Flow Units (flow + unit)

Distribution by Scientific Domains


Selected Abstracts


A FUZZY LOGIC APPROACH TO ESTIMATING HYDRAULIC FLOW UNITS FROM WELL LOG DATA: A CASE STUDY FROM THE AHWAZ OILFIELD, SOUTH IRAN

JOURNAL OF PETROLEUM GEOLOGY, Issue 1 2009
A. Kadkhodaie-Ilkhchi
Porosity-permeability relationships in the framework of hydraulic flow units can be used to characterize heterogeneous reservoir rocks. Porosity is a volumetric parameter whereas permeability is a measure of a rock's flow properties and depends on pore distribution and connectivity. Thus zonation of a reservoir using flow zone indicators and the identification of flow units can be used to evaluate reservoir quality based on porosity-permeability relationships. In the present study, we attempt to make a quantitative correlation between flow units and well log responses using fuzzy logic in the mixed carbonate-clastic Asmari Formation at the Ahwaz oilfield, South Iran. A hybrid neuro-fuzzy approach was used to verify the results of fuzzy modelling. For this purpose, well log and core data from three wells at Ahwaz were used to make an intelligent formulation between core-derived flow units and well log responses. Data from a separate well was used for evaluation and validation of the results. The results of this study demonstrate that there is a good agreement between core-derived and fuzzy-logic derived flow units. Fuzzy logic was successful in modelling flow units from well logs at well locations for which no core data was available. [source]


MAPPING AND CLASSIFYING FLOW UNITS IN THE UPPER PART OF THE MID-CRETACEOUS SARVAK FORMATION (WESTERN DEZFUL EMBAYMENT, SW IRAN) BASED ON A DETEMINATION OF RESERVOIR ROCK TYPES

JOURNAL OF PETROLEUM GEOLOGY, Issue 4 2007
B. Beiranvand
The mid-Cretaceous Sarvak Formation, the second-most important reservoir unit in Iran, is composed mainly of grain-supported carbonates. For the purposes of this study, flow units in the upper part of the formation were identified, mapped and classified as part of an integrated reservoir characterization study at a giant oilfield in SW Iran. Pore types and geometries, pore-scale diagenetic history and core-scale depositional attributes were logged using conventional petrographic and lithological methods. The resulting data were combined with core descriptions, mercury-injection capillary pressure data, and wireline log and geophysical data to identify five reservoir rock types: (i) highly oil-stained, grain-supported carbonates, including patch reef and barrier complex deposits with high porosities and permeabilities; (ii) leeward and seaward shoal deposits including grain-supported packstones and skeletal wackestones with high porosities and permeabilities; (iii) dominantly mud-supported lagoonal and open-marine facies with fair porosity and permeability; (iv) grain-supported but highly cemented facies which had poor reservoir characteristics; and (v) calcareous shales and shaly limestones with no reservoir quality. Based on the reservoir rock types, eight flow units were recognised. Subsequently, four reservoir zones were defined based on these flow units at a field scale. This study has contributed to our understanding of flow units in this complex carbonate reservoir, and has improved our ability to characterize and model the architecture of the reservoir from pore to core to field scale. [source]


An implicit velocity decoupling procedure for the incompressible Navier,Stokes equations

INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN FLUIDS, Issue 2 2002
Kyoungyoun Kim
Abstract An efficient numerical method to solve the unsteady incompressible Navier,Stokes equations is developed. A fully implicit time advancement is employed to avoid the Courant,Friedrichs,Lewy restriction, where the Crank,Nicolson discretization is used for both the diffusion and convection terms. Based on a block LU decomposition, velocity,pressure decoupling is achieved in conjunction with the approximate factorization. The main emphasis is placed on the additional decoupling of the intermediate velocity components with only nth time step velocity. The temporal second-order accuracy is preserved with the approximate factorization without any modification of boundary conditions. Since the decoupled momentum equations are solved without iteration, the computational time is reduced significantly. The present decoupling method is validated by solving several test cases, in particular, the turbulent minimal channel flow unit. Copyright © 2002 John Wiley & Sons, Ltd. [source]


