Temperature and acoustic monitoring for CO2 storage, geothermal and gas wells
Where is the injected fluid going, and is the well behaving?
Where is the injected fluid going, and is the well behaving?
Temperature shows where the fluid went. Acoustics shows what moved. One instrument at the wellhead records both from the same cable, synchronised to GNSS, so an injection event lines up with the wellhead pressure and rate to the second.
- Time-lapse temperature profiles against the pre-injection baseline, with injection and shut-in periods marked.
- Warm-back analysis per depth that shows which intervals took fluid.
- Acoustic energy per depth, synchronised to rate changes, with the acoustic tile.
- Exports shaped for well-monitoring systems, plus netCDF and HDF5 for your own tools.
The event, and the signal
- Fluid is injected at the wellhead. The fibre runs along the casing.
- The fluid enters one layer. That depth cools; the acoustic channel is loud there.
- After shut-in the profile warms back. The slowest interval is the one that took the fluid.
Setup
| Fibre | The downhole cable already behind the casing or on the tubing, single-mode for acoustics, single-mode or multimode for temperature. |
| Depth | To several kilometres of well. |
| Site data | Wellhead pressure, rate and temperature come into the box over Modbus or 4 to 20 mA, so every event has its context. |
| Power | Mains or 9 to 36 V DC at the wellhead. Continuous acoustics needs mains or a generator. |
| Term | A campaign around an injection test, or continuous monitoring on a service contract. |
The measurement
Temperature profiles are recorded every few minutes and differenced against a baseline. During injection the cooling front marks where fluid enters the formation; during shut-in the warm-back rate at each depth separates the intervals that took fluid from those that did not. With the acoustic tile, strain energy per depth is recorded alongside, and the two are shown on one time axis. The engineer concludes; the instrument makes the evidence legible.
Deliverables
- Depth-time heatmap of temperature change with injection periods shaded
- Warm-back half-time per interval
- Acoustic energy per depth beside the temperature panel
- Alarm on sudden change above the casing shoe or at known barriers
On the dashboard, through the API, and as files. All three, always.
Asked before
- Does it need its own cable in the well?
- No. It reads the existing downhole fibre. For a new completion, a cable specification comes with the rental.
- Can several wells share one clock?
- Yes. Each instrument takes GNSS time, so units on different wells line up to the sample.
- Which formats do well-monitoring systems get?
- PRODML and WITSML-shaped exports, plus HDF5 and netCDF, and Modbus for the control room.
Other things the same box does
- Geothermal
What is the ground made of, layer by layer, and is the field slowly cooling?
You get Thermal conductivity and borehole resistance per depth interval, with uncertainty, from one test.
Read more - Pipelines and district heating
Where is the leak, before the road sinks? Hot water, cold water or gas.
You get A per-metre temperature baseline for the route, with every persistent deviation located to the half metre.
Read more - Dark-fibre seismology
Can the telecom fibre under the road become a seismic array?
You get Quantitative strain rate on every channel, not event flags.
Read more
Put your fibre to work.
Tell us about your fibre and your question. You get a call, a plan for your site and a monthly price.