Waring: Geology of Northeastern Brazil. 203 



inland edge of the coastal belt of sedimentary rocks is reached near 

 Villa Nova, where gneiss is first exposed striking about S. 15° VV., with 

 vertical dip. In the higher land between Villa Nova and Nova Cruz 

 granite is exposed, but at the latter place and thence southward to 

 Independencia gneiss is fairly continuously exposed, with constant 

 south-southwest strike and nearly vertical dip. At Independencia 

 the schists dip 45° to the southeast. East of the railway, toward 

 Mamanguape, the strike changes to northwest, with steep dip to the 

 northeast. Near Mamanguape there is an intrusion of granite, 

 which is in evidence eastward to the eastern part of the city, where it 

 is overlain by the coastal beds. Southward from Independencia the 

 strike seems to swing through south to nearly east, with some crump- 

 ling and folding between Pau Ferro and Araga. Near Araga the 

 railroad climbs from the gneissic lower lands to a tableland covered 

 with sedimentary materials, and crosses this to a short distance south 

 of Sape, where it descends again to the gneissic lowlands. At Entron- 

 camento the gneiss strikes west, with dip of 70° to the south. Thence 

 southwestward, there seems to be some crumpling between Coitezeiras 

 and Pilar, but near Itabayanna the gneiss again strikes west, with 

 steep south dip. 



About five kilometers west of Itabayanna, on the railroad to 

 Campina Grande, there are dark bands, seeiningly dikes, ten to forty 

 centimeters wide, which traverse the crumbling, disintegrated gneiss, 

 and along the grade up to Campina Grande there is much pegmatite; 

 but satisfactory observations on the structure along this line were not 

 obtained. 



Southward from Itabayanna, up grade to the summit near Rosa e 

 Silva, the gneiss dips fairly constantly southwestward. Thence down 

 to Nazareth the strike seems to vary much, as observed from the 

 train, though some of the variations indicated on the map may be 

 errors in observation. Near Nazareth granitic gneiss, somewhat 

 disintegrated, dips 20° to 30° east to northeast. At and about 

 Floresta the hills are capped by sedimentary beds. Thence to Recife 

 the strike of the crystalline rocks seems to become more uniformly 

 westward. 



Salient Features of the Bedrock Structure in the North. It is fully 

 realized that observations of strike and dip along a few widely separ- 

 ated lines in a region of intense folding may be susceptible of various 

 interpretations, and that conclusions drawn from such scanty evidence 



