Oil-shales and Petroleum Prospects in Brazil

Abstract

In view of the frequent occurrence of petroleum in other parts of the world, it seems odd that so large an area as is contained within the borders of Brazilshould be without this product. This apparent deficiency may be due, however, to our ignorance of the regions in which it may exist. In some places, indications point to the probable existence of petroleum in ages gone by; andwhile the presence of petroleum pools may be problematic, in several regionsconditions not unfavorable to their occurrence exist.Yet, Brazil has enormous oil resources in the rich oil-shales in differentparts of the country. Many of these shales are very rich and only suitableprocesses for the extraction of the oil are lacking. At the present time, onlya few small experimental plants are producing oil by distillation from theseshales. These plants have been the subject of recent investigations by theGeological and Mineralogical Survey, a preliminary report of which is in thehands of the printer. The only regions where studies have not been made are theupper Amazon, the Acre, the Rio Negro, and the Peruvian frontier, which reallyseems to be the most promising field for explorations of any in thecountry.In the vast plateau region of the interior north of the 20th parallel oflatitude, granites, gneiss, mica schists, and very old metamorphosedsedimentaries predominate. Later, sedimentaries occupy a minor position and, where found in the interior, represent a thin veneering resting on the olderrocks. At several places near the coast they have a greater development andcontain considerable beds of oil-shale and may, in some cases, offer conditionsfavorable for the occurrence of oil. Such deposits are found in the Permianrocks of central and southern Maranhao; in the Tertiary and Cretaceous bedsalong the coast of Alagoas Sergipe, Bahia, and perhaps farther south inEspirito Santo; and in the Parahyba embayment north of Cape Frio and in theinterior Tertiary basin of eastern Sao Paulo.AIME 065–11