Ka Pilina ma waena o nā Lua Pele a me nā Plate Tectonics
ʻO nā lua pele kekahi o nā hanana kūlohelohe kupaianaha loa ma ka Honua. Hiki i kā lākou mau pele ke hana i nā ʻāina hou, hoʻomāhuahua i ka lepo, a hiki ke hoʻoulu i nā pōʻino weliweli. Akā, ʻaʻole e ʻike wale ʻia nā lua pele. Inā mākou e palapala i nā wahi o nā lua pele hana o ka honua, e puka mai ana kahi ʻano maopopo: he nui o lākou e moe ana ma nā palena o nā papa tectonic . ʻAʻole kēia pilina he mea ulia pōpilikia, akā he hopena pololei ia o ke ʻano o ka hoʻokuʻu ʻana o ka Honua i kona wela kūloko ma o ka neʻe ʻana o nā papa a me ka hoʻokumu ʻana o ka magma.
Ka hoʻomaopopo ʻana i nā papa tectonic a me ke ʻano o ka Honua
Ua haku ʻia ka Honua me kekahi mau papa. ʻO ka mea waho loa ka ʻili lahilahi, ma lalo iho o ia ka mantle, a laila ka ʻiwi waho a me ka ʻiwi o loko. ʻO ka ʻili a me ka ʻaoʻao luna o ka mantle e hana i ka lithosphere paʻa. ʻAʻole paʻa kēia lithosphere, akā ua haki ʻia i loko o nā "papa" nunui i kapa ʻia he mau papa tectonic. Neʻe mālie kēia mau papa ma luna o kahi papa plastic (ka asthenosphere) ma ka wikiwiki o kekahi mau kenimika i kēlā me kēia makahiki.
Hana ʻia ka neʻe ʻana o ka papa honua no ka mea ʻo ka wela mai loko mai o ka Honua e hoʻoulu ai i nā au convection i loko o ka mantle. Piʻi aʻe ka mea wela, hoʻomaʻalili ma luna, a laila piholo hou i lalo. "Paʻi" a "huki" kēia mau au i nā papa honua, e hana ana i nā pilina ma nā palena o ka papa honua: neʻe lākou i kahi kaʻawale (diverge), neʻe kokoke (converge), a paheʻe paha kekahi i kekahi (transform). Hōʻike kēia pilina i ke kumu i hoʻopaʻa ʻia ai nā ʻōlaʻi he nui a me nā lua pele ma kekahi mau wahi.
Pehea e hoʻokumu ʻia ai nā lua pele?
Hoʻokumu ʻia nā lua pele i ka wā e piʻi aʻe ai ka magma—he pōhaku wela i hoʻoheheʻe ʻia mai lalo o ka ʻili—a puka aku ma o nā māwae o ka ʻili. Hiki i ka magma ke hoʻokumu ʻia ma o ʻekolu mau ʻano hana nui:
1. Ka heheʻe ʻana ma muli o ke kaomi i hoʻemi ʻia (decompression melting): hana ʻia ke piʻi aʻe ka mea mantle a kokoke i ka ʻili i hāʻule ai ke kaomi a heheʻe kekahi o ia mea.
2. Ka heheʻe ʻana ma muli o ka hoʻohui ʻana o ka wai/volatiles (flux melting): hana ʻia ke komo ka wai a me nā mea volatile ʻē aʻe i loko o ka mantle, e hoʻohaʻahaʻa ana i ke kiko heheʻe o nā pōhaku i maʻalahi ai ka heheʻe ʻana.
3. Ka heheʻe ʻana ma muli o ka piʻi ʻana o ka mahana (hoʻoili wela): hana ʻia ke hoʻomehana ka magma wela i nā pōhaku a puni a hiki i ka heheʻe ʻana o kekahi o lākou.
Pili loa kēia mau ʻano hana ʻekolu i ke ʻano o ka palena papa tectonic e hana nei.
Nā lua pele ma nā palena ʻokoʻa: ke neʻe kaʻawale nā papa
ʻO ka palena divergent kahi ʻāpana kahi e neʻe ai nā papa ʻelua i kaʻawale. ʻO ka laʻana kaulana loa he kualono waena o ke kai, e like me ka Mid-Atlantic Ridge. Ke kaʻawale nā papa, piʻi aʻe ka mantle e hoʻopiha i ka hakahaka. I kona piʻi ʻana, emi iho ke kaomi, e alakaʻi ana i ka heheʻe hapa (decompression melting). ʻO ka magma hopena he basaltic maʻamau, wai iki, a hana i ka ʻili moana hou.
ʻOi aku ka maʻalahi o ke kahe ʻana o ka pele basaltic palupalu a kakaʻikahi ka pahū ʻana me ka ikaika, ʻoiai he mea weliweli ia, ʻoiai inā kokoke i nā wahi noho (no ka laʻana, ma Iceland, kahi e kau ana ma luna o kahi kualono waena o ke kai a he wahi wela).
Ma waho aʻe o nā moana, hiki ke ʻike ʻia nā palena ʻokoʻa ma ka ʻāina ma ke ʻano o nā māwae, no ka laʻana, ʻo ka East African Rift System. Inā hoʻomau ka ulu ʻana o ka māwae, hiki i ka ʻāina ke māhelehele, e hana ana i moana hou ma luna o nā manawa honua.
Nā lua pele ma nā palena hui: subduction ma ke ʻano he hale hana magma
ʻO ka palena hui kahi e neʻe ai nā papa ʻelua kekahi i kekahi. Inā ʻoi aku ka mānoanoa a me ke anuanu o kekahi papa, e emi ana ia ma lalo o kekahi. ʻO kēia mau wahi emi kahi e loaʻa ai nā lua pele ikaika a weliweli loa o ka honua.
I ka wā e komo ai nā papa moana i loko o ka mantle, lawe lākou i nā minelala a me nā sediments i loaʻa ka wai. Ma kekahi mau hohonu, hoʻokuʻu ʻia ka wai a me nā mea lele i loko o ka mantle ma luna. Hoʻohaʻahaʻa ka wai i ke kiko heheʻe o nā pōhaku mantle, e alakaʻi ana i ka heheʻe ʻana o ke kahe. ʻO ka magma hopena e ʻoi aku ka mānoanoa (andesitic a i rhyolitic) a ʻoi aku ka nui o ke kinoea, e alakaʻi ana i nā pahū ʻana. ʻO kēia ke kumu e pahū pinepine ai nā lua pele he nui ma ke apo ahi o ka Pākīpika me ka ikaika.
ʻO Indonesia kahi laʻana koʻikoʻi o kahi ʻāina i hoʻohālikelike ʻia e kēia kaʻina hana. ʻO ka Indo-Australiaan Plate e hoʻoheheʻe ʻia ana ma lalo o ka Eurasian Plate e hana i ke arc lua pele o Sumatra, Java, Bali, a me Nusa Tenggara. Ma ka hikina, lilo nā pilina o ka papa i mea paʻakikī, e pili ana i ka Pacific Plate a me nā microplates like ʻole, e hopena ana i ka hana seismic a me ka hana lua pele kiʻekiʻe.
Ma waho aʻe o ke kahe ʻana o ka moana-ʻāina, aia kekahi kahe ʻana o ka moana-moana e hana ana i nā piʻo mokupuni e like me nā mea ma Iapana a me Pilipine. I kēia manawa, ʻo nā kuʻi ʻana o ka ʻāina-ʻāina (no ka laʻana, ʻo India a me Eurasia e hana ana i ka Himalayas) e hoʻopuka nui ana i nā mauna a me nā ōlaʻi, akā he kakaikahi nā lua pele, no ka mea, ʻaʻohe papa moana e kahe maʻalahi ana e lawe ana i ka wai e hoʻoulu ai i ka heheʻe.
Ka palena hoʻololi: nui nā ōlaʻi, kakaikahi nā lua pele
ʻO nā palena hoʻololi nā wahi kahi e paheʻe ai nā papa ʻelua kekahi i kekahi. ʻO kahi laʻana i kūkākūkā pinepine ʻia ʻo ia ka San Andreas Fault ma Kaleponi. Ma kēia mau palena, hoʻoulu ka friction a me ka faulting i nā ōlaʻi, akā ma ke ʻano laulā ʻaʻole hana i nā kūlana kūpono no ka hoʻokumu ʻana o ka magma, no laila he mea kakaikahi nā lua pele. Eia nō naʻe, ma kekahi mau wahi, hiki ke pili nā faults hoʻololi me ka hana lua pele inā kokoke lākou i nā palena papa ʻē aʻe a i ʻole e hana i nā māwae e kōkua i ka magma upwelling.
Wela wela: kahi lua pele ʻaʻole i hahai mau i ka palena o ka papa
ʻOiai aia nā lua pele he nui ma nā palena o nā papa, aia kekahi mau ʻokoʻa koʻikoʻi: nā wahi wela. ʻO nā wahi wela nā wahi kahi e piʻi ai nā mea wela mai ka mantle ma ke ʻano he plume a hoʻoheheʻe i ka lithosphere ma luna. I ka neʻe ʻana o nā papa ma luna o nā wahi wela paʻa, hana ʻia kahi kaulahao lōʻihi o nā lua pele e like me ke "ala".
ʻO kahi laʻana maʻamau nā mokupuni ʻo Hawaiʻi. Aia nā lua pele ola ma luna o ka piko wela, ʻoiai ʻoi aku ka mamao o nā mokupuni kahiko ma muli o ka lana ʻana ma ka Papa Pākīpika. Hiki ke loaʻa nā wahi wela ma lalo o nā papa ʻāina, e like me Yellowstone (ʻAmelika Hui Pū ʻIa), nona ka hiki ke hana i nā pele nui ʻoiai ʻaʻole ia ma ka palena o ka papa.
Kōkua nā wahi wela i nā kānaka ʻepekema e hoʻomaopopo i ke kuhikuhi a me ka wikiwiki o ka neʻe ʻana o nā papa honua. Hiki ke hoʻohana ʻia nā kaha makahiki o nā lua pele ma ke kaulahao o nā wahi wela ma ke ʻano he "moʻolelo" o ka neʻe ʻana o nā papa honua ma luna o nā miliona o nā makahiki.
No ke aha he mea nui ka hoʻomaopopo ʻana i kēia pilina?
ʻAʻole wale ka pilina ma waena o nā lua pele a me nā tectonics plate he kumuhana hoʻonaʻauao, akā he hopena pololei ia no ka palekana a me ka hoʻolālā ʻāina . Ma ka hoʻomaopopo ʻana i nā ʻano palena o ka papa, hiki i nā loea ke wānana:
– Ke ʻano o ka pahū ʻana e hiki mai ana (effusive a explosive paha),
– Nā pōʻino nui (nā kahe pele, nā ao wela, nā lahar, ka ua lehu),
– Nā ʻano hoʻolaha o ka lua pele a me ka hiki ke puka mai nā kikowaena pele hou,
– Ka pilina me nā ōlaʻi ma muli o ka neʻe ʻana o nā papa honua.
Ma nā wahi e like me Indonesia, he mea nui kēia ʻike no ka hoʻēmi ʻana i nā pōʻino . ʻO ke kaha palapala ʻana i nā wahi subduction, ka nānā ʻana i ka hana seismic, ka hoʻololi ʻana o ka honua, a me nā kinoea pele he ʻāpana ia o ka ʻōnaehana hoʻomaopopo mua. Loaʻa pū ka pōmaikaʻi o nā kaiāulu mai ka hoʻonaʻauao pōʻino i hiki iā lākou ke pane kūpono i ka piʻi ʻana o ka hana pele.
Ka hopena
Ua pili loa nā lua pele a me nā tectonics o ka papa no ka mea e hoʻokumu ka neʻe ʻana o ka papa i nā kūlana e paipai ai i ka hoʻokumu ʻana o ka magma. Ma nā palena divergent, hana ʻia ka magma ma muli o ke kaomi i hoʻemi ʻia i ka piʻi ʻana o ka mantle. Ma nā palena convergent, ʻoiai nā subduction zones, hana ʻia ka magma no ka mea e hoʻohaʻahaʻa ka wai a me nā mea volatile i ka pae heheʻe o nā pōhaku, e hopena ana i nā lua pele pahū e hana pinepine ana i nā arcs volcanic. Ma ka ʻaoʻao ʻē aʻe, hoʻoulu nā palena Transform i nā ōlaʻi ma mua o nā lua pele. Eia kekahi, hōʻike nā wahi wela e hiki ke hana ʻia ka hana lua pele ma kahi mamao aku o nā palena papa.
ʻO ka hoʻomaopopo ʻana i kēia pilina e kōkua iā mākou e wehewehe i ka "palapala ʻāina pōpilikia" o ka Honua, wehewehe i ke kumu he nui nā lua pele i kekahi mau wahi, a hoʻoikaika i nā hana hoʻēmi pōpilikia. No laila, ʻaʻole wale ka ʻepekema o nā tectonics plate e wehewehe i ka dynamics planetary akā hāʻawi pū i kahi kahua koʻikoʻi no ka pale ʻana i ke ola kanaka ma nā wahi i maʻalahi i ka volcanism.
