Clustering Analysis for Improved Characterization of Carbonate Reservoirs in a Southern Iraqi Oil Field

Carbonate reservoirs are highly heterogeneous. During waterflooding stage, the channeling phenomenon of displacing fluid in high-permeability layers easily leads to early water breakthrough and high water-cut with low recovery rate. To quantitatively characterize the inter-well connectivity parameters (including conductivity and connected volume), we developed an inter-well connectivity model based on the principle of inter-well connectivity and the geological data and development performance of carbonate reservoirs. Thus, the planar water injection allocation factors and water injection utilization rate of different layers can be obtained. In addition, when the proposed model is integrated with automatic history matching method and production optimization algorithm, the real-time oil and water production can be optimized and predicted. Field application demonstrates that adjusting injection parameters based on the model outputs results in a 1.5% increase in annual oil production, which offers significant guidance for the efficient development of similar oil reservoirs. In this study, the connectivity method was applied to multi-layer real reservoirs for the first time, and the injection and production volume of injection-production wells were repeatedly updated based on multiple iterations of water injection efficiency. The correctness of the method was verified by conceptual calculations and then applied to real reservoirs. So that the oil field can increase production in a short time, and has good application value.

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Genetic diversity of table grape based on morphoagronomic traits

Scientia Agricola ◽

10.1590/s0103-90162011000100007 ◽

2011 ◽

Vol 68 (1) ◽

pp. 42-49 ◽

Cited By ~ 14

Author(s):

Patrícia Coelho de Souza Leão ◽

Cosme Damião Cruz ◽

Sérgio Yoshimitsu Motoike

Keyword(s):

Genetic Diversity ◽

Clustering Analysis ◽

Germplasm Collection ◽

Table Grape ◽

Cluster Method ◽

Breeding Programs ◽

Method Analysis ◽

Vitis Spp ◽

Grape Cultivars

The conservation and characterization of grape (Vitis spp) genetic resources in germplasm banks have been the basis of its use in breeding programs that result in development of new cultivars. There are at least 10,000 grape cultivars kept in germplasm collection. The genetic diversity in 136 table grape accessions from the state of Bahia, Brazil, was evaluated. Continuous and discrete morphoagronomic traits were assessed. The clustering analysis by the Tocher otimization method resulted in 30 clusters (considering continuous morphoagronomic traits), and 9 clusters (taking into consideration multicategorical traits). There was no agreement between clusters obtained by both, continuous or discrete phenotypic descriptors, independent of the cluster method analysis used. A satisfactory genetic variability among the table grape accessions was observed.

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Geomechanical aspects of induced microseismicity during CO2 injection in Illinois Basin

The Leading Edge ◽

10.1190/tle40110823.1 ◽

2021 ◽

Vol 40 (11) ◽

pp. 823-830

Author(s):

Nikita Bondarenko ◽

Sherilyn Williams-Stroud ◽

Jared Freiburg ◽

Roman Makhnenko

Keyword(s):

Oil Field ◽

Co2 Injection ◽

Low Permeability ◽

Illinois Basin ◽

Petrographic Analysis ◽

Flow Properties ◽

Geomechanical Characterization ◽

Fluid Penetration ◽

Geophysical Log

Carbon sequestration activities are increasing in a global effort to mitigate the effects of greenhouse gas emissions on the climate. Injection of wastewater and oil-field fluids is known to induce seismic activity. This makes it important to understand how that risk relates to CO2 injection. Injection of supercritical CO2 into the Cambrian Mt. Simon sandstone in Illinois Basin induced microseismicity that was observed below the reservoir, primarily in the Precambrian crystalline basement. Geomechanical and flow properties of rock samples from the involved formations were measured in the laboratory and compared with geophysical log data and petrographic analysis. The controlling factors for induced microseismicity in the basement seem to be the hydraulic connection between the reservoir and basement rock and reactivation of pre-existing faults or fractures in the basement. Additionally, the presence of a laterally continuous low-permeability layer between reservoir and basement may have prevented downward migration of pore pressure and reactivation of critically stressed planes of weakness in the basement. Results of the geomechanical characterization of this intermediate layer indicate that it may act as an effective barrier for fluid penetration into the basement and that induced microseismicity is likely to be controlled by the pre-existing system of faults. This is because the intact material is not expected to fail under the reservoir stress conditions.

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Identifying Métiers Using Landings Profiles: An Octopus-Driven Multi-Gear Coastal Fleet

Journal of Marine Science and Engineering ◽

10.3390/jmse9091022 ◽

2021 ◽

Vol 9 (9) ◽

pp. 1022

Author(s):

Monika J. Szynaka ◽

Karim Erzini ◽

Jorge M. S. Gonçalves ◽

Aida Campos

Keyword(s):

Clustering Analysis ◽

Limited Data ◽

Target Species ◽

Fishing Gears ◽

Initial Characterization ◽

Management Advice ◽

South Portugal

The multi-gear coastal vessels in the Algarve (South Portugal) own licenses for various fishing gears. However, it is generally uncertain what gears they use, which is problematic as each individual gear is responsible for unique impacts on the resources and the environment. In this study, landing profiles identified for the multi-gear coastal fleet (2012–2016) were used as support in defining potential métiers using k-mean clustering analysis (CLARA) along with information from past studies on métiers. The results showed that more than 50% of the vessels were engaged in the octopus fishery year-round, using traps, while a small percentage (~13%) were entirely dedicated to clam dredging. In general, gillnets (21%) were used to target monkfish, hake and bastard soles, while trammel nets (6%) were used to target cuttlefish, with some vessels alternating the fishing gears (either seasonally or annually) according to target species. The method for the initial characterization of this fleet’s métiers and its efficiency with limited data is discussed, as well as the utility of this segmentation in support of management advice.

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