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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

The determination of joint system characteristics from azimuthal resistivity surveys

Fleming, Anthony H. January 1986 (has links)
Thesis (M.S.)--University of Wisconsin--Madison, 1986. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 189-199).
2

Περιβαλλοντική μελέτη της λεκάνης του Θολοποτάμου ποταμού, δήμου Αιγείρας

Γιαννοπούλου, Χριστίνα 01 August 2014 (has links)
Η παρούσα μεταπτυχιακή διατριβή ειδίκευσης εκπονήθηκε στο Τμήμα Γεωλογίας του Πανεπιστήμιου Πατρών, στα πλαίσια του Προγράμματος Μεταπτυχιακών Σπουδών με γενικό θέμα «Γεωεπιστήμες και περιβάλλον». Σκοπός της εργασίας είναι η περιβαλλοντική και υδρογεωλογική μελέτη της λεκάνης του Θολοποτάμου ποταμού, Δήμου Αιγείρας, ενώ η ευρύτερη περιοχή έρευνας περιλαμβάνει επίσης τις υδρολογικές λεκάνες των ποταμών Κράθι και Κριού. Προκειμένου να εξαχθούν τα κατάλληλα αποτελέσματα, προηγήθηκε επεξεργασία και μελέτη των γεωλογικών, υδρογεωλογικών και μετεωρολογικών συνθηκών που επικρατούν στην περιοχή, ύστερα από την απαραίτητη συλλογή δεδομένων. Η ευρύτερη περιοχή χαρακτηρίζεται ως επί το πλείστον από πρόσφατους Πλειο-Πλειστοκαινικούς και Τεταρτογενείς σχηματισμούς στο πεδινό και ημιορεινό της τμήμα, ενώ στις πιο ορεινές τοποθεσίες οι σχηματισμοί είναι αλπικοί και συγκαταλέγονται κυρίως στη γεωτεκτονική ζώνη Ωλονού – Πίνδου. Πιο συγκεκριμένα, στην πεδινή περιοχή, εμφανίζονται σε μεγάλη έκσταση μάργες, ψαμμίτες και κροκαλοπαγή, συνιστώντας έτσι το κύριο υδροφόρο στρώμα της περιοχής, ενώ στα μεγαλύτερα υψόμετρα διακρίνουμε ασβεστόλιθους της ζώνης Πίνδου αλλά και της ζώνης Τριπόλεως. Από τεκτονικής άποψης, η περιοχή είναι ιδιαίτερα ενεργή, γεγονός που έχει παίξει καθοριστικό ρόλο στην μεταλπική ιζηματογένεση, στη διαμόρφωση της γεωμορφολογίας αλλά και στην ανάπτυξη του υδρογραφικού δικτύου. Η εκφόρτιση του συστήματος της περιοχής πραγματοποιείται μέσω ενός πλήθους πηγών, σχηματίζοντας έτσι τις υπό μελέτη υδρολογικές λεκάνες. Όσον αφορά τον Θολοπόταμο, οι πηγές του βρίσκονται σε Πλειο-Πλειστοκαινικό γεωλογικό υπόβαθρο μαργαϊκής σύστασης, σε αντίθεση με τους ποταμούς Κράθι και Κριό, των οποίων οι πηγές εμφανίζονται στην επώθηση της ζώνης Πίνδου με την Τριπόλεως. Σύμφωνα με τις χημικές αναλύσεις που πραγματοποιήθηκαν, τα νερά της υπό έρευνα περιοχής ομαδοποιούνται σε τέσσερις κύριους υδροχημικούς τύπους: Τα νερά με χημικό τύπο Ca-Mg-HCO3 τα οποία αποτελούν το επικρατέστερο τύπο υδάτων της περιοχής, τα νερά με χημικό τύπο Ca-Mg-HCO3-SO4 που έχουν σχετικά μεγάλη εμφάνιση, τα νερά με τύπο Ca-HCO3 που εμφανίζονται ελάχιστα και τέλος αυτά με χημικό τύπο Ca-Na-HCO3-Cl-S που αποτελούν τμήμα της περιοχής και συναντήθηκαν μόνο σε μια τοποθεσία. Επιπλέον, οι τιμές των ιοντικών λόγων Na+/K+ και (Ca2++Mg2+)/(Na++K+) δείχνουν τη διαφοροποίηση μεταξύ των σημείων εμπλουτισμού του υδροφόρου και των σημείων στα κατάντη τμήματα του υδροφόρου, δηλαδή στις περιοχές εκφόρτισης του υδροφόρου. / The purpose of this Master Thesis is to deal with the environmental and hydrochemical conditions of the basin of the river Tholopotamos, in Aigeira, Achaia. The study area also includes the neighboring basins of the rivers Krios and Krathis. In order to export the final results, firstly the necessary data were gathered and then they were appropriately elaborated. The lower and plain regions of the study area consist of recent Pleio-Pleistocene and Quaternary formations, whereas the higher and mountainous regions are comprised of the alpine formations of the Olonos – Pindos geotectonic Zone. Specifically, the plain areas are covered by marls, conglomerates and sandstones which appear in a great scale, comprising the main aquifer bed of the basin of Tholopotamos. On the other hand, the alpine bedrock of the mountainous areas consists of limestone of the Olonos – Pindos or the Tripoli’s Zone. The aquifer discharges through numerous springs that are located on the marls formations, in contrast to the springs of Krathis and Krios basins, which occur on the overthrust of the Olonos zone over the Tripoli’s one. Αccording to the chemical analysis, the study areas’ waters can be classified in three categories: waters with hydrochemical type Ca-Mg-HCO3, which are the most common for the study area, waters with hydrochemical type Ca-Mg-HCO3-SO4 which appear in a rather great scale, waters with type Ca-HCO3 that appear in one area and lastly, those with chemical type Ca-Na-HCO3-Cl-S which were found only in one place.
3

