Petrologia Sedimentar e Sedimentologia

Pretende-se nesta disciplina disponibilizar aos estudantes conhecimentos básicos que lhes permitam:

- interpretar os depósitos sedimentares e a sua relação com os processos que os originaram;
- planificar e executar uma análise de facies/análise sequencial;
- identificar ambientes de sedimentação;
- caracterizar os modelos sedimentares;
- conhecer e interpretar a génese e a evolução das bacias sedimentares;
- identificar os aspectos económicos ligados aos diferentes tipos de bacias sedimentares;
- utilizar os diferentes métodos aplicados ao estudo de bacias sedimentares.

The goals of the Sedimentary Petrology and Sedimentology are to provide students with the bases for interpreting sedimentary deposits in terms of processes, environments of deposition, sedimentary models, vertical successions of strata, and sedimentary basin fill.

With these goals in mind, we discuss the origin of sediments, the petrographic study and genetic interpretation of sedimentary rocks, the sedimentary models (showing in particular how it may be applied in the economic aspects), and sedimentary basins analysis.

I. Origem dos sedimentos
1) Alteração, transporte e deposição. 
2) Tipos de sedimentos. 
II. Rochas sedimentares
1) Diagénese: fases e processos.  
2) Classificação das rochas sedimentares.
3) Rochas sedimentares clásticas: tipos, propriedades e transformações diagenéticas.
4) Rochas sedimentares de precipitação química e bioquímica: tipos, propriedades e transformações diagenéticas dos minerais carbonatados.
5) Rochas sedimentares orgânicas. Carvões e hidrocarbonetos: genese, classificação, propriedades e transformações diagenéticas da matéria orgânica.

III. Ambientes de sedimentação
1) Conceito e classificação.
2)Fácies sedimentares: conceito. Análise sequêncial.

IV. Modelos de sedimentação

1) Modelo glaciar/periglaciar: génese e fácies. 2) Modelo desértico/eólico: depósitos, fácies e aspectos económicos. 3) Modelos fluviais:tipos de canais e de depósitos,facies e aspectos económicos). Cones aluviais: génese, unidades, fácies e aspectos económicos).
4) Modelos lacustres: conceito, classificação segundo Visher''''''''s (1965) e Kukal''''''''s (1971), fácies, e aspectos económicos). 5) Modelo deltáico:conceito, nomenclatura utilizada, unidades morfológicas, classificação triângular (processos dominantes),fácies, e aspectos económicos. 6) Modelos de plataformas: tipos,  processos dominantes, fácies e aspectos económicos. 7) Modelos de leques submarinos: génese, fácies e aspectos económicos. 8) Modelos pelágicos: fácies e aspectos económicos.

V. Bacias sedimentares
1) Conceito, génese e preenchimento.
2) Alguns exemplos de bacias sedimentares.
3) Métodos aplicados ao estudo e à análise de bacias sedimentares: sondagens, diagrafias e métodos geofísicos.

 I. Origin of sediments

Weathering types, transporte processes and deposition.

• Sediments types and economic significance of weathering.
• Deposition of sediments. Formation of pre-depositional, syndepositional and post-depositional sedimentary structures. Miscellaneous structures. Biogenic sedimentary structures.

II. Sedimentary rocks

• Diagenesis: stages and diagenetic processes. Factors that influence diagenesis.
• The classification of sedimentary rocks.
• Clastic sedimentary rocks: classification, and description of the four basic classes. Diagenesis evolution of sandstones, and clays and clay diagenesis.
• Chemical sedimentary rocks.
• Evaporites: evaporites minerals, and basin models for evaporites genesis.
• Phophates: phosphate minerals and basin models for phosphate formation.
• Carbonate: carbonate minerals, nomenclature and classification. Diagenesis and porosity evolution. Dolomite: mineralogical composition and basin models of dolomitization.
• Coals: main maceral groups of coal deposits, environments of coal deposition.
• Hydrocarbons: main stages in the development of hydrocarbons, types of hydrocarbon traps.
• Sedimentary iron ores: mineralogy and age of the principal sedimentary iron ores. Environments of deposition of iron ores.

III. Sedimentary environments

•  Environments: concept and classification of the sedimentary environments.
• Sedimentary models.
•  Fluvial systems: meandering river facies model, sand braided stream model, and the anastomosed model. Vertical fluvial sedimentary sequences.  Alluvial fans model and facies in humid and arid  regions; economic aspects of alluvial deposits.
• Lacustrine sedimentary models. Description of open freshwater model, closed perennial saline model, and hidrologically ephemeral salt pan model. Economic aspects of lake deposits. 
• Deltaic sedimentary models. Classification of deltas based on the dominant processes, and the nomenclature of a delta profile. Description of a wave-dominated deltas model, tide-dominated deltas model ,and river-dominated deltas model. Vertical deltaic sedimentary sequences. Economic aspects of deltaic deposits.
• Continental shelf systems and facies.
• Carbonate shelf system and reefs. Subtropical carbonate shelf classification. Rimmed shelves and open shelves models. The vertical shelves sequences. Reefs: zonation and facies of an organic modern reef. The main facies of allochthonous and autochthonous reef limestones. The organic reef sedimentary model. Economic aspects of carbonates and reefs.
• Deep sea system and facies.
• Terrigenous deep sea sands: sedimentary models of terrigenous deep sea sand deposits, and the vertical sequences of these deposits. Economic aspects of deep sea sands.
•  Pelagic sediments: classification and distribution of the pelagic deposits. The pelagic sediments model, and economic aspects of pelagic deposits.

IV. The sedimentary basin-fill

• Sedimentary basins: concepts and classifications.
• Some examples of the sedimentary basins.

ALLEN, P. A. & ALLEN, J. R. (1993) - Basin Analysis. Principles and Applications. Blackwell Scientific Publications, Oxford, 451pp.

COJAN, I. & RENARD M. (1997) - Sédimentologie. Masson, Paris, 418pp.

EINSELE, G. , RICKEN, W. & SEILACHER, A. (1991) - Cycles and events in stratigraphy. Spring-Verlag, Berlin, 955pp.

 HUNT, R. E. (2006) - Characteristics of geologic materials and formations. A field guide for geotechnical engineers. CRC Press, London, 387pp.

MIALL, A. D. (1990) - Principles of sedimentary basin analysis. Spring-Verlag, Berlin, 667pp.

 READING, H. C. (1996) - Sedimentology: Process and Product. George Allen and Unwin, London, 344pp.

SELLEY, R. C. (1988) - Applied sedimentology. Academic Press, London, 446pp.

WALKER, R. G. & JAMES, N. P. (1992) - Facies models. Reponse to sea level change. Geological Association of Canada, Canada, 409pp.

 ALLEN, P. A. & ALLEN, J. R. (1993) - Basin Analysis. Principles and Applications. Blackwell Scientific Publications, Oxford, 451pp.

COJAN, I. & RENARD M. (1997) - Sédimentologie. Masson, Paris, 418pp.

EINSELE, G. , RICKEN, W. & SEILACHER, A. (1991) - Cycles and events in stratigraphy. Spring-Verlag, Berlin, 955pp.

HUNT, R. E. (2006) - Characteristics of geologic materials and formations. A field guide for geotechnical engineers. CRC Press, London, 387pp

MIALL, A. D. (1990) - Principles of sedimentary basin analysis. Spring-Verlag, Berlin, 667pp.

READING, H. C. (1996) - Sedimentology: Process and Product. George Allen and Unwin, London, 344pp.

SELLEY, R. C. (1988) - Applied sedimentology. Academic Press, London, 446pp.

WALKER, R. G. & JAMES, N. P. (1992) - Facies models. Reponse to sea level change. Geological Association of Canada, Canada, 409pp

São realizadas aulas de carácter teórico-prático, em regime tutorial em sala de aulas com uso de produtos multimedia, figuras, gráficos  e esquemas. São realizadas saídas de campo para levantamento e informação geológica, referentes a vários tipos de depósitos e de ambientes.

• We use multimedia produts, figures, sketches, etc.
• We offer sample test questions;
• we made field trips in the different palaeogeographic deposits.The field trips will focus mainly on sedimentological aspects (depositional architecture, sequences boundaries, sedimentary environments, etc.).