Neoproterozoic oceans in the Ribeira Belt (southeastern Brazil): The Pirapora do Bom Jesus ophiolitic complex

• 来源期刊: 幕-国际地学杂志（英文版）
• 学科: 地球科学
• 年，卷（期）: 2001,（4）
• 页码范围: 245-251
• 页数: 7页
• 分类号: P5
• 语种: 英文

摘要

Within the Sao Roque Domain of the Neoproterozoic Ribeira Fold Belt (southeastern Brazil) we have identified an ophiolitic complex (Pirapora ophiolite) display ing a characteristic oceanic lithospheric stratigraphy.From bottom to top, it includes: 1) a lower crustal/upper mantle section (dunitic cumulates with chromitite-magnetite layers); 2) a lower crustal section (metagabbro and flasergabbro mafic cumulates with gabbroic pegmatoids); and 3) an upper crustal section (deformed fine-grained, greenschist facies metamafics with remains of a sheeted dike complex, pillow lavas and cherts).