Spatial organisation of groundwater-surface water interactions in an upland catchment : integrating hydrometric, tracer and modelling approaches

Blumstock, Maria Elisabeth January 2017 (has links)
This thesis presents studies of the heterogeneous nature of groundwater-surface water (GW-SW) interactions at the hillslope and catchment scale in the 3.2km2 Bruntland Burn, UK. GW fluctuations were measured within three contrasting hydropedological units. Synoptic hydrogeochemical surveys were carried out (major ions, stable isotopes) to capture the increased influence of GW to the stream during a 10year return period drought. The catchment was shown to have highly dynamic GW stores, with each landscape unit translating into different rainfall-runoff processes. Soil characteristics were shown to be the strongest predictors for variability in GW dynamics. Each soil type was characterised by a unique storage-discharge relationship and threshold response with a certain GW level above which lateral flow dominated. On the lower hillslope, predominating lateral flow and little recharge to depth is supported by hydrologically responsive soils. Connectivity between the steeper slopes and the valley bottom, however, needed persistent wet periods to overcome storage thresholds. Here, vertical flow paths recharging deeper GW dominated, with GW levels falling below the soil layer into the underlying drift. It was found that relatively well mixed, near-surface sources of stream flow predominated in wetter conditions, whilst baseflows are variable and reflect a diverse range of GW stores. Geophysics (ERT) and GW level measurements were integrated into MODFLOW-NWT to simulate GW-SW interactions along a representative 2D-hillslope transect. Although only a preliminary model, it was shown that shallow pathways have much shorter residence times, thus maintaining high water tables in the riparian peatlands, than deeper flow paths discharging through the drift and directly into the stream. Largest sources of GW are located within the drift, resulting in complex spatial patterns of runoff generation. This work illustrated the utility of a basic model to predict GW flow paths, highlighting how water and solutes are stored and released in montane headwater catchments.
4

