Studies for Students 



RELATIONS BETWEEN CLIMATE AND TERRESTRIAL 



jyY.VO'^lT^— Concluded 



JOSEPH BARRELL 



Yale University, New Haven, Conn. 



Part III. Relations of Climate to Stream Transportation 



Introduction. 



Eflfects of stream transportation. 



Laboratory experiments and lavi^s of river action. 



Discussion of the data regarding transportation. 

 Preliminary inductions. 

 Relations of stable climates to transportation. 



Deductive conclusions with confirmatory illustrations. 

 Effects of varying climates upon transportation. 



Climatic change from semi-arid to rainy. 



Climatic change from rainy to semi-arid. 



Climatic changes due chiefly to temperature. 

 Conclusion. 



Conglomerates and sandstones of marine, tectonic, and climatic origin. 



Introduction 



It has been seen that climate exerts a primary control, only sub- 

 ordinate to topography, upon the rate and character of erosion on 

 the one hand and on the other upon the chemical, structural, and 

 organic characteristics developed in subaerial sedimentation. Between 

 erosion and sedimentation intervenes transportation and the ques- 

 tions arise : To what extent is the carrying power of rivers dependent 

 upon climate? To what degree may the ordinary stratigraphic 

 textural variations between succeeding strata of clay, sand, and gravel 

 be due not only to shiftings of currents and tectonic movements, but 

 to cHmatic variations as well ? 



In a general way the influence of climate upon erosion and upon 

 deposition is readily recognized and upon closer examination the 



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