Nheyo dzePhysics yePasi muGeophysics
Geophysics ibazi resainzi yepasi rinoongorora Nyika richishandisa misimboti yefizikisi. Kunyange zvazvo geology ichinyanya kuvimba nekucherechedza matombo nezvimiro zviri pamusoro, geophysics "inoona" Nyika nenzira isina kunanga kuburikidza nemhinduro dzemuviri: mafungu, minda inokwevera pasi, magineti, magetsi, kupisa, uye mwaranzi. Nemamwe mashoko, geophysics inotsvaga kupindura mibvunzo yakaita sezviri kuitika pasi pevhu, kuti zvinhu zvayo zvakaita sei, uye kuti ndeapi maitiro ari kuitika—pasina kufanira kuchera kana kuchera kwese kwese.
Kuti tive nechokwadi chekuti tinonzwisisa zvizere nezve geophysics, tinofanira kuongorora misimboti yefizikisi yePasi inotsigira nzira dze geophysical. Misimboti iyi inosanganisira pfungwa dze elastic media, wave propagation, potential fields, electromagnetic induction, heat transfer, uye hukama huripo pakati pehunhu hwezvinhu uye mamiriro e geological.
1. Pasi sehurongwa hwepanyama: maumbirwo, chimiro, uye hunhu hwezvinhu
Panyama, Nyika inogona kufungidzirwa sehurongwa hwakarongwa: goko, mantle, mukati mekunze kwemvura, uye mukati memukati wakasimba. Misiyano iyi yakarongwa haisi kungopatsanurwa kwejeologi, asi inoratidzawo hunhu hwepanyama hwakadai sekuwanda, kusimba, kufambisa magetsi, tembiricha, uye magnetism. Mu geophysics, hunhu hwepanyama uhwu ndihwo "hunhu" hukuru.
Zvinhu zvakasiyana zvinopindura kumasimba nesimba zvakasiyana. Semuenzaniso, matombo ane simba rakawanda anowanzova nehuremu hwakanyanya kupfuura madhaka akareruka; matombo akazara nemvura anotungamira magetsi kupfuura matombo akaoma; uye zvicherwa zvemagineti zvakaita semagnetite zvinopa matombo mukana wekuwana simba remagineti. Kusiyana uku mukupindura kunoita kuti pave nekusanzwisisika kunoyerwa.
2. Simba regiravhiti uye pfungwa yemunda unogona kusvikwa
Imwe yenheyo huru dzefizikisi yePasi igravity. Simba regravity rePasi harina kufanana nekuda kwekupararira kwehukuru hwakasiyana. Matombo ane density yakawanda "anodhonza" zvakasimba kupfuura matombo asina density yakawanda. Gravitational geophysics inoshandisa misiyano midiki mukukurumidzisa gravity (gravity anomalies) kutsanangura maumbirwo ari pasi pevhu.
Panyaya yemasvomhu, simba rinokwevera pasi isimba rinogona kuwanikwa kubva pabasa rinogona kuwanikwa uye rinogutsa Laplace/Poisson equation pasi pemamwe mamiriro ezvinhu. Izvi zvakakosha nekuti nzira dzakawanda dze geophysical—simba rinokwevera pasi uye simba remagineti—dzine hunhu husina kujairika: pateni imwe chete inogona kukonzerwa nemaitiro akasiyana-siyana epasi pevhu. Nokudaro, kududzira kunoda zvimwe zvirambidzo zvakaita sedata re geological, data re seismic, kana ruzivo rwekubhoboza.
Mashandisirwo ayo anosanganisira kugadzira mapu emabheseni emvura, kuona madome emunyu, uye kudzidza isostasy (kuenzana kwehuwandu hwe lithosphere kana tichienzanisa ne mantle). Nheyo ye isostasy inotsanangura kuti sei makomo aine "midzi" yakareruka kana kuti yakakora, zvichiita kuti akwanise kuyerera kana tichienzanisa ne mantle.
3. Simba remagineti rePasi: minda yemagineti uye manyuko ekusarongeka kwemagineti
Nyika ine simba guru remagineti rinobva mukusimba kwemvura iri mukati mayo (geodynamo). Pamusoro pesimba guru, kunewo simba remagineti remunharaunda rinobva mumatombo ane magineti. Magnetic geophysics inoyera kusiyana kwesimba remagineti kuti iongorore maumbirwo egeologi, kunyanya ayo ane chekuita nematombo ane magineti akawanda uye ane metamorphic.
Pfungwa huru pano ndeyekuti magnetization yematombo ine zvikamu zviviri: induced magnetization (yakafanana ne Earth's current magnetic field) uye remanent magnetization (yakasara ye magnetization yekare, apo dombo rakaumbwa). Remanent magnetization inobatsira zvikuru mu paleomagnetism pakuvakazve kufamba kwema tectonic plates uye nhoroondo ye Earth's magnetic pole reversals.
Pachikero chenzvimbo, ruzivo rwemagineti runobatsira kuyera pasi pevhu (pasi pematombo) pasi pejecha gobvu, kutevedzera zvikanganiso, uye kuongorora zvicherwa.
4. Mafungu epasi uye kusimba kwepakati
Nheyo huru yefizikisi mu geophysics ndeye mafungu emagetsi mu elastic media. Nzira dzeSeismic dzinoshandisa mafungu e elastic anopararira nePasi. Kune mhando mbiri huru dzemafungu mukati mePasi: maP-waves (ekutanga, enguva refu) uye maS-waves (echipiri, echitenderera). MaP-waves anogona kupararira muzvinhu zvakasimba uye zvine mvura, nepo maS-waves asingakwanise kupararira mumvura. Ichi chiitiko chepanyama chikonzero chakakosha nei tichiziva kuti mukati mePasi mvura: maS-waves haagone kupfuura nepakati pawo.
Kumhanya kwemafungu epasi pevhu kunoenderana ne elastic moduli uye density yezvinhu. Zvichitaurwa zviri nyore, matombo akaomarara uye akasimba anowanzova nekumhanya kwemafungu kwakakwira. Kana mafungu achipfuura nepakati pezvikamu zvine hunhu hwakasiyana, kuratidzwa uye kudzorwa kunoitika, zvichitevera misimboti yakafanana nemutemo waSnell mu optics. Kubva panguva yekufamba kwemafungu, amplitude, uye waveform, nyanzvi dze geophysicists dzinogona kufungidzira kudzika kwezvikamu, ukobvu hwe sediment, uye kunyange kuvapo kwemvura.
Nyanzvi dzezvekudengenyeka kwenyika dzinoongorora kudengenyeka kwenyika kuti dziongorore chimiro cheganda repasi nepakati, ukuwo nyanzvi dzezvekudengenyeka kwenyika dzichiongorora nzvimbo dzinochengeterwa mafuta, gasi, uye mvura inopisa pasi pevhu.
5. Magetsi nemagetsi: kufambisa simba, kudzima simba, uye kupinza simba
Maitiro mazhinji epasi pevhu anosanganisira mvura, mineralization, uye kusiyana kwekupisa—zvose zvinokanganisa conductivity yemagetsi. Nheyo huru yenzira dzemagetsi neelectromagnetic ihukama huripo pakati pemagetsi emagetsi, simba remagetsi, uye hunhu hwechinhu chiri mukati, chinowanzo tsanangurwa nemutemo waOhm muchimiro chinoenderera mberi (J = σE), σ ichiva conductivity.
Kuramba, kupokana kwakakonzerwa (IP), magnetotelluric (MT), nedzimwe nzira dzemagetsi dzinoyera mhinduro yepasi pevhu kuzvinhu zviripo/nzvimbo, zvese zvekugadzira uye zvechisikigo. Nheyo ye electromagnetic induction—yakaumbwa mumutemo waFaraday—inotsanangura kuti kuchinja kweminda yemagineti kunogadzira sei minda yemagetsi uye eddy currents muvhu. Aya eddy currents anobva agadzira secondary magnetic fields inoyerwa pamusoro.
Zvinhu zvakazadzwa nemvura ine munyu zvinofambisa mvura zvakanyanya; ivhu rinowanzo fambisa mvura nekuda kwenzira dzinofambisa mvura pamusoro. Kusiyana neizvi, matombo akaoma ekristaro nemahydrocarbon anowanzo dzivirira mvura. Nokudaro, nzira dzeEM dzinoshandiswa zvakanyanya pakutsvaga mvura yepasi pevhu, geothermal, sulfide mineral, uye kudzidza nzvimbo dzine mvura dzakazadzwa nemvura.
6. Kutamiswa kwemhepo inopisa uye kupisa: kutungamirwa kwemhepo uye kutenderera kwemhepo
Nyika haina kumira zvakanaka; inoyerera simba rekupisa kubva mukati kuenda pamusoro. Nheyo dzekufambisa kupisa dzinosanganisira kutenderera (kuyerera kwekupisa kuburikidza nezvinhu zvisina kutamiswa zvakanyanya) uye convection (kuyerera kwekupisa kunoperekedzwa nekutamiswa kukuru, senge mantle inoyerera zvishoma nezvishoma). Mutemo waFourier unotsanangura kuyerera kwekupisa kunofambisa mhepo sekwakaenzana nekupisa kwakanyanya uye kutenderera kwekupisa.
Kuyerwa kwemafuta anodziya, kupisa, uye hunhu hwekupisa hwematombo kunobatsira kunzwisisa masisitimu emvura inopisa, metamorphism, uye tectonic dynamics. Semuenzaniso, munzvimbo dzinopisa, maitiro ekupisa anokanganiswa nemapuleti anodziya, kutenderera kwemvura, uye kukweshana panzvimbo yekubatana. Pamakomo ari pakati pegungwa, kukwira kwechinhu chinopisa kunowedzera kupisa uye kunogadzira masisitimu emvura inopisa.
7. Hukama huripo pakati pezvinhu zvemuviri nekududzirwa: dambudziko rekuchinja-chinja uye kusasiyana
Chinangwa che geophysics hachisi chekuyera chete, asi kududzira. Kuyera pamusoro kana kubva mumhepo kana kubva kunobva satellite kunofanirwa kushandurwa kuita mamodheru ari pasi pevhu. Maitiro aya anonzi inversion. Panyaya yemuviri uye yemasvomhu, inversions kazhinji hadzisi dzakasiyana: mamodheru akawanda anogona kutsanangura data rimwe chete. Nokudaro, geophysics yemazuva ano inovimba nemisimboti yekudzoreredza, nhamba, uye kubatanidzwa kwedata rakawanda.
Semuenzaniso, kusagadzikana kwegiravhiti kunogona kuratidza kuvapo kwemuviri une density yakakura, asi hazviratidzi zvakananga kuti ingava basalt intrusion kana metal ore - zvese zvinogoneka. Nekuwedzera data remagineti, seismic, kana EM, dudziro inova yakasimba uye yechokwadi.
8. Chiyero nechinangwa: kubva pakutsvaga kusvika pakunzwisisa pasi rose
Nheyo dzefizikisi yePasi mu geophysics dzinoshanda muzvikamu zvakasiyana-siyana. Pachiyero chepasi rose, satellite seismology uye gravity zvinobatsira kuona kusiyana kwenzvimbo yepasi, geoid, uye kutenderera kwemukati. Pachiyero chedunhu neremunharaunda, nzira dze geophysical dzinoshandiswa pakutsvaga zviwanikwa (oiri, gasi, zvicherwa, geothermal), kuderedza njodzi (kutarisa makomo anoputika, microzonation yekudengenyeka kwenyika), geotechnical engineering (kugadzikana kwenheyo), uye zvidzidzo zvezvakatipoteredza (kusvibiswa kwevhu nemvura).
Chinobatanidza zvese izvi ipfungwa yekuti kusiyana kwezvinhu zvemuviri—kuwanda, kuchinjika, kutenderera, kugona kushandisa simba remagetsi, uye tembiricha—zvakabatana zvakananga nemaitiro egeologi. Nzira dzegeophysical dzinopa mukana wekuona kusiyana uku nehuwandu.
Penutup
Nheyo huru dzefizikisi yePasi mu geophysics dzinogona kupfupikiswa sekuyedza kunzwisisa Pasi kuburikidza nemhinduro dzemuviri dzinoyerwa: simba rinokwevera pasi nemagnetism senzvimbo dzinogona kuganhurirwa, seismic se elastic wave propagation, nzira dzemagetsi ne electromagnetic se conductivity uye induction responses, uye geothermal se internal heat flow. Nzira yega yega ine simba nemiganhu, kunyanya ine chekuita nekusasiyana kwekududzira, saka kubatanidzwa kwedata nekunzwisisa fizikisi yezvinhu zvakakosha.
Nehwaro hwakasimba mufizikisi, geophysics inogona kubatanidza kucherechedza pamusoro nehupenyu hwakaoma huri pasi apa—kubatsira vanhu kunzwisisa chimiro cheNyika, kushandisa zviwanikwa zvayo zvakakodzera, uye kuderedza njodzi dzenjodzi kuburikidza nekugadzira modeling uye kutarisa zviri nani.
