ʻEnekinia Geophysical i ka Hoʻēmi ʻana i nā Pōʻino ʻĀina
ʻO ka ʻāina heʻe kekahi o nā pōʻino geological pinepine loa ma nā wahi wela e like me Indonesia. ʻO ke ʻano mauna, ka ua nui, a me nā hana a kānaka e like me ka hoʻomaʻemaʻe ʻāina, ke kūkulu ʻana i nā alanui, a me ka hana ʻeli ʻana e hoʻolilo i nā pali he nui i mea paʻa ʻole. Hiki i nā hopena ke koʻikoʻi: ka hōʻino ʻana i nā pono hana, ka hoʻopilikia ʻana i ke komo ʻana o ka halihali, nā pohō waiwai, a me ka nalowale ʻana o ke ola. No laila, ʻaʻole hiki ke hilinaʻi wale ka hoʻēmi ʻana i ka ʻāina heʻe i ka pane ulia pōpilikia i ka wā o kahi hanana; pono ia i nā hana pale i hoʻokele ʻia e ka ʻikepili a me ka nānā mau ʻana. ʻO kēia kahi e pāʻani ai nā ʻenehana geophysical i kahi kuleana koʻikoʻi—ma ke ʻano he mau mea hana e "ʻike" i nā kūlana o lalo o ka ʻili me ka ʻole o ka ʻeli nui ʻana, no laila e kōkua ana i ka hoʻomaopopo pono ʻana i nā mea hoʻoulu a me nā wahi i maʻalahi i ka ʻāina heʻe.
Ke Kuleana o Geophysics i ka Hoʻomaopopo ʻana i nā ʻĀina Heʻe
Ma keʻano laulā, hana ʻia nā ʻāina heʻe i ka wā e ʻoi aku ai ka ikaika hoʻokele (e.g., ke kaumaha o ka lepo/pōhaku a me ka mana o ka wai) ma mua o ka ikaika kūʻē (ka ikaika o ka ʻokiʻoki mea a me ke kuʻikahi). ʻO kekahi o nā kī i ka hoʻēmi ʻana, ʻo ia ka ʻike ʻana i nā ʻili paheʻe, nā papa nāwaliwali, nā haki, a me nā ʻano kahe wai ma lalo o ka ʻili e hiki ke hoʻonui i ke kaomi pore. Eia nō naʻe, ʻike ʻole ʻia ka nui o kēia mau ʻāpana mai ka ʻili. Hāʻawi nā ʻenehana geophysical i nā ʻano hana ʻole luku no ka palapala ʻana i nā palena kino o ka pōhaku/lepo e like me ke kūʻē uila, ka wikiwiki o ka nalu seismic, ka pane electromagnetic, a me nā ʻano loli o ke koʻikoʻi. A laila ua wehewehe ʻia kēia mau palena i loko o ka ʻike geological-geotechnical: ka pae saturation wai, ke ʻano mea, nā wahi ʻino, nā lua, a me ka hohonu o ka pōhaku moe.
Ma ke ʻano o ka hoʻēmi ʻana, hoʻohana ʻia ka geophysics i ʻekolu mau pae nui: (1) ka noiʻi mua ʻana o ka nāwaliwali o ka pali, (2) ka hoʻolālā a me ka hoʻolālā ʻana o ka hoʻoikaika ʻana o ka pali, a me (3) ka ʻōlelo aʻo mua ma o nā ana hou ʻana a i ʻole nā ʻōnaehana sensor.
ʻAno Geoelectric (Resistivity) no ke kaha palapala ʻāina ʻana i nā ʻili wai a me nā ʻili paheʻe
ʻO ke ʻano hana geoelectric resistivity kekahi o nā ʻano hana kaulana loa no nā haʻawina ʻāina lepo no ka mea he ʻano pipiʻi ʻole ia, hiki ke lawe ʻia nā lako, a he mea koʻikoʻi ia i ka nui o ka wai. He maʻalahi ke kumumanaʻo: hoʻokomo ʻia kahi au uila i loko o ka lepo ma o nā electrodes, a ana ʻia ka ʻokoʻa hiki ke loaʻa ka resistivity maopopo. ʻO nā mea i hoʻopiha ʻia i ka wai he haʻahaʻa ka resistivity ma mua o nā mea maloʻo, ʻoiai ʻoi aku ka resistive o nā pōhaku paʻakikī.
Ma nā pali i hiki ke hoʻoneʻe ʻia i ka ʻāina, hiki i nā hopena o ke kumu hoʻohālike resistivity 2D a i ʻole 3D ke hōʻike:
– Nā wahi i piha i ka wai a i ʻole nā ala kahe (nā ala kahe wai leachate/wai honua) e hoʻonāwaliwali ai i ka pali.
– Nā papa o ka pālolo a i ʻole ka lepo i palaho i lilo pinepine i mau ʻili pahee no ka mea he pahee lākou i ka wā pulu.
– ʻO ka hohonu o ke kahua pōhaku a me ka mānoanoa o ka lepo i hoʻopōʻino ʻia e ka ʻino, ka mea e hoʻoholo ai i ka hiki ke kūpaʻa ʻole.
I ka hana maoli, hana ʻia nā ana me nā hoʻonohonoho electrode kikoʻī e like me Wenner, Schlumberger, a i ʻole Dipole-Dipole. Koho pinepine ʻia ʻo Dipole-Dipole ma muli o kona hoʻonā maikaʻi no ka ʻike ʻana i nā ʻano ʻaoʻao e like me nā haki a me nā mokulele paheʻe, ʻoiai ʻoi aku ka maʻalahi o ka walaʻau. Pono e hoʻopili ʻia nā wehewehe ʻana o ka resistivity me ka geology o ka ʻili, ka ʻeli ʻana, a i ʻole ka ʻikepili hoʻāʻo hale hana e pale aku i nā hewa—no ka laʻana, hiki i ka resistivity haʻahaʻa ke hōʻike i ka lepo paʻa, akā hiki nō hoʻi ke kumu o kekahi mau mea alakaʻi.
ʻO ka Refraction Seismic a me MASW no ke ʻano o ka ikaika o ka mea
Hoʻohana nā ʻano hana ōlaʻi i ka laha ʻana o nā nalu elastic i ka lepo. ʻElua mau ala maʻamau no ka hoʻēmi ʻana i ka ulia kaʻa, ʻo ia ka seismic refraction a me MASW (Multichannel Analysis of Surface Waves).
1. Kuhi ka refraction seismic i ka wikiwiki o ka nalu P (Vp) e palapala i nā papa a me nā palena o nā mea paʻakikī. ʻO nā wikiwiki kiʻekiʻe e hōʻike pinepine ana i nā pōhaku paʻa a ikaika, ʻoiai ʻo nā wikiwiki haʻahaʻa e hōʻike ana i ka lepo palupalu a i ʻole ka pōhaku i palaho. He mea pono kēia ʻike no ka hoʻoholo ʻana i ka hohonu o ka pōhaku moe a me nā wahi mānoanoa i palaho i maʻalahi i ka ʻāina hāʻule.
2. Nānā nui ʻo MASW i nā nalu ʻili e loaʻa ai kahi ʻano wikiwiki o ka nalu shear (Vs). Pili ʻo Vs me ka paʻakikī (shear modulus) a hiki ke hoʻohana ʻia e ʻike i nā papa palupalu e hiki ke hāʻule. Hoʻohana nui ʻia ʻo MASW no ka mea he kūpono ia ma nā wahi me ka hana kanaka kiʻekiʻe a hiki ke hana ʻia me ka ʻole o nā kumu ikehu nui.
ʻO ka pōmaikaʻi o ke ʻano seismic ʻo ia kona hiki ke hoʻopili pololei i nā palena kino i nā waiwai mechanical. He mea nui nō hoʻi nā ʻano Vs no nā loiloi paʻa o ka pali e noʻonoʻo ana i ka pane ikaika, no ka laʻana ma nā wahi i maʻalahi i ka ōlaʻi—kahi e hiki ai i nā ōlaʻi ke hoʻoulu i nā ʻāina heʻe nui.
ʻO ka Radar Penetrating Ground (GPR) no nā haki pāpaʻu
Hoʻohana ʻo GPR i nā nalu electromagnetic alapine kiʻekiʻe e palapala i nā ʻano papau o lalo o ka ʻilikai. He kūpono loa kēia ʻano hana no ka ʻike ʻana:
– Nā haki a me nā wahi haki ma nā pali,
– Nā loli i ka papa kokoke i ka ʻili,
– Nā lua liʻiliʻi a i ʻole nā ala kahe wai pāpaʻu.
Eia nō naʻe, he mau palena ko GPR: emi nui kāna hana i ka lepo palolo a i ʻole ka lepo pulu loa ma muli o ka emi ʻana o ka nalu. No laila, ʻoi aku ka kūpono o GPR no nā mea pōhaku one, ʻiliʻili, a i ʻole nā mea pōhaku alakaʻi ʻole, a no nā noiʻi pāpaʻu (e.g., he mau mika a he ʻumi mika, ma muli o nā kūlana).
Nā ʻAno Electromagnetic a me Induction no ka Palapala ʻĀina wikiwiki
Hiki i nā ʻano hana electromagnetic (EM) e like me EM31/EM34 a i ʻole nā ʻano hana hoʻokomo electromagnetic ʻē aʻe ke hoʻohālikelike koke i ka conductivity lepo a ma luna o kahi ākea. I nā haʻawina ʻāina hoʻoneʻe, he mea pono kēia mau ʻano hana no:
– Ka nānā mua ʻana e nānā i nā wahi pulu loa a i ʻole nā wahi alakaʻi nui loa,
- Ke ʻike nei i ke ala wai o lalo o ka ʻilikai,
– Kōkua i ke koho ʻana i nā wahi ala geoelectric a i ʻole nā wahi wili.
ʻO ka pōmaikaʻi nui o EM kona wikiwiki; hiki i ka mea hoʻohana ke hele ma ke ala a loaʻa ka ʻikepili mau. ʻO ka hemahema, ʻoi aku ka "laulā" o ka wehewehe ʻana ma mua o ka ERT (Electrical Resistivity Tomography) a hiki ke hoʻopilikia ʻia e ka metala a puni nā wahi noho.
ʻO ka Microtremor a me ka loiloi haʻalulu no ka hōʻailona o ka ʻāpana nāwaliwali
Hoʻohana nā ʻenehana Microtremor (e.g., HVSR—Horizontal to Vertical Spectral Ratio) i nā haʻalulu kūlohelohe e palapala i nā ʻano loli o ka honua. ʻOiai ʻoi aku ka ʻike ʻia no nā haʻawina ōlaʻi, hiki i nā microtremors ke kōkua i ka hoʻēmi ʻana i ka ʻāina hū ma ka ʻike ʻana:
– Ka mānoanoa o ka lepo palupalu ma luna o ka pōhaku moe,
- ʻOkoʻa ka impedance i hiki ke pili i nā kahua nāwaliwali,
– Nā wahi e hoʻonui ai i nā haʻalulu i ʻoi aku ka nāwaliwali i ka wā o nā ōlaʻi a i ʻole nā haʻalulu kaʻa.
ʻO ka hoʻohana ʻana i ka microtremor he mea pono ia ke hui pū ʻia me nā ʻano hana ʻē aʻe e like me MASW a i ʻole geoelectric e hoʻoikaika i ka wehewehe ʻana.
Ka Nānā ʻana i ka Geophysical a me ka Manaʻo Hoʻolaha Mua
ʻAʻole e pau ka hoʻēmi ʻana me ka palapala ʻāina. Hoʻoulu ʻia ka nui o nā ʻāina heʻe e nā loli o ke kau, ʻoiai ka piʻi ʻana o ka wai i ka wā ua lōʻihi. No laila, hiki i nā ana geophysical i hana hou ʻia (time-lapse) ke lilo i mea hana nānā ikaika. Eia kekahi laʻana:
– ERT manawa-lapse e nānā i nā loli resistivity ma muli o ke komo ʻana o ka ua, ka piʻi ʻana o ka pae wai honua, a i ʻole ke kūkulu ʻia ʻana o nā ala kahe hou.
– Ka nānā ʻana i ka seismic passive e ʻike i nā loli microcrack a i ʻole nā neʻe liʻiliʻi e hana ana i nā hōʻailona haʻalulu.
- Hoʻohui pū ʻia me nā mea ʻike geotechnical e like me nā inclinometers, piezometers, a me nā ana ua e kūkulu i nā hiʻohiʻona ʻōlelo aʻo mua e pili ana i ka paepae.
Ma kahi ʻōnaehana kūpono, hāʻawi ka geophysics i kahi kiʻi spatial (kahi i loaʻa ai nā wahi nāwaliwali), ʻoiai hāʻawi nā mea ʻike geotechnical i ka ʻikepili manawa (ke kokoke mai nā kūlana koʻikoʻi). Hoʻomaikaʻi ka hui pū ʻana o nā mea ʻelua i ka hilinaʻi o nā ʻōlelo aʻo mua.
Hoʻohui ʻIkepili a me ka Hoʻoholo Hoʻēmi ʻana
ʻOi aku ka maikaʻi o ka ʻikepili geophysical ke hoʻohui ʻia me nā ʻano hana ʻē aʻe: ka palapala ʻāina geological, ka nānā ʻana i ka pali, ka nānā ʻana i ka hoʻohana ʻāina, a me ka ʻikepili ua a me ka hoʻokahe wai. ʻO ka huahana hoʻēmi hope loa e komo pū ana me:
– Palapala ʻāina nāwaliwali o ka heʻe ʻana (wahi pōʻino),
– Nā ʻōlelo aʻoaʻo ʻenekinia (ka hoʻokahe ʻana o ka pali, nā pā paʻa, ke kui ʻana i ka lepo, ka hoʻoulu hou ʻana i nā mea kanu, a i ʻole ka neʻe ʻana),
– Ke nānā ʻana i nā hoʻolālā a me nā ala e hoʻoneʻe ai.
ʻO kekahi o nā pilikia nui loa, ʻo ia ka wehewehe ʻana i hoʻoponopono ʻole ʻia; no laila, ʻo ka hōʻoia kahua e like me ka ʻeli palena ʻia, ka hoʻāʻo ʻana o SPT, nā nānā ʻana i waho, a i ʻole ka laʻana lepo e mau ana ma ke ʻano he "ʻoiaʻiʻo honua."
Pani
He mea nui nā ʻano hana Geophysical i ka hoʻēmi ʻana i ka ʻāina hoʻoili no ka mea hiki iā lākou ke palapala wikiwiki i nā kūlana o lalo o ka ʻilikai, me ka palekana, a me ka pono. Kōkua nā ʻano hana Geoelectric i ka ʻike ʻana i ka saturation wai a me nā ʻili paheʻe, palapala seismic (refraction a me MASW) i ka paʻakikī a me nā palena o ka pōhaku moe, kōkua nā ʻano hana GPR a me EM me ka ʻike pāpaʻu a me nā ana wikiwiki, ʻoiai ʻo ka nānā ʻana i ka manawa-lapse e wehe i nā manawa kūpono no ka ʻōlelo aʻo mua e pili ana i nā loli i nā kūlana o lalo o ka ʻilikai. Me ka hoʻohui maikaʻi ʻana ma waena o ka geophysics, geology, geotechnics, a me ka hoʻolālā spatial, hiki ke hoʻemi nui ʻia ka pilikia o ka ʻāina hoʻoili—e hoʻomaopopo ana i ka hoʻomohala palekana no nā kaiāulu ma nā wahi pali.
Inā makemake ʻoe, hiki iaʻu ke hoʻololi i kēia ʻatikala i ʻoi aku ka naʻauao (me nā ʻōlelo kuhikuhi a me kahi papa inoa puke), a i ʻole i ʻoi aku ka kaulana no ka hoʻonaʻauao lehulehu, a me ka hoʻohui ʻana i nā hihia haʻawina mai nā wahi kikoʻī ma Indonesia.
