What Is Well Log Interpretation Biology Essay

Development of the construct

Resistivity is a cardinal stuff belongings which represents how strongly a stuff opposes the flow of electric current. In these logs, electric resistance is measured utilizing 4 electrical investigations to extinguish the opposition of the contact leads. The log must run in holes incorporating electrically conductive clay or H2O.Resistivity logging is sometimes used in mineral geographic expedition and water-well boring, but most normally for formation rating in oil- and gas-well boring.

Most rock stuffs are basically dielectrics, while their enclosed fluids are music directors. Hydrocarbon fluids are an exclusion, because they are about boundlessly resistive. When a formation is porous and contains piquant H2O, the overall electric resistance will be low.

Sonic log: Sonic logging shows a formation ‘s interval theodolite clip, designated Dt. It is a step of a formation ‘s capacity to convey sound moving ridges. Geologically, this capacity varies with petrology and stone textures, notably porousness.

Quantitatively, the sonic log is used to measure porousness in liquid filled pores. The sonic tool is merely capable of mensurating travel clip. Many relationships between travel clip and porousness have been proposed, the most normally accepted is the Wyllie clip mean equation. The equation fundamentally holds that the entire travel clip recorded on the log is the amount of the clip the sonic moving ridge spends going the solid portion of the stone, called the stone matrix and the clip spent going through the fluids in the pores.

Principle

A radioactive beginning applied to the hole wall emits medium-energy gamma rays into the formation so these gamma beams may be thought of every bit high speed atoms which collide with the negatrons in the formation. At each hit the gamma beam loses some of its energy to the negatron, and so continues with lessened energy. This type of interaction is know as Compton dispersing.

The scattered gamma beams making the sensor, at the fixed station from the beginning, are counted as an indicant of formation denseness.The figure of Compton dispersing hits is related straight to the figure of the negatron denseness of the formation. Consequently, the negatron denseness determines the response of the denseness tool. Electron denseness is related through equationwhere is the atomic Numberss of all the atoms doing up the molecules in the compound, and M is the molecular weight of the compound.

Deducing porousness from majority denseness

Epithermal neutron tools are characterized by short beginning to detector spacing, which signifies a shallow deepness of probe.Calibration chartCross-plotingBorehole measurings provide an array of recorded or calculated parametric quantities. The parametric quantities normally available are true formation electric resistance Rt, flushed zone electric resistance Rxo, formation majority denseness measurings provide an array of recorded or calculated parametric quantities. The parametric quantities normally available are true formation electric resistance Rt, flushed zone electric resistance Rxo, formation majority denseness i??b, formation denseness porousness i?¦D, formation neutron porousness i?¦N and natural gamma beam radioactivityi?§ .Pattern acknowledgment reading techniques are based on plotting one of these parametric quantities against other. The secret plan is known as Crossplot.

Cross-plotting is a really utile technique. An equivocal relationship between two parametric quantities can be clarified by crossplotting the parametric quantities. Pg.144