Historical Geology Understanding Our Planet\'s Past

The giant herbivorous dinosaurs such as apathosaurs and stegosaurs (Fig. 153) developed a large stomach to digest the tough, fib ...

Many families of large dinosaurs, including apathosaurs, stegosaurs, and allosaurs (Fig. 154) became extinct at the end of the J ...

larger continents. Millions of years later, the continents rifted apart, and the chasms filled with seawater to form new oceans. ...

After the breakup, the continents traveled in spurts rather than drifting apart at a constant speed. The rate of seafloor spread ...

middle of Wyoming. The Nevadan orogeny produced the Sierra Nevada in California (Fig. 156) during the middle to late Jurassic. T ...

The vast majority of marine species live on continental shelves, shallow- water portions of islands, and subsurface rises genera ...

accumulations of marine sediments eroded from the Cordilleran highlands to the west were deposited on the terrestrial redbeds of ...

T his chapter examines the life-forms and landforms of the Cretaceous period and the extinction of the dinosaurs.The Cretaceous, ...

THE AMMONITE ERA Coral reefs were the most widespread during the Cretaceous, ranging 1,000 miles away from the equator. In contr ...

Free ebooks ==> http://www.Ebook777.com with certain rare members adapted to life in freshwater. They have existed since the ...

The cephalopods were the most spectacular, diversified, and successful marine invertebrates of the Mesozoic seas. The nautiloids ...

ammonoids ideal for dating Paleozoic and Mesozoic rocks. Throughout the Mesozoic, ammonite shell designs steadily improved.The c ...

sive predators might have caused the extinction of most ammonite species before the Cretaceous was over. All shelled cephalopods ...

elements that enabled the advanced plants to cope with drought conditions. Before such vessels appeared, plants were restricted ...

The cone-bearing plants prominent during the entire Mesozoic occu- pied only a secondary r ole during the Cenozoic.Tropical vege ...

ing large quantities of carbon dioxide from the atmosphere, angiosperms caused a drop in global temperatures. Forests of broad-l ...

A region from eastern Utah to the Texas panhandle that deformed during the late Paleozoic Ancestral Rockies orogeny was complete ...

evolved by a process of upthrusting similar to the plate collision and subduc- tion that raised the Andes of Central and South A ...

120 million years ago, an extraordinary burst of submarine volcanism struck the Pacific Basin. It released vast amounts of gas-l ...

Mountains, which are among the most extensive coal beds in the world. Alliga- tors and crocodiles lived in the high northern lat ...