3ERL - Courses and Lectures/ Cursos e Lições
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- Atlas of typical deep water seismic linesPublication . Cramez, CarlosIn this atlas, commented tentative geological interpretations, mainly, of Canvas autotraces of worldwide typical deep water seismic lines are proposed. The Bally and Snelson’s (1980) sedimentary basin classification was adopted. Remind: (i) Rift-Type basins, Cratonic basins and Atlantic-type Divergent Margins are sedimentary basins not associated with the formation of Megasutures ; (ii) Episutural and Perisutural basins are associated with the formation of Megasutures ; (iii) Forearcs, foredeeps and Chinese-type basins are perisutural bsins, the firsts associated with B-type subduction zones, the second with A-type subduction zones and the thirds with tilted blocks, normally developed by megasutures but, where the subduction zone A is not evident ; (iv) Backarcs and non Atlantic-type divergent margins are episutural basins associated with B-type subduction zones, the firsts without oceanization behind the volcanic arc, the seconds with oceanization ; (v) Panonnian-type and Mediterranean-type basins are episutural basins associated with A-Type subduction zones, the firsts without oceanization and the seconds when there is breakup and oceanization of the underlying fold belt ; (vi) The Great Basin and Californian-type basins are episutural associated with significant strike slip faulting ; (vii) Fold belts are developed inside the megasutures in connection with A or B-type subduction zones.
- Need for drug delivery systemsPublication . Silva, Ana Catarina
- Frequent errors in the geological interpretation of seismic linesPublication . Cramez, Carlos1) All geological observation are theory laden. 2) Geoscientists forget to use the geological context on tentative geological interpretations of the seismic lines, locating them in relation to geographic or administrative basins and not to sedimentary basins defined in a specific basin classification. 3) Using the classification of Bally & Snelson (1980), geoscientists know, in advance, what they must to look for on seismic lines, because it gives the geological context of the main geological events and critical hydrocarbon parameters. 4) An easy refutation test of a geological interpretation (cross-section or seismic line) is to look at the dip of the proposed fault planes, which, at scale 1:1, must dip according to the Anderson's theory of faulting. 5) Every time a geoscientist shows you a delta slope on a seismic line, there is a high probability that he is showing a continental slope. The large majority of delta slopes are under seismic resolution. 6) A delta height, rarely, exceeds 100 m. A delta slope height, rarely, exceeds, 250 m. The length of a delta slope can reach more than 100 km. In appropriated geological settings, delta slopes are just visible on seismic lines with an important vertical exaggeration. 7) Geoscientists forget, often, that a seismic line looks like a geological cross section, but its vertical scale is in time (t.w.t.) and not in meters. A lot of corrections must be take into account. 8) The geometrical relationships between seismic reflectors and seismic surfaces defined, by reflections terminations, have a geological meaning just in its original depositional position. 9) At the scale of a sedimentary basin, all chronostratigraphic depositional surfaces have, a geometry, more or less, sigmoidal, with subhorizontal sectors confined by seaward dipping sectors. 10) In sequential stratigraphy, an unconformity is an erosional surface induced by a significant relative sea level fall. In other branches of the Geology an unconformity can have other meanings. 11) Some geoscientists continue to forget in their models the long periods of calm where nothing happens. In most stratigraphic sections, the duration of the hiatus is, generally, greater than the total duration of real deposition of the preserved sediments. 12) Few geoscientists know the difference between absolute and relative sea level. In addition, generally, they do not have any idea how sea level changes are measured, but they use them to explain the cyclicity of sedimentary deposits. 13) "When the sea level rise, we get a transgression and when the sea level falls we have a regression" [sic] is a false statement. A sedimentary transgression does not exist in Geology. A set of increasingly smaller sedimentary regressions can be, eventually, interpreted as the consequence of marine ingressions (transgressions). 14) When interpreting, in geological terms, a seismic line, do not forget, that the amount of sediments must be kept, more or less, constant. 15) Seismic lines are bad copies of geological reality. Tentative geological interpretations of seismic lines are far from showing the geological reality: they have a time vertical scale and a lot of lateral velocity changes inducing a lot of pitfalls. 16) Potential marine source-rock, can be localize, in the field or on seismic lines. They lie along the interfaces between retrogradational and progradational intervals.17) An angular unconformity is just a tectonically enhanced cryptic unconformity, i.e., an erosional surfaces induced by a relative sea level fall. Hydrocarbons traps associated with angular unconformities are independent of the mapping of the unconformity. They are defined by the maps of the reservoir-rock, sealing-rock and hydrocarbon migration paths. 18) Structural traps are developed in shortened geological structures. They have their own closure (four way dips). Traps against faults do not exist. Few geoscientists know what is a morphological trap by juxtaposition. Hydrodynamic traps in the majority of the cases are, totally, forgotten. 19) The first step in a tentative geological interpretations of a seismic line is to decide if the sediments are shortened or lengthened. A bad decision leads, necessarily, to a wrong tentative interpretation, because the geoscientist will be looking for geological events that are not present on the seismic line. 20) Lithological predictions can just be made on tentative geological interpretations of seismic lines made at the highest hierarchical level, i.e., at the sequence-paracycle level, in which the different depositional systems tracts and depositional systems are recognized.
- Challenges to carbon capture and storage: a portuguese case-studyPublication . Oliveira, GiselaThis lecture addresses the main challenges associated to the design of a CCS project and its subsequent installation and operation focusing on the Portuguese mainland as a case study. The work targets national sedimentary basins and based on the existing literature screens these basins to found suitable geologic formation for the permanent and safe CO2 geological storage. Several geological formations were identified as potential CO2 reservoirs most of them situated offshore. The assessment of risks associated to the geological storage of CO2 are considered based on a qualitative methodology.
