Kuyini Radiocarbon Dating?

Radiocarbon ukuphola usewushintshile umbono wethu esidlule 50,000 iminyaka. UProfesa Willard Libby lokuqala kwabonisa ke ngo-1949, i-okuyinto kamuva uMklomelo KaNobel.

ukuphola indlela

I ukuphola essence Radiocarbon ukuqhathanisa ezintathu carbon isotopes ezahlukene. Isotopes yesici esithile ube inani elifanayo proton nucleus kodwa izinombolo ezihlukene neutrons. Lokhu kusho ukuthi enkulu chemical ukufana banayo uquqaba ezahlukene.

Ungqimba isamba IKhompyuthaYami luchazwa ngegama index zezinombolo. Ngenkathi isotopes ukuxegiselwa ¹² C no ¹³ C izinze, olusindayo IKhompyuthaYami ¹⁴ C (Radiocarbon) kuyinto enemisebe. enkabeni yalo enkulu ukuze engazinzile.

Ngokuhamba kwesikhathi ¹⁴ C - base Radiocarbon - ubola ku-nitrogen ¹⁴ N. Iningi-carbon-14 kudalwa emkhathini lapho neutrons okuyinto yilabo abake ngemisebe cosmic ukuxubana athomu ¹⁴ N.

Wabe oxidized ku ¹⁴ CO _2, ingena emkhathini futhi Ihlangana ne ¹² CO ₂ kanye ¹³ CO _2. Carbon dioxide isetshenziswa izitshalo ngesikhathi i-photosynthesis, futhi ukusuka lapho sidlula eziwukudla. Ngakho-ke, iyiphi nezitshalo nezilwane esikuziphathimandla (kuhlanganise nabantu) kuyodingeka isamba alinganayo ¹⁴ C kuqhathaniswa ne ¹² C ngaphansi kwesimo (ratio C ^14: C ^12).

ukulinganiselwa

Lapho nezilwane zifa, kuba ijwabu is ayisekho indawo kanye kwamazinyo enemisebe ¹⁴ C iba sobala. Through iminyaka 55.000 ¹⁴ C ihlukaniswe ukuze engasakwazi ukukala izinsalela.

Kuyini Radiocarbon Dating? kwamazinyo Radioactive ingasetshenziswa njengendlela "iwashi", ngoba akuxhomekile ngokomzimba (isib lokushisa) namakhemikhali (isib okuqukethwe amanzi) izimo. Iminyaka 5730, ihlukaniswe nengxenye ^{ye-C 14,} eziqukethwe isampula.

Ngakho-ke, uma sazi isilinganiso ¹⁴ C: ¹² C ngesikhathi sokufa futhi isilinganiso wamanje, ungakwazi ukubala isidlulile singakanani isikhathi. Ngeshwa, ukukhomba kubo akulula kangako.

Radiocarbon ukuhlaziywa: iphutha

^{Inani 14} C emkhathini, ngakho ezitshalweni nasezilwaneni, kwakungelula ngaso sonke isikhathi njalo. Isibonelo, iyahlukahluka kuye ngokuthi indlela imisebe eminingi cosmic ukufinyelela Earth. It kuxhomeke kulokho okwenzeka elanga futhi amandla kazibuthe iplanethi yethu.

Ngenhlanhla, kungaba lezi iyehla iyenyuka ulinganiswa amasampula sangomhla ngu ezinye izindlela. Ungakwazi ukubala izindandatho ukukhula kwemithi izinguquko Radiocarbon okuqukethwe. "Samandla ijika" kungenziwa zakhiwa lezi idatha.

Okwamanje, umsebenzi uyaqhubeka yokusakazeka kanye ngcono. Ngo-2008, kungenzeka ukuba ikwazi kuphela izinsuku Radiocarbon iminyaka engu-26.000. Namuhla ijika enwetshiwe iminyaka engu-50,000.

Yini engase alinganiswe?

Akubona bonke izinto kungenziwa sangomhla ngale ndlela. Iningi, uma kungewona wonke, of organic compounds uvumele Radiocarbon ukuhlaziywa. Eminye wezinto ezifana aragonite ingxenye amagobolondo ingaphinda idethi, njengoba lisetshenziswe kumiswa amaminerali-carbon-14.

Izinto eziye sangomhla kusukela kwasungulwa indlela zihlanganisa amalahle, izinkuni, amahlumela, imbewu, amathambo, amagobolondo, lesikhumba, Peat, daka, inhlabathi, izinwele, izinto ezenziwe ngobumba, impova, udonga imidwebo, amakhorali, igazi asalile, izicubu, iphepha, isikhumba, resin namanzi.

Uhlaziyo Radiocarbon metal akunakwenzeka uma ayiqukethe i-carbon-14. Ngaphandle kukhona, nabensimbi, ekhiqizwa kusuka amalahle isetshenziswa.

bill double

Ngenxa yalokhu inkinga, izinsuku Radiocarbon ethulwa ngezindlela ezimbili. Izilinganiso uncalibrated zikhishwa eminingana kuze 1950 (BP). ukukhetha ulinganiswe naye wethulwe njengelungu BC. e., futhi ngemva, kanye ngokusebenzisa calBP amayunithi (ulinganiswe kuze kube manje, kuze 1950). Lena "kancono" yobudala langempela isampula, kodwa kufanele ukwazi ukubuyela idatha ubudala futhi ulinganise kubo njengoba izifundo ezintsha njalo kokubuyekeza ijika Samandla.

Zokwandisa nokuthuthukisa ikhwalithi

Ubunzima yesibili izigameko eliphansi kakhulu ¹⁴ C. 0,0000000001 kuphela% carbon esimweni zanamuhla ¹⁴ C, elibangela ukuba yinkimbinkimbi ngendlela engakholeki ngokuba nesilinganiso kuwenze ezikhathalela kakhulu ukusilaphazeka.

Eminyakeni yokuqala ka Radiocarbon ukuhlaziya imikhiqizo kwamazinyo yafuna amasampula omkhulu ngokweqile (isibonelo, kwesigamu kunawo wonke womuntu). laboratories Abaningi manje i-mass spectrometer nge namafutha (AMS), elikwazi ukuzwa futhi ulinganise khona isotopes ahlukahlukene futhi babala inombolo yetinhlavu ngabanye ama-athomu carbon-14.

Le ndlela idinga esingaphansi 1 igremu kwethambo, kodwa amazwe ambalwa ukwazi ukukhokhela okwengeziwe kweyodwa noma ezimbili we-AMS, ukubaluleka eyeqa ayizinkulungwane 500. $. Ngokwesibonelo, e-Australia inamadivayisi enjalo ezimbili kuphela akwazi Radiocarbon ukuhlaziywa, zinjalo sisithole kakhulu emazweni asathuthuka.

Hlanza - isiqinisekiso ukunemba

Ngaphezu kwalokho, amasampula kumele kahle sihlanza carbon ukungcoliswa ingcina nomhlabathi. Lokhu kubalulekile ikakhulukazi izinto ezindala kakhulu. Uma-1% sakhi engu isampula ayizinkulungwane 50. Iminyaka ayovela ukungcola yesimanje, uzathwala kokubili sorokatysyacheletnyaya.

Ngenxa yalesi sizathu, abacwaningi njalo ekuthuthukiseni izindlela ezintsha zokuthola izinsuku ngempumelelo yokuhlanza izinto. Abakwazi nomthelela kwi yalokho, onikeza ukuhlaziywa Radiocarbon. Ukunemba ikhuphuke kakhulu ukuthuthukiswa indlela entsha yokwelashwa nge-carbon isebenze ABOx-SC. Lokhu kwenza ukuba, isibonelo, alibale ukufika wabokuqala e-Australia ezingaphezu kwezingu-10 eziyinkulungwane. Iminyaka.

Radiocarbon ukuhlaziywa: a critique

Indlela efakazela ukuthi kusukela ukuvela Umhlaba wathatha okuningi kuka-10 eziyinkulungwane. Iminyaka okukhulunywa ngabo eBhayibhelini, iye ngokuphindaphindiwe wagxeka indalo yadalwa ngezinsuku. Ngokwesibonelo, bathi Iminyaka engaphezu kwengu-50 eziyinkulungwane., Akufanele kube khona i-carbon-14 amasampula, kodwa samalahle, uwoyela negesi yemvelo, ubudala, okuthathwa njengokumele kube ibe izigidi zeminyaka ubudala, iqukethe amanani esilinganisekayo lokhu IKhompyuthaYami, okufakazela ukuhlaziya Radiocarbon. Iphutha Ukumeda ngesikhathi esifanayo okwengeziwe emisebeni yangemuva, kusukela lapho akunakwenzeka ukuqeda endaweni yokucwaninga kuka. E. Isampula okuyinto ayinazo carbon athomu enemisebe, bonisa usuku th 50. S. Nokho, leli qiniso akusho ebekela dating amasayithi kanye nobufakazi ngisho kancane ukuthi uwoyela, amalahle kanye negesi yemvelo bangaphansi ukuthi ubudala.

Indalo yadalwa ngezinsuku ngikuveze ezinye ukuhlaziywa babhekwa Radiocarbon. Ngokwesibonelo, ukuphola angenasawoti silwanyana kunqunywa ubudala babo njengoba iminyaka engaphezu kuka-2,000, okuyinto, ngokombono wabo, ngodaka le ndlela. Empeleni wathola ukuthi iningi shellfish okulungiselelwe kusuka carbon limestone kanye humus okuqukethwe ¹⁴ C okuyinto liphansi kakhulu, kusukela lezi namaminerali sezigugile futhi abanawo carbon emoyeni. Radiocarbon ukuhlaziywa, ukunemba okuyinto kuleli cala kungenziwa ngemibuzo, e lonke icala. Izinkuni Ngokwesibonelo, akanayo inkinga enjalo, isb. K. Isimila etholwe carbon ngokuqondile emoyeni, equkethe umthamo ogcwele ¹⁴ C.

Enye impikiswano aqondiswe indlela Kuyaphawuleka ukuthi izihlahla bayakwazi ukwakha ngomnyaka owodwa ezingaphezu kweyodwa indandatho. Lokhu kuyiqiniso, kodwa kaningi kwenzeka ukuthi musa yakha izindandatho yonyaka. bristlecone pine, ngesisekelo okuyinto eyenziwa iningi izilinganiso kuyinto izindandatho 5% uma kuqhathaniswa nangonyaka yobudala wakhe uqobo.

Ukusungula idethi

Radiocarbon ukuhlaziywa - indlela hhayi kuphela, kodwa ukutholakala futhi okuthakazelisayo esidlule wethu nezamanje. Indlela avunyelwe Abavubukuli beka okutholakele ngokulandelana kwezenzakalo, ngaphandle kwesidingo olotshiwe noma zemali.

Esikhathini 19 futhi ekuqaleni kwekhulu lama-20, Liyindawo nesineke futhi abavubukuli baqaphe ezihambisana zobumba kanye itshe amathuluzi ezindaweni ezahlukahlukene okudabuka ngokuthola ezifuze bobunjwa amaphethini. Khona-ke, usebenzisa umqondo wokuthi izitayela into ziye zashintsha futhi babe uyinkimbinkimbi kakhulu ngokuhamba kwesikhathi, bakwazi ukubeka oda zabo.

Ngakho, umkhatsi ethuneni elikhulu (eyaziwa ngokuthi Tolosa) e Greece kubhekwe kokumethemba izakhiwo ezinjalo esiqhingini Scottish Maeshowe. Lokhu kusekela umbono wokuthi impucuko zasendulo IGrisi NeRoma kwakungasehlane laseBeti maphakathi emisha.

Nokho, ngenxa uvivinyo Radiocarbon wembula ukuthi amathuna Scottish kwakukhona izinkulungwane abaneminyaka engaphezu kuka-esiGrekini. Northern namaqaba bakwazi ukuklama izakhiwo eziyinkimbinkimbi, afana zakudala.

Okunye iphrojekthi Owaziwa kakhulu ukunikezwa kwemisebenzi kulowo Indwangu eTurin kuya enkathini ephakathi, lo ukuqomisana YasoLwandle Olufile kwesikhathi sikaKristu, futhi abambalwa impikiswano periodization imidwebo Chauvet emhumeni yobudala 38.000 calBP (mayelana 32.000 BP), ezinkulungwaneni zeminyaka ngaphambi kwalokho kunokulindelekile.

Radiocarbon ukuhlaziywa yayisetshenziswa nasekuchazeni ekunqumeni isikhathi yokuqothulwa mammoth kanye nomthelela empikiswaneni abantu yesimanje kanye AmaNeanderthal wahlangana noma cha.

I IKhompyuthaYami ¹⁴ C alisetshenziswa kuphela anqume yobudala. Radiocarbon Dating ndlela ivumela omunye ukufunda ocean kwegazi sihlaziye izinga esesithuthuke ngalo ukunyakaza izidakamizwa wonke umzimba, kodwa lena nesihloko esinye isihloko.