
trutiyak

trutiyak () hii 66 dashalaksh teey 26 laakh varshanpurvichya bhoogarbhiy kalavadhisathi eka aprachalit sandnya aahe. 
senozoic yugachya suruvatila, cretaceous-paleogen namshesh honyachya ghatanet naun-avian dynasorechya mrutyusah yaa kalavadhichi suruvat jhaali aanee playocene yugachya shevati chaturthansh himanadyaparyant vistarla. sadhyachya bhoogarbhiy vel pranalimadhye trutiyakane vyapalelya kalavadhiche nemke samatulya nahee, parantu heey moolatah villin jhalele paleogen aanee neogene kalavadhi aahet, jyanna anaupacharikpane anukrame prarambhik trutiyak aanee usheera trutiyak mhanatat.
yaa shabdacha aitihasik vapar.
18 vya shatkachya madhyat jiovanni ardino yanni truteey haah shabd pahilyanda vaparla. tyanni uttar italitil bhoogarbhshastrachya nirikshananchya aadhare bhoogarbhiy veleche adim (kinwa prathamik), duyyam aanee trutiyak kalkhandanmadhye vargikaran kele. nantar chauthya kalavadhisathi, chaturthansh, lagoo karnyat aala.
bhuvidnyan abhyasachya suruvatichya vikasat, shastrashastriy bhuvaidnyanikanni haah kaal baybalsambandhichya varnanashi sambandhit asalyache manale hote, truteey starache khadak mothya purashi sambandhit asalyache manale jaat hote.
1833 madhye charles layalane, tyane italimadhye gola kelelya jivashma molsk aanee 'aay. dii. 1' madhye 'cicilly' varr aadharit, tyachya swatachya, adhik tapshilvar vargikaran pranalimadhye eka trutiyak kalavadhi samavisht keela. tyaa staranmadhye aadhalanaya aadhunik prajatinshi samya asalelya jivashma molaskachya takkevarinusar tyane trutiyak kalavadhiche chaar yuganmadhye vibhajan kele. tyane greek nave vaparalih eocene, myosene, june pliocene aanee naveen pliocene.
jaree heey vibhag moolatah jyaa pradeshala heey padnam lagoo kele gele hote (alpsche kahee bhag aanee italichya maidani bhag) tyasathi purese vatat asale, taree nantar jevha teech pranali europechya itar bhaganmadhye aanee americet vistarli gelee, tevha tee lagoo houu shakali nahee. tyamule, molaskacha vapar vyakhyepasun sodoon denyat aala aanee yuganche naav badaloon tyanchi punarnirdharan karnyat aalee.
jyaa kalat 'trutiyak' haah shabd aupcharik vaparat hota, tyaa kalat bahutek vela too 65 teey 18 laakh varshanpurvichya kalavadhicha sandarbh dett asey. cretatiuschi shevatchi tarikh aanee chaturthanshachi prarambhichi tarikh nantar see yethe punarnirdharit kelee gelee. anukrame 66 aanee 26 laakh varshanpurvi.
aadhunik samatulya.
jaree tyala aata starikaranababatchya aantarrashtriy aayogane aupcharik ekak mhanoon manyata dileli nasali, taree trutiyak kalavadhi haah mesozoic yug aanee chaturthansh kalavadhichya darmyan aahe.
trutiyak kalavadhiche paleocene (66-56 dashalaksh varshe bii. pii.), eocene (56-33.9 dashalaksh varshe bii. pii.), oligosine (33-23.9 dashalaksh varshe bii. pii.), myosene (23-5.3 dashalaksh varshe bii. pii.) aanee pliocene (5.3-2.6 dashalaksh varshe bii. pii.) asey upavibhajit kele aahe, jeey plistocenechya pahilya tappyaparyant vistarle aahe, gelasian tappa.