Dab tsi yog cov ntxhia uas feem ntau siv rau kev sib tham?
Dab tsi yog cov ntxhia uas feem ntau siv rau kev sib tham?

Video: Dab tsi yog cov ntxhia uas feem ntau siv rau kev sib tham?

Video: Dab tsi yog cov ntxhia uas feem ntau siv rau kev sib tham?
Video: Nkauj mos ab ib txhia tub sab 7/25/2018 2024, Hlis ntuj nqeg
Anonim

Potassium-Argon (K-Ar) sib tham yog cov feem ntau dav siv cov txheej txheem ntawm radiometric sib tham . Potassium yog ib feem ntawm ntau yam cov minerals thiab tuaj yeem yog siv los txiav txim lub hnub nyoog ntawm igneous thiab metamorphic pob zeb.

Raws li txoj cai, cov pob zeb twg uas feem ntau siv rau kev sib tham zircon?

Ob tug decay chains siv ntawm zircon sib tham yog cov uranium series thiab actinium series. Lub neej ib nrab ntawm cov uranium series yog 4.47 billion xyoo, thiab ib nrab lub neej ntawm actinium series yog 710 lab xyoo. Thaum ib tug grain ntawm ntxhia daim ntawv, lub moos pib ntawm xoom.

Kuj Paub, leej twg ntawm cov isotope hauv qab no feem ntau siv rau cov khoom sib tham? Ib tug ntawm Feem ntau cov isotopes siv nyob rau hauv xov tooj cua sib tham yog uranium-235 lossis U-235.

Ntawm no, dab tsi yog 3 txoj hauv kev sib tw pob zeb?

Ua ke nrog cov hauv paus ntsiab lus stratigraphic, radiometric sib tham Cov txheej txheem yog siv nyob rau hauv geochronology los tsim kom tau lub sij hawm geology. Ntawm cov txheej txheem paub zoo tshaj plaws yog radiocarbon dating, poov tshuaj -argon dating thiab uranium-lead dating.

Dab tsi yog siv rau hnub tim pob zeb thiab cov zaub mov?

Vim tias lawv qhov tshwj xeeb tsis zoo, cov ntsiab lus sib txawv yog siv rau kev sib tham hnub nyoog sib txawv. Piv txwv li, kev lwj ntawm poov tshuaj - 40 rau argon -40 yog siv rau hnub tim pob zeb uas muaj hnub nyoog tshaj 20,000 xyoo, thiab kev lwj ntawm uranium-238 rau coj -206 yog siv rau pob zeb qub tshaj 1 lab xyoo.

Pom zoo: