Branner : Geoi.ogv of Alagoas, Brazil. 



13 



South of Marcencrio is an fnibaNinent in wliicli tlu- dark shales are 

 exposed at low water and i^artly covered by a coral-reef. The following 

 dips were observed here: lo° n. 39° w. ; 13° n. 57° w. ; 12° n. 25° w., always 

 landward and toward the hills which follow the coast. 



Fig. 9. Geological section south of the Marcenerio embayment showing the 

 bituminous shales dipping landward and overgrown with a coral reef. 



At the Barra do Passo, known also as the Barro do Camaragibe, there 

 are ^ome good exposures of dark bituminous shales interbedded with 

 sandstones on the sea-shore near the town. The dips are likewise toward 

 the hills that lie to the landward of the town. 



Just south of the Camaragibe at a bluff, known as the Morro de Camara- 

 gibe, are some of the most interesting exposures to be seen on the coast of 



Fig. 10. Section showing the landward dip of the shales at Camaragibe. 



Alagoas. The bluflfs are from 75 to 90 meters high, and the upper layers 

 are the highly colored and mottled beds so characteristic of this part of 

 the Brazilian coast. At the base of the bluff, however, there are exposed, 

 especially at low tide, a series of alternating sandstones and shales of a 

 dull gray color. The lowest exposed beds of the series are cut oft' by the 



