DOI: 10.1007/s00531-013-0870-z
Scopus记录号: 2-s2.0-84878932503
论文题名: The relationship between carbonate facies, volcanic rocks and plant remains in a late Palaeozoic lacustrine system (San Ignacio Fm, Frontal Cordillera, San Juan province, Argentina)
作者: Busquets P. ; Méndez-Bedia I. ; Gallastegui G. ; Colombo F. ; Cardó R. ; Limarino O. ; Heredia N. ; Césari S.N.
刊名: International Journal of Earth Sciences
ISSN: 14373254
出版年: 2013
卷: 102, 期: 5 起始页码: 1271
结束页码: 1287
语种: 英语
英文关键词: Argentina Frontal Cordillera
; Late Palaeozoic
; Microbial lacustrine carbonates
; Palaeosols
; Permineralized plants
; Volcanic rocks
Scopus关键词: carbonate
; foreland basin
; geoaccumulation
; ignimbrite
; lacustrine deposit
; lava flow
; paleosol
; Paleozoic
; plant
; pyroclastic deposit
; pyroclastic flow
; sandstone
; volcanic ash
; volcanic rock
; Argentina
; Misiones [Argentina]
; San Ignacio
; San Juan [Argentina]
; algae
; Cyanobacteria
; Trachytes
英文摘要: The San Ignacio Fm, a late Palaeozoic foreland basin succession that crops out in the Frontal Cordillera (Argentinean Andes), contains lacustrine microbial carbonates and volcanic rocks. Modification by extensive pedogenic processes contributed to the massive aspect of the calcareous beds. Most of the volcanic deposits in the San Ignacio Fm consist of pyroclastic rocks and resedimented volcaniclastic deposits. Less frequent lava flows produced during effusive eruptions led to the generation of tabular layers of fine-grained, greenish or grey andesites, trachytes and dacites. Pyroclastic flow deposits correspond mainly to welded ignimbrites made up of former glassy pyroclasts devitrified to microcrystalline groundmass, scarce crystals of euhedral plagioclase, quartz and K-feldspar, opaque minerals, aggregates of fine-grained phyllosilicates and fiammes defining a bedding-parallel foliation generated by welding or diagenetic compaction. Widespread silicified and silica-permineralized plant remains and carbonate mud clasts are found, usually embedded within the ignimbrites. The carbonate sequences are underlain and overlain by volcanic rocks. The carbonate sequence bottoms are mostly gradational, while their tops are usually sharp. The lower part of the carbonate sequences is made up of mud which appear progressively, filling interstices in the top of the underlying volcanic rocks. They gradually become more abundant until they form the whole of the rock fabric. Carbonate on volcanic sandstones and pyroclastic deposits occur, with the nucleation of micritic carbonate and associated production of pyrite. Cyanobacteria, which formed the locus of mineral precipitation, were related with this nucleation. The growth of some of the algal mounds was halted by the progressive accumulation of volcanic ash particles, but in most cases the upper boundary is sharp and suddenly truncated by pyroclastic flows or volcanic avalanches. These pyroclastic flows partially destroyed the carbonate beds and palaeosols. Microbial carbonate clasts, silicified and silica-permineralized tree trunks, log stumps and other plant remains such as small branches and small roots inside pieces of wood (interpreted as fragments of nurse logs) are commonly found embedded within the ignimbrites. The study of the carbonate and volcanic rocks of the San Ignacio Fm allows the authors to propose a facies model that increases our understanding of lacustrine environments that developed in volcanic settings. © 2013 Springer-Verlag Berlin Heidelberg. URL: https://www.scopus.com/inward/record.uri?eid=2-s2.0-84878932503&doi=10.1007%2fs00531-013-0870-z&partnerID=40&md5=e067f2435fcd1cb8c7334ca09d175085
Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/70547
Appears in Collections: 影响、适应和脆弱性 气候减缓与适应
There are no files associated with this item.
作者单位: Departament d'Estratigrafia, Paleontologia i Geociències Marines, Universitat de Barcelona, C/Martí i Franqués s/n, 08028 Barcelona, Spain; Departamento de Geología, Universidad de Oviedo, C/Jesús Arias de Velasco s/n, 33005 Oviedo, Spain; Instituto Geológico y Minero de España, C/Matemático Pedrayes 25, 33005 Oviedo, Spain; Servicio Geológico y Minero Argentino, C/Sargento Cabral 685, 5400 Oeste, San Juan, Argentina; Departamento de Ciencias Geológicas, Universidad de Buenos Aires, C1428EHA Buenos Aires, Argentina; Museo de Ciencias Naturales B. Rivadavia, Avenida Ángel Gallardo 470, 1405 Buenos Aires, Argentina
Recommended Citation:
Busquets P.,Méndez-Bedia I.,Gallastegui G.,et al. The relationship between carbonate facies, volcanic rocks and plant remains in a late Palaeozoic lacustrine system (San Ignacio Fm, Frontal Cordillera, San Juan province, Argentina)[J]. International Journal of Earth Sciences,2013-01-01,102(5)