Ariā Taketake me te Whakamahinga o te Tomography Ru
Ko te tomography ru whenua he tikanga matawhenua e whakamahia ana hei "whakaahua" i te roto o te Ao mā te whakamahi i ngā ngaru ru whenua. He rite tonu ki te matawai CT i roto i te rongoā, e hanga ana i tētahi whakaahua toru-ahu o te tinana mai i ngā hihi-X, ka whakatauirahia e te tomography ru whenua ngā hanganga o raro i te mata mā te whakamahi i ngā raraunga mō te wā haere, te kaha, ngā āhua ngaru rānei i tuhia e tētahi whatunga o ngā mita ru whenua. He mea nui tēnei tikanga nā te mea kāore e taea te tirotiro tika i te roto o te Ao, engari ko ngā āhuatanga pēnei i te tectonics pereti, te ngohe puia, me ngā rū whenua he nui te awe o ngā rerekētanga o ngā āhuatanga ā-tinana o ngā toka i te hohonutanga.
1. Te Ariā Taketake o ngā Ngaru Ru
He ngaru pīngore ngā ngaru rū whenua e horapa ana i roto i te toka. Ko ngā ngaru rū whenua ka wehea whānuitia kia:
1. Ngā ngaru tinana
– Ngā ngaru P (tuatahi/pēhanga): te tere rawa o te horapa, ka taea te haere i roto i ngā totoka me ngā wai, he tairongo ki ngā panonitanga o te tere pēhanga me te mātotoru.
– Ngā ngaru S (tuarua/kutikuti): he puhoi ake i te P, kāore e taea te horapa i roto i ngā wai, he tairongo ki te pakari (te modulus kutikuti) o te toka.
2. Ngā ngaru mata
Hei tauira, ko ngā ngaru Rayleigh me Love, e kaha ana i roto i ngā rekoata rū whenua i tawhiti, he marara, ā, he tino whai kōrero mō te hanganga o te lithosphere tae noa ki te asthenosphere pāpaku.
Ko te tere o ngā ngaru rū whenua e whakawhirinaki ana ki ngā tawhā elastic (modulus) me te mātotoru. Ka pāngia te tere e ngā rerekētanga o te pāmahana, te hanganga kohuke, te pēhanga, te porosity, ngā pakaru, me te aroaro o ngā wai, o ngā rewa wāhanga rānei. Koinei te pūtake ā-tinana mō te mahere i ngā rerekētanga tere hei whakarato tohu mō ngā āhuatanga whenua o raro i te mata.
2. Ngā Mātāpono o te Tomography: Te Raru Whakamua me te Raru Whakamuri
E tū ana te tomography rū whenua i runga i ngā ariā tatau e rua:
a) Raru whakamua (raru whakamua)
Mēnā ka hoatu he tauira o te Ao (hei tauira, he tohatoha tere o te ngaru), ka taea e tātou te tatau i tētahi matapae o ngā raraunga ru whenua: te wā haere o tētahi ngaru mai i tētahi pūtake (rū whenua, pūtake horihori rānei) ki tētahi teihana. I roto i tētahi huarahi ariā hihi māmā, ka whakaarohia te ara ngaru he hihi e whai ana i te mātāpono a Fermat: ka whiriwhiria e te ngaru te ara me te wā haere iti rawa.
Ka taea te tuhi i te wā haere \(T\) mā te pāngarau penei:
\[
T = \int_{\text{ray}} \frac{ds}{v(\mathbf{x})}
\]
ko \(v(\mathbf{x})\) te tere o te ngaru i te tūranga \(\mathbf{x}\), ā, ko \(ds\) te huānga roa o te ara.
b) Raru whakamuri
Ko te ritenga kē tēnei: kei a tātou ngā raraunga tirotiro (ngā wā haere, ngā toenga wā haere, ngā mararatanga ngaru mata, ngā āhua ngaru rānei) ā, e hiahia ana tātou ki te whakatau tata i te tauira tere tino pai. Ko te raruraru whakahurihuri he mea kāore i te ahurei, ā, he hē te whakatakoto: ka taea e ngā tauira maha te urutau ōrite, ā, kei roto i ngā raraunga te koretake/haruru. Nō reira, me whakarite kia rite, pērā i te whakangawari, te whakaiti, ngā herenga whenua rānei.
I roto i te mahi, he maha ngā wā ka mahia te hurihanga i roto i te tikanga whakarārangi: ka paku whakakorikoria te tauira tuatahi, kātahi ka tatauhia te rerekētanga o te wā haere penei:
\[
\delta T \approx \int_{\text{ray}} \delta s(\mathbf{x})\, ds
\]
ko te \(\delta s = \delta(1/v)\) te whakararuraru puhoi. Kua whakaritea ēnei whārite ki roto i tētahi pūnaha rārangi nui \( \mathbf{d} = \mathbf{Gm} \), kātahi ka whakatauhia mā te tikanga tapawhā iti rawa kua whakamaroketia, mā ōna rerekētanga rānei.
3. Ngā momo Tomography Ru
1) Tomography wā-haere
Ko te tikanga tino noa ko te whakamahi i ngā taenga mai o te āhua-P me te āhua-S mai i ngā rū whenua maha. Ko ngā raraunga he toenga wā haere ki tētahi tauira tohutoro (hei tauira, IASP91, ak135 rānei i te tauine ā-ao). He pai mō te whakatauira tere 3D i roto i te kirinuku me te papa o runga, inā koa he kikī te whatunga teihana.
2) Tomography ngaru-mata
Mā te whakamahi i te mararatanga (te huringa o te tere ā-wāhanga/rōpū me te wā) o ngā ngaru Rayleigh/Love. He tairongo ki ngā hanganga papaku ki waenga, he tino whai hua tēnei tomography mō te mahere i te matotoru o te lithospheric, ngā rohe tere-iti (LVZ), me ngā rerekētanga pāmahana.
3) Tomography rū nui (tomography rū nui)
Mā te whakamahi i ngā rū whenua tawhiti (teleseismic) e haere ana ngā ngaru mā roto i te mantle, kātahi ka hopukina e te whatunga ā-rohe. Ko te painga: he maha ngā pūtake, ā, e ahu mai ana i ngā ahunga rerekē, ā, ka āwhina i te "whakamārama" i te rahinga o raro i te mata o te rohe rangahau, hei tauira i raro i ngā puia, i ngā rohe ruku rānei.
4) Tātaritanga āhua ngaru / hurihanga āhua ngaru katoa (FWI)
Mā te whakamahi i te āhua ngaru katoa, ehara i te wā taenga anake, ka puta he taumira teitei nā te mea ka whakamahia katoatia ngā mōhiohio whānui me te āhua, engari me nui ngā whakaritenga rorohiko me te tauira tīmatanga pai hei karo i ngā mahanga iti rawa o te rohe.
4. Ngā Wāhanga Whānui o te Tukatuka me te Hurihuri
1. Te kohikohi raraunga
He kohinga o ngā rekoata mai i ngā ine ru whenua tūturu, rangitahi rānei. I runga i te tauine tūhuratanga, ko te pūtake pea he pahūtanga, he wiri rānei; i runga i te tauine rohe-ao whānui, ko te pūtake matua he rū whenua.
2. Te tautuhi me te kōwhiri i ngā wāhanga
Te whakatau i te wā taenga mai o ngā ngaru P, S, ngā ngaru mata rānei. Ko te kounga o te kohi ka whakatau i te kounga o te tauira.
3. Te whakatikatika tuatahi me te whakatauira
Te whakatikatika wā (te nekenekehanga karaka), te whakatikatika teitei, me te kōwhiringa tauira tohutoro. Ka taea te tauira tuatahi te 1D, te 3D noa rānei.
4. Te whai i te hihi / te whakatauira ngaru
Tātaihia te ara o ngā hihi hangai, o ngā ngaru rānei hei hanga i te matihiko aro.
5. Hurihuri me te whakatikatika
Te whakaoti rapanga i te pūnaha hei whiwhi i tētahi tauira tere. Ka whiriwhiria te whakatikatika i runga i te whāinga: mēnā ka whakamāramahia ngā āhuatanga rerekē koi, ngā ia maeneene rānei.
6. Aromatawai whakataunga me te whakamātautau pono
Hei tauira, mā te whakamātautau papa tirotiro, te whakamātautau pūwero, te tātari mahi tauwhitinga/horapa tohu rānei hei kite ko ēhea ngā wāhanga e tino whakatauhia ana e te raraunga.
5. Te Whakamārama i te Tauira Tere
Ko te hua o te tātaitanga irahiko he mahere o ngā rerekētanga tere whanaunga: ko ngā rohe tere-teitei ka whakamāramatia he toka mātao ake, he toka kiato ake, he toka pakari ake rānei (hei tauira, he papa e heke ana). Ka taea e ngā rohe tere-iti te tohu i ngā pāmahana teitei, i ngā toka kua whakarerekētia, i ngā rohe pakaru kī tonu i te wai, i te rewa wāhanga rānei—he maha ngā wā e hono ana ki ngā puia hohe, ki te asthenosphere wera rānei.
Heoi, me tūpato te whakamaoritanga nā te mea he maha ngā āhuatanga e pāngia ai te tere. Ko te mea pai, me whakakotahi te tomography ru whenua me ētahi atu raraunga pēnei i te kaha ā-papa, te magnetotelluric (MT), te geodesy, te geology mata, me te petrolology.