Υδρογεωλογική μελέτη των καρστικών πηγών της περιοχής της Οκτωνιάς, Κ. Εύβοιας

Λαμπροπούλου, Αικατερίνη 05 March 2012 (has links)
Στα πλαίσια της παρούσας πτυχιακής εργασίας μελετώνται οι υδρογεωλογικές και υδροχημικές συνθήκες που επικρατούν στις καρστικές πηγές της Οκτωνιάς στην Κεντρική Εύβοια. Η περιοχή ανήκει στην Πελαγονική Γεωτεκτονική Ζώνη και αποτελείται από ασβεστόλιθους του Ιουρασικού και Τριαδικού, Αλλουβιακές αποθέσεις και νεογενελις σχηματισμούς. Για ττην υδροχημική έρευνα χρησιμοποιήθηκαν δείγματα από 6 πηγές. Με βάση τα αποτελέσματα των αναλύσεων και με την βοήθεια των διαγραμμάτων Piper τα νερά κατατάσσονται στην ομάδα των γαιοαλκαλικών- οξυανθρακικών νερών. / In the frame of the present undergraduated thesis the hydrogeological and hydrochemical conditions that prevail in the karst springs of Oktonia region in Central Evia are studied. The study area belongs to Pelagonian Geotectonic zone and is constituted of Jurassic and Triassic limestones, Alluvial deposits and Neogene formations. Samples of 6 water springsare collected and analyzed in the laboratory of Hydrogeology in the Department of Geology,University Patras. The waters are classified as geo- alkaline with elevated alkaline percentage. The springs present very low discharge rates.
5

A conceptual model of groundwater flow at the midway, Utah fish hatchery as constrained by geochemical, physical hydrogeological, and geophysical methods /

Durrant, Camille. January 2005 (has links) (PDF)
Thesis (M.S.)--Brigham Young University. Dept. of Geology, 2005. / Includes Bibliographical Information (leaves 22-24).
6

Υδρογεωλογική μελέτη στην περιοχή του Αιγίου

Τριάντου, Γεωργία - Αντιγόνη 07 October 2011 (has links)
Στα πλαίσια της παρούσας διπλωματικής εργασίας συλλέχθηκαν τα μετεωρολογικά δεδομένα της ευρύτερης περιοχής του Αιγίου, διεξήχθησαν μηνιαίες μετρήσεις στάθμης ενώ κατά τον Οκτώβριο του 2008 έγινε δειγματοληψία νερού από πηγάδια της περιοχής, με στόχο να μελετηθούν οι υδρογεωλογικές και υδροχημικές συνθήκες που επικρατούν στην περιοχή και να καθοριστούν οι παράμετροι του υδρολογικού ισοζυγίου. Η περιοχή μελέτης ανήκει στον νομό Αχαΐας και αποτελεί τμήμα της Κορινθιακής Τάφρου. Το υπόβαθρο της περιοχής δομείται από τους σχηματισμούς της ζώνης Ωλονού-Πίνδου που έχουν επιφανειακή εμφάνιση σε υψηλότερα υψόμετρα, ενώ το πεδινό τμήμα της περιοχής καλύπτεται Πλειο-Πλειστοκαινικούς και Τεταρτογενής σχηματισμούς. Ο συντελεστής εξατμισοδιαπνοής για την περιοχή έρευνας έχει τιμή 0,77 και το πλεόνασμα νερού εμφανίζεται τους μήνες Ιανουάριο έως Μάρτιο, Νοέμβριο και Δεκέμβριο. Η μεγαλύτερη διακύμανση της στάθμης του υδροφόρου παρατηρείται στα 1,15 (m) και η υδραυλική κλίση που υπολογίστηκε κυμαίνεται από 4‰ ‐6‰. Τέλος τα υπόγεια νερά της περιοχής είναι δυνατόν να ομαδοποιηθούν σε δυο κύριους υδροχημικούς τύπους Ca‐HCO3 και Ca-Mg‐Na‐SO4‐HCO3. / In the frames of this study the climatological data of the broader area of Aigion were collected. Moreover, water level measurements and groundwater sampling has been carried out in order to define the hydrochemical and hydrogeological that prevail in the study area. The water balance of the area was also estimated. The study area is located in Achaia prefecture and consists a part of the Corinth Trench. The bedrock of the study area consists of the formations of Olonos-Pindos zone that out crop in the mountainous part, whereas the Neogene and Quaternary formations cover the lowlands of the study area. The evaporotranspiration coefficient is 0.77 and there is a surplus of water during the periods January-March and November-December. The highest variance of water level of the aquifer was 1.15 (m) and the hydraulic gradient ranges between 4‰ ‐6‰. Finally, the groundwater samples of the study area can be classified into two hydrochemical types Ca‐HCO3 και Ca-Mg‐Na‐SO4‐HCO3.
7

