| The
following table gives brief
descriptions of
some measurements that are commonly logged in boreholes, and their
applications. |
| LOG | PARAMETERS MEASURED | APPLICATIONS |
| CALIPER | Borehole and casing diameter.(inches) | Fracture identification, lithologic changes, and well construction. |
| NATURAL GAMMA: | Natural Gamma radioactivity. (API ) | Lithologic and stratigraphic correlation, well screen Placement |
| FLUID TEMPERATURE : | Temperature of borehole fluid (deg.F or C) | Indicates geothermal gradient, and water flow within borehole. |
| FLUID RESISTIVITY/CONDUCTIVITY: | Resistivity/conductivity of borehole fluid. (mmhos/cm)(ohm-m/cm) | Indicates water quality interfaces within borehole, . |
| SINGLE POINT RESISTANCE: | Resistance of materials between probe and and ground surface electrode. (ohms) | Lithologic and stratigraphic correlation, fracture identification, placement of well screens. |
| NORMAL RESISTIVITY : | Apparent resistivity of formation material. (ohm meters) | Lithologic and stratigraphic correlation, fracture identification, placement of well screens. |
| SPONTANEOUS POTENTIAL ( SP): | Electrical potentials between probe and surface electrodes (mv) | Lithologic and stratigraphic correlation, water quality. |
| INDUCTION: | Electrical conductivity in formation surrounding borehole. (mmhos) | Lithologic and stratigraphic correlation, in highly conductive environment |
| FLOWMETER: | Continuous or point measurements (RPM) | Identification of permeable zones and water flow in borehole. apparent vertical hydraulic conductivity and flow direction. |
| BOREHOLE COMPENSATED SONIC | Acoustic Velocity (usec/ft) | Total porosity and fracture identification |
| CEMENT BOND | Acoustic amplitude and travel time (bond mv) | Cement to casing bond |
