BULLETIN OF THE GEOLOGICAL SOCIETY OF AMEftiCA 

 Vol. 17, pp. 567-636 December 31. 1906 



TYPES OF SEDIMENTAEY OVERLAP* 



BY AMADEUS W. GRABAU 



(Presented in abstract before the Society December 29, 1905) 



CONTENTS 



Page 



Introduction 568 



Classification of types of overlap 569 



Irregular overlap 569 



Progressive overlap 569 



Progressive overlap in marine series 569 



Transgressive overlap 570 



Application of the principle of transgressive overlap in the sedimentary 



series 571 



The basal Paleozoic series 571 



General character of the overlap 571 



Newfoundland 571 



New Brunswick 572 



Northern Appalachian area 574 



Southern Appalachian area 575 



South central section 578 



The Upper Mississippi area 580 



Subdivisions 580 



Lake Superior sandstone 582 



Encampement d'Ours 582 



Western Adirondacks and Canada 584 



Basal Paleozoic beds of the Rocky Mountain region 585 



Foreign examples 587 



The basal Mesozoic series 589 



The Central area \ 589 



The West Coast transgression 590 



Foreign examples 591 



Progressive overlap and the Black Shale problem 593 



Statement of the principle of the regressive overlap 613 



Compound regressive and transgressive overlap 615 



Statement of the principles 615 



Application of the principles 616 



The Saint Peter sandstone 616 



The Dakota sandstone problem • 620 



* This paper, under the title "The interpretation of stratigraphic series by the prin- 

 ciples of sedimentary overlap," was awarded the Walker first prize by the Boston 

 Society of Natural History in May, 1906. 



LIU— Bull. Geol. Soc. Am., Vol. 17, 1905 (567) 



