210 GEOLOGY OF THE M"AEEAGAE^8BTT BASm. 



remaining distance to the Attleboro synclinal axis. Assuming 75^ as the 

 average dip across these upturned beds, which have a breadth of outcrop of 

 about 11,900 feet, we obtain about 11,500 as a measurement of the thick- 

 ness Again this is a minimum estimate, reaching only from the top of the 

 highest remaining beds in the synclinal trough to the lowest exposures in 

 a broken anticlinal arch. 



These measurements, taken in the northern part of the basin, across 

 comparatively simple great folds, enforce the conviction that the strata now 

 rexnaining in the deeper, central portion of this basin can not be less than 

 12,000 feet in thickness. This estimate agrees closely with that given for 

 the Carboniferous strata of the Joggins section in Nova Scotia, which are 

 about 13,000 feet thick. 



