E-Log Electric Logging Services

What Is E-Log (Electric Logging)?

An E-Log is a geophysical survey that measures the electrical properties of the rock formations your well passes through. By lowering a probe into an open borehole, we record how different layers of earth respond to electrical signals. The data tells us what type of rock is at each depth, where the water-bearing zones are, and how good that water is likely to be.

This is the most common and fundamental well logging service. If you are drilling a new well, an E-Log gives you the data you need to design it correctly — where to set screens, where to grout, and what to expect from the aquifer.

Why E-Logs Matter

Every borehole passes through multiple geological formations — sand, clay, limestone, shale, gravel, and more. Without geophysical logging, you are relying on drill cuttings and a driller's observations alone. That approach often cannot distinguish between similar-looking formations or accurately determine their depth, thickness, and water potential.

The result? Improperly placed well screens, inadequate gravel packing, poor water quality, low well yield, or costly well failures. An E-Log eliminates that guesswork.

What We Measure

Our digital logging probe captures multiple measurements simultaneously as it is drawn through the borehole:

• Normal Resistivity (8, 16, 32, 64-inch) — measures electrical resistance at four depths of investigation. High resistivity means clean sand, gravel, or limestone; low resistivity means clay or shale.
• Spontaneous Potential (SP) — records natural electrical potential at formation boundaries. Useful for finding permeable beds and estimating water salinity.
• Single Point Resistance (SPR) — high-resolution bed boundary detection that complements resistivity data.
• Natural Gamma Ray — measures natural radioactivity to distinguish clean formations from clay-rich ones. Works in both open and cased holes.
• Caliper Log (3-Arm / XY) — continuously measures borehole diameter to find washouts, tight spots, and ledges. Essential for cement volume calculations and casing design.

How This Data Helps You

• Screen placement — identify the most productive aquifer zones and their exact depths.
• Water quality assessment — estimate total dissolved solids (TDS) and salinity at different depths without expensive pump testing.
• Formation correlation — tie geology between multiple wells for comprehensive hydrogeological mapping.
• Casing and grouting design — use caliper and lithology data for proper casing programs and accurate grout volumes.
• Aquifer characterization — map aquifer geometry, thickness, and lateral extent.

Common Applications

• Water well drilling — municipal, agricultural, and domestic water supply well evaluation.
• Environmental monitoring — contaminated site characterization and monitoring well design.
• Geotechnical investigation — subsurface characterization for construction and infrastructure projects.
• Mining exploration — delineating ore bodies and mapping formation boundaries.

Available 24/7

Our E-Log teams operate around the clock so your drilling schedule is never delayed waiting for logging. Our field engineers provide preliminary observations at the well site, with complete digital files and printed presentations delivered promptly after the survey. Call 1-877-495-9121 anytime.