Earth Sciences Commons^™

Assessing The Impact Of Hurricane Fiona On The Coast Of Pei National Park And Implications For The Effectiveness Of Beach-Dune Management Policies, Robin Davidson-Arnott, Jeff Ollerhead, Elizabeth George, Chris Houser, Bernard Bauer, Patrick Hesp, Ian Walker, Irene Delagado-Fernandez, Danika Van Proosdij

Earth & Environmental Sciences Publications

The impact of waves, storm surge, and aeolian transport associated with Post-tropical Storm Fiona (offshore significant wave height ∽ 8 m, storm surge up to 2 m) on the sandy beaches and foredunes of the north shore of Prince Edward Island National Park (PEINP), Canada, are assessed. Management policies and practices, as they apply to sandy beach systems within PEINP, are reviewed in the context of the shoreline changes attributed to Fiona. The effectiveness of these policies and practices are evaluated to inform the potential performance of beach-foredune systems as natural protection measures that mitigate the impacts of large-magnitude storms …

Using Bayesian Multispecies Models To Evaluate Fish And Invertebrate Detection Probability And Distribution In The Hypersaline Bahia Grande Tidal Basin, Roy M. Ulibarri, Catherine M. Eckert, David Hicks, David Montagne, Brandon Jones, David R. Stewart

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

Objective

In 2000, the Laguna Atascosa National Wildlife Refuge acquired the Bahia Grande (Texas) management unit, a space that had lain barren and arid for 70 years. A large cooperative partnership launched a restoration project to replenish the basin and recover its original tidal hydrology. In 2005, the construction of a pilot channel successfully restored water throughout the basin, and plans to eventually widen the channel were developed. Our study aims to evaluate an estuarine habitat restoration by assessing ecological drivers and the impacts on species diversity.

Methods

We evaluated species richness, detection/occupancy rates, and species–habitat relationships, and we estimated …

What Climate Change Means For Nebraska

United States Environmental Protection Agency: Staff Publications

Nebraska’s climate is changing. In the past century, most of the state has warmed by at least one degree (F). The soil is becoming drier, and rainstorms are becoming more intense. In the coming decades, flooding is likely to increase, yet summers are likely to become increasingly hot and dry, which would reduce yields of some crops, require farmers to use more water, and amplify some risks to human health.

Our climate is changing because the earth is warming. People have increased the amount of carbon dioxide in the air by 40 percent since the late 1700s. Other heat-trapping greenhouse …

Urban And Rural Bmi Trajectories In Southeastern Ghana: A Space-Time Modeling Perspective On Spatial Autocorrelation, Hsiao-Chien Shih, Xiaoxiao Wei, Li An, John Weeks, Douglas Stow

International Journal of Geospatial and Environmental Research

Spatial autocorrelation in model residuals can have a significant impact on the results of spatial or space-time models. This can result in misleading estimates of the influence of different factors, potentially exaggerating or even reversing the perceived effects of these factors. This study also considers the potential implications of the Modifiable Areal Unit Problem (MAUP) in the context of spatial-temporal models. In this case study for southeastern Ghana, we examined whether and how spatial autocorrelation in model residuals might generate bias in regression coefficients when explaining women’s body mass index (BMI) across urban and rural areas. Eigenvector spatial filtering, with …

Biotechnology For Sustainable Materials: Innovating Today For A Greener Tomorrow, Shashi Kant Bhatia, Saurabh Bhatia, Maria Eugenia Inda-Webb, Konstantina Kourmentza, Tae Seok Moon, Vijai Singh, Vishal Ahuja, Jingbo Li, Sanjeet Mehariya, Jikai Zhao

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

No abstract provided.

A Simulation Study Of Mechanisms Behind Water Inrush From Fault-Bearing Floors Of Ultra-Thick Coal Seams Under Loading And Unloading At Significantly Variable Amplitude, Li Hao, Zhu Kaipeng, Guo Guoqiang, Zhou Yang, Kang Zhiqin

Coal Geology & Exploration

Ultra-thick coal seams feature large stope spaces and extensive disturbance ranges. Significantly variable amplitude loading and unloading are prone to cause the fault rupture of floors of ultra-thick coal seams, inducing water disasters. Numerical simulation serves as a critical method for revealing the fault reactivation and water inrush mechanisms at the floors of ultra-thick coal seams. The key of this method is to accurately inflect the coupling characteristics of rock mass rupture and fissure water under significantly variable amplitude loading and unloading. This study determined the correlations of the damage variable with plastic strain and stress, deriving the equations for …

Construction And Analysis Of A Method For Grading Long-Term Vegetation Carbon Sink In Waste Dumps Of An Open-Pit Coal Mine, Yang Fei, Cui Kuankuan, Zhang Chengye, Li Jun, Wang Jinyang, Du Tianmeng, Zhang Haoran

Coal Geology & Exploration

Vegetation carbon sink serves as a crucial indicator for the ecological assessment of an open-pit coal mine. The accurate inversion and grading of vegetation carbon sink play a significant role in exploring the ecological restoration of coal mines. This study proposed a method for grading vegetation carbon sink of an open-pit coal mine based on the particle swarm optimization (PSO) algorithm. Specifically, using a light use efficiency (LUE) model, this study first determined the spatio-temporal distributions of the 2005‒2020 vegetation carbon sink in the waste dumps of the Shengli No.1 open-pit coal mine through inversion based on Landsat images and …

Development Of Remote Control System For Automatic Drilling Rig Used In Coal Mine, Dong Hongbo, Yao Ningping, Wang Tianlong, Ma Bin, Peng Guangyu

Coal Geology & Exploration

In response to the problems of high labor intensity and great safety risk of drilling rig under the complex construction environment, a set of remote monitoring system for automatic drilling rig of coal mine was developed using the electronic circuit, measurement sensing, remote control, video monitoring and big data technologies. The system, based on ZDY4500LFK coal mine drilling rig, has implemented the three control modes: in-line-of-sight control, underground centralized control and ground remote monitoring. Besides, a cloud automatic drilling rig management and control platform was established. Specifically, the in-line-of-sight monitoring is used to realize the accurate operation of drilling rig …

Water Inrush Mechanism And Water-Conducting Fractured Zone’ Developmental Patterns Of A Typical Ultra-Thick Coal Seam In The Huanglong Coalfield During Fully Mechanized Mining, Yan Heping, Li Wenping, Duan Zhonghui, Yang Yugui

Coal Geology & Exploration

The mining of thick coal seams in the Huanglong Jurassic coalfield has led to the formation of high water-conducting fractured zones, which are prone to connect the extremely thick sandstone aquifers of the overlying Cretaceous Luohe Formation. Qinggangping Coal Mine in the coalfield exhibits the typical characteristics of pulsed water inrushes during coal mining, posing a severe threat to safe mining. This study investigated the fully mechanized mining face 42105 in Qinggangping Coal Mine. Using 3DEC discrete element simulation, flushing fluid leakage in boreholes, integrated geophysical exploration, and borehole TV, this study examined the developmental patterns of the water-conducting fractured …

Research On Digital Twin-Driven Tracking, Positioning And Collision Detection Method Of Excavating And Anchoring Equipment, Yang Wenjuan, Zhao Dian, Zhang Xuhui, Chen Xin, Zheng Xili, Liu Yanhui, Zhang Ran, Wan Jicheng

Coal Geology & Exploration

The automation of excavating and anchoring operation is critical for intelligent excavation of coal mine roadway. Aiming at the challenges of relative pose measurement and collision detection during the alternating operation of the current excavating and anchoring equipment, a digital twin-driven tracking, positioning and collision detection method was proposed. Firstly, in order to overcome the influence of low illumination, high dust and complex background interference in the underground excavating face, the multi-point infrared LED target is taken as the information source, the infrared LED feature point image is collected by industrial camera, the center of the spot is extracted using …

Intelligent Identification Method Of Drilling Fluid Rheological Parameters Based On Machine Learning, Liu Changye, Yang Xianyu, Cai Jihua, Wang Ren, Wang Jianlong, Dai Fanfei, Guo Wanyang, Jiang Guoshe, Feng Yang

Coal Geology & Exploration

The rheology of drilling fluid, which characterizes its flow and deformation, is vital for transporting and suspending rock cuttings as well as for enhancing the drilling rate. Precise control of drilling fluid rheological parameters is essential to ensure borehole cleanliness and efficient drilling. This paper proposes an intelligent identification method for drilling fluid rheological parameters based on Convolutional Neural Networks (CNNs). The method employs magnetic stirring to generate stable images of drilling fluid flow, uses various data augmentation methods to increase the number of images and create a database, thereby enhancing the model’s robustness and generalization capabilities. The AlexNet CNN …

Weight And Resistance Reduction Mechanism Of Drilling Rods For Drilling In Soft Coal Seam And Its Application, Wang Yonglong, Guo Jiakuan, Yu Zaijiang, Du Kang, Sun Yuning

Coal Geology & Exploration

Gas drainage boreholes during construction is a necessary means to control gas hazards. In response to the issues such as high drilling resistance, low drilling efficiency, and high labor intensity caused by the significant self-weight of the drilling rod in drilling into the soft coal seams, a research approach of reducing the self-weight and lowering the drilling resistance by optimizing the drilling rod structure was proposed. Thus, a four-winged concave grooved drilling rod was designed to address both of its advancing resistance and rotating torque losses. Meanwhile, a drilling resistance model for the drilling rod was established. On this basis, …

Table Of Contents, The Editors

Coal Geology & Exploration

No abstract provided.

A Preliminary Study Of Coalbed Methane Adsorption At Fractal Interfaces, Jin Yi, Li Yani, Song Huibo, Zhao Mengyu, Yang Yunhang, Chen Zenan

Coal Geology & Exploration

The adsorption and desorption mechanisms of coalbed methane (CBM) are foundational for revealing CBM accumulation mechanisms and achieving efficient CBM exploitation. Studies have indicated that coal reservoirs exhibit complex pore structures with fractal features, significantly influencing CBM adsorption at pore-solid interfaces. Based on a comparative analysis of several common adsorption models for gas-solid interfaces and a summary of their characteristics and applicable conditions, this study suggests that all these adsorption models still rely on the stationary assumption of adsorption selectivity for the description and application of CBM adsorption behavior at fractal interfaces while overlooking the scale invariance of the adsorption …

Dynamic Mechanisms Of Coal And Gas Outbursts Based On A Multi-Zone Combined Coal Model, Li Feng, Wang Chenchen, Wang Bo, Jing Yadong, Yan Zhengxu, Zhang Minbo

Coal Geology & Exploration

Coal and gas outbursts (hereafter referred to as outbursts) severely affect coal mining safety. However, many scientific problems underlying the outbursts remain unsolved. To minimize the influence of anisotropy in the mechanical properties of coals on research into outbursts, this study constructed a multi-zone combined coal model. Based on the stress distribution of overlying strata and the stress wave propagation mechanisms, this study located the weak zone of coals, shrinking the research object from the outburst center to the weak zone. Given that outbursts are triggered by the disturbance of external dynamic load, this study examined the propagation patterns of …

Carbon Microspheres In Natural Coke: Optical Microscopic Characteristics And Their Origin And Implications, An Yanfei, Chen Kaixin, Wang Yaqiao, Cheng Shuo, Huang Jian, He Shuyang, Wang Shengjian

Coal Geology & Exploration

Carbon microspheres (CMs) in natural coke are formed when coal seams undergo magma-induced rapid thermal metamorphism. Analyzing the origin of the optical microscopic characteristics of CMs assists in gaining deep insights into the rapid thermal carbonization and metamorphism of coals. This study examined the natural coke samples rich in CMs from Shitai Coal Mine in Huaibei, Anhui Province. Using experiments like high-resolution reflected polarized light microscopy and scanning electron microscopy (SEM), this study characterized the particle sizes, distribution, optical microscopic characteristics, and ultramicrofabrics of CMs in natural coke, revealing the origin and thermal evolution implications of their optical anisotropy. The …

Evolutionary Mechanisms And Models Of Strain, Porosity, And Permeability Of Compacted Broken Coals, Li Lei, Lu Shouqing, Chu Tingxiang, Zhong Xiaoxing, Liu Chongyang, Ren Ting

Coal Geology & Exploration

Residual coal areas in caving zones of goaves in coal mines serve as primary sites for low-temperature reactions between coal and oxygen. Hence, exploring the evolutionary models of the strain, porosity, and permeability of coals in these areas holds great significance for gaining a deep understanding of the spontaneous combustion process and regularity of coals. Based on the self-developed experimental device for gas seepage in compacted broken coals, this study explored the evolutionary patterns of the strain, porosity, and permeability of compacted coals with single/mixed particle sizes during gas seepage. Furthermore, this study analyzed the variations in the strain, porosity, …

Botdr-Based Horizontal Deformation Monitoring Of Section Coal Pillars, Chai Jing, Hao Hongru, Yang Jianfeng, Gao Dengyan, Gao Kuiying, Chen Jianhua, Yang Lei, Liu Zeyu

Coal Geology & Exploration

To address potential safety hazards like microcrack initiation, deformation, and failure inside coal pillars, this study monitored the horizontal deformations of coal pillars using the Brillouin optical time-domain reflectometry (BOTDR)—a distributed optical fiber sensing technology. Firstly, this study established a method for converting the axial strain of optical fibers into horizontal deformations based on a theoretical analysis of the failure and bulking characteristics of coal pillars. Secondly, it determined the axial tensile response of metal-based cord-shaped sensing optical fibers by conducting laboratory tests. Then, it corrected the strain coefficient based on the deformation and failure patterns of coal pillars. Finally, …

Geochemical Characteristics And Influencing Factors Of Deep Coalbed Methane In The Linxing-Shenfu Block, Wu Peng, Hu Weiqiang, Li Yangbing, Ma Litao, Li Yong, Zhao Fei, Niu Yanwei, Chen Jianqi, Li Panpan, Liu Zaizhen, Li Chenchen, Cao Di, Liu Cheng

Coal Geology & Exploration

Identifying the origin and geochemical characteristics of deep coalbed methane (CBM) is critical for its exploration and production. This study examined the desorbed gas from deep-CBM parameter wells in the Linxing-Shenfu block on the eastern margin of the Ordos Basin. It systematically tested the composition, content, and carbon isotopes of CBM in coal seams Nos. 8 and 9. In combination with the degree of thermal evolution, gas-bearing properties, coal seam burial depths, geological structures, and hydrogeologic conditions, it delved into the geochemical characteristics and influencing factors of deep CBM. The results show that the deep CBM in the study area …

Dynamic Simulations And Applicability Evaluation Of Novel Perforation Techniques, Bi Gang, Yuan Peijie, Han Fei, Fu Shuaishuai, Wu Jiemin, Ma Ying

Coal Geology & Exploration

The development and improvement of perforated completion techniques hold great practical significance and value for efficient testing and exploitation of oil and gas fields. However, conventional shaped-charge perforation for well completion of low-permeability reservoirs (e.g., low-permeability coal seams) suffered high seepage resistance and reduced productivity due to the presence of compaction damage zones. To achieve enhanced exploitation efficiency of low-permeability reservoirs, novel perforation techniques, including self-cleaning and after-effect perforation, have been proposed. However, their perforation performance and applicability remain ambiguous. Based on the explicit time integration algorithm and fluid-structure interaction mechanism of LS-DYNA, this study proposed a method for finite …

