The Austral Basin (or Magallanes Basin) in southern Argentina is situated in a highly active tectonic zone. The openings of the South Atlantic and the Drake Passage to the east and south, active subduction in the west, and the related rise of the Andes have massively influenced the evolution of this area. In order to better understand the impacts of these tectonic events on basin formation to its present-day structure we analyzed 2D seismic reflection data covering about 95.000 km² on-and 115.000 km² offshore (Austral "Marina"

Paleozoic and Mesozoic outcrop and core samples (REMINA Dekese and REMINA Samba wells) covering various stratigraphic intervals from the central Congo Basin were analyzed for total organic carbon (C org), total inorganic carbon (C inorg), and total sulfur content. Rock-Eval analysis and vitrinite reflectance (R o) measurements were performed on the basis of the C org content. Fifteen samples were chosen for molecular organic geochemistry. Nonaromatic hydrocarbons (HCs) were analyzed by gas chromatography (GC)-flame ionization detection and GC-mass spectrometry. Samples of the Alolo shales from the Aruwimi Group (Lindi Supergroup, late Neoproterozoic to early Paleozoic) are in general very poor in C org (most samples <0.5%) and contain a high amount of degraded organic matter (OM). All samples of this group revealed a type III to IV kerogen and cannot be considered as a potential source rock. Permian-Carboniferous sediments from the Lukuga Group (Dekese well and outcrop samples) contain moderate contents of organic carbon (<2%). The T max values (heating temperature at which the top peak of S 2 occurs) indicate early mature OM, partly also a higher level of maturity because of R o (0.6-0.7%) and production index values (S 1 /S 1 + S 2 < 0.2). All samples contain hydrogen-poor type III to IV kerogen with low HC generation potential, only having a very minor gas generation potential. The kinds of OM, as well as the biological markers, indicate a terrestrial-dominated depositional environment.

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A detailed 3D petroleum system model was constructed for the Schleswig-Holstein area in northern Germany. Salt movement and the Quaternary ice episodes were implemented in order to reconstruct their impact on temperature, maturity and pressure. Burial, temperature and maturity histories were calculated for the Jurassic troughs and the Glueckstadt Graben showing both differences and similarities. For example, all locations reached (almost) deepest burial at present day, whilst subsidence and long-term sedimentation rate was highest in Glueckstadt Graben during the Triassic. The Jurassic troughs received their major subsidence and sedimentation pulse later, and were strongly affected by a later salt movement.The implementation of Quaternary glacial episodes does not have a strong impact on petroleum generation from the major source rock (Lower Toarcian Posidonia Shale). In the case of the Posidonia Shale reaching the stage of petroleum expulsion (outside of the study area), the effect of ‘glacial pumping’( i.e. the development of high pore pressures during glaciation followed by expulsion and subsequent pressure release during deglaciation) can be deduced from the model. Petroleum accumulations in the reservoir layers (Dogger sandstones) are also seen to have been affected. This finding is of interest for exploration, as it might control petroleum composition, biodegradation and leakage through cap rocks.

Organic-rich silty marls and limestones (Pliensbachian to earliest Toarcian) exposed at Aït Moussa in Boulemane Province are the only known example of an effective petroleum source rock in the Middle Atlas of Morocco. In this study, petrological and organic-geochemical analyses (vitrinite reflectance measurements, Rock-Eval pyrolysis, GC-MS) were carried out in order to evaluate the maturity, quality and quantity of the organic matter (OM) and to investigate the depositional environment of these source rocks. Results indicate the presence of Type I/II kerogen which was deposited under marine conditions with an input of predominantly algal-derived organic matter. The presence of woody particles indicates minor input of terrestrial material. Organic-geochemical and biomarker analyses are consistent with deposition of carbonate-rich sediments under oxygendepleted but not anoxic conditions. In terms of thermal maturity, the sediments have reached the oil window (0.5-0.6 %VR r ) but not peak oil generation, although petroleum generation and migration are indicated by organic geochemical and microscopic evidence.Kinetic parameters derived from an investigation of petroleum generation characteristics show that the kerogen decomposes within a narrow temperature interval due to the fairly homogenous structure of the algal-derived organic matter. The kinetic parameters together with vitrinite reflectance data were used to construct a 1D model of the burial, thermal and maturation history of the Aït Moussa locality. The model suggested that deepest burial (approx. 3200 m) for the Pliensbachian succession took place in the Eocene (approx. 40 Ma). Two phases of hydrocarbon generation occurred, the first in the Late Jurassic/Early Cretaceous (approx. 150 Ma), and the second at the time of deepest burial (Eocene).

This study presents a 3D numerical model of a study area in the NW part of the Persian Gulf, offshore SW Iran. The purpose is to investigate the burial and thermal history of the region from the Cretaceous to the present day, and to investigate the location of hydrocarbon generating kitchens and the relative timing of hydrocarbon generation/migration versus trap formation. The study area covers about 20,000 km2 and incorporates part of the intra‐shelf Garau‐Gotnia Basin and the adjacent Surmeh‐Hith carbonate platform. A conceptual model was developed based on the interpretation of 2700 km of 2D seismic lines, and depth and thickness maps were created tied to data from 20 wells. The thermal model was calibrated using bottom‐hole temperature and vitrinite reflectance data from ten wells, taking into account the main phases of erosion/non‐deposition and the variable temporal and spatial heat flow histories. Estimates of eroded thicknesses and the determination of heat‐flow values were performed by burial and thermal history reconstruction at various well and pseudo‐well locations. Burial, temperature and maturation histories are presented for four of these locations. Detailed modelling results for Neocomian and Albian source rock successions are provided for six locations in the intra‐shelf basin and the adjacent carbonate platform. Changes in sediment supply and depocentre migration through time were analyzed based on isopach maps representing four stratigraphic intervals between the Tithonian and the Recent. Backstripping at various locations indicates variable tectonic subsidence and emergence at different time periods. The modelling results suggest that the convergence between the Eurasian and Arabian Plates which resulted in the Zagros orogeny has significantly influenced the burial and thermal evolution of the region. Burial depths are greatest in the study area in the Binak Trough and Northern Depression. These depocentres host the main kitchen areas for hydrocarbon generation, and the organic‐rich Neocomian and Albian source rock successions have been buried sufficiently deeply to be thermally mature. Early oil window maturities for these successions were reached between the Late Cretaceous (90 Ma) and the early Miocene (18 Ma) at different locations, and hydrocarbon generation may continue at the present‐day.