I measured physico-chemical properties and phytoplankton in the small, shallow tropical reservoir of Oyun (Offa, Nigeria) between January 2002 and December 2003. I identified 25 phytoplankton genera in three sampling stations. Bacillariophyceae dominated (75.3%), followed by Chlorophyceae (12.2%), Cyanobacteria (11.1%) and Desmidiaceae (0.73%). The high amount of nutrients (e.g. nitrate, phosph...

Local and turnover patterns of fish diversity in the Itaipu Reservoir were evaluated and related to a longitudinal or river-dam gradient (composed of riverine, transitional, and lacustrine zones) and to transversal or upstream-downstream gradients of the tributaries (composed of lotic and lentic stretches of tributaries and reservoir shores). Thirteen stations were sampled quarterly during 2 ye...

thermal recovery involves well-known processes such as steam injection (cyclic steam stimulation, steam drive, and steam-assisted gravity drainage), in situ combustion, and a more recent technique that consists of heating the reservoir with electrical energy. when high frequency is used for heating, it is called electromagnetic (em) heating. the applications of em heating for heavy-oil reservoi...

We consider optimization of computational grids for petroleum reservoir flow simulations. In this context grid quality is determined by two independent error sources. On the one hand there is a loss of precision caused by upscaling of geological data from the fine geological grid to the coarser computational grid, and on the other hand there are numerical errors induced by a non-regular computa...

In the late stage of ultra-high water cut development, untabulated reservoir (not included in submitted reserve sheet) is considered an important part production sustainability X oilfield. According to coring well data 5 wells eastern district, associated with higher heterogeneity. Specifically, it develops not only conventional low and ultra-low permeability sands but also medium-high thicknes...

Accurate prediction of petroleum reservoir performance requires reliable models of the often complex reservoir heterogeneity. Geostatistical simulation techniques generate multiple realizations of the reservoir model, all equally likely to be drawn. Traditional to geostatistics, geological continuity is represented through the variogram. The variogram is limited in describing complex geological...

Reservoir models with many grid blocks suffer from long run time; it is hence important to deliberate a method to remedy this drawback. Usual upscaling methods are proved to fail to reproduce fine grid model behaviors in coarse grid models in well proximity. This is attributed to rapid pressure changes in the near-well region. Standard permeability upscaling methods are limited to systems with ...

In view of the remaining oil recovery situation and needs development tertiary technology, using mercury intrusion data, through statistical analysis relationship between microscopic pore structure parameters permeability, it is clear that there a good correlation permeability various parameters. It believed reservoir can comprehensively quantitatively characterize complexity reservoir. The hig...