leej twg nrhiav tau magnetic reversals

Sib nqus reversals xa mus rau cov txheej txheem uas lub ntiaj teb magnetic teb hloov kev coj, ua rau sab qaum teb thiab sab qab teb magnetic ncej hloov chaw.

Qhov kev tshawb pom ntawm magnetic reversals yog muab rau ob tug kws tshawb fawb, Bernard Brunhes thiab Motonori Matuyama. Brunhes, ib tug Fabkis txoj geophysicist, nrhiav tau pov thawj ntawm magnetic reversal nyob rau hauv volcanic pob zeb nyob rau hauv 1906. Nws pom tias cov pob zeb muaj alternating bands ntawm ib txwm thiab thim rov qab magnetic polarity. Qhov no qhia tau hais tias lub ntiaj teb magnetic teb tau dhau los ua ntau qhov kev hloov pauv thoob plaws hauv nws keeb kwm.

Motonori Matuyama, ib tug Japanese geophysicist, kuj nrhiav tau pov thawj ntawm magnetic reversal nyob rau hauv lig 1920s. Nws pom tias qee cov pob zeb thaum ub muaj cov khoom siv hlau nplaum uas tau taw qhia rau sab qab teb tsis yog sab qaum teb. Qhov kev tshawb pom no tau ua rau nws qhia tias lub ntiaj teb cov hlau nplaum tau dhau los ua qhov rov qab ua tiav txog 700,000 xyoo dhau los.

Kev tshawb pom ntawm magnetic reversals yog qhov tseem ceeb vim nws muab pov thawj rau phaj tectonics thiab kev txav ntawm cov teb chaws. Lub ntiaj teb magnetic teb ua raws li daim ntaub thaiv npog uas tiv thaiv peb ntawm hnub ci cua thiab teeb meem cosmic rays. Kev nkag siab txog kev thim rov qab sib nqus yog qhov tseem ceeb rau kev kwv yees tus cwj pwm ntawm lub ntiaj teb cov hlau nplaum thiab tiv thaiv peb tus kheej los ntawm kev puas tsuaj.