Geochemistry and petrology of rift-related mafic sills and arc-related Gabbro-Diorite bodies, Northe

• 作者: S. M. Niktabar N. Rashidnejad Omran
• 学科: 地球科学
• 关键词: Sills Rizu formation Rift Volcanic arc
• 年，卷（期）: 2022,（2）
• 页码范围: 180-192
• 页数: 12页
• 语种: 英文
• DOI: 10.1007/s11631-017-0191-1

摘要

Two types of mafic intrusions have been recognized in the north of the Bafq district, Central Iran. A number of olivine-gabbroic to gabbroic sills intruded the Rizu Formation, comprised of alternating carbonate and volcanic rocks. Mineralogical data show that olivine ? pyroxene ? brown amphibole (kaersutite) ? calcic plagioclase ? opaque comprise the olivine-gabbroic rocks, and intermediate (or sodic) plagioclase ? altered pyroxene and altered amphibole to biotite ? opaque minerals the gabbroic rocks. Both rock types have shown within-plate and alkaline characters and have been presumed to be related to rift formation. The mafic-alkaline magma source of the sills is proposed to have been derived from enriched mantle. Regionally, two Gabbro-Diorite intrusions have been identified in the metamorphic complexes. Mineralogical data suggest that the pyroxene+amphibole (hornblende)+plagioclase+biotite+opaque minerals formed the gabbro to diorite intrusions. These rocks have shown characteristics of calc-alkaline and volcanic arc magmatism.