Webinar
Webinar: Getting the most from your GPR Utility Data
Utility locators using GPR learn early that subsurface objects are indicated by hyperbolