chalk

60:3.1The great Cre­ta­ceous pe­riod de­rives its name from the pre­dom­i­nance of the pro­lific chalk-mak­ing foraminifers in the seas. This pe­riod brings Uran­tia to near the end of the long rep­til­ian dom­i­nance and wit­nesses the ap­pear­ance of flow­er­ing plants and bird life on land. These are also the times of the ter­mi­na­tion of the west­ward and south­ward drift of the con­ti­nents, ac­com­pa­nied by tremen­dous crustal de­for­ma­tions and con­comi­tant wide­spread lava flows and great vol­canic ac­tiv­i­ties.

60:3.2Near the close of the pre­ced­ing ge­o­logic pe­riod much of the con­ti­nen­tal land was up above wa­ter, al­though as yet there were no moun­tain peaks. But as the con­ti­nen­tal land drift con­tin­ued, it met with the first great ob­struc­tion on the deep floor of the Pa­cific. This con­tention of ge­o­logic forces gave im­pe­tus to the for­ma­tion of the whole vast north and south moun­tain range ex­tend­ing from Alaska down through Mex­ico to Cape Horn.

60:3.3This pe­riod thus be­comes the mod­ern moun­tain-build­ing stage of ge­o­logic his­tory. Prior to this time there were few moun­tain peaks, merely el­e­vated land ridges of great width. Now the Pa­cific coast range was be­gin­ning to el­e­vate, but it was lo­cated seven hun­dred miles west of the pres­ent shore line. The Sier­ras were be­gin­ning to form, their gold-bear­ing quartz strata be­ing the prod­uct of lava flows of this epoch. In the east­ern part of North Amer­ica, At­lantic sea pres­sure was also work­ing to cause land el­e­va­tion.

60:3.4100,000,000 years ago the North Amer­i­can con­ti­nent and a part of Eu­rope were well above wa­ter. The warp­ing of the Amer­i­can con­ti­nents con­tin­ued, re­sult­ing in the meta­mor­phos­ing of the South Amer­i­can An­des and in the grad­ual el­e­va­tion of the west­ern plains of North Amer­ica. Most of Mex­ico sank be­neath the sea, and the south­ern At­lantic en­croached on the east­ern coast of South Amer­ica, even­tu­ally reach­ing the pres­ent shore line. The At­lantic and In­dian Oceans were then about as they are to­day.

60:3.595,000,000 years ago the Amer­i­can and Eu­ro­pean land masses again be­gan to sink. The south­ern seas com­menced the in­va­sion of North Amer­ica and grad­u­ally ex­tended north­ward to con­nect with the Arc­tic Ocean, con­sti­tut­ing the sec­ond great­est sub­mer­gence of the con­ti­nent. When this sea fi­nally with­drew, it left the con­ti­nent about as it now is. Be­fore this great sub­mer­gence be­gan, the east­ern Ap­palachian high­lands had been al­most com­pletely worn down to the wa­ter’s level. The many col­ored lay­ers of pure clay now used for the man­u­fac­ture of earth­en­ware were laid down over the At­lantic coast re­gions dur­ing this age, their av­er­age thick­ness be­ing about 2,000 feet.

60:3.6Great vol­canic ac­tions oc­curred south of the Alps and along the line of the pres­ent Cal­i­for­nia coast-range moun­tains. The great­est crustal de­for­ma­tions in mil­lions upon mil­lions of years took place in Mex­ico. Great changes also oc­curred in Eu­rope, Rus­sia, Japan, and south­ern South Amer­ica. The cli­mate be­came in­creas­ingly di­ver­si­fied.

60:3.790,000,000 years ago the an­giosperms emerged from these early Cre­ta­ceous seas and soon over­ran the con­ti­nents. These land plants sud­denly ap­peared along with fig trees, mag­no­lias, and tulip trees. Soon af­ter this time fig trees, bread­fruit trees, and palms over­spread Eu­rope and the west­ern plains of North Amer­ica. No new land an­i­mals ap­peared.

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.

60:3.19Great plant-life evo­lu­tion was tak­ing place. Among the land plants the angio­sperms pre­dom­i­nated, and many pres­ent-day trees first ap­peared, in­clud­ing beech, birch, oak, wal­nut, sycamore, maple, and mod­ern palms. Fruits, grasses, and ce­re­als were abun­dant, and these seed-bear­ing grasses and trees were to the plant world what the an­ces­tors of man were to the an­i­mal world—they were sec­ond in evo­lu­tion­ary im­por­tance only to the ap­pear­ance of man him­self. Sud­denly and with­out pre­vi­ous gra­da­tion, the great fam­ily of flow­er­ing plants mu­tated. And this new flora soon over­spread the en­tire world.

60:3.2060,000,000 years ago, though the land rep­tiles were on the de­cline, the di­no­saurs con­tin­ued as monar­chs of the land, the lead now be­ing taken by the more ag­ile and ac­tive types of the smaller leap­ing kan­ga­roo va­ri­eties of the car­niv­o­rous di­no­saurs. But some­time pre­vi­ously there had ap­peared new types of the her­biv­o­rous di­no­saurs, whose rapid in­crease was due to the ap­pear­ance of the grass fam­ily of land plants. One of these new grass-eat­ing di­no­saurs was a true quadruped hav­ing two horns and a cape­like shoul­der flange. The land type of tur­tle, twenty feet across, ap­peared as did also the mod­ern croc­o­dile and true snakes of the mod­ern type. Great changes were also oc­cur­ring among the fishes and other forms of ma­rine life.

60:3.21The wad­ing and swim­ming pre­birds of ear­lier ages had not been a suc­cess in the air, nor had the fly­ing di­no­saurs. They were a short-lived species, soon be­com­ing ex­tinct. They, too, were sub­ject to the di­no­saur doom, de­struc­tion, be­cause of hav­ing too lit­tle brain sub­stance in com­par­i­son with body size. This sec­ond at­tempt to pro­duce an­i­mals that could nav­i­gate the at­mo­sphere failed, as did the abortive at­tempt to pro­duce mam­mals dur­ing this and a pre­ced­ing age.

60:3.2255,000,000 years ago the evo­lu­tion­ary march was marked by the sud­den ap­pear­ance of the first of the true birds, a small pi­geon­like crea­ture which was the an­ces­tor of all bird life. This was the third type of fly­ing crea­ture to ap­pear on earth, and it sprang di­rectly from the rep­til­ian group, not from the con­tem­po­rary fly­ing di­no­saurs nor from the ear­lier types of toothed land birds. And so this be­comes known as the age of birds as well as the de­clin­ing age of rep­tiles.

60:4.1The great Cre­ta­ceous pe­riod was draw­ing to a close, and its ter­mi­na­tion marks the end of the great sea in­va­sions of the con­ti­nents. Par­tic­u­larly is this true of North Amer­ica, where there had been just twenty-four great in­un­da­tions. And though there were sub­se­quent mi­nor sub­mer­gences, none of these can be com­pared with the ex­ten­sive and lengthy ma­rine in­va­sions of this and pre­vi­ous ages. These al­ter­nate pe­ri­ods of land and sea dom­i­nance have oc­curred in mil­lion-year cy­cles. There has been an age­long rhythm as­so­ci­ated with this rise and fall of ocean floor and con­ti­nen­tal land lev­els. And these same rhyth­mi­cal crustal move­ments will con­tinue from this time on through­out the earth’s his­tory but with di­min­ish­ing fre­quency and ex­tent.

60:4.2This pe­riod also wit­nesses the end of the con­ti­nen­tal drift and the build­ing of the mod­ern moun­tains of Uran­tia. But the pres­sure of the con­ti­nen­tal masses and the thwarted mo­men­tum of their age­long drift are not the ex­clu­sive in­flu­ences in moun­tain build­ing. The chief and un­der­ly­ing fac­tor in de­ter­min­ing the lo­ca­tion of a moun­tain range is the pre-ex­is­tent low­land, or trough, which has be­come filled up with the com­par­a­tively lighter de­posits of the land ero­sion and ma­rine drifts of the pre­ced­ing ages. These lighter ar­eas of land are some­times 15,000 to 20,000 feet thick; there­fore, when the crust is sub­jected to pres­sure from any cause, these lighter ar­eas are the first to crum­ple up, fold, and rise up­ward to af­ford com­pen­satory ad­just­ment for the con­tend­ing and con­flict­ing forces and pres­sures at work in the earth’s crust or un­der­neath the crust. Some­times these up­thrusts of land oc­cur with­out fold­ing. But in con­nec­tion with the rise of the Rocky Moun­tains, great fold­ing and tilt­ing oc­curred, cou­pled with enor­mous over­thrusts of the var­i­ous lay­ers, both un­der­ground and at the sur­face.

60:4.3The old­est moun­tains of the world are lo­cated in Asia, Green­land, and north­ern Eu­rope among those of the older east-west sys­tems. The mid-age moun­tains are in the cir­cum­pa­cific group and in the sec­ond Eu­ro­pean east-west sys­tem, which was born at about the same time. This gi­gan­tic up­ris­ing is al­most ten thou­sand miles long, ex­tend­ing from Eu­rope over into the West In­dies land el­e­va­tions. The young­est moun­tains are in the Rocky Moun­tain sys­tem, where, for ages, land el­e­va­tions had oc­curred only to be suc­ces­sively cov­ered by the sea, though some of the higher lands re­mained as is­lands. Sub­se­quent to the for­ma­tion of the mid-age moun­tains, a real moun­tain high­land was el­e­vated which was des­tined, sub­se­quently, to be carved into the pres­ent Rocky Moun­tains by the com­bined artistry of na­ture’s el­e­ments.

60:4.4The pres­ent North Amer­i­can Rocky Moun­tain re­gion is not the orig­i­nal el­e­va­tion of land; that el­e­va­tion had been long since lev­eled by ero­sion and then re-el­e­vated. The pres­ent front range of moun­tains is what is left of the re­mains of the orig­i­nal range which was re-el­e­vated. Pikes Peak and Longs Peak are out­stand­ing ex­am­ples of this moun­tain ac­tiv­ity, ex­tend­ing over two or more gen­er­a­tions of moun­tain lives. These two peaks held their heads above wa­ter dur­ing sev­eral of the pre­ced­ing in­un­da­tions.

60:4.5Bi­o­log­i­cally as well as ge­o­log­i­cally this was an event­ful and ac­tive age on land and un­der wa­ter. Sea urchins in­creased while corals and crinoids de­creased. The am­monites, of pre­pon­der­ant in­flu­ence dur­ing a pre­vi­ous age, also rapidly de­clined. On land the fern forests were largely re­placed by pine and other mod­ern trees, in­clud­ing the gi­gan­tic red­woods. By the end of this pe­riod, while the pla­cen­tal mam­mal has not yet evolved, the bi­o­logic stage is fully set for the ap­pear­ance, in a sub­se­quent age, of the early an­ces­tors of the fu­ture mam­malian types.

60:4.6And thus ends a long era of world evo­lu­tion, ex­tend­ing from the early ap­pear­ance of land life down to the more re­cent times of the im­me­di­ate an­ces­tors of the hu­man species and its col­lat­eral branches. This, the Cre­ta­ceous age, cov­ers fifty mil­lion years and brings to a close the pre­mam­malian era of land life, which ex­tends over a pe­riod of one hun­dred mil­lion years and is known as the Meso­zoic.

60:4.7[Pre­sented by a Life Car­rier of Neb­a­don as­signed to Sa­ta­nia and now func­tion­ing on Uran­tia.]

• chalk

61:1.13Con­sid­er­able foraminiferal lime­stone was de­posited in Eu­ro­pean wa­ters. To­day this same stone is el­e­vated to a height of 10,000 feet in the Alps, 16,000 feet in the Hi­malayas, and 20,000 feet in Ti­bet. The chalk de­posits of this pe­riod are found along the coasts of Africa and Aus­tralia, on the west coast of South Amer­ica, and about the West In­dies.