Brannkk : CIeoloov of Ai.agoas, Brazil. 



11 



derived directly from the basal granites. In the section exjwsed along 

 the railway running north from Maceio the rocks seen are mostly the 

 colored sandstones, hut about a kilometer northeast of the station of 

 Utinga (Kil. 26.6) some horizontal gray shales are exposed by the side of 

 the railway. Unfortunately this exposure could not be examined for 

 fossils at the time of my visit. Further northeast along the line of the 

 railway (about Kil. 29) the railway cuts into the base of the Serra de 

 Ouro, and for two or three kilometers exposes heavy beds of decomposed 

 granite boulders Similar conglomerates are exposed less than a kilometer 

 south of the station of Cachoeira. At this last named station the granites 

 are exposed in places and continue across the entire northern part of the 

 state, so that Cachoeira marks the northwestern margin of the sedimentary 

 belt where it is crossed by the railway. 



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Cr, 



y^^^//A,, ^ok?a^ 



Fig. 7. Ideal section from Maceio to Albuquerque, 35 kilometers, along the 

 Alagoas Railway, showing the coast sediments resting on the crystalline rocks. 



The branch of the railway running from Albuquerque to Assemblea 

 passes all the way over granites and other old crystalline rocks, except for 

 a short distance between Bittencourt and Atal^ia where a deep cut exposes 

 a beautiful unconformity between the underlying granites and the inland 

 margin of the abutting sediments. 



Beds Dipping Landward. — There are certain noteworthy exceptions to 

 the horizontality of the coast sediments. At many places on the coast 

 the lowest sedimentary beds exposed are mostly shales, and these are 

 often found dipping decidedly toward the land. Good examples of the 

 landward dip of these beds are exposed on the beach at the following 

 localities beginning in the northern part of the state and following down 

 the coast. The compass bearings given are the magnetic readings. 



At the mouth of Rio Maragogy 9° 3' s. latitude, the shales are somewhat 

 wrinkled where exposed in a wave-cut bench. The dips obser\ed in the 

 shales are 10° s. 71° w. and 6° s. 31° w. These shales dip landward beneath 

 the red and mottled sandstones exposed in the hills near the coast. Just 



