Portal de Periódicos da CAPES

Artigo Produção Nacional Revisado por pares

BIBTEX RIS

Influence of Diagenesis On the Quality of Lower Cretaceous Pre-salt Lacustrine Carbonate Reservoirs from Northern Campos Basin, Offshore Brazil

2017; Society for Sedimentary Geology; Volume: 87; Issue: 12 Linguagem: Inglês

10.2110/jsr.2017.70

1938-3681

Ronaldo Herlinger, Eveline Ellen Zambonato, Luiz Fernando De Ros,

Geological and Geophysical Studies

Research Article| December 12, 2017 Influence of Diagenesis On the Quality of Lower Cretaceous Pre-salt Lacustrine Carbonate Reservoirs from Northern Campos Basin, Offshore Brazil Ronaldo Herlinger, Jr.; Ronaldo Herlinger, Jr. 1Petrobras S.A., Avenida República do Chile, 330, Rio de Janeiro, RJ, Brazil Search for other works by this author on: GSW Google Scholar Eveline Ellen Zambonato; Eveline Ellen Zambonato 2Petrobras S.A., Avenida Nossa Senhora da Penha, 1688, Barro Vermelho, Vitória, ES, Brazil Search for other works by this author on: GSW Google Scholar Luiz Fernando De Ros Luiz Fernando De Ros 3Instituto de Geociências, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil Search for other works by this author on: GSW Google Scholar Author and Article Information Ronaldo Herlinger, Jr. 1Petrobras S.A., Avenida República do Chile, 330, Rio de Janeiro, RJ, Brazil Eveline Ellen Zambonato 2Petrobras S.A., Avenida Nossa Senhora da Penha, 1688, Barro Vermelho, Vitória, ES, Brazil Luiz Fernando De Ros 3Instituto de Geociências, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil e-mail: ronaldo.herlinger@petrobras.com.br Publisher: SEPM Society for Sedimentary Geology First Online: 12 Dec 2017 Online Issn: 1938-3681 Print Issn: 1527-1404 Copyright © 2017, SEPM (Society for Sedimentary Geology) Journal of Sedimentary Research (2017) 87 (12): 1285–1313. https://doi.org/10.2110/jsr.2017.70 Article history First Online: 12 Dec 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation Ronaldo Herlinger, Eveline Ellen Zambonato, Luiz Fernando De Ros; Influence of Diagenesis On the Quality of Lower Cretaceous Pre-salt Lacustrine Carbonate Reservoirs from Northern Campos Basin, Offshore Brazil. Journal of Sedimentary Research 2017;; 87 (12): 1285–1313. doi: https://doi.org/10.2110/jsr.2017.70 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyJournal of Sedimentary Research Search Advanced Search Abstract The genesis and evolution of lacustrine pre-salt carbonate reservoirs, which contain giant hydrocarbon accumulations along the South Atlantic margins, has attracted major research interest. The huge extension and volume, and unusual textural and compositional features, are key elements for understanding the tectonic, structural, stratigraphic, and sedimentological generation and early evolution of the region, as well as potentially of other lacustrine carbonate systems. A systematic petrographic and petrophysical study has been performed on the Lower Cretaceous lacustrine carbonate reservoirs from northern Campos Basin, Offshore Brazil, in order to unravel the main controls on the origin and evolution of pore systems. The main lithologic types recognized in the rift section are bivalve–gastropod grainstones and rudstones, arenites constituted by ooids of syngenetic magnesian clay minerals (mostly stevensite), and dolostones, while stevensitic claystones with calcite spherulites, fascicular calcite crusts, intraclastic rudstones and grainstones, and dolostones are the main lithologic types in the sag section. The eogenetic evolution of bioclastic reservoirs was controlled by the balance between dissolution and neomorphism of the aragonitic bivalve and gastropod bioclasts, favoring either the generation of poorly connected moldic porosity or the preservation of well-connected interparticle porosity. The stevensitic arenites were strongly affected by meteoric dissolution and replacement by dolomite and silica, related to regional uplift and erosion after the rift phase, which generated highly heterogeneous pore systems with moldic, intercrystalline, vugular, and microcrystalline pores. Stevensitic claystones that are replaced by calcite spherulites and dolomite normally show low porosity, but locally constitute reservoirs, where secondary porosity was generated by stevensite dissolution. The precipitation of crystal shrubs of fascicular-optic calcite in coalescent crusts generated growth-framework primary porosity, which was reduced mostly by dolomite cementation, or enlarged by dissolution, enhancing their permeability. Non-coalescent calcite crusts contain abundant syngenetic magnesian clay minerals. Their porosity is related to dissolution of these clays, which generated poor permeability. Intraclastic grainstones and rudstones are compacted and cemented, or rich in clay matrix ("hybrid packstones"). Where they display preserved interparticle primary porosity or matrix dissolution, they may have good porosity and permeability. The heterogeneous dolomitization of both the rift and the sag deposits either destroyed their primary or early diagenetic porosity, or generated high porosity and permeability values in the dolostones. Relationships between replacement and compaction indicate that most of the diagenetic processes occurred during eodiagenesis, controlled mostly by the instability of the aragonite in the bioclastic reservoirs and of the stevensite in the claystones, ooidal arenites, and fascicular calcite crusts. This study characterizes the major primary and diagenetic aspects of the pre-salt reservoirs, providing insights on the evolution of their porosity and permeability. This is expected to contribute to the prediction of quality during exploration and to enhance hydrocarbon recovery from producing oilfields, as well as to increase the understanding of the origin, evolution, and quality distribution in analogous lacustrine reservoirs. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.