the spatial distribution of petrophysical properties within the reservoirs is one of the most importantfactors in reservoir characterization. flow units are the continuous body over a specific reservoirvolume within which the geological and petrophysical properties are the same. accordingly, anaccurate prediction of flow units is a major task to achieve a reliable petrophysical description of a...

We discuss petrophysical analysis of wireline logs, methods for formation evaluation and issues in evaluating tight sandstone formations. The main concerns of log interpretation in tight gas sandstones include porosity interpretation, understanding the effect of clay on the log responses, accurate computation of water saturation, and permeability determination (Kukal et al., 1985). Moreover, va...

[1] We have investigated the potential of combining cross-hole georadar velocity and attenuation tomography as a method for characterizing heterogeneous alluvial aquifers. A multivariate statistical technique, known as k-means cluster analysis, is used to correlate and integrate information contained in velocity and attenuation tomograms. Cluster analysis allows us to identify objectively the m...

Petrophysical information is sometimes available from well logs, laboratory measurements, etc. It has been shown that incorporation of such information into geophysical inversions can greatly improve the recovered models. However, when the known petrophysical information is not applicable throughout the entire region, the application of petrophysical constraints to geophysical inversions could ...

[1] Direct estimation of groundwater solute concentrations from geophysical tomograms has been only moderately successful because (1) reconstructed tomograms are often highly uncertain and subject to inversion artifacts, (2) the range of subsurface conditions represented in data sets is incomplete because of the paucity of colocated well or core data and aquifer heterogeneity, and (3) geophysic...

Biyad Formation is mainly made up of clastic sediments that contain substantial amount of proven crude oil in the eastern Yemen. The Byiad clastic is divided into Upper and Lower Biyad clastic units. Several vertical wells have been drilled and penetrated this formation. This study is concerned with the petrophysical evaluation by means of well log data of the Lower Cretaceous rocks at the East...

Accurate estimation of hydrocarbon volume in a reservoir is important due to future development and investment on that reservoir. Estimation of Oil and Gas reservoirs continues from exploration to end of reservoir time life and is usual upstream engineer’s involvements. In this study we tried to make reservoir properties models (porosity and water saturation) and estimate reservoir volume hydro...

Abstract Downhole data and cores collected during International Ocean Discovery Program (IODP) Expedition 376 at Brothers volcano, Kermadec arc, provide unprecedented, in situ views of volcanic facies fluid pathways an actively forming volcanogenic massive sulfide (VMS) ore deposit. volcano is a submarine caldera with extensive sea floor hydrothermal alteration. were two holes: Hole U1530A the ...

Knowledge of initial water saturation is necessary to estimate original hydrocarbon in place. A reliable assessment of this petrophysical property is possiblewhen rock-coremeasurements ofArchie’s parameters, such as saturation exponent n and cementation exponent m, are available. In addition, chemical analysis of formation water is necessary to measure connate-water resistivityRw. Suchmeasureme...

Tight reservoir means reservoir of low porosity and low permeability. Many tight formations are extremely complex, produced from multiple layers with different permeability that is often enhanced by natural fracturing. The complicity of these reservoirs is attributed to a) Low porosity and low permeability reservoir, b) The presence of clay minerals like illite, kaolin and micas in pores, c) Th...