Grunts piesārņojuma izpēte, izmantojot radiolokāciju un elektriskās pretestības tomogrāfiju
Loading...
Date
Authors
Advisor
Journal Title
Journal ISSN
Volume Title
Publisher
Latvijas Universitāte
Language
lav
Abstract
Maģistra darbā “Grunts piesārņojuma izpēte, izmantojot radiolokāciju un elektriskās pretestības tomogrāfiju” tiek apvienotas divas ģeofizikālās izpētes metodes – radiolokācija un elektroizpēte, lai veiktu vēsturiskā grunts piesārņojuma ar naftas produktu izpēti, kā arī salīdzināt lauka darbos iegūtos datus ar pieejamo literatūru un agrāk veiktajām izpētēm. Līdzšinējie pētījumi saistībā ar dažādiem naftas produktu piesārņojumiem, galvenokārt, tiek veikti izmantojot lāzer-inducētas fluorescences (LIF) metodi, kā arī veicot urbumus un ievācot gan grunts gan gruntsūdens paraugus. Ņemot vērā, ka gan LIF metode gan urbumu ierīkošana ir invazīva metode (tiek traucēti esošie grunts slāņi), izpētes veicējs tiek pakļauts piesārņojošo produktu klātbūtnei, kas reizēm var būt bīstami veselībai. Izmantojot neinvazīvās metodes - radiolokāciju un elektriskās pretestības tomogrāfiju, šie riski tiek būtiski samazināti. Pētījuma rezultāti sniedz salīdzinošu versiju starp veiktajām ģeofizikālajām metodēm. Izveidotie 2D un 3D modeļi norāda uz lielāku potenciālo piesārņojumu nekā sākotnēji paredzēts. Iegūtie radiolokācijas dati efektīgi norāda zonas ar augstu signāla absorbciju, veidojot tā saucamās ēnu zonas. Izmantojot elektriskās pretestības tomogrāfiju ar dipola-dipola izkārtojumu objektīvi nav iespējams veikt piesārņojuma telpisko izplatību teritorijā, kas saistīts gan ar ogļūdeņražu biodegradācijas stadiju, kas ietekmē to pilnīgu izpēti gan sauso, smilšaino teritorijas virskārtu, kas satur tehnogēnus nogulumus un iespējams rada kļūdainas pretestības datus.
In this master`s thesis: ”The use of ground-penetrating radar and electrical resistivity tomography for investigating soil contamination” two geophysical research methods are combined – ground-penetrating radar and electrical resistivity tomography to conduct historical contamination research of soil contamination with petroleum-based products as well as to compare the data obtained in field with previously conducted studies. Previous studies related to contamination with various petroleum-based products were mainly conducted using laser-induced fluorescence (LIF) method as well as drilling for soil and groundwater samples. Given that both the LIF method and drilling are invasive methods (existing soil layers are disturbed), field technician is exposed to the presence of said petroleum-based products, which can sometimes be hazardous to health. Using non-invasive methods – ground-penetrating radar and electrical resistivity tomography mitigates these risks significantly. The results of the study provide a comparative version between the conducted geophysical methods. The created 2D and 3D models indicate greater potential ground pollution than initially expected. The obtained GPR data effectively indicate areas with high signal absorption, forming so-called shadow zones. When using ERT with dipole-dipole arrangement, it is not possible form an objective standpoint to perform the spatial distribution of pollution in the area due to both the stage of biodegradation of hydrocarbons and the dry, sandy surface layer in area of study, which contains technogenic deposits and creates inaccurate resistivity data.
In this master`s thesis: ”The use of ground-penetrating radar and electrical resistivity tomography for investigating soil contamination” two geophysical research methods are combined – ground-penetrating radar and electrical resistivity tomography to conduct historical contamination research of soil contamination with petroleum-based products as well as to compare the data obtained in field with previously conducted studies. Previous studies related to contamination with various petroleum-based products were mainly conducted using laser-induced fluorescence (LIF) method as well as drilling for soil and groundwater samples. Given that both the LIF method and drilling are invasive methods (existing soil layers are disturbed), field technician is exposed to the presence of said petroleum-based products, which can sometimes be hazardous to health. Using non-invasive methods – ground-penetrating radar and electrical resistivity tomography mitigates these risks significantly. The results of the study provide a comparative version between the conducted geophysical methods. The created 2D and 3D models indicate greater potential ground pollution than initially expected. The obtained GPR data effectively indicate areas with high signal absorption, forming so-called shadow zones. When using ERT with dipole-dipole arrangement, it is not possible form an objective standpoint to perform the spatial distribution of pollution in the area due to both the stage of biodegradation of hydrocarbons and the dry, sandy surface layer in area of study, which contains technogenic deposits and creates inaccurate resistivity data.