palms

60:3.885,000,000 years ago the Bering Strait closed, shut­ting off the cool­ing wa­ters of the north­ern seas. Thereto­fore the ma­rine life of the At­lantic-Gulf wa­ters and that of the Pa­cific Ocean had dif­fered greatly, ow­ing to the tem­per­a­ture vari­a­tions of these two bod­ies of wa­ter, which now be­came uni­form.

60:3.9The de­posits of chalk and green­sand marl give name to this pe­riod. The sed­i­men­ta­tions of these times are var­ie­gated, con­sist­ing of chalk, shale, sand­stone, and small amounts of lime­stone, to­gether with in­fe­rior coal or lig­nite, and in many re­gions they con­tain oil. These lay­ers vary in thick­ness from 200 feet in some places to 10,000 feet in west­ern North Amer­ica and nu­mer­ous Eu­ro­pean lo­cal­i­ties. Along the east­ern bor­ders of the Rocky Moun­tains these de­posits may be ob­served in the up­tilted foothills.

60:3.10All over the world these strata are per­me­ated with chalk, and these lay­ers of porous semirock pick up wa­ter at up­turned out­crops and con­vey it down­ward to fur­nish the wa­ter sup­ply of much of the earth’s pres­ent arid re­gions.

60:3.1180,000,000 years ago great dis­tur­bances oc­curred in the earth’s crust. The west­ern ad­vance of the con­ti­nen­tal drift was com­ing to a stand­still, and the enor­mous en­ergy of the slug­gish mo­men­tum of the hin­ter con­ti­nen­tal mass up­crum­pled the Pa­cific shore line of both North and South Amer­ica and ini­ti­ated pro­found reper­cus­sional changes along the Pa­cific shores of Asia. This cir­cum­pa­cific land el­e­va­tion, which cul­mi­nated in pres­ent-day moun­tain ranges, is more than twenty-five thou­sand miles long. And the up­heavals at­ten­dant upon its birth were the great­est sur­face dis­tor­tions to take place since life ap­peared on Uran­tia. The lava flows, both above and be­low ground, were ex­ten­sive and wide­spread.

60:3.1275,000,000 years ago marks the end of the con­ti­nen­tal drift. From Alaska to Cape Horn the long Pa­cific coast moun­tain ranges were com­pleted, but there were as yet few peaks.

60:3.13The back­thrust of the halted con­ti­nen­tal drift con­tin­ued the el­e­va­tion of the west­ern plains of North Amer­ica, while in the east the worn-down Ap­palachian Moun­tains of the At­lantic coast re­gion were pro­jected straight up, with lit­tle or no tilt­ing.

60:3.1470,000,000 years ago the crustal dis­tor­tions con­nected with the max­i­mum el­e­va­tion of the Rocky Moun­tain re­gion took place. A large seg­ment of rock was over­thrust fif­teen miles at the sur­face in British Columbia; here the Cam­brian rocks are obliquely thrust out over the Cre­ta­ceous lay­ers. On the east­ern slope of the Rocky Moun­tains, near the Cana­dian bor­der, there was an­other spec­tac­u­lar over­thrust; here may be found the pre­life stone lay­ers shoved out over the then re­cent Cre­ta­ceous de­posits.

60:3.15This was an age of vol­canic ac­tiv­ity all over the world, giv­ing rise to nu­mer­ous small iso­lated vol­canic cones. Sub­ma­rine vol­ca­noes broke out in the sub­merged Hi­malayan re­gion. Much of the rest of Asia, in­clud­ing Siberia, was also still un­der wa­ter.

60:3.1665,000,000 years ago there oc­curred one of the great­est lava flows of all time. The de­po­si­tion lay­ers of these and pre­ced­ing lava flows are to be found all over the Amer­i­cas, North and South Africa, Aus­tralia, and parts of Eu­rope.

60:3.17The land an­i­mals were lit­tle changed, but be­cause of greater con­ti­nen­tal emer­gence, es­pe­cially in North Amer­ica, they rapidly mul­ti­plied. North Amer­ica was the great field of the land-an­i­mal evo­lu­tion of these times, most of Eu­rope be­ing un­der wa­ter.

60:3.18The cli­mate was still warm and uni­form. The arc­tic re­gions were en­joy­ing weather much like that of the pres­ent cli­mate in cen­tral and south­ern North Amer­ica.