Groundwater Modeling and Hydrogeological Parameter Estimation: Potomac Aquifer System, SWIFT Research Center

Matynowski, Eric D. 29 June 2020 (has links)
The Sustainable Water Interactive for Tomorrow (SWIFT) project in eastern Virginia is a Managed Aquifer Recharge project designed to alleviate the depletion of the Potomac Aquifer System due to unsustainable groundwater withdrawals. At the SWIFT Research Center (SWIFTRC) in Nansemond, VA, a pilot testing well (TW-1) has been implemented to help determine the feasibility of full-scale implementation. The pumping data from TW-1 and observation head data from surrounding monitoring wells (MW) at the SWIFTRC were used to calculate hydrogeological parameters (transmissivity, hydraulic conductivity, specific storage, and storage coefficient). Two sets of data were analyzed from before and after TW-1 was rehabilitated to account for the change in the flow distribution to each screen in TW-1. Comparing the results to past literature, the calculated (Theis and Cooper-Jacob methods) hydraulic conductivity/transmissivity values are within the same order of magnitude. Using borehole logs as well as apparent conductance and resistivity logs, multiple single and multi-layered models for both the upper and middle Potomac aquifers were produced with MODFLOW. Parameter estimation using MODFLOW and PEST and the two sets of observation data resulted in hydrogeological parameters similar to those calculated using Theis and Cooper-Jacob methods. The change in the hydraulic conductivity and specific storage between the pre and post rehabilitation flow distributions is proportional to that change in the flow distribution. For future modeling of the aquifer system, the hydrogeological parameters from the model using the 4/26/19 data set with the post rehabilitation flow distribution is recommended. Drawdown results from a multi-layered MODFLOW model were compared to results using the Theis method using both the Theis-calculated and MODFLOW-PEST modeled hydrogeological parameters. The results were nearly identical except for the Upper Potomac Aquifer (UPA) layer 1, as the model has a large change in aquifer thickness with distance from TW-1 that the Theis-based calculations do not consider. Travel times from the monitoring wells to TW-1 were calculated with the single and multi-layered models pumping 700 GPM from TW-1. Travel times from the SWIFT MW within the UPA sublayers ranged from 204 to 597 days depending on the sublayer, while travel times from the USGS MW within the UPA sublayers ranged from 2,395 to 7,859 days. For the single layer model of the UPA, the travel time from the SWIFT MW to TW-1 was 372 days while the travel time from the USGS MW was 4,839 days. Travel times from the SWIFT MW within the MPA sublayers were 416 and 1,195 days, while travel times from the USGS MW within the MPA sublayers were 4,339 and 11,245 days. For the single layer model of the MPA, the travel time from the SWIFT MW to TW-1 was 743 days while the travel time from the USGS MW was 7,545 days. / Master of Science / The Sustainable Water Interactive for Tomorrow (SWIFT) project in eastern Virginia is a project designed to help slow the depletion of the Potomac Aquifer System due to unsustainable groundwater withdrawals. At the SWIFT Research Center (SWIFTRC) in Nansemond, VA, a testing well (TW-1) has been implemented to help determine if the full-scale implementation of the SWIFT project is feasible. The pumping data from TW-1 and observation head data from surrounding monitoring wells (MW) at the SWIFTRC were used to calculate hydrogeological parameters (transmissivity, hydraulic conductivity, specific storage, and storage coefficients). These parameters help describe the behavior of the aquifer system. Two sets of data were analyzed from before and after TW-1 was rehabilitated to account for the change in the flow distribution within TW-1. Comparing the results to past literature, the calculated (using analytical methods, Theis and Cooper-Jacob methods) hydraulic conductivity/transmissivity values are within the same order of magnitude. Using data from the boreholes, multiple single and multi-layered models for both the upper and middle Potomac aquifers were produced with MODFLOW, a groundwater modeling software. Estimating parameters using observation data within MODFLOW resulted in hydrogeological parameters similar to those calculated using the Theis and Cooper-Jacob methods. The change in the hydraulic conductivity and specific storage between the pre and post rehabilitation flow distributions within TW-1 is proportional to that change in the flow distribution. For future modeling of the aquifer system, the hydrogeological parameters from the model using the 4/26/19 (most recent) data set with the post rehabilitation (more current) flow distribution is recommended. Drawdown (decrease in the water table) results from a multi-layered MODFLOW model were compared to results using the Theis method using both the Theis-calculated and MODFLOW modeled hydrogeological parameters. The results were nearly identical except for the Upper Potomac Aquifer (UPA) layer 1, as the model has a large change in aquifer thickness with distance from TW-1 that the Theis-based calculations do not consider. The time it took for a particle of water to travel from the monitoring wells to TW-1 were calculated with the single and multi-layered models pumping 700 GPM from TW-1. Travel times from the SWIFT MW within the UPA sublayers ranged from 204 to 597 days depending on the sublayer, while travel times from the USGS MW within the UPA sublayers ranged from 2,395 to 7,859 days. For the single layer model of the UPA, the travel time from the SWIFT MW to TW-1 was 372 days while the travel time from the USGS MW was 4,839 days. Travel times from the SWIFT MW within the MPA sublayers were 416 and 1,195 days, while travel times from the USGS MW within the MPA sublayers were 4,339 and 11,245 days. For the single layer model of the MPA, the travel time from the SWIFT MW to TW-1 was 743 days while the travel time from the USGS MW was 7,545 days.
8

