A new fracture-injection/falloff type-curve analysis method is presented for reservoirs containing slightly compressible and compressible fluids. Type-curve analysis augments conventional beforeand after-closure methods, which are also reformulated in terms of adjusted pseudopressure and adjusted pseudotime to account for compressible reservoir fluids. Unlike beforeand after-closure methods whi...

Hydroseismicity was proposed to explain the occurrence of intraplate earthquakes in regions. Koyna Warna region one of the reservoir triggered seismicity zone in India, which is an example of intraplate earthquake region. The seismicity is continuing after 45 years of impoundment of the Koyna reservoir in 1961 and 25 years of impoundment of Warna reservoir in 1985. The excess of previous maximu...

A thermodynamic approach is presented to classify geothermal reservoir as vapor or liquid dominated. According to it, the vapor dominated reservoir has specific volume of fluid (i.e. combined vapor and liquid) greater than the critical volume of water whereas the liquid dominated reservoir has lesser specific volume. Enthalpy is not a conservative entity in a geothermal system. Apart from it, t...

Elemental sulfur (S8) is often present in considerable amounts in sour gas reservoirs at the reservoir conditions (pressure and temperature). For the isothermal conditions in the reservoir, the reduction in reservoir pressure below a critical value will cause the elemental sulfur to deposit in the formation. Sulfur deposition can cause severe loss in the pore space available for gas, and in tur...

Abstract Steam-water capillary pressure is often either ignored or determined artificially in geothermal reservoir engineering. However steam-water capillary pressure plays an important role in geothermal reservoir performance and may not be substituted by air-water capillary pressure. To this end, preliminary mathematical models have been developed to calculate drainage and imbibition steam-wa...

In this work, studies of underground gas storage (UGS) were performed on a partially depleted, naturally fractured gas reservoir through compositional simulation. Reservoir dynamic model was calibrated by history matching of about 20 years of researvoir production. Effects of fracture parameters, i.e. fracture shape factor, fracture permeability and porosity were studied. Results show...

rock selection in modeling and simulation studies is usually based on two techniques; routinely defined rock types and those defined by special core analysis (scal). the challenge in utilizing these two techniques is that they are frequently assumed to be the same, but in practice, static rock-types (routinely defined) are not always representative of dynamic rock-types (scal defined) in the re...

withdrawal of oil and gas from reservoirs causes a decrease in pore pressure and an increase in effective stress which results to a reservoir compaction. reservoir compaction will result in surface subsidence through the elastic response of the subsurface. usually in order to determine the subsidence above a hydrocarbon field, the reservoir compaction must be first calculated and then the effec...

in this research, a new mathematical modeling on strength changes due to reservoir elastic stresses across the preexisting fault plane is introduced. the method has been applied to the dalpari fault, which is one of the potential seismic sources in the vicinity of the karkheh reservoir. in this method the distribution of total stress across the fault cannot be determined because the initial str...

The conventional determination of pulmonary vascular resistance does not indicate which vascular segments contribute to the total resistance of the pulmonary circulation. Using measurements of pressure and flow, the reservoir-wave model can be used to partition total pulmonary vascular resistance into arterial, microcirculation, and venous components. Changes to these resistance components are ...