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Monitoring viscosity changes from time‐lapse seismic attenuation: case study from a heavy oil reservoir 下载免费PDF全文
Heating heavy oil reservoirs is a common method for reducing the high viscosity of heavy oil and thus increasing the recovery factor. Monitoring of these viscosity changes in the reservoir is essential for delineating the heated region and controlling production. In this study, we present an approach for estimating viscosity changes in a heavy oil reservoir. The approach consists of three steps: measuring seismic wave attenuation between reflections from above and below the reservoir, constructing time‐lapse Q and Q?1 factor maps, and interpreting these maps using Kelvin–Voigt and Maxwell viscoelastic models. We use a 4D relative spectrum method to measure changes in attenuation. The method is tested with synthetic seismic data that are noise free and data with additive Gaussian noise to show the robustness and the accuracy of the estimates of the Q‐factor. The results of the application of the method to a field data set exhibit alignment of high attenuation zones along the steam‐injection wells, and indicate that temperature dependent viscosity changes in the heavy oil reservoir can be explained by the Kelvin–Voigt model. 相似文献
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Kara-Bogaz-Gol Bay is a large (around 18,000 km2) and shallow (few meters deep) lagoon located east of the Caspian Sea. Its water surface was several meters to several dozens cm lower than in the Caspian Sea, so water flows from the Caspian Sea through a narrow strait into the bay, where it evaporates. Kara-Bogaz-Gol Bay is one of the saltiest bodies of water in the world; its water salinity amounts to 270–300 g/l. Different kinds of salts available in this natural evaporative basin has been used commercially since at least the 1920s. In March 1980, in order to decelerate a continuous fall of the Caspian Sea level, which in 1977 was the lowest over the last 400 years (?29 m), the Kara-Bogaz-Gol Strait was dammed. In response to this human intervention, the bay had already dried up completely by November 1983. In 1992, the dam was destroyed, and Kara-Bogaz-Gol Bay had been filling up with the Caspian Sea water at a rate of about 1.7 m/year up to 1996 as observed by the TOPEX/Poseidon satellite altimetry mission. Since then, Kara-Bogaz-Gol Bay level evolution with characteristic seasonal and interannual oscillations has been similar to that of the Caspian Sea. Physical and chemical evolution of the bay in the twentieth and twenty-first centuries is traced in detail in the paper. 相似文献
106.
Turbulent measurements in the stable atmospheric boundary layer during SHEBA: ten years after 总被引:4,自引:0,他引:4
Andrey A. Grachev Edgar L. Andreas Christopher W. Fairall Peter S. Guest P. Ola G. Persson 《Acta Geophysica》2008,56(1):142-166
This paper surveys results of the comprehensive turbulent measurements in the stable boundary layer (SBL) made over the Arctic
pack ice during the Surface Heat Budget of the Arctic Ocean experiment (SHEBA) in the Beaufort Gyre from October 1997 through
September 1998. Turbulent fluxes and mean meteorological data were continuously measured and reported hourly at five levels
on a 20-m main SHEBA tower. Eleven months of measurements during SHEBA cover a wide range of stability conditions, from the
weakly unstable regime to very stable stratification, and allow studying the SBL in detail.
A brief overview of the SBL regimes, the flux-profile relationships, the turbulent Prandtl number, and other parameters obtained
during SHEBA is given. The traditional Monin—Obukhov approach, z-less scaling, and gradient-based scaling are evaluated and discussed based on the data from SHEBA. 相似文献
107.
Andrey G. Andreev Maxim V. Budyansky Michael Yu. Uleysky Sergey V. Prants 《Ocean Dynamics》2018,68(11):1503-1514
Large canyons incise the shelf break of the eastern Bering Sea to be preferred sites of the cross-shelf exchange. The mesoscale eddy activity is particularly strong near the shelf-break canyons. To study the mesoscale dynamics in the Navarin Canyon area of the Bering Sea, the time series of velocities derived from AVISO satellite altimetry between 1993 and 2015, drifters, Argo buoys, and ship-borne data are analyzed. We demonstrate that the strength of anticyclonic eddies along the shelf edge in spring and summer is determined by the wind stress in March–April. The increased southward wind stress in the central Bering Sea forced a supply of low-temperature and low-salinity outer shelf water to the deep basin and formation of the anticyclonic mesoscale circulation seaward of the Navarin Canyon. Enhanced northwestward advection of the Bering Slope Current water leads to increase in an ice-free area in March and April and increased bottom-layer temperature at the outer shelf. The strong (weak) northwestward advection of the eastern Bering Sea waters, determined by eastern winds in spring, creates favorable (unfavorable) conditions for the pollock abundance in the western Navarin Canyon area in summer. 相似文献
108.
Andreev Andrey G. Budyansky Maxim V. Khen Gennady V. Uleysky Michael Yu. 《Ocean Dynamics》2020,70(5):593-602
Ocean Dynamics - To study the water dynamics in the western Bering Sea, the time series of geostrophic velocities derived from satellite altimetry, Global total current (Copernicus Globcurrent)... 相似文献
109.
Dell Sergius Abakumov Ivan Znak Pavel Gajewski Dirk Kashtan Boris Ponomarenko Andrey 《Studia Geophysica et Geodaetica》2019,63(4):538-553
Studia Geophysica et Geodaetica - Imaging of small-scale heterogeneities is important for the geological exploration in complex environments. It requires a processing sequence tuned to... 相似文献
110.
Mesoscale circulation along the Sakhalin Island eastern coast 总被引:1,自引:1,他引:0
Sergey V. Prants Andrey G. Andreev Michael Yu. Uleysky Maxim V. Budyansky 《Ocean Dynamics》2017,67(3-4):345-356
The seasonal and interannual variability of mesoscale circulation along the eastern coast of the Sakhalin Island in the Okhotsk Sea is investigated using the AVISO velocity field and oceanographic data for the period from 1993 to 2016. It is found that mesoscale cyclones with the horizontal dimension of about 100 km occur there predominantly during summer, whereas anticyclones occur predominantly during fall and winter. The cyclones are generated due to a coastal upwelling forced by northward winds and the positive wind stress curl along the Sakhalin coast. The anticyclones are formed due to an inflow of low-salinity Amur River waters from the Sakhalin Gulf intensified by southward winds and the negative wind stress curl in the cold season. The mesoscale cyclones support the high biological productivity at the eastern Sakhalin shelf in July– August. 相似文献