Utilização de redes neurais artificiais aplicadas a mapeamentos hidrogeológicos

Reinke, Meriéle 11 March 2008 (has links)
Submitted by Mariana Dornelles Vargas (marianadv) on 2015-03-23T13:17:43Z No. of bitstreams: 1 utilizacao_redes.pdf: 1424216 bytes, checksum: 9225089a71c7a86291b6f821bfe3dca1 (MD5) / Made available in DSpace on 2015-03-23T13:17:43Z (GMT). No. of bitstreams: 1 utilizacao_redes.pdf: 1424216 bytes, checksum: 9225089a71c7a86291b6f821bfe3dca1 (MD5) Previous issue date: 2008 / Nenhuma / A gestão dos recursos hídricos exige o uso de ferramentas que representem os processos hidrológicos de forma clara e objetiva para auxiliar na compreensão e utilização dos mesmos. Atendendo a essa necessidade, desenvolveram-se modelos computacionais que sistematizam problemas complexos de modo simples. Entre esses modelos cita-se a técnica de Redes Neurais Artificiais, metodologia inspirada no sistema nervoso humano e que possui a habilidade de aprender e generalizar possibilitando a resolução de problemas complexos. Neste trabalho é estudada a aplicação de Redes Neurais Artificiais do tipo Percepton Multicamadas baseadas no algoritmo de aprendizado backpropagation para estimar a espessura da Formação Serra Geral, o nível estático e a capacidade específica, baseado em informações contidas no cadastro de poços do Sistema de Informação de Águas Subterrâneas para a Bacia Hidrográfica do Rio Caí no estado do Rio Grande do Sul. Através do teste de Student (teste T), com um nível de significância de 5%, estatisticamente, os modelos propostos para as estimativas da espessura da Formação Serra Geral, do nível estático e da capacidade específica não diferiram dos tomados como verdadeiros. Também, por meio de regressão linear verificou-se através do coeficiente R2 uma forte correlação entre as variáveis simuladas e as verdadeiras. Os resultados indicaram que as RNAs podem ser utilizadas como um método alternativo em relação à modelagem convencional visando a elaboração de cartas temáticas bem como a otimização de processos para a exploração de água subterrânea. / The hydric resources management demands the use of tools that represent the hydrologic processes in a clear and objective way to assist the understanding and using of them. Considering this necessity, computer models that systemize complex problems in a simple way have been developed. Among these models is the Artificial Neural Network technique, a methodology inspired on human nervous system which has the ability to learn and generalize, making possible to solve complex problems. In this work is studied the application of Artificial Neural Networks of Perceptron Multilayer type, based on backpropagation learning algorithmic to estimate the thickness of Serra Geral formation, the static level and specific capacity, based on information extracted from well cadastre of Groundwater Information System for the Hydrographic Basin of Cai River in Rio Grande do Sul state. Through the Student test (test T), with a significance level of 5%, statistically, the models proposed for the estimates of the thickness of Serra Geral Formation, the level static and specific capacity did not differ from taken as true. Also, through linear regression there has been through the coefficient R2 a strong correlation between variables simulated and the real. The results demonstrate that the developed models through the Artificial Neural Networks present good results on prevision of hydrogeologic parameters, which could be used as a base to elaborate thematic maps. In the same way, they suggest the use of alternative data for conventional modeling aiming at processes optimization for groundwater exploration.
9

