Case Study | Microtremor Survey Accurately Delineates Goaf Areas in Ningxia Coal Mine
Apr 03,2026
To support national mine safety policies and prevent major accidents, a microtremor survey was commissioned in a Ningxia coal mining area (Ningdong region). The terrain is low hills covered by aeolian sand, with harsh conditions (large temperature swings, frequent sandstorms). Target detection depth: ≤200 m.
Parameter Optimization
Tests on Line L10 determined the optimal array radius (50 m) and acquisition duration (30 min). A 50 m radius achieved detection depth >250 m with clear dispersion curves; 30 min met the Technical Specification for Microtremor Survey requirements.
Equipment Advantages – GN309 Node Seismograph
Wireless deployment – 2,014 stations deployed in 32 days.
Real-time monitoring (4G) – Check rate 5.1%, RMS relative error 2.96% (well below 5% standard).
IP68 protection – Operates stably from -40°C to +85°C, resisting sandstorms and temperature fluctuations.
Results
Detection depth exceeded 250 m (some >300 m), satisfying ≤200 m requirement.
Goaf areas appear as continuous low-velocity anomalies (blue/green) in apparent S-wave velocity profiles.
Verified against known geology and mine maps – high consistency.
Additional hazard identified: subsurface fire zone (concave low-velocity anomaly on lines 7 & 8).
Conclusion
The GN309 system proved highly effective for microtremor surveys in complex desert environments, providing reliable technical support for goaf delineation and hidden hazard screening in coal mines.
BLOG
CONTACT
Tel: 0086-0551-65327898 / 65327899
Fax: 0086-0551-65327899
E-mail: hfgwe@hfgwe.com
Add: 9th Floor, Building A, G3, Phase II, Innovation Industry Park,No. 2800 Innovation Avenue, High-tech Zone, Hefei city,Anhui Province, China
Mobile website
Hefei Guowei Electronics Co., Ltd.
Subscribe Us
We will contact you within one working day. Please pay attention to your email.
CopyRight:Hefei Guowei Electronics Co., Ltd. Powered by 300.cn SEO