Case Study: Defensible Subsidence Monitoring Over a Legacy Underground Block Cave
Project Overview
A large underground mining operation with a legacy block cave required improved visibility of surface subsidence impacting access roads, surface infrastructure, and workforce safety. Historical monitoring was constrained by line-of-sight limitations, personnel exposure to unstable ground, and discontinuous datasets. Kurloo was deployed as an independent, GNSS-based surface monitoring system, delivering continuous, real time deformation data to validate predictive models and support proactive risk management.
The Challenge
The subsidence zone intersected critical access roads and infrastructure corridors, meaning undetected or accelerating movement posed material safety, operational, and logistical risks. Prior to Kurloo, surface deformation monitoring relied primarily on Total Station surveying, creating several challenges:
- Line-of-sight constraints from terrain, vegetation, infrastructure, and progressive ground movement
- Safety exposure, requiring personnel to access potentially unstable ground within the subsidence zone
- Intermittent data capture, limiting early detection of accelerating movement
- Inconsistent datasets, reducing confidence when reconciling monitoring data with predictive models
InSAR formed part of the monitoring strategy but its spatial resolution and revisit frequency limited its suitability for critical asset-level, operational decision-making without ground-based validation.
The Solution
Kurloo deployed a networked GNSS monitoring system across the subsidence zone to deliver:
- Continuous, automated displacement monitoring across high-risk areas
- Real-time alerts linked to pre-defined movement thresholds
- Targeted coverage of access roads, infrastructure, and critical surface assets
- No requirement for routine, high-risk field access
Kurloo’s high-frequency GNSS data was used as an independent reference to validate numerical modelling outputs and provide confidence that predicted cave behaviour aligned with measured surface response. InSAR continued to play a complementary role, offering broader spatial context, while Kurloo delivered ground-truth, high-resolution data at locations critical to operational risk.
The Results
Kurloo delivered continuous, defensible surface monitoring that strengthened confidence in predictive models and removed personnel from high-risk areas:
Continuous GNSS data provided a reliable ground-truth reference to validate predictive modelling and measured surface response.
RAW GNSS observations could be revisited, reprocessed and independently verified to confirm movement trends with confidence.
Automated monitoring reduced the need for routine field access in unstable subsidence-zone areas.
The ability to revisit raw data and independently verify outcomes provided a level of transparency, traceability, and confidence beyond processed-output-only monitoring approaches.
Data Integrity and Defensibility
Kurloo enabled:
- RAW GNSS observations recorded at every device — not just processed outputs
- Independent reprocessing against multiple reference points to verify results
- Forensic data validation when a discrepancy emerged between InSAR and GNSS data, confirming detected movement was real, repeatable, and accurately quantified
- Full transparency and traceability supporting auditability and long-term confidence
Outcome
For legacy underground operations, subsidence progression is often expected. Kurloo does not replace modelling or InSAR — it strengthens them. By delivering continuous, defensible, real time GNSS data, Kurloo enables operations to validate predictive models with confidence, act early as conditions evolve, and protect people, infrastructure, and access — before risk becomes disruption.
Download the Full Technical Case Study
Access the full case study, including the monitoring approach, data defensibility process, and performance comparison.