Ämnestransport med grundvatten i hydrogeologiska typmiljöer

Winnerstam, Björn January 2005 (has links)
<p>Certain types of waste, e.g. bottom ash originating from municipal solid waste incineration (MSWI bottom ash) can be used as road construction materials. A potential problem is the possibility of substances leaching out of the road and spreading in the surrounding groundwater.</p><p>The aim of this master’s thesis is to conclude whether hydrogeological type settings can be employed to, based on local conditions, provide an estimate of the probable spreading of these substances in the surrounding groundwater, and whether certain types of soils can be identified as being less suitable for the localization of a MSWI bottom ash road. A hydrogeological type setting is defined as a mappable unit with similar hydrogeological properties. An advantage of this approach would be that mainly existing maps and surveys could form the basis for the assessment.</p><p>The work has been performed by placing a hypothetical road construction in different hydrogeological type settings. The expected patterns of spreading has then been evaluated using theoretical reasoning and analytical and numerical models.</p><p>The method can be used. In the report various type settings are defined. In several cases further information will be required to render possible a more exact estimate of the spreading. By locating the road on less permeable soils to reduce the local spreading of substances in groundwater, a greater proportion of the water will be drained as surface water. Thus it becomes important to take into account surface water transport aswell. In the report a procedure to estimate the maximum concentrations in groundwater at locations situated downstream the road is presented. This estimate could be used as basis for a more balanced valuation of appropriateness, e.g. by relating the estimated concentrations to background values.</p> / <p>Vissa typer av avfall, exempelvis slaggrus (sorterad bottenaska från avfallsförbränning), kan användas som vägbyggnadsmaterial. Ett potentiellt problem är möjligheten att ämnen lakas ut ur vägen och sprids i omgivande grundvatten.</p><p>Syftet med detta examensarbete är att avgöra om hydrogeologiska typmiljöer kan användas för att, utifrån omgivningens förutsättningar, ge en bild av hur den vidare spridningen av dessa ämnen i omgivande grundvatten sannolikt ser ut, och om vissa typer av mark kan pekas ut som mindre lämpade för lokalisering av en slaggrusväg. En hydrogeologisk typmiljö definieras som ett område möjligt att avgränsa med avseende på karakteristiska hydrogeologiska förhållanden. En fördel med angreppssättet skulle vara att underlagsmaterialet till bedömningen då kan utgöras av i huvudsak befintligt kartmaterial.</p><p>Studien har utförts genom att en hypotetisk vägkonstruktion placerats in i olika hydrogeologiska typmiljöer. De troliga spridningsscenarierna har sedan utvärderats genom teoretiska resonemang, samt genom användande av analytiska och numeriska modeller.</p><p>Metodiken går att använda och i rapporten definieras olika typmiljöer. I flera fall kommer platsspecifik kunskap behöva inhämtas för en närmare beskrivning av spridningsbilden. Genom placering av vägen på tätare mark för att minska lokal spridning av ämnen i grundvatten kommer en större andel av vattnet att avledas som ytvatten. Därmed blir det viktigt att även inhämta kunskap om transport med ytvatten. I rapporten presenteras också en metod för uppskattning av maximala halter i grundvatten nedströms en väg. Denna metod kan användas som underlag för en mer nyanserad värdering av lämplighet, genom att de uppskattade halterna relateras till bakgrundsvärden eller lämpliga riktvärden.</p>
10

Application of Numerical Modeling to Study River Dynamics: Hydro-Geomorphological Evolution Due to Extreme Events in the Sandy River, Oregon

Muhammad, Sarkawt Hamarahim 06 March 2017 (has links)
The Sandy River (OR) is a coastal tributary of the Columbia River and has a steep hydroshed 1316 square kilometers which is located on the western side of Mount Hood (elevation range 3 m to 1800 m). The system exhibits highly variable flow: Its average discharge is ~40 m3/s, and the highest recorded discharge was 1739 m3/s in 1964. In this study I model the geomorphic sensitivity of an 1800m reach located the downstream of the former Marmot Dam, which was removed in 2007. The hydro-geomorphic response to major flood has implications for system management and aquatic life. Studying hydro-geomorphic change requires a systematic approach. Here, I define flows and flood hydrographs for specified return interval based on the observed hydrologic record, and then examine potential hydro-geomorphic changes using a numerical model. A Pearson Type III distribution is used to calculate 100, 75, 50, 25, 10, and 2 year return periods. Extreme event hydrographs are derived by fitting derived and observed flood hydrographs to the gamma distribution curve. Sediment transport and geomorphology are then modeled numerically with Nays2DH, a solver that is part of iRIC software. Because the model is computationally intensive, I model the domain with five different spatial grid resolutions, to find proper grid resolution. The grid resolutions used are 1.5 m, 2 m, 3 m, 4 m, and 5 m. We choose 4 m as optimum grid resolution, based on the convergence of model results. The model is run for extreme event hydrographs with six above return periods. For result visualization and analysis, we focus on flow properties and bed elevation at peak flow and at the end of each event. For both times for each event, important flow and sediment transport parameters are visualized for the entire domain in plane form and eight cross-sections at 200 m intervals. Finally, we divide the geomorphic response into areas of erosion and deposition. Linear regression analyses of mean values of erosion and deposition at peak flow for all extreme events yield R2 of 0.981 for erosion and 0.986 for deposition. The mean erosion and deposition depth at the end of the events is modeled by nonlinear regression with correlation coefficient of 0.965 for erosion and 0.998 for deposition. The regression models provide direct understanding of impacts of different floods on the geomorphic response of the river domain. examination of the model as a whole suggest that the amount of erosion and deposition in the bed and banks is a function of channel geometry, bank and bed geology, riparian area condition and strongly depend on the amount of flow through the channel.

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