biology key ap chapter answer guide tips. The average calculated porosity approaches to the average porosity of laboratory measurements. Ap Bio Cram PacketThe AP Biology exam wants you to know and understand. The equations of porosity versus core porosity were calculated using the method of least square regression and higher values of R2 were obtained. If both of the parameters are added to the dataset simultaneously, the obtained porosity approaches to the laboratory measurements, especially in gas bearing intervals. Effective porosity (total porosity corrected by shale volume) obtained from NMR has a better impact on the initial model compared to shear wave velocity. To improve the characterization, dipole sonic imager and nuclear magnetic resonance (NMR) logs included in the model. Porosity of the cores do not correspond to the calculated properties by the initial model. Since there exists only core porosity, we will validate the model by them. The initial evaluation is based on traditional logging tools such as Gamma Ray (GR), Resistivity Logs, Density, Neutron and Sonic. This paper presents existing methods in evaluation of a gas bearing carbonate reservoir in Persian Gulf and tries to improve the evaluation using new logs. Therefore, to have an accurate hydrocarbon in place estimation, we have to reduce the abovementioned problems in the interpretation. In addition, the existence of gas affects the whole interpretation by underestimating porosity, due to low hydrogen index. Anhydrite content negatively impacts the well log interpretation and complicates carbonates behavior compared to sandstones. The dominant carbonate minerals are dolomite and calcite, commonly associated with a variable content of anhydrite. The existence of organic material increases the complexity, too. Contrary to sandstones, the pore size distribution in carbonates is bimodal or trimodal. create complex pore size distribution in carbonate reservoirs. A workflow for carbonate rock typing addressing some of the industry pitfalls and the differences between lithofacies, petrophysical groups and rock types are presented in this paper.Significant digenetic processes such as dolomitization, chemical dissolution, reprecipitation, fracturing,etc. The authors emphasize on the need to have a good understanding of the original facies, depositional environments, subsequent diagenetic processes and rockfluid interaction (via SCAL) to be able to unravel the relationships between lithofacies, petrophysical groups and rock types. On the contrary, lithofacies deposited in different depositional environments, might exhibit similar petrophysical properties and dynamic behavior. Therefore, lithofacies deposited under similar geological conditions may experience different diagenetic processes resulting in different petrophysical groups with distinct porositypermeability relationship, capillary pressure profile and water saturation (Sw) for a given height above the Free Water Level (FWL). Similar lithofacies, deposited under the same depositional environments, may exhibit different petrophysical properties due to diagenesis. The relationships between lithofacies and reservoir rock types (RRTs) is complex because of the inter-play between facies, diagenetic processes and the rock-fluid interaction (wettability changes) in the reservoir. It is therefore a process by which various petrophysical parameters and dynamic measurements obtained from SCAL are integrated in a consistent manner with geological facies (lithofacies) to estimate their flow (dynamic) behavior. Reservoir rock typing is a synergetic process between geology and petrophysics/SCAL. Porosity, permeability and pore size distributions characterize the rock texture while capillary pressure, relative permeability and wettability describe the rock-fluid interaction. The dynamic behavior of the facies is assessed by studying the rock texture, the diagenetic processes which overprinted the initial fabric, and the interaction between the rock itself and the fluids. Reservoir rock typing is a process by which geological facies are characterized by their dynamic behavior.
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