C. TV. Honess — Stanley Shale of Oklahoma. 79 



bottom of the Stanley — a silt which was more sandy at 

 certain periods than others by reason of the well-known 

 conditions controlling all large rivers, and one which was 

 rich in organic matter at all times. 



The ripple marks, rill marks, and cross-bedding 

 thronghont the succession would indicate that mud flats 

 were repeatedly if not almost continuously a feature of 

 the delta on which the ancient river laid these sediments. 

 The silts, sands, and muds were evidently washed around 

 and shifted about on the flats, re-sorted and finally depos- 

 ited in the ripple-marked and cross-bedded condition in 

 which we find them. 



That fragments of plants, pieces of wood, bark, leaves, 

 etc., should be washed down a river and become buried in 

 the sands is, of course, a well-known fact and in accord 

 with the facts of the Stanley sediments. 



It should also be expected that a great delta deposit at 

 the mouth of a large river such as it appears the Stanley 

 must have been would from time to time, especially during 

 periods of storms and rough sea, be peopled by marine 

 animals. These doubtless would not move voluntarily 

 from their habitats to fresh water but might easily be 

 washed along by littoral currents and heaved shoreward 

 by storm waves. Thus one may account for the few 

 brachiopods and other animals found. With reference to 

 the bryozoa and other fossils found at the Little River 

 locality special mention should be made of the fact that 

 this fauna occurs in a horizon about 3 inches thick com- 

 posed chiefly of quartz gravel whose grains average about 

 2 mm. and that the fossils are broken to bits. Regard- 

 ing the character of this fossiliferous layer Professor 

 Schuchert says : 



"The physical character of the rock of localities 943 and 944 

 leads me to the following physiographic and geologic conclusion. 

 The material came in the main from a granitic country, though I 

 think there were present also metamorphic rocks, for there 

 appears to be present considerable micaceous schist. This 

 schist is still in ang-ular pieces and larger than the quartz peb- 

 bles, indicating shorter transportation. In addition, there is 

 much black shale present, some of which is also metamorphosed 

 but apparently not all of it. The quartz pebbles are fairly weU 

 rounded and with the sand appear to have come a much longer 

 distance than the shale and schist. There are also rounded 

 pieces of garnet present." 



