RANDOM, A PBE-CAMBKIAN UPPER ALGONKIAN TERRANE 5 



rane is faulted out of sight. On the opposite or eastern side of the synclinal 

 basin holding the Cambrian rocks the Random terrane appears to be much thicker, 

 although folded and repeated several times. On the east side of Trinity bay, at 

 Hearts Delight harbor, I measured the following section of the Random terrane 

 without reaching down to the white quartzite which is above the Signal Hill con- 

 glomerate : 



Cambkian ; basal conglomerate. 



Random terrane: Feet 



1. Fine silieious conglomerate, passing down into thick bedded gray and greenish gray- 



compact, hard sandstones 45 



2. Silieious and sandy shales, flaggy sandstones with thick layers of sandstone in the 



upper 65 feet ; traces of annelid trails occur on the surface of the shaly beds 225 



3. Massive bedded dark gray quartzitic sandstones with a few bands of shaly sand- 



stone ; strike at base, north 50 degrees east ; dip, 75 degrees southwest 700 



Concealed by drift. 



The Random terrane is probably 1,000 feet, and possibly more, in thickness. It 

 fills in a portion, if not all, of the sap between the Signal Hill conglomerate and 

 the Cambrian. The erosion preceding the deposition of the Cambrian about Trin- 

 ity bay appears to have been slight, as the conglomerate resting on the Random 

 is rarely over 18 inches in thickness, and usually much less. This, however, is not 

 a safe deduction, as great erosion may leave but slight trace, either in conglomerates 

 or in apparent nonconformity in the dip or strike of the strata. 



The Random terrane is considered to be the upper member of the Avalon series.* 

 Animal life existed during the deposition of a portion of it, as is evidenced by 

 clearly marked annelid trails. A collection of the form known as Aspidella terra- 

 novica was made from the Momable terrane of the Avalon series. It proved the 

 supposed fossil to be a spherulitic concretion, and this removes it from among the 

 possible pre-Cambrian forms of life. 



PRE-CAMBRIAN PETROGRAPH1C PROVINCE OF THE FOX RIVER VALLEY, 



WISCONSIN 



BY WM. H. HOBBS AND C. K. LEITH 



WITH ANALYSIS BY W. W. DANIELLS 



The next paper was presented by the author, as follows : 



AGE AND DEVELOPMENT OF THE CINCINNATI ANTICLINE 

 BY AUG. F. FOERSTE 



Remarks were made by H. S. Williams and J. M. Clarke. 



In the-absence of the author, the following paper was read by title : 



LOWER DEVONIAN ASPECT OF THE LOWER HELDERBERG AND ORISKANY 



FORMA TIONS 



BY CHARLES SCHUCHERT 



This paper is printed in full in this volume. 



*See Bull. Geol. Soc. Am., vol. 10, p. 219. 



