ABSTRACTS OF PAPERS 95 



SAND RIVERS OF TEXAS AND CALIFORNIA AND SOME OF THEIR 

 ACCOMPANYING PHENOMENA 



BY ROBERT T. HILL 



(Abstract) 



(a) Certain rivers of tlie Great Plains region, interior deserts, and soutliern 

 California constitute a class for which the name "sand rivers" is proposed. 

 The Red River of Texas and the Santa Ana River of California are tjpes. 

 These are streams which deposit much of their sand load along their middle 

 courses, to be subsequently removed by wind. 



(&) The "windrow" dunes of the Red River of Texas. On the south side of 

 the Big Bend of Red River, in Wichita County, Texas, there are many elon- 

 gated sand-dunes, occurring over a wide, normally dry, second bottom of the 

 river and parallel to the stream. These are named "windrow dunes,'' owing 

 to their resemblance to windrows of a hayfield, and they are described as one 

 of the effects of disposition by the wind, after deposition on the sand flats, of 

 the load of sand rivers. 



Presented in full extemporaneously^ 



SEDIMENTATION AT THE MOUTHS OF THE MISSISSIPPI RIVER— PRELIMI- 

 NARY lUJPORT^ 



EY ARTHUR C. TROWBRIDGE 



(Ahstract) 



Two months of field-work below New Orleans in 1922 jdelded a number of 

 notes pertaining to (1) the flood of 1922, the highest water on record; (2) 

 the relations of turbidity and total load to the maintenance of navigable chan- 

 nels ; (3) the gradual closing, by deposition, of some of the mouths of Pass a 

 Loutre without permanently injuring South Pass; (4) the depth of the delta 

 material; (5) the methods and rates of delta growth; (6) the constitution of 

 the deposits on natural levees, in the passes, in the bays, and on the offshore 

 bars; (7) recent enlargement of South Pass in relation to its navigability; 

 (8) the projected opening of Southwest Pass to navigation; (9) various other 

 engineering projects in relation to sedimentation, etcetera. 



Eead l)y title. 



GEOLOGICAL MAP OF THE BUSHVELD COMPLEX, TRANSVAAL, SOUTH AFRICA 



BY CHARLES PALACHE 



{ Abstract) 



Exhibition of the map of the Bushveld Complex prepared by the Geological 

 Survey of the Union of South Africa ; explanation of some of the major fea- 

 tures of the map ; illustrations of structure and scenery of part of the region. 



Presented in abstract extemporaneously. 



Paper presented by permission of tbe U. S. district engineer in New Orleans. 