Stratigraphy and volcanology of the Türkbükü volcanics: products of a stratovolcano in the Bodrum Peninsula, SW Anatolia

GEOLOGICAL JOURNAL, Issue 2 2006
Zekiye Karacik
Abstract The Middle-Upper Miocene Bodrum magmatic complex of the Aegean region, southwestern Turkey, is mainly represented by intermediate stocks, lavas, pyroclastic and volcaniclastic deposits. Monzonitic stocks and connected porphyry intrusions and extrusions are the first products of the magmatism. These are followed by a volcanic succession consisting of andesitic-latitic lavas, autobrecciated lavas, pyroclastic and volcaniclastic deposits. The final stage is represented by basaltic and basaltic andesitic flows and dykes intruded into previous units. The volcanic succession crops out in the northern part of the Bodrum peninsula. In the lower part of this succession are widespread pyroclastic deposits, composed of pyroclastic fall and flow units, alternating with epiclastic deposits. Grain size, volume and thickness of the pyroclastic deposits were mainly controlled by the type, magnitude and intensity of the eruption. Further up the section, there are two horizons of debris avalanche deposits forming the coarsest and thickest deposits of the volcaniclastic succession. The debris avalanche deposits indicate at least two different flank collapses coeval with the volcanism. The stratigraphy and map pattern of these volcanic units imply that the northern part of the Bodrum peninsula was the north-facing flank of a stratovolcano during the mid-Late Miocene. Copyright © 2006 John Wiley & Sons, Ltd. [source]


3D imaging of a reservoir analogue in point bar deposits in the Ferron Sandstone, Utah, using ground-penetrating radar

GEOPHYSICAL PROSPECTING, Issue 3 2004
Xiaoxian Zeng
ABSTRACT Most existing reservoir models are based on 2D outcrop studies; 3D aspects are inferred from correlation between wells, and so are inadequately constrained for reservoir simulations. To overcome these deficiencies, we have initiated a multidimensional characterization of reservoir analogues in the Cretaceous Ferron Sandstone in Utah. Detailed sedimentary facies maps of cliff faces define the geometry and distribution of reservoir flow units, barriers and baffles at the outcrop. High-resolution 2D and 3D ground-penetrating radar (GPR) images extend these reservoir characteristics into 3D to allow the development of realistic 3D reservoir models. Models use geometric information from mapping and the GPR data, combined with petrophysical data from surface and cliff-face outcrops, and laboratory analyses of outcrop and core samples. The site of the field work is Corbula Gulch, on the western flank of the San Rafael Swell, in east-central Utah. The outcrop consists of an 8,17 m thick sandstone body which contains various sedimentary structures, such as cross-bedding, inclined stratification and erosional surfaces, which range in scale from less than a metre to hundreds of metres. 3D depth migration of the common-offset GPR data produces data volumes within which the inclined surfaces and erosional surfaces are visible. Correlation between fluid permeability, clay content, instantaneous frequency and instantaneous amplitude of the GPR data provides estimates of the 3D distribution of fluid permeability and clay content. [source]


A FUZZY LOGIC APPROACH TO ESTIMATING HYDRAULIC FLOW UNITS FROM WELL LOG DATA: A CASE STUDY FROM THE AHWAZ OILFIELD, SOUTH IRAN

JOURNAL OF PETROLEUM GEOLOGY, Issue 1 2009
A. Kadkhodaie-Ilkhchi
Porosity-permeability relationships in the framework of hydraulic flow units can be used to characterize heterogeneous reservoir rocks. Porosity is a volumetric parameter whereas permeability is a measure of a rock's flow properties and depends on pore distribution and connectivity. Thus zonation of a reservoir using flow zone indicators and the identification of flow units can be used to evaluate reservoir quality based on porosity-permeability relationships. In the present study, we attempt to make a quantitative correlation between flow units and well log responses using fuzzy logic in the mixed carbonate-clastic Asmari Formation at the Ahwaz oilfield, South Iran. A hybrid neuro-fuzzy approach was used to verify the results of fuzzy modelling. For this purpose, well log and core data from three wells at Ahwaz were used to make an intelligent formulation between core-derived flow units and well log responses. Data from a separate well was used for evaluation and validation of the results. The results of this study demonstrate that there is a good agreement between core-derived and fuzzy-logic derived flow units. Fuzzy logic was successful in modelling flow units from well logs at well locations for which no core data was available. [source]


