What is a Microgravity Survey?
Microgravity surveys are a geophysical technique used to measure very small variations in the Earth's gravitational field. These variations are caused by differences in subsurface density and can provide valuable insights into subsurface structures.
Basic Principle
The method involves using highly sensitive gravimeters to detect minute changes in gravitational acceleration. These changes are influenced by subsurface features such as voids, faults, or density variations in rock and soil.
Key Components
- Gravimeter: A precise instrument to measure gravitational acceleration.
- Base Station: Used for calibration and drift correction during the survey.
- Data Processing Software: Converts raw measurements into interpretable data.
Applications
Microgravity surveys are widely used in various fields, including:
- Detecting subsurface voids or sinkholes
- Mapping geological structures
Advantages
- Non-invasive and environmentally friendly
- High sensitivity to density variations
- Applicable in urban and remote areas
Limitations
- Requires careful calibration and drift correction
- Sensitive to external noise and environmental factors
- Limited resolution for deep subsurface features