Gravity with Enhancements

Available Deliverables (Grid, GIS, pdf):

• Free air gravity
  • The total measured gravity field
• Bathymetry
  • Calculated based on the vessel echo sounder data
• Bouguer gravity
  • Free air gravity compensated for bathymetry
• First Vertical Derivative
  • Enhancing short wavelength anomalies caused by sedimentary and shallow basement features
• Second Vertical Derivative
  • As the first derivative, this also enhances the effect of the shallow features and especially the edges of shallow geological features
• 15 km High-Pass filter
  • High-pass frequency filtering of the Bouguer gravity where wavelengths are shorter than 15 km
• 30 km High-Pass filter
  • High-pass frequency filtering of the Bouguer gravity where wavelengths are shorter than 30 km
• 50 km High Pass filter
  • High-pass frequency filtering of the Bouguer gravity where wavelengths are shorter than 50 k
• Horizontal Gradient Amplitude (HGA)
  • Often used to delineate edges of geological features such as basement fault blocks, strike-slip zones, plutons and basin boundaries.
• Coherency filter
  • Useful to detect steep gradients independent of the depth of the feature. Can also be used to calculate approximate depth of source.
• Tilt Angle
  • Useful to detect steep gradients independent of the depth of the feature. Can also be used to calculate approximate depth of source.
• Curvatures
  • This describes how much an edge or surface bends at a given point on a line or surface and can define domes and anticlines.
• First order polynomial residual
  • Highlights the responses from the shallow to mid depth sources, allowing better delineation of sedimentary basins and mini-basins, faulting and trends.