Soo koob maqaalka:  Khubarada cilmiga qadiimiga ah waxay soo ogaadeen qalab dhagax ah oo ku yaalla Oregon kaasoo muujinaya in dadku ay qabsadeen galbeedka Maraykanka waqti ka hor intii la moodayay. Qalabka dhagaxa ah ee loo yaqaano 'agate' waxaa laga soo saaray lakab qaro weyn oo dambas fulkaane ah taasoo ka dhalatay qaraxii Mount St. Helens 15,800 sano ka hor. Saynisyahannadu waxay aaminsan yihiin in mindigii asalka ahaa, oo laga helay 12ft (3.6 mitir) dhulka hoostiisa, loo isticmaali jiray in lagu jaro maqaarka xayawaanka, hilibka, iyo qoryaha lagu xardho dadka ka hor Clovis. Khubarada cilmiga qadiimiga ah waxay soo ogaadeen qalab dhagax ah oo ku yaalla Oregon kaasoo muujinaya in dadku ay qabsadeen galbeedka Maraykanka waqti ka hor intii la moodayay. Qalabkan agate-ka ah waxaa laga soo saaray lakab qaro weyn oo dambas fulkaane ah oo ka soo baxay markii uu qarxay Mount St Helens 15,800 sano ka hor. Waxyaabaha la helay, ee Rimrock Draw Rockshelter, waxaa maanta ku dhawaaqay Xafiiska Maareynta Dhulka ee Maraykanka, kaas oo maamula dhulka laga helay goobta. Arkeolog Scott Thomas ayaa sheegay in haddii da'da aagga la xaqiijiyo, ay noqon doonto raadkii ugu da'da weynaa ee Clovis ka hor laga helo galbeedka Rocky Mountains. Waxay kaloo ka weyntahay midka ka horeeyay ee la yiraahdo dhaqanka Clovis, kaasoo la aaminsanaa in uu ahaa dadkii ugu horeeyay ee ka haajira Asia kuna soo gala Waqooyiga Ameerika. Waxyaalihii ugu da'da weynaa ee laga helay Clovis, oo lagu yaqaanay dhagaxyo xarrago leh oo qurux badan, waxay soo jireen ilaa 13,000 oo sano ka hor. Professor Patrick O'Grady oo ka tirsan jaamacadda Oregon ayaa ku tilmaamay daahfurka'mid cajiib ah' Waxyaabaha la helay, ee Rimrock Draw Rockshelter, waxaa maanta ku dhawaaqay Xafiiska Maareynta Dhulka ee Maraykanka, kaas oo maamula dhulka laga helay goobta. Khabiirka cilmiga qadiimiga ah ee Scott Thomas ayaa sheegay in haddii da'da aagga ay u istaagto baaritaanka, ay noqon doonto tan ugu da'da weyn galbeedka Rocky Mountains. Laakiin wuxuu intaa ku daray in ay doonayaan in ay sii wadaan qodista xagaagan si ay u arkaan in dambaska volcanic uu daboolayo aagga oo dhan. Donald Grayson, oo ah borofisar cilmiga qadiimiga ah ka dhiga jaamacada Washington, ayaa sheegay in cilmiga saynisku uu shaki ku jiro. Laba goobood oo Clovis ka horeeyey si fiican ayaa loo diiwaangeliyey waxayna si guud u aqbaleen saynisyahannadu. Mid ka mid ah waa godka Paisley, oo ku yaalla qiyaastii 60 miles koonfur galbeed ee goobta Rimrock. Midka kale waa Monte Verde ee Chile. Labaduba waa...
Qalabka dhagaxa ah waxaa laga helay hooska ash volcanic ah. Waxaa loo isticmaali jiray in lagu gooyo maqaarka, hilibka, iyo in lagu xardho qoryo. Waxaa laga helay Rimrock Draw Rockshelter oo ku taalla koonfurta bari ee Oregon. Hadii taariikhda Rimrock ay sax tahay, waxay dadka gelinaysaa goobta qiyaastii 1,500 oo sano ka hor inta aan la rumaysan, dhamaadkii xilligii Pleistocene.