A GEOLOGIST'S PARADISE 



By R. S. Bassleb 

 Head Curator, Dcpartmctit of Geology, United States National MuHeum 



[With 4 plates] 



Paradise to the geologist is not only the traditional far-away 

 heaven with its gates of pearl and jasper and streets of gold, all 

 precious minerals of interest to him, but it is also right here on 

 earth where these minerals and many interesting earth problems are 

 to be found. Ordinarily people think of Washington as a city of 

 museums and libraries and governmental activities, but here in the 

 Capital City we have one of the most favored areas of North America 

 for the study of geology — a paradise for both teacher and student. 

 Just what is geology, and why should a geologist find his paradise 

 on earth ? Geology, briefly, is the study or science of the earth and 

 its inhabitants. The period covered by this study starts from the 

 time our planet was a fiery mass revolving in its course through the 

 heavens, subject only to physical laws, on down through eons of time 

 to the present, when life has become such a predominant factor. 

 Geology is all-inclusive, not only in the length of time it covers but 

 also in the various sciences it comprises. For it embraces phases of 

 the physical sciences, such as astronomy, physics, and chemistry, con- 

 cerned mainly with early earth history, and the biological sciences, 

 zoology and botany, studies dealing with the life of the earth. 



Although a paradise for study may be found by the geologist in 

 almost any place, naturally to the specialist one region may offer 

 greater interest than another. The Bad Lands of the Dakotas — 

 lands practically barren and deeply gullied by occasional heavy 

 rains — reveal to the physiographic geologist, or student of land 

 forms, a story, to express it scientifically, of the erosion of unequally 

 resistant sedimentary rocks occurring in a semiarid region. 



On the other hand, the sturdy granites of New England tell a far 

 different story of earth history, for they were originally molten 

 rocks formed deep in the earth's crust but now exposed at the surface 

 by weathering. A striated or scratched boulder from New York 

 State brings before the student of glacial geology a vivid picture ot 

 the ice age. And so on — each section of the country has its own 

 geological formations, problems, and interest. 



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