MAPPING AND CLASSIFYING FLOW UNITS IN THE UPPER PART OF THE MID-CRETACEOUS SARVAK FORMATION (WESTERN DEZFUL EMBAYMENT, SW IRAN) BASED ON A DETEMINATION OF RESERVOIR ROCK TYPES

JOURNAL OF PETROLEUM GEOLOGY, Issue 4 2007
B. Beiranvand
The mid-Cretaceous Sarvak Formation, the second-most important reservoir unit in Iran, is composed mainly of grain-supported carbonates. For the purposes of this study, flow units in the upper part of the formation were identified, mapped and classified as part of an integrated reservoir characterization study at a giant oilfield in SW Iran. Pore types and geometries, pore-scale diagenetic history and core-scale depositional attributes were logged using conventional petrographic and lithological methods. The resulting data were combined with core descriptions, mercury-injection capillary pressure data, and wireline log and geophysical data to identify five reservoir rock types: (i) highly oil-stained, grain-supported carbonates, including patch reef and barrier complex deposits with high porosities and permeabilities; (ii) leeward and seaward shoal deposits including grain-supported packstones and skeletal wackestones with high porosities and permeabilities; (iii) dominantly mud-supported lagoonal and open-marine facies with fair porosity and permeability; (iv) grain-supported but highly cemented facies which had poor reservoir characteristics; and (v) calcareous shales and shaly limestones with no reservoir quality. Based on the reservoir rock types, eight flow units were recognised. Subsequently, four reservoir zones were defined based on these flow units at a field scale. This study has contributed to our understanding of flow units in this complex carbonate reservoir, and has improved our ability to characterize and model the architecture of the reservoir from pore to core to field scale. [source]


The melting temperature (or not melting) of poly(vinyl chloride)

JOURNAL OF VINYL & ADDITIVE TECHNOLOGY, Issue 3 2008
James W. Summers
The best answer to what is the melting temperature of PVC is its previous processing temperature. That temperature is where secondary crystallites, created by gelation, melt and allow the primary particle flow units to flow again independently. In the case of powder compounds being processed for the first time, the question of melting is less relevant. The PVC, out of the polymerizer, contains crystallites that are not completely meltable. The issue is how easily the grains of PVC disperse to primary particle flow units. This property depends on polymerization conditions and the type of processing equipment. The temperature achieved affects the amount of fusion (gelation). J. VINYL ADDIT. TECHNOL., 2008. © 2008 Society of Plastics Engineers. [source]


Lubrication mechanism of poly(vinyl chloride) compounds: Changes upon PVC fusion (gelation)

JOURNAL OF VINYL & ADDITIVE TECHNOLOGY, Issue 2 2005
James W. Summers
Poly(vinyl chloride) (PVC) compounds perform best with adequate metal lubrication and polymer-to-polymer lubrication of PVC primary particle flow units. Much of the mechanism for the lubrication of PVC has been elucidated over the years. One point has not been completely understood, which is the "lubricant failure" at higher processing temperatures where the compound is known to become less ductile. This result is contrary to what might be expected with better PVC fusion (gelation). This article discusses the mechanism involved, which is lubricant inversion, where the lubricant goes from the continuous phase, as a surfactant coating all the PVC primary particle flow units at lower melt temperatures, to become the discontinuous phase at higher melt temperatures. J. VINYL. ADDIT. TECHNOL., 11:57,62, 2005. © 2005 Society of Plastics Engineers [source]