the technical challenges of inaccuracy and poor credibility of contaminant survey results due to the low accuracy of drilling trajectories in environmental geological surveys, the structural and functional characteristics of the existing direct-push drilling tools were analyzed. On this basis, the method of near-bit measurement while drilling using single-action combination was proposed. An intelligent measurement-while-drilling (MWD) device was developed, a laboratory platform monitoring module was established, a set of monitoring software was developed, and the stability and reliability of the intelligent MWD device was analysed. Then, verification tests have been carried out on the laboratory platforms …

Wear Law And Design Of Assembling Diamond Bit Based On Finite Element Analysis, Yang Zhan, Tan Songcheng, Yang Kaihua, Fang Xiaohong

Coal Geology & Exploration

In addition to coring drilling, full (non-coring) drilling also occupies a large proportion in the energy exploration and development. Non-coring drilling can reduce the high time cost of lifting and lowering work required for coring, thereby increasing the net drilling time, improving the drilling efficiency and reducing the drilling costs. The traditional non-coring drill bits are prone to uneven wear on the bit surface during the drilling process. To identify and improve this law of uneven wear, it was herein proposed to use the assembling non-coring bit to improve the eccentric wear of bit. For this reason, numerical simulation analysis …

Table Of Contents, The Editors

Coal Geology & Exploration

No abstract provided.

Attenuation Model And Law Of High-Frequency Drilling Fluid Pressure Wave, Zhou Botao, Su Yinao, Wang Jiajin

Coal Geology & Exploration

The technology of transmitting high-frequency drilling fluid pressure wave information with high transmission rate. It is also one of the key technologies to achieve the automated and intelligent drilling. However, the field application of this technology is hindered by the substantial attenuation experienced by high-frequency drilling fluid pressure waves during the transmission process. Thus, exploring the attenuation characteristics of these waves is crucial for the development of high-speed transmission technology. Herein, it is assumed that the drilling fluid pressure is equivalent on the same section of drill string, and the flow rate of drilling fluid is radially distributed. On this …