BULLETIN OF THE GEOLOGICAL SOCIETY OF AMERICA 

 Vol. 25, pp. 655-744 DECEMBER 14, 1914 



MECHANICAL COMPOSITION OF CLASTIC SEDIMENTS^ 



BY JOHAN AUGUST UDDEN 



{Presented for publication hy the Society October 10, 191Jf) 



CONTENTS 



Page 



Introductory 656 



Methods of analysis 657 



Materials examined 659 



The three classes of sediments . 659 



Glacial till 659 



Water deposits 661 



General discussion 661 



Sediments in glacial waters 661 



Materials from single layers of deposits in glacial waters 662 



Terrace materials 662 



Materials from single layers in terrace sands 663 



Silts in terraces of the Mississippi 663 



Sediments in present streams 664 



Sediments in small streams 664 



Drifted sediments in large streams 665 



Silt from large streams 666 



Lake deposits 667 



Deposits in the sea. 667 



Classification 667 



Beach gravel 668 



Silts in harbors 668 



Deposits on the continental shelf in the West Atlantic 669 



Sediments on the submerged west slope of the west coast of 



America 672 



Deposits in the Bering Sea 673 



Deposits in the sea near volcanoes 674 



Deposits near the margins of ocean basins 675 



Wind deposits 676 



Classification 676 



Lag gravels 676 



Coarse drifting sand 677 



Dune sand 678 



i Manuscript received by the Secretary of the Society October 14, 1914. 

 This paper was not presented at a meeting, but has been accepted by a unanimous 

 vote of the Publication Committee for publication in the Bulletin, 



XLVII— Bull. Geol. Soc. Am., Vol. 25, 1913 (655) 



