NORTHEASTERN BRAZIL. Sinc e the Jurass ic, the area of Northeastern Brazil was affected by several magmatic events , bot h intrus ive and effusive ones. The ages of the igneous bodi es are not perfectly known, but it can be stated that some sedimentary basins accomodated prominent part of the geolog ic record from the igneo us acti vity. The area north to the 8 0 S parall el was more intenselly affected, comprising depo sits in the Parn afba, Potiguar, and Lavras da Mangabeira basins. The occurrences are relativ ely scattered on Precambrian area s, restri cted to zones very far from the Sao Franci sco Cra ton. Th ere are three main age gro ups. Th e Jure-Cretaceous bodies (pre-A ptian) are composed o f tholeiitic basalts normally without olivine. T he Albian and Tertiary ones usuall y exhibit modal olivine and alkaline com position. It seems that a quiet phase occurred comprising the Neocretaceou s and the Paleocen. Based on aeromagnetic and geolog ic ma ps at a reg iona l scale, It has been POSSible to show that some areas were strongly atrected by igneous activity. Part of them can be followed along hundreds o fk ilo me ters, in a shape of igneous alll gnements. The most expres sive are the Rio Ceard-Mirim, the Mecejena-Pemando de Noro nha, both trending E-W. and Maca u-Quelmadas, trending NNW. Th e former is related to Neocomian , and the oth ers belon g to the Tertiary. T here are no Quaternary igneous activity in the co ntinental area , but some oceanic islands wer e evolved until the end of the tertiary. RES UM O A partir do Juras sico , 0 Nord este do Brasil sofreu diverso s eve ntos magmati cos, intrusive s e efusivos, cu ias idades sao ainda mal conhecidas. Seus reglstros sao ma is bem defi nidos acima do parale lo de 8°S, conce ntran dose em algumas bacias sedimentares, como as do Parnaiba, Potiguar e Lavras da Mangabeira. Nas Areas pre-cambrianas, as ocorrencias sao relativam en te dispersas, restr ing lndo-se a POff;6eS afastadas do Craton do Sao Francisco. 0 presente tra balho constltui u ma slntese de co nhecimentos que integ ra os dados da Iiteratura e dos mapas dispo nfveis sobr e essa atividade fgnea mesoz6ico-cenoz6ica no Nordeste Orie nta l. Por me io de uma co mparecao das intorm acoes coletadas com a expressao geoffsica dos reglstros, novas ocorrencias de corpos Igneos sao detectada s e seu signifi cado ediscutido. 0 estudo procura contri buir para se con hecer melhor os estagios da Ativa~ao Meso z6ica na regi lo. Tres grupos principais de idade sao conheci dos. Nas ma nifestacoe s j uro-cretdceas (pre-aptianas) predominam basaltos toleftico s, ger almente nao-o livfnicos, enquanto os albianos e tercidri os geratmente apresentam olivina moda l e co mpos icao alcaltna. Aparentemente, hou ve uma fase de quietude compreendendo 0 Neocretaceo e 0 Paleoceno. Enfatiza-se a exlstencia de do is alinhamento s de corpos Igneos: os dique s do Magmatismo Rio Ceara-Miri m (J-K) , dispostos segu ndo E-W, e os corpos intrusive s e extruslvos vincu lados a Formacao Macau (Eoce no-Mloceno), que se alinham segu...
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