An integrated seismic-scale analysis of reservoir compartmentalisation on continental margins : the Espirito Santo Basin, SE Brazil

Deepwater continental margins constitute one of the ultimate exploration frontiers where giant oilfields have been discovered. These comprise reservoirs units affected by multi‐scale compartmentalisation resultant from stratigraphic, structural and/or diagenetic processes that compromise the lateral and/or vertical connectivity of permeable strata. A 3D seismic dataset from the deepwater Espírito Santo Basin (SE Brazil) was analysed to assess and quantify the architectural elements that influence the compartmentalisation of reservoir units. Mass‐Transport Deposits (MTDs) have growing importance on reservoir studies as they highly impact the compartmentalisation of contemporaneous reservoir‐prone turbidite strata. More significant compartmentalisation occurs in areas with higher MTD proportion, which are associated to wider dimensional ranges of laterally limited turbidites. However, salt diapirs constitute important barriers for MTD erosion, thus aiding the preservation of reservoir‐prone turbidites. The internal compositional heterogeneities and cohese strata on remnant and rafted blocks identified within the studied MTDs constitute important fluid flow or accumulation compartments, particularly when linked to underlying permeable faults. Submarine channels in Palaeocene and Neogene Units comprise important reservoir‐prone strata, thus it is crucial to understand their spatial distribution. Large channels are focused along the axis of salt‐withdrawal basins, whereas in sub‐units with numerous smaller channels these are laterally scattered across the basin. A new quantitative method used in this study shows that channel confluences and topographic confinement control significantly the density and spatial distribution patterns of submarine channels. A novel classification for submarine channel confluences is proposed, based on channel morphology and distribution of sediment facies within the tributaries. The key aim of this thesis was to undertake a seismic‐scale qualitative and quantitative analysis of the compartmentalisation of reservoir units on the Brazilian margin using methodologies that can be applied to other continental margins worldwide. As such, the results of this study can provide significant contributions for hydrocarbon exploration.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

An integrated seismic-scale analysis of reservoir compartmentalisation on continental margins: the Espirito Santo Basin, SE Brazil

Deepwater continental margins constitute one of the ultimate exploration frontiers where giant oilfields have been discovered. These comprise reservoirs units affected by multi‐scale compartmentalisation resultant from stratigraphic, structural and/or diagenetic processes that compromise the lateral and/or vertical connectivity of permeable strata. A 3D seismic dataset from the deepwater Espírito Santo Basin (SE Brazil) was analysed to assess and quantify the architectural elements that influence the compartmentalisation of reservoir units. Mass‐Transport Deposits (MTDs) have growing importance on reservoir studies as they highly impact the compartmentalisation of contemporaneous reservoir‐prone turbidite strata. More significant compartmentalisation occurs in areas with higher MTD proportion, which are associated to wider dimensional ranges of laterally limited turbidites. However, salt diapirs constitute important barriers for MTD erosion, thus aiding the preservation of reservoir‐prone turbidites. The internal compositional heterogeneities and cohese strata on remnant and rafted blocks identified within the studied MTDs constitute important fluid flow or accumulation compartments, particularly when linked to underlying permeable faults. Submarine channels in Palaeocene and Neogene Units comprise important reservoir‐prone strata, thus it is crucial to understand their spatial distribution. Large channels are focused along the axis of salt‐withdrawal basins, whereas in sub‐units with numerous smaller channels these are laterally scattered across the basin. A new quantitative method used in this study shows that channel confluences and topographic confinement control significantly the density and spatial distribution patterns of submarine channels. A novel classification for submarine channel confluences is proposed, based on channel morphology and distribution of sediment facies within the tributaries. The key aim of this thesis was to undertake a seismic‐scale qualitative and quantitative analysis of the compartmentalisation of reservoir units on the Brazilian margin using methodologies that can be applied to other continental margins worldwide. As such, the results of this study can provide significant contributions for hydrocarbon exploration

Combinations of single-top-quark production cross-section measurements and vertical bar f(LV)V(tb)vertical bar determinations at root s=7 and 8 TeV with the ATLAS and CMS experiments

This paper presents the combinations of single-top-quark production cross-section measurements by the ATLAS and CMS Collaborations, using data from LHC proton-proton collisions at = 7 and 8 TeV corresponding to integrated luminosities of 1.17 to 5.1 fb(-1) at = 7 TeV and 12.2 to 20.3 fb(-1) at = 8 TeV. These combinations are performed per centre-of-mass energy and for each production mode: t-channel, tW, and s-channel. The combined t-channel cross-sections are 67.5 +/- 5.7 pb and 87.7 +/- 5.8 pb at = 7 and 8 TeV respectively. The combined tW cross-sections are 16.3 +/- 4.1 pb and 23.1 +/- 3.6 pb at = 7 and 8 TeV respectively. For the s-channel cross-section, the combination yields 4.9 +/- 1.4 pb at = 8 TeV. The square of the magnitude of the CKM matrix element V-tb multiplied by a form factor f(LV) is determined for each production mode and centre-of-mass energy, using the ratio of the measured cross-section to its theoretical prediction. It is assumed that the top-quark-related CKM matrix elements obey the relation |V-td|, |V-ts| << |V-tb|. All the |f(LV)V(tb)|(2) determinations, extracted from individual ratios at = 7 and 8 TeV, are combined, resulting in |f(LV)V(tb)| = 1.02 +/- 0.04 (meas.) +/- 0.02 (theo.). All combined measurements are consistent with their corresponding Standard Model predictions.Peer reviewe

New insights into the genetic etiology of Alzheimer’s disease and related dementias

Characterization of the genetic landscape of Alzheimer’s disease (AD) and related dementias (ADD) provides a unique opportunity for a better understanding of the associated pathophysiological processes. We performed a two-stage genome-wide association study totaling 111,326 clinically diagnosed/‘proxy’ AD cases and 677,663 controls. We found 75 risk loci, of which 42 were new at the time of analysis. Pathway enrichment analyses confirmed the involvement of amyloid/tau pathways and highlighted microglia implication. Gene prioritization in the new loci identified 31 genes that were suggestive of new genetically associated processes, including the tumor necrosis factor alpha pathway through the linear ubiquitin chain assembly complex. We also built a new genetic risk score associated with the risk of future AD/dementia or progression from mild cognitive impairment to AD/dementia. The improvement in prediction led to a 1.6- to 1.9-fold increase in AD risk from the lowest to the highest decile, in addition to effects of age and the APOE ε4 allele