Geothermal exploration in the Perth Basin, located in Western Australia, focuses on identifying and assessing geothermal resources for potential energy production. The Perth Basin is a significant geological feature that extends from the northern part of Perth to the southern coastal areas, characterized by a series of sedimentary formations that could potentially host geothermal resources.
Australia Geothermal
Reading a hot sandstone aquifer — and its temperature — from surface, at the Jingemia field in the Perth Basin, Western Australia.
See before you drill.
Evidence tier — Validated · with a Candidate deep target
A reservoir mapped from surface — and an honest line on the deep temperature
A hot-sedimentary-aquifer play lives on hot, porous, permeable sandstone kilometres down. Over the Jingemia field in the Perth Basin, ADR built a fence of virtual boreholes from surface and was held up against known well and seismic control, to test two things: could it map the target sandstones, and could it estimate temperature at depth?
Calibrated at a tie point on the Jingemia‑1 petroleum well, the ADR energy fence resolved and correlated the Wagina Formation across the survey (JT‑0 to JT‑800), in agreement with the seismic top‑Wagina interpretation. The depth–temperature model fit tightly within its calibrated interval. Because that model was trained on relatively shallow, high‑temperature intervals, the estimate for the ~3 km High Cliff Sandstone target is an extrapolation — reported here as a Candidate, not a confirmed deep temperature.
Can a geothermal reservoir — and its temperature — be read from surface?
A deep geothermal well is a costly bet on sands you cannot see: get the depth, thickness and temperature of the reservoir right and the well flows; get them wrong and a multi-million-dollar hole disappoints. The geothermal prospect here sits mainly with the High Cliff Sandstone at roughly 3 km, where the nearby petroleum exploration well Jingemia‑1 recorded porosities above 20% and a corrected temperature of about 123 °C — the porosity, permeability and heat a hot-sedimentary-aquifer play needs.
ADR directs coherent, pulsed electromagnetic energy into the ground and reads the returning energy, frequency and dielectric response to build a virtual borehole — a depth log acquired from surface, without drilling. A virtual borehole (VB1) at the collar of the vertical Jingemia‑4 intersected the base of Jingemia‑1, giving a tie point that anchored the interpretation to known lithology and temperature. Fieldwork and analysis were carried out under Adrok; the technology and IP are now carried forward and developed by VEXRAD.
A fence of virtual boreholes, tied to a well
Acquisition used ADR virtual boreholes along a fence of stations, supported by wide-angle reflection & refraction (WARR) scans — one antenna held stationary while the other moves along the line to characterise velocity structure. Existing seismic provided time-to-target control and an interpreted top of the Wagina Formation to anchor the fence. Temperature was then estimated in two steps: a calibration model related depth to temperature at the tie point, and that relationship was inverted into a predictive model estimating temperature from each ADR-picked layer depth.
Assessed against the well and the seismic
Each finding is tagged with the evidence tier it earns — confirmed against ground truth, expected from the physics, or an untested target.
| Finding | Evidence | Tier |
|---|---|---|
| Wagina Formation resolved and correlated across JT‑0 to JT‑800 | Matches the seismic top-Wagina interpretation and the Jingemia‑1 tie point | Validated |
| Kockatea & Carynginia shales picked | E-ADR energy peaks fall at the logged shale intervals across the fence | Validated |
| Depth–temperature model (in calibrated range) | Strong, statistically significant fit at the tie point (R² 0.9995, 97 d.f., p<0.001) | Grounded |
| High Cliff temperature at ~3 km (~123 °C target) | Extrapolated beyond the ~600 m training range; not drilled by this survey | Candidate |
What this doesn’t claim
- This was an early applicability test, tied to a single well and the seismic — the strength of the reservoir-mapping result comes from that calibration.
- The temperature model was trained on relatively shallow (~600 m), high-temperature intervals; the ~3 km estimate is an extrapolation, and the drift between predicted and calibration temperature grows with depth.
- No independent deep drilling confirmed the High Cliff prediction in this survey, and no true-negative control was designed in — so the deep target is a Candidate, not a validated result.
- Formation depths in the schematics are indicative; the figures are VEXRAD reconstructions of the survey data.
We report these plainly. A result is only worth as much as the honesty around it.
What it means for geothermal developers
A deep geothermal well is a large, largely irreversible bet on a reservoir you cannot see. This work shows ADR mapping the target sandstones from surface and modelling temperature within a calibrated interval — with the deep target flagged honestly rather than oversold. Calibrate ADR against a well or two in a basin, and extend that control deeper, and the temperature prediction firms from Candidate toward Validated — de-risking the next target before the rig arrives.
Talk to us about a geothermal survey on your ground
See before you drill.
ADR survey and figures by Adrok (Vol 4 “Together We Rock”; survey ref GSPA‑001, virtual borehole VB1 / Jingemia‑1, Perth Basin). VEXRAD is the successor company holding the ADR technology, data and copyright. Figures are VEXRAD reconstructions of the survey data. Confirm the survey year and the client’s consent before publishing in named form; anonymise if preferred. Findings reported under VEXRAD’s four-tier evidence framework.
Gordon Stove
Founder & Technical Director
gstove@vexrad.com · +44 (0)7939 051 829
vexrad.com