Interactive Petrophysics 3. Copy of CPH by download. Search Crain's Petrophysical Handbook on spec2000.net PETROPHYSICS REFERENCE MANUAL and HOME STUDY COURSE. Kansas - Interactive Oil & Gas Field Map - links to all kinds of field and well data including Interactive Petrophysics log analysis software from Schlumberger. CRAIN'S PETROPHYSICAL HANDBOOK Career Paths in Petrophysics Petrophysicists have two main choices in their career path: Specialist Petrophysicists Petrophysical (Technical) Managers In either case, good communication skills and the ability to determine the real problem or request from all the surrounding chaff is necessary.
This article needs additional citations for. Unsourced material may be challenged and removed.Find sources: – ( September 2010) Petrophysics (from the πέτρα, petra, 'rock' and φύσις, 'nature') is the study of physical and chemical rock properties and their interactions with.A major application of petrophysics is in studying for the. Petrophysicists are employed to help and understand the rock properties of the reservoir, particularly how pores in the subsurface are interconnected, controlling the accumulation and migration of hydrocarbons.
Some of the key properties studied in petrophysics are,. A key aspect of petrophysics is measuring and evaluating these rock properties by acquiring measurements – in which a string of measurement tools are inserted in the borehole, measurements – in which rock samples are retrieved from subsurface, and measurements. These studies are then combined with geological and geophysical studies and reservoir engineering to give a complete picture of the reservoir.While most petrophysicists work in the hydrocarbon industry, some also work in the mining and water resource industries.
The properties measured or computed fall into three broad categories: conventional petrophysical properties, rock mechanical properties, and ore quality.Petrophysical studies are used by, and other related studies. Figure 1is used as a relatively inexpensive method to obtain petrophysical properties downhole.
Measurement tools are conveyed downhole using either or method.An example of wireline logs is shown in Figure 1. The first “track”, shows the natural gamma radiation level of the rock.
The gamma radiation level “log” shows increasing radiation to the right and decreasing radiation to the left. The rocks emitting less radiation have more yellow shading. The detector is very sensitive and the amount of radiation is very low. In clastic rock formations, rocks that have smaller amounts of radiation are more likely to be coarser grained and have more pore space, rocks with higher amounts of radiation are more likely to have finer grains and less pore space.The second track over in the plot records the depth below the reference point which is usually the Kelly bush or rotary table in feet, so these rocks are 11,900 feet below the surface of earth.In the third track, the electrical resistivity of the rock is presented.
The water in this rock is salty and the salt in the water causes the water to be electrically conductive such that lower resistivity is caused by increasing water saturation and decreasing hydrocarbon saturation.The fourth track, shows the computed water saturation, both as “total” water (including the water bound to the rock) in magenta and the “effective water” or water that is free to flow in black. Both quantities are given as a fraction of the total pore space.The fifth track shows the fraction of the total rock that is pore space, filled with fluids. The display of the pore space is divided into green for oil and blue for movable water. The black line shows the fraction of the pore space which contains either water or oil that can move, or be “produced.” In addition to what is included in blackline, the magenta line includes the water that is permanently bound to the rock.The last track is a representation of the solid portion of the rock. The yellow pattern represents the fraction of the rock (excluding fluids) that is composed of coarser grained sandstone. The gray pattern represents the fraction of rock that is composed of finer grained “shale.” The sandstone is the part of the rock that contains the producible hydrocarbons and water.Rock volumetric model for shaly sand formation Symbols and Definitions. Figure 2, a petrophysical rock model for clastic rock formationThe following definition and petrophysics model are a typical shaly sand formation model which assumes:1.
Shale is composed of silt, clay and their bounded water which will not flow.2. Hydrocarbon are stored only in pore space in sand matrix.ΦT –Total porosity (PHIT), which includes the pore space in sand and shale.Sw –Total water saturation, the fraction of the pore space occupied by water.Φe –Effective shale corrected porosity which includes only the pore space in sand. The pore space in shale which is filled with bounded water is excluded.Swe –Effective shale corrected water saturation.
The volumetric fraction of Φe which is occupied by water.Vsh – Volumetric fraction of shale. This includes medium to very fine silt plus clay and the shale bound water.Φsh – Shale porosity. Volumetric fraction of pore space in shale. These pore space is filled with bounded water by definition.Key equations:(1-Φe-Vsh) + Vsh + Φe.Swe + Φe.(1-Swe) = 1Sandstone matrix volume + shale volume + water volume in sand + hydrocarbon volume in sand = total rock volumeΦe = ΦT – Vsh.ΦshSee also.References.