Sediment-infill volcanic breccia from the Neoarchean Shimoga greenstone terrane,western Dharwar Craton: Implications on pyroclastic volcanism and sedimentation in an active continental margin |
| |
| Institution: | 1. National Geophysical Research Institute (Council of Scientific and Industrial Research), Uppal Road, Hyderabad 500 007, India;2. Department of Geology, University of Calcutta, 35, B.C. Road, Kolkata 700 019, India;3. School of Earth Science and Resources, China University of Geosciences, Beijing, China;4. Department of Geology, Central University of Karnataka, Gulbarga, India;1. Department of Earth and Environment Science, National Chung-Cheng University, 168 University Road, San-Hsing, Min-Hsiung, Chia-Yi, Taiwan;2. Clay and Interface Mineralogy, RWTH Aachen University, 52056 Aachen, Germany;3. Department of Earth Sciences, Okayama University, Okayama 700-8530, Japan;4. Department of Civil & Architectural Engineering, Shikoku Electric Power Co. Inc, 2-5, Marunouchi, Takamatsu 760-8573, Japan;5. Ehime Branch, Naiba Co. Ltd., 67-2, Doida-cho, Matsuyama 790-0056, Japan;6. Tokyo Branch, Hanshin Consultants Co. Ltd., 4, Kanda-nishifukuda-cho, Chiyoda-ku 101-0037, Japan;1. College of Earth Sciences, Jilin University, Changchun 130061, China;2. Department of Earth Sciences, The University of Hong Kong, Pokfulam Road, Hong Kong;1. Institute of Earth Sciences, Academia Sinica, Taipei, Taiwan;2. Taiwan Volcano Observatory at Tatun, Ministry of Science and Technology, Taipei, Taiwan;3. Laboratory of Seismology and Physics of Earth’s Interior, School of Earth and Space Sciences, University of Science and Technology of China, Hefei, Anhui, China;4. Department of Geology, Chinese Culture University, Taipei, Taiwan;5. Institute of Applied Geosciences, National Taiwan Ocean University, Keelung, Taiwan;6. Department of Natural Resources and Environmental Studies, National Dong Hwa University, Hualien, Taiwan;1. Department of Geology and Geophysics, Indian Institute of Technology (IIT), Kharagpur 721302, India;2. Institute of Geological Sciences, University of Bern, Baltzerstrasse 1+3, 3012 Bern, Switzerland;3. 3S–4/113, Niladrivihar, Chandrasekharpur, Bhubaneshwar 751021, India;1. Institute of Geophysics, China Earthquake Administration, 100081 Beijing, China;2. Chinese Academy of Geological Science, 100037 Beijing, China;3. School of Earth Sciences and Resources, China University of Geosciences, 100083 Beijing, China;1. Department of Geology, University of Calcutta, 35, Ballygunge Circular Road, Kolkata 700 019, India;2. Department of Lithospheric Research, University of Vienna, Althanstrasse 14, A-1090 Vienna, Austria;3. Natural History Museum, Burgring 7, A-1010 Vienna, Austria;4. CSIR-National Geophysical Research Institute, Uppal Road, Hyderabad 500 007, India |
| |
| Abstract: | We report sediment-infill volcanic breccia from the Neoarchean Shimoga greenstone belt of western Dharwar Craton which is associated with rhyolites, chlorite schists and pyroclastic rocks. The pyroclastic rocks of Yalavadahalli area of Shimoga greenstone belt host volcanogenic Pb–Cu–Zn mineralization. The sediment-infill volcanic breccia is clast-supported and comprises angular to sub-angular felsic volcanic clasts embedded in a dolomitic matrix that infilled the spaces in between the framework of volcanic clasts. The volcanic clasts are essentially composed of alkali feldspar and quartz with accessory biotite and opaques. These clasts have geochemical characteristics consistent with that of the associated potassic rhyolites from Daginkatte Formation. The rare earth elements (REE) and high field strength element (HFSE) compositions of the sediment-infill volcanic breccia and associated mafic and felsic volcanic rocks suggest an active continental margin setting for their generation. Origin, transport and deposition of these rhyolitic clasts and their aggregation with infiltrated carbonate sediments may be attributed to pyroclastic volcanism, short distance transportation of felsic volcanic clasts and their deposition in a shallow marine shelf in an active continental margin tectonic setting where the rhyolitic clasts were cemented by carbonate material. This unique rock type, marked by close association of pyroclastic volcanic rocks and shallow marine shelf sediments, suggest shorter distance between the ridge and shelf in the Neoarchean plate tectonic scenario. |
| |
| Keywords: | Sediment-infill volcanic breccia Pyroclastic rocks Active continental margin Shimoga greenstone belt Dharwar Craton |
| 本文献已被 ScienceDirect 等数据库收录！ |
|
