Search results for "mesozoic"
showing 10 items of 84 documents
Characterization of a fractured basement reservoir using high-resolution 3D seismic and logging datasets: A case study of the Sab'atayn Basin, Yemen.
2018
The Sab'atayn Basin is one of the most prolific Mesozoic hydrocarbon basins located in central Yemen. It has many oil producing fields including the Habban Field with oil occurrences in fractured basement rocks. A comprehensive seismic analysis of fractured basement reservoirs was performed to identify the structural pattern and mechanism of hydrocarbon entrapment and reservoir characteristics. A 3D post-stack time migration seismic cube and logging data of 20 wells were used and several 2D seismic sections were constructed and interpreted. Depth structure maps were generated for the basement reservoir and overlying formations. The top of the basement reservoir is dissected by a set of NW-S…
Sur la structure, l'âge et l'origine des « brèches de Bosmendiette » (Pyrénées-Atlantiques)
2004
Resume Anterieurement attribuees a l'Albo-Aptien et considerees comme resultant du diapirisme des evaporites triasiques, les breches de Bosmendiette se seraient, pour certains auteurs recents, mises en place au Selandien (Paleocene), dans des canyons sous-marins etablis au sein d'un profond sillon, le long de la chaine des Pyrenees, du Roussillon jusqu'a l'Atlantique. Leur âge serait fonde sur la decouverte d'une riche microfaune pelagique de globigerinides. Nos recherches montrent qu'azoiques a leur base, pourvues de radiolaires et de rares foraminiferes benthiques au sommet, ces breches resultent en realite de la destruction de boucles de slumps affectant l'« Infralias ». Recouvertes en o…
1999
The tholeiitic dolerites that crop out in three diapirs of the SE of the Iberian Chain (Alfarp, Quesa and Lugar Nuevo de Fenollet, Valencia), are the expression of evolved (low Ni, Cr and mg* values) basic magmas, injected into poorly lithified sediments (lutites, marls and gypsum) which represent the Upper Triassic (Keuper facies)-Hettangian boundary, developing sills with reduced thickness. Their mineral and whole-rock geochemical compositions indicate a continental tholeiitic affinity and certain similarities to a MORB composition and, on the other hand, show that the Alfarp dolerites represent the less evolved compositions, whereas the Fenollet dolerites show a significantly greater dif…
The Argille Varicolori Unit of Lucania (Italy): a record offscraping and gravity sliding in the Mesozoic-Tertiary Lagonegro Basin, southern Apennines
2006
Detailed geological mapping and new stratigraphic and structural data collected in the Lucania area of the southern Apennines allowed us to assess the deformation history of 11 Monte-Corleto Perticara zone, in the High Agri Valley (Lucanian Apennines, southern Italy) where red and green shales (known as Argille Varicolori or Argille scagliose) crop out. Our observations suggest that: (1) 'chaotic' facies within the Argille Varicolori may be attributed to a broken formation generated by overthrusting of Apenninic Platform units onto already deformed Lagonegro basin strata; (2) gravity sliding phenomena at the thrust front enhanced the development of debris flow and the emplacement of olistos…
Resumen cronoestratigráfico de las rocas ígneas de Costa Rica basado en dataciones radiométricas
1992
Resume El presente trabajo recopila los resultados de aproximadamente 160 dataciones radiometricas K-Ar y U-Th que se han realizado en Costa Rica en los ultimos 20 anos. Con base en estas dataciones y en relaciones estratigraficas se establecio un cuadro cronoestratigrafico sobre la evolucion del magmatismo desde el Mesozoico hasta el presente. Las rocas igneas del Jurasico hasta el Oligoceno se caracterizan por su tendencia toleitica. A partir del Mioceno tardio predominan rocas de la serie calcoalcalina y la actividad volcanica culmina en el Pleistoceno con la erupcion de grandes volumenes de ignimbritas en la parte norte y central de Costa Rica y la edificacion de los estratovolcanes de …
L'évolution paléoenvironnementale des faunes de poissons du Crétacé supérieur du bassin du Tafilalt et des régions avoisinantes (Sud-Est du Maroc) : …
2001
Abstract A critical revision of published data along with new field data allow to draw up the succession of the fish faunas from the Lower Cenomanian to the Lower Turonian in the Tafilalt basin and surrounding areas (southeast Morocco). The analysis of these faunas shows changes from freshwater to marine palaeoenvironments. The palaeogeographic distribution of some taxa is discussed. It shows that the crossing of strictly freshwater organisms between Africa and South America was likely impossible at the time of the formation of the deposits resting around the Tafilalt basin and named ‘Kem Kem beds’. The Cenomano-Turonian transgression reached the Erfoud–Errachidia carbonate platform from th…
Polyphased mesozoic rifting from the Atlas to the north-west Africa paleomargin
2021
24 pages; International audience; Based on the interpretation of geological maps, seismic reflection and well data complemented with a bibliographic compilation and field work in the Rif, we investigate the factors that control the rift initiation, its development and the formation of oceanic crust in NW Africa. From SE to NW, we examine the Western Sahara Atlas, the Tendrara, the Guercif, and the Rif basins, to establish their geodynamic evolution in relation with the Mesozoic formation of the Central Atlantic and Maghrebian Tethys oceans, respectively. The Triassic extension was diffuse and developed over Lower Carboniferous horst-and-graben structures formed in the NW passive margin of G…
Middle Triassic carbonate platforms in eastern Iberia: Evolution of their fauna and palaeogeographic significance in the western Tethys
2015
Abstract This article reports the first integrated study of the Middle Triassic of Iberia, based on the stratigraphy, sedimentology, and fossil fauna of Muschelkalk facies of the Iberian Ranges and the Catalan Coastal Ranges in Spain. On the basis of this study, new palaeogeographic reconstructions of the westernmost Tethys are proposed, and the evolution of the different palaeogeographic domains of Iberia (e.g., Iberian, Mediterranean, and Levantine–Balearic) are described. In these domains, Muschelkalk facies record the development of wide carbonate platforms that were the consequence of the first two broad marine transgressions of the Mesozoic in Iberia, respectively, late Pelsonian–earl…