- Understanding sea level changesPublication . Cramez, CarlosThe dramatic sea level rise announced by the media and politicians, is, for the people, in general, the most known and dangerous consequence of climate change. However, talk about sea level changes without specifying the reference surface and in what the place of the Earth’s surface does not make sense. Measuring sea level is not easy. The tide gauge measurements are questionable. Altimetric measurements by satellites cover, only, the recent period and the interpretation of their results is not always consistent. In addition, as ww will see there are different types of sea level: (i) Absolute or Eustatic Sea Level ; (ii) Relative Sea Level ; (iii) Sea Surface Height. Saying that sea level will rise 4 cm (Al Gore in his book "An Inconvenient Truth" says: “6 meters”) until the end of the century without telling what sea level is taking into account is a lie by omission. On this subject, the opening remarks of President J. Chirac in the 6th conference of parties to Kyoto (Hague, November 2000): “Kyoto is the first component of an authentic global governance”, are highly significant. In this lecture, after a small introduction and a reminder of the basic conjectures, we will review the different sea level types, how we can measure them and with what precision, as well as, the main sea level changes drivers. Sea level and climate changes, implies a categorization. Taking into both the duration and magnitude of the sea level and climate drivers, Vigneau, J. P. (2005) in Climatologie textbook proposed the following hierarchization, which should always be taking into account when talking about climate or sea level changes : (i) Pulsations (4th order climate drivers), lasting a few years or a few decades and which are, perfectly, reversible (e.g., series of years of raining or drought) ; (ii) Oscillations, (3rd order) lasting from a few centuries to a few millennia, but are reversible (e.g., the Little Ice Age) ; (iii) Fluctuations, (2nd order) spreading out over tens, hundreds of thousands of years and have mark cyclic character (e.g., the evolution of the Quaternary) ; (iv) Mutations (1st order), lasted millions, tens or hundreds of millions of years that have a irreversible character (e.g., irreversible upheavals of the Earth’s surface).
- Stratigraphy sequential: definitions, illustrations of the terms and conceptsPublication . Cramez, CarlosThis glossary of Sequential Stratigraphy should not be considered as an attempt to normalize the terminology of Sequential Stratigraphy. The work presented here corresponds, simply, to a compilation of definitions and concepts dispersed in the most varied publications on Sequential Stratigraphy. It is intended, primarily, to serve the young geoscientists who have followed our short courses and workshops, since all the terms defined here were all used in these classes. For each term, presented: (i) a succinct definition (with a translation in French, Portuguese, Spanish, German, Chinese, Russian and Italian which, later, will be updated, particularly the German translation) ; (ii) a tentative geological interpretaion of an auto-traces of a seismic line, a sketch or a photograph illustrating its meaning, and (iii) a commentary, sometimes with notes, clarifying certain points related to the illustration of the term.
- Estratigrafia sequencial: definições e ilustrações dos termos e conceitosPublication . Cramez, Carlos; Lemos de Sousa, M. J.Os glossários, thesaurus, ou léxicos e os vocabulários são, geralmente, elaborados tendo em vistas dois objectivos diferentes, mas complementares na práctica. Eles são concebidos quer para aparecerem como um apêndice no fim de um trabalho de fundo ou de um curso temático, dando a significação e outros detalhes sobre as palavras chave e/ou expressões utilizadas nos textos de base, quer destinados a ser publicados, digamos de maneira autónoma. O trabalho aqui apresentado corresponde, simplesmente, a uma compilação de definições e conceitos dispersas nas mais variadas publicações sobre a Estratigrafia Sequencial. Ele é destinado, principalmente, a servir os jovens geocientistas que seguiram os nossos cursos e ateliers, uma vez que todos os termos definidos foram e são utilizados nessas classes. No vocabulário, para cada termo, apresenta-se: (i) uma definição sucinta (com uma tradução em inglês, francês, espanhol, alemão, chinês, russo e italiano que, mais tarde, será actualizada, particularmente, a tradução em alemão) ; (ii) uma tentativa de interpretação de uma linha sísmica, um esquema ou uma fotografia ilustrando o seu significado e (iii) um comentário, por vezes com notas, esclarecendo determinados pontos relacionados com a ilustração do termo.
- Glossário ilustrado de estratigrafia sequencial e termos associadosPublication . Cramez, Carlos; Lemos de Sousa, M. J.Este Glossário de Estratigrafia Sequencial deve apenas ser considerado como uma primeira tentativa de normalização da terminologia desta especialidade. O trabalho que agora se apresenta corresponde a uma compilação de definições e doutrinas dispersas nas mais variadas publicações destinadas a servir os nossos alunos. Assim, à semelhança do que fizemos para geocientistas de certos países, este vocabulário foi elaborado, unicamente, para ajudar os jovens geocientistas que participem nos nossos cursos e ateliers, uma vez que a grande maioria dos termos aqui definidos são os utilizados durante os cursos. No vocabulário apresenta-se uma definição sucinta de cada termo e, bem assim, a sua tradução em sete línguas (inglês, francês, espanhol, alemão, chinês, russo e italiano). Alguns dos termos estrangeiros são tentativas de tradução que, mais tarde, serão actualizados (isto é, particularmente, verdade para os termos alemães).
- Atlantic-Type Divergent MarginsPublication . Cramez, Carlos
- Role of subaerial volcanic rocks and mantle plumes in creation of South Atlantic margins: implications for salt tectonics and source rocksPublication . Jackson, M. P. A.; Cramez, Carlos; Fonck, Jean-Michel
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