Product Category
Seismographs & Seismic Systems
Engineering seismographs, exploration seismic recorders, and geophones from Geometrics, DMT, and Geospace Technologies, for reflection/refraction surveys, MASW, blast and vibration monitoring. Available New, Refurbished, Absolute Certified, or Surplus.
What is a Seismograph?
A seismograph (or seismic recording system) captures ground motion as a function of time, generated either by a controlled source — a sledgehammer, weight drop, vibrator truck, or small explosive charge — or by ambient/passive vibration such as traffic, machinery, or actual earthquakes. An array of geophones (ground-motion sensors) connected to a multichannel recorder digitizes the arrival times and amplitudes of seismic waves, which are then processed to image subsurface layering, measure shear-wave velocity, or monitor vibration levels near sensitive structures.
System Types
- Exploration seismographs: Multichannel (12 to 24+ channels per unit, expandable to hundreds via daisy-chained or wireless nodes) recorders used for seismic refraction, reflection, and MASW (multichannel analysis of surface waves) surveys in engineering and near-surface geophysics.
- Engineering seismographs: Compact, often single- or few-channel units used for blast monitoring, construction vibration compliance (e.g. peak particle velocity limits), and structural health monitoring.
- Passive/nodal seismic systems: Autonomous, cable-free geophone "nodes" that record continuously and are later collected for data download — increasingly used for large-N passive seismic arrays and ambient noise tomography.
Geophones & Sensors
Geophones convert ground velocity into an electrical signal via a spring-suspended magnet-and-coil (or MEMS accelerometer in modern nodal systems). Standard natural frequencies range from 4.5 Hz (favoring deeper, lower-frequency energy) to 100 Hz (favoring shallow, high-resolution work); vertical, horizontal, and 3-component geophones are all available depending on survey requirements (P-wave vs. S-wave/surface-wave acquisition).
Key Specifications
Important specifications include channel count and expandability, sample rate (typically up to several kHz for exploration seismographs, lower for engineering vibration monitors), trigger modes (STA/LTA ratio, fixed threshold, or external trigger from a source), dynamic range and A/D resolution (bits), and connectivity — traditional cabled multicore takeouts versus modern wireless/nodal acquisition.
Seismograph Brands We Supply
| Brand | Origin / Parent | Known For | Typical Application |
|---|---|---|---|
| Geometrics | Independent (USA) | Multichannel exploration seismographs and geophone systems for refraction/reflection and MASW | Near-surface & engineering geophysics |
| DMT | Independent (Germany) | Seismic and vibration monitoring systems, blast monitoring instrumentation | Mining, construction, structural monitoring |
| Geospace Technologies | Independent (USA) | Geophones, seismic sensors, and nodal acquisition hardware for exploration and monitoring | Exploration & passive seismic arrays |
Condition Tiers for Seismic Equipment
Factory New
Sealed recorder and geophones direct from the manufacturer, current firmware, full OEM warranty.
Refurbished
Recorder channels and geophone coils tested individually, connectors and takeout cables inspected or replaced, function-tested before dispatch.
Absolute Certified
Every channel bench-verified for noise floor, timing accuracy, and amplitude response against a reference source; calibration certificate issued at handover.
Surplus
Decommissioned survey-crew inventory (recorders, geophones, cables), sold functional and as-is — a common source for expanding channel counts affordably.
Frequently Asked Questions
Can I mix New and Surplus geophones on the same seismic recorder?
Generally yes, provided the geophones share the same natural frequency and impedance. Mismatched frequency geophones on the same spread can complicate later processing (different phase and amplitude response per channel), so we recommend matching geophone type across a spread — but recorders and geophones themselves don't need to be the same condition tier or even the same acquisition vintage.
What does "Absolute Certified" mean for a multichannel seismograph?
It means every recording channel has been individually bench-tested for noise floor, gain accuracy, and timing synchronization against a reference signal source, with any faulty channels repaired or the unit re-graded before sale. You receive a calibration certificate documenting the per-channel test results at handover.
Do you supply nodal (cable-free) seismic acquisition systems?
Yes, where available in the condition tier you need. Nodal systems are a newer technology category than traditional cabled seismographs, so New and Refurbished availability is generally stronger than Absolute Certified or Surplus for these — ask us for current stock when requesting a quote.