Vehicle-mounted Distributed Fiber-Optic Acoustic Sensing System

Zitn's High-Precision Vehicle-mounted Distributed Acoustic Sensing (DAS) is an advanced sensing technology that enables continuous, distributed detection of vibration and acoustic fields. It utilizes a narrow-linewidth laser and coherent Rayleigh backscattering, combined with OTDR principles, to monitor minute environmental changes in real-time. This provides highly sensitive and reliable monitoring for applications such as oil & gas well logging and pipeline surveillance.

Applications

1. Real-time Monitoring of Hydraulic Fracturing

• Application Description: Permanently or temporarily deploy DAS fiber in offset or parent wells to listen for microseismic events and acoustic signals generated by fluid flow during fracturing operations.

• Value:

• Track fracture geometry and height in real-time.

• Identify formation layers receiving fracturing fluid (fracture injection profile).

• Evaluate fracturing efficiency and optimize stage spacing and treatment parameters.

2. Production Profiling & Multiphase Flow Monitoring

• Application Description: Analyze acoustic signatures induced by fluid flow (oil, gas, water) to identify production characteristics of individual zones.

• Value:

• Distinguish between gas and liquid flow and determine their velocities.

• Quantitatively or qualitatively assess contribution from each producing zone.

• Detect early water or gas breakthrough to guide water/gas shutoff strategies.

3. Injection Monitoring (Water/Gas)

• Application Description: Utilize DAS in water or CO₂ injection wells to monitor flow paths and distribution of the injected fluid.

• Value:

• Identify dominant water/gas receiving layers.

• Detect "fingering" or early breakthrough along high-permeability channels.

• Evaluate sweep volume and enhance displacement efficiency.

4. Well Integrity & Leak Detection

• Application Description: Use DAS to identify acoustic signals generated by anomalous fluid movement (e.g., gas leaks, inter-zonal flow) outside casing or in annuli.

• Value:

• Locate casing damage, cement bond failure, or packer leaks.

• Monitor micro-leakage caused by abnormal annular pressure.

• Support well remediation decisions, reducing environmental and safety risks.

5. Vertical Seismic Profiling (VSP) & Passive Seismic Monitoring

• Application Description: DAS transforms the entire wellbore into thousands of high-density geophones, enabling active-source VSP or passive listening for microseismicity.

• Value:

• Acquire high-resolution subsurface imaging to aid reservoir modeling.

• Monitor microseismic activity during reservoir development (e.g., CO₂ migration in CCUS projects).

• Serve as a lower-cost, more continuously covered alternative to conventional wireline seismic logging.

Technical Specifications