6. Ngā tono Tomography Ru
a) Te ako i ngā rohe toremi me ngā nekehanga pereti
Ka taea e te tātaitanga ā-ao me ā-rohe te mahere i te papa e heke ana i te mantle, tae atu ki tōna āhuahanga, te hohonutanga, me te wehewehenga. He mea nui ēnei mōhiohio hei mārama ki ngā pūtake o ngā rū whenua nui, ngā tikanga hononga pereti, me te whanaketanga tectonic o tētahi rohe.
b) Ngā pūnaha puia me te whakaiti i ngā āhuatanga kino
I ngā wāhi puia, ka taea e te tātaitanga whakaahua te tautuhi i ngā rohe tere-iti e pā ana ki ngā rūma magma, ngā ara wai e piki ake ana, ngā toka kua whakarerekētia rānei. Mā te aroturukitanga auau, ka taea e ngā huringa tere (tātaitanga whakaahua wā-roa) te whakarato tohu mō te nekehanga wai/magma e tika ana mō te whakatūpato wawe o te pahūtanga.
c) Te tūhuratanga pūngao me ngā rauemi
I te tauine papaku o te kiripaka, ka whakamahia te tomography i roto i te tūhuratanga warowaihā, te waiariki, me te keri. Ka āwhina ngā rerekētanga tere ki te mahere i te hanganga o ngā kohatu, ngā hanganga hapa, ngā rohe pakaru, me ngā puna wai. I roto i te waiariki, he maha ngā wā ka whai hua te whakaurunga o te tomography me te MT: ka whakaratohia e te tomography ngā mōhiohio elasticity, ka whakaratohia e te MT ngā mōhiohio e pā ana ki te kawe wai.
d) Te whakaahuatanga o ngā hapa hohe me ngā tūponotanga rū whenua
Ka taea e te tākuta ā-rohe te whakaatu i ngā rohe ngoikore, ngā rohe kino, me te rerekētanga huri noa i ngā hapa. Mā tēnei ka āwhina i te mārama ki te wehewehenga hapa, te raka pea, me ngā rerekētanga tere e pā ana ki te whakanui i te ngaru (ngā pānga o te pae).
e) Te hanganga o te kiripaka rohe me te hanganga o te lithosphere
Mā te whakamahi i te tomography ngaru mata, ka taea e ngā kairangahau te mahere i te matotoru o te lithospheric, te rohe Moho, me ngā āhuatanga rerekē o te asthenospheric. Ko ngā hua te pūtake mō ngā tauira geodynamic, tae atu ki te hanganga o te puna, te orogenesis, me te whanaketanga o te whenua.
7. Ngā Here me ngā Wero
He tino whakawhirinaki te tomography rū whenua ki te tohatoha o ngā pūtake me ngā teihana. Ko ngā wāhi he iti noa ngā rū whenua, he iti rānei ngā teihana ka iti te māramatanga, ka iti te taumira. Hei tāpiri, ko ngā whakaaro ariā hihi ka iti ake te tika mō te rerekētanga kaha, mō ētahi auau rānei. Ka pā anō hoki te haruru, ngā hapa kōwhiri, me te koretake o te taunga o te hypocenter ki ngā hua hurihuri. Nō reira, he mea nui te aromatawai taumira me te whakauru maha-tikanga hei karo i te whakamaoritanga nui rawa.
Te Katinga
He taputapu matua te tātaitanga ru whenua mō te tirotiro i te hanganga o roto o te Ao mai i te rohe ki te ao whānui. Ko tōna pūtake ariā e whakawhirinaki ana ki te whanaungatanga i waenga i ngā āhuatanga rapa o te toka me te horapa o te ngaru, tae atu ki te whakaoti rapanga whakamuri e hiahia ana ki te whakatikatika me te whakamātautau taumira. He whānui ōna tono: mai i te mahere i ngā pereti whakaheke me ngā pūnaha magma puia ki te tūhuratanga pūngao me te aromatawai mōrearea rū whenua. Me ngā whanaketanga o ngā whatunga ru whenua, te rorohiko, me ngā tikanga hurihanga (tae atu ki te hurihanga ngaru katoa), ka kaha ake te tātaitanga ru whenua ki te whakaputa i ngā whakaahua koi ake me te whai kōrero ake mō ngā kaupapa pūtaiao me te whakaiti i ngā aituā.
Ki te hiahia koe, ka taea e au te whakarerekē i tēnei tuhinga hei putanga mātauranga ake (me ngā tohutoro me te rārangi pukapuka), ka taea rānei e au te arotahi ki tētahi o ngā tono (hei tauira, te tātaitanga whakaahua mō ngā puia, mō te pūngao waiariki rānei).