Anti-Channeling Methods For Coalbed Methane Production Using L-Type Horizontal Wells, Liu Zhan, Zhang Qunxia, Geng Yuxin, Luo Dan, Wang Minggang

Coal Geology & Exploration

Coalbed methane (CBM) production using L-type horizontal wells can yield stable single-well production of up to above 8 000 m³/d. However, due to the lack of sand settling pockets, L-type horizontal wells fail to achieve gas-water separation under the action of gravity. Consequently, gas channeling from tubing is prone to occur, significantly decreasing pumping efficiency and restricting further drainage and pressure reduction. By optimizing the lifting process for production in the early stage, the gas channeling from tubing has been somewhat alleviated. However, the anti-channeling effects remain unsatisfactory in low-fluid-pressure and high-yield gas wells. This study examined L-type …

Technologies For Water Hazard Prevention And Control In Burnt Rock Aquifers Within Concealed Burnt Areas, Wang Hai

Coal Geology & Exploration

Burnt rocks are extensively distributed in northwestern China, featuring well-developed pores and fractures and abundant water, emerging as primary aquifers in this region. The burnt rocks in concealed burnt areas in this region show inconspicuous surface remains, complicating their identification. Penetrating burnt rock aquifers in coal mining will lead to water hazard and destroy water resources in these aquifers. To prevent and control water hazard in burnt rocks within concealed burnt areas and preserve water resources in burnt rock aquifers, this study analyzed the distributions of burnt rocks in China and the effects of water in them on coal mining. …

Exploring A Fly Ash-Based Grouting Material For Toughening Through In Situ Polymerization Of Acrylamide, Zhang Yuehong, Wang Xiaodong, Wang Hai, Wu Boqiang, Ji Zhongkui, Zhu Shibin, Han Le, Feng Longfei

Coal Geology & Exploration

Efficiently controlling the water inflow (loss) of burnt rocks in the roof of coal mining faces requires grouting reinforcement materials with excellent compressive toughness. Silicate cement-based grouting materials, characterized by low costs, have been extensively applied to grouting reinforcement in coal mines. However, their hardened grout is susceptible to deformation, exhibiting poor toughness. By employing the in-situ polymerization of acrylamide (AM) for toughening, this study investigated the effects of AM, cross-linking agent, initiator, and water-cement ratio on the setting time, swelling capacity, compressive strength, and toughness index of the fly ash-based grouting materials. Furthermore, the microstructures of the hardened grout …

Some Reflections On The Application Of Machine Learning To Research Into The Theoretical System Of Mine Water Prevention And Control, Yao Hui, Yin Huichao, Liang Manyu, Yin Shangxian, Hou Enke, Lian Huiqing, Xia Xiangxue, Zhang Jinfu, Wu Chuanshi

Coal Geology & Exploration

The theoretical system of mine water prevention and control encompasses three fundamental aspects: disaster-causing mechanisms, risk evaluation, and disaster prediction. This theoretical system, having undergone rapid development over the past 20 years, aims to gain insights into the behavior characteristics of mine water and predict its evolutionary trend, thus serving the prevention and control of water disasters in mining areas. Applying machine learning, a powerful tool for data analysis and mining in the era of big data, to research into the theoretical system has garnered considerable attention. This study focuses on the specific applications of machine learning to the three …

The Influence Of Soil Composition On Stormwater Retention And Runoff In Green Roofs At Portland State, Manuel Edrozo, Lily Green, Mitchell Mcdonald, Nicholas Olmos

Student Research Symposium

The purpose of this study is to determine what soil composition is best for green roofs at Portland State; we aim to compare the current soil to the original substrate, to measure which composition retains the most water, and which filters out the most pollutants in stormwater runoff. Five different soil compositions were tested — original, current, layered mixed, solid mixed, and potting soils — and 1,000mL of high and low intensity rainfall (in/hr) was simulated for each of the mixtures. Water was allowed to filter through the soils for a predetermined time (10min for a high application rate and …

Effects Of Urbanization On Eutrophication Parameters In Three Tidal Creeks, Ella Swantek

Honors Theses

Marshes and swashes are vital environments as a controlling barrier between land affected by various pollutants and the ocean. Eutrophication and the effects of this process can be detrimental for the areas experiencing it. I am interested in ways areas that have little contact with human interactions compare to areas that are heavily urbanized, and whether either of these locations is at a higher risk for eutrophication. Using spectrophotometry and fluorometry, I analyzed samples collected from the relatively undeveloped and restricted-access locations of Waities Island Beach and Dunn Sound monthly for dissolved nutrients, and chlorophyll. At the time of sampling, …

Sedimentary Conditions At A Tidal Creek That Exhibits Seasonal Pelagic-Benthic Variations, Jack B. Corbin

Honors Theses

Tidal creeks in the Grand Strand of South Carolina are small but numerous connectors between land and ocean. One of these creeks, White Point Swash, exhibits a seasonal switch between planktonic and benthic photosynthesizers. As plankton become less abundant in fall, benthic macroalgae bloom, aided by lower water levels due to fall-winter dredging of the main channel, until late Spring. This study builds on previous findings and examines sedimentary conditions at this site further. Sedimentary chlorophyll a (in microphytobenthos) and pore water nutrient concentrations are confirmed to be higher than water-column concentrations. Sedimentary nutrient fluxes to the sediment-water interface, calculated …

Impacts Of Hurricane Idalia’S Surge On Coastal Sand Biogeochemistry, Wendy "Cor" Mchone

Honors Theses

Beaches are heavily influenced by extreme events, such as hurricanes. Biological and chemical processes, such as primary production and diagenesis are often interrupted by these events. To examine the effects of hurricanes on coastal biogeochemistry, this study used sand and porewater samples from Waties Island, SC, which were collected before and after Hurricane Idalia. The samples were analyzed for macronutrient concentrations, organic content, and chlorophyll concentrations. Macronutrient pore water concentration changes were not uniform. The inventory of nitrite decreased significantly after the storm, which was reflected in slight increases in the inventories of nitrate and ammonium. Concentrations of nitrate, which …

Rice Biomass Response To Various Phosphorus Fertilizers In A Phosphorus-Deficient Soil Under Simulated Furrow-Irrigation, Jonathan B. Brye

Crop, Soil and Environmental Sciences Undergraduate Honors Theses

Wastewater-recovered phosphorus (P), in the form of the mineral struvite (MgNH4PO4⋅6H2O), may provide a sustainable alternative to rapidly decreasing rock phosphate reserves. Struvite can be generated via chemical and/or electrochemical precipitation methods, potentially reducing the amount of P runoff to aquatic ecosystems. The objective of this greenhouse tub study was to evaluate the effects of chemically- and electrochemically precipitated struvite (CPST and ECST, respectively) on above- and belowground plant response in a hybrid rice cultivar (Gemini 214, RiceTec) grown using furrow-irrigation compared to other common fertilizer-P sources [i.e., triple super phosphate (TSP) and diammonium phosphate (DAP)] in a P-deficient silt …

The Effect Of Agrivoltaics On Irrigation Water Consumption In Central California, London Camba

Undergraduate Theses

An agricultural system where solar energy generation and agricultural systems are used together for mutual benefit, agrivoltaics reduces loss of water due to evaporation, particularly in drylands. Central California has faced extreme droughts, and water has become a scarce resource. However, the wide-scale use of agrivoltaics has been limited due to lack of knowledge about agrivoltaics and also the lack of funding for start-up agrivoltaics projects. Therefore, this research investigated the potential for agrivoltaics in Central California to reduce irrigation water consumption using a review of multiple crop studies using agrivoltaics to determine an optimal crop for agrivoltaics and a …