58 J. C. BRANNER — GEOLOGY OF NORTHEAST COAST OP BRAZIL 



rocks are reported to be exposed at Batalha on the Rio Parahyba, within 

 the area covered by the sedimentary beds. 



8. It seems probable that the sediments all dip gently eastward, so that 

 the Cretaceous beds are occasionally exposed inland, while they are not 

 visible on the coast. 



9. The watershed between the Parahyba valley and that of the. Rio 

 Mamanguape is of crystalline rocks,' thinly covered with sedimentary 

 beds. The waterworn material of the plateau is coarser on the lower 

 slopes than on the top of the plain. 



10. The Cretaceous beds rest on schists and other crystalline rocks. 



11. The schists are nearly everywhere cut with quartz veins; these 

 veins are generally less than half a meter in thickness. 



12. The schists are not much wrinkled, but they stand at high angles — 

 from 50 to 75 degrees. 



13. The crystalline rocks are all more or less decomposed, so that many 

 of the railway cuts through them have been made with picks. In some 

 places they have been blasted. The cuts in the hard rocks, however, are 

 nowhere more than 4 or 5 meters deep. 



14. In the vicinity of Independencia the crystalline rocks contain dikes 

 of dark diabase-like eruptives. 



15. The crystalline rocks of the interior have been called Laurentian 

 by Williamson, but while they lithologically resemble some of the so- 

 called Laurentian beds of Canada, no trustworthy evidence has been 

 found of their age or ages. 



16. The general topography shows that there has been a late depres- 

 sion of this coast region ; that the water filled the valleys near the coast, 

 and that these valleys afterward silted up and are now partly occupied 

 by mangrove swamps. This history is borne out also by the soundings 

 made in the mud of the mangrove swamps near Parahyba. 



17. The depression of the coast was more than 12 meters. 



18. The remains of extinct Pleistocene vertebrates are reported from 

 the interior of the state. 



19. Fossils and limestones are reported from the interior of the state, 

 but no facts are available to indicate whether these limestones and fos- 

 siliferous beds belong to the Cretaceous or with the Paleozoic series. The 

 lithologic character of some of the limestones and the geographic posi- 

 tion of the rocks suggest that they are Cretaceous. 



Geology along the Pernambuco Coast South of Recife 



location and character of the exposures 



In July, 1899, I made a trip on foot along the coast south of Pernam- 

 buco, and some of the observations on the geology are appropriate here 



