Ukuqonda Okuyisisekelo Indlela Yokumelana Ne-Electromagnetic
Indlela yokumelana nogesi iyindlela esetshenziswa kabanzi yokuhlola izimo zangaphansi komhlaba ngaphandle kwesidingo sokumba. Le ndlela isebenza ngokusebenzisa impendulo yedwala noma inhlabathi kumandla kagesi kanye namasimu kagesi. Empeleni, le ndlela iwusizo kakhulu ezidingweni ezahlukahlukene, njengokuhlola amanzi angaphansi komhlaba, uphenyo lwamaminerali, izifundo zokungcoliswa kwemvelo, kanye nokunquma izici zobunjiniyela be-geological zamaphrojekthi engqalasizinda. Ukuze uqonde le ndlela kahle, kubalulekile ukuqonda imiqondo eyisisekelo yokumelana nogesi, ubudlelwano phakathi kwezinto zamandla kagesi nezinto zangaphansi komhlaba, kanye nendlela izilinganiso ezenziwa ngayo ensimini.
Umqondo Wokumelana Nokuqhutshwa Kwezinto Ezithile
Ukumelana kuyisilinganiso sokuthi into ethile ivimbela kangakanani ukugeleza kwamandla kagesi. Ukumelana ngokuvamile kufanekiselwa yi-ρ (rho) futhi kunamayunithi e-ohm-meters (Ωm). Ukuhambisana kwayo kuwukuqhutshwa kwamandla kagesi (σ), okubonisa ikhono lento ethile lokuqhuba ugesi, ngamayunithi e-siemens ngemitha (S/m). Kalula nje, izinto ezinokumelana okuphezulu zivame ukuba nzima ukuqhuba amandla kagesi (isibonelo, idwala eliyi-igneous elomile), kuyilapho izinto ezinokumelana okuphansi zivame ukuba lula ukuqhuba amandla kagesi (isibonelo, ubumba olugcwele amanzi anosawoti).
Esimweni se-geological, ukumelana akunqunywa nje kuphela ngohlobo lwedwala, kodwa futhi nangama-porosity, okuqukethwe kwamanzi, izinga lokugcwala, usawoti we-pore fluid, izinga lokushisa, kanye nokuqukethwe kwamaminerali aqhubayo (njenge-graphite noma i-sulfide). Ngenxa yokuthi izici eziningi zithonya amanani okumelana, ukuchazwa kwedatha kufanele kucabangele njalo izimo ze-geological zendawo.
Indlela Eyisisekelo Yokumelana Ne-Electromagnetic
Igama elithi "ukumelana ne-electromagnetic" livame ukusetshenziswa ukubhekisela kumasu kagesi ahlose ukunciphisa ukuguquguquka kokumelana ne-subsurface. Isimiso esiyisisekelo yilesi: lapho insimu ye-electromagnetic ishintsha ngokuhamba kwesikhathi, ibangela imisinga kagesi enhlabathini (imisinga ye-eddy). Le misinga ye-eddy ibe isikhiqiza insimu yesibili yamagnetic engalinganiswa ngamathuluzi. Ngenxa yokuthi amandla kagesi abangelwayo ancike ekuqhubeni (noma ekumelaneni) kwe-medium, impendulo eqoshiwe ingasetshenziswa ukulinganisa izakhiwo zikagesi ze-subsurface.
Ngokungafani nendlela ye-DC resistivity geoelectric, efaka ugesi ngqo ngama-electrode, indlela ye-electromagnetic isebenzisa ukungeniswa kwe-electromagnetic—ngokuvamile ngaphandle kokuxhumana ngqo nomhlabathi (noma ngokuxhumana okuncane). Lokhu kuyinzuzo enkulu lapho uhlola ezindaweni ezinamatshe, ezigandayiwe, noma ezindaweni lapho ukufakwa kwe-electrode kunzima khona.
Isimiso Sokungeniswa Kwe-Electromagnetic
Ukufakwa kwe-electromagnetic kusekelwe emthethweni kaFaraday, othi ukushintsha i-magnetic flux kukhiqiza amandla e-electromotive (EMF), abese ekhiqiza ugesi. Ezifundweni ze-EM, izinsimbi zivame ukuba ne-transmitter ekhiqiza insimu yamagnetic eyinhloko. Le nsimu eyinhloko ingena emhlabathini, ibangele ugesi obangelwayo. Ugesi obangelwayo ube usudala insimu yamagnetic yesibili etholwa yi-receiver.
Umamukeli angalinganisa ubukhulu bensimu, isigaba (ukushintsha kwesigaba phakathi kwezibonakaliso eziyinhloko nezesibili), noma kokubili. Lolu lwazi lobukhulu kanye nesigaba lube selucutshungulwa lube yimingcele efana nokuqhuba okubonakalayo noma ukumelana okubonakalayo. Lawa manani abizwa ngokuthi "asobala" ngoba amelela isilinganiso esihlanganisiwe kulo lonke ivolumu engaphansi komhlaba, ethonywe ukujula kokungena kwesignali, kunokuba kube yinani elimsulwa endaweni eyodwa.
Ukujula Kokungena Nokujula Kwesikhumba
Umqondo obalulekile ezindleleni ze-electromagnetic ukujula kokungena kwesignali, okuvame ukubizwa ngokuthi "ukujula kwesikhumba." Ukujula kwesikhumba ukujula okuphawulekayo lapho ubukhulu begagasi le-electromagnetic buncipha khona kakhulu (ngokuvamile kufika ku-37% wenani lalo lokuqala). Ukujula kwesikhumba kuthonywa ukumelana kwe-medium, imvamisa yesignali, kanye nokuvuleka kwamagnetic.
Ngokwekhwalithi, amaza aphansi avame ukungena ngokujulile, kuyilapho amaza aphezulu ezwela kakhulu ezingqimbeni ezingajulile. Ngokufanayo, i-medium evimbelayo kakhulu ivumela ukungena okujulile kune-medium eqhubayo. Ngakho-ke, ukukhethwa kwamaza ocwaningweni lwe-EM kuyisu elibalulekile lokuqinisekisa ukuthi amatshe ahlosiwe—njengezimila zamanzi, izindawo ezigugile, noma imizimba yamaminerali—angatholakala ekujuleni okufanele.
Izinhlobo Ezivamile Zezindlela Zama-Electromagnetic
Kunezinhlobo eziningana zezindlela ze-electromagnetic ezisetshenziswa ocwaningweni lokumelana ne-subsurface:
1. I-Frequency Domain Electromagnetic (FDEM)
Le ndlela isebenzisa izimpawu ze-sinusoidal ngemvamisa eyodwa noma ngaphezulu. Amathuluzi e-FDEM avame ukusetshenziselwa ukumaka ngokushesha ukuhanjiswa kwe-shallow conduction, isibonelo, ezifundweni zokungcola, ukumaka ubumba, noma ukuhlola kwezolimo. Idatha ye-FDEM ngokuvamile ifaka izingxenye zesigaba kanye ne-quadrature ezihlobene nezakhiwo zokuhambisa kanye nezama-magnetic ze-medium.
2. I-Time Domain Electromagnetic (TDEM)
Le ndlela isebenzisa i-pulse yamanje eya ku-transmitter bese ibona ukubola kwensimu yesibili ngemva kokuba i-transmitter icishiwe. Ulwazi lwesikhathi sokubola luhlobene nokusatshalaliswa kokumelana nokujula. I-TDEM ifaneleka ekuhlolweni okujulile kune-FDEM, njengokuhlola okujulile kwamanzi angaphansi komhlaba noma uphenyo lwe-geothermal.
3. I-Magnetotelluric (MT)
I-MT isebenzisa imithombo yemvelo yokwehluka kwensimu kagesi kusuka emkhathini kanye nokusebenzisana kwelanga nomhlaba. Le ndlela inamandla okutadisha isakhiwo songqimba loMhlaba ekujuleni okukhulu, okwenza isetshenziswe njalo ekuhloleni komhlaba kanye nasezifundweni ze-tectonic. Ukuhlukahluka kwemvamisa yemvelo kuvumela ukuxazululwa kusukela ekujuleni kuya ekujuleni kakhulu.
Nakuba lezi zindlela ezintathu zihlukile ngokwemithombo kanye nezindlela zokulinganisa, umgomo wokugcina uyafana: ukuthola imodeli yokumelana ne-subsurface.
Izigaba Zokuhlola: Ukuthola Ukuhumusha
Ucwaningo lokumelana nogesi ngokuvamile luhilela izigaba eziningana. Esokuqala ukuhlela: ukunquma izinhloso, ukujula kwezinhloso, kanye nezimo zensimu, kanye nokukhetha izindlela ezifanele kanye nokucushwa kwemishini. Esesibili ukutholwa kwedatha ensimini kusetshenziswa iphuzu elithile noma iphethini yomzila. Kulesi sigaba, ukulawulwa kwekhwalithi kubalulekile, njengokuphindaphinda izilinganiso, ukuqaphela ukuphazamiseka kwamasiko (izintambo zikagesi, uthango, amapayipi ensimbi), kanye nokulungiswa kwezindawo.
Isigaba esilandelayo ukucubungula idatha, okuhlanganisa ukususwa komsindo, ukulungiswa kokukhukhuleka, ukuguqulwa kwedatha ibe amapharamitha e-pseudo, kanye nokukhiqizwa kwesigaba noma imephu. Ngemuva kwalokho, ukuguqulwa kwenziwa ukuguqula idatha yokulinganisa ibe yimodeli yokumelana ne-subsurface ehambisana nedatha. Ukuguqulwa ngokuvamile kukhiqiza imodeli ye-1D (eqondile), i-2D (engxenyeni enqamulayo), noma i-3D (ivolumu), kuye ngenani lamaphasi kanye nobunzima bethagethi.
Incazelo yokugcina akufanele izimele yodwa. Imodeli yokumelana izoba nenjongo kakhulu uma ihlanganiswa nedatha esekelayo efana ne-surface geology, idatha yokubhoboza, izilinganiso ze-geochemical, noma ezinye izindlela ze-geophysical (isb., i-seismic noma i-gravity). Ukumelana okuphezulu kungabonisa idwala eliqinile elomile, kodwa kungabonisa nesihlabathi esomile; ukumelana okuphansi kungabonisa ubumba, amanzi anosawoti, noma ukumbiwa okuthile. Umongo we-geological unquma incazelo yawo yangempela.
Izinzuzo kanye nokulinganiselwa
Izinzuzo zendlela yokumelana nogesi zihlanganisa isivinini sokuhlola, ikhono lokusebenza ngaphandle kokuxhumana kwe-electrode, kanye nokuzwela okuhle ezinguqukweni zokuqhuba okubangelwa uketshezi noma amaminerali okuqhuba. Le ndlela futhi isebenza kahle ekumepheni izindawo ezinkulu.
Kodwa-ke, kunemikhawulo okumele iqondwe. Okokuqala, idatha ye-EM isengozini yokuphazamiseka okuvela engqalasizinda yabantu njengezintambo zikagesi, izitimela, izimoto, kanye nezakhiwo zensimbi. Okwesibili, ukuhumusha kungaba okungaqondakali uma kungasekelwa ulwazi lwe-geological. Okwesithathu, ezindabeni ezisebenzisa kakhulu amandla okuhambisa, ukujula kokungena kulinganiselwe, okwenza kube nzima ukuthola izinhloso ezijulile. Ngakho-ke, ukukhetha indlela, ukwakheka kocwaningo, kanye nokuhlanganiswa kwedatha kuyisihluthulelo sempumelelo.
I-Penutup
Ukuqonda okuyisisekelo kwezindlela zokumelana nogesi kuvela emiqondweni yokumelana nogesi kanye nokungeniswa kogesi. Ngokubheka impendulo yensimu yesibili ngenxa yemisinga ebangelwa yizinhlayiya ezingaphansi komhlaba, singalinganisa ukuhlukahluka kokumelana okuhlobene ne-lithology, okuqukethwe koketshezi, kanye nesakhiwo se-geological. Izindlela ezahlukahlukene—i-FDEM, i-TDEM, kanye ne-MT—zinikeza ukuguquguquka kusukela ophenyweni olungajulile kuya kolujulile kakhulu. Naphezu kwezinselele ezifana nomsindo wamasiko kanye nokungacaci kokuhumusha, lezi zindlela zihlala zimathuluzi abalulekile ku-geophysics esetshenziswayo ngenxa yekhono lazo lokumaka indawo engaphansi komhlaba ngokushesha, ngokungabhubhisi, nangokunolwazi. Uma zaklanywa futhi zihunyushwa kahle, izindlela zokumelana nogesi zingenza iminikelo ebalulekile ekuhlolweni kwezinsiza, ekunciphiseni imvelo, kanye nokuhlela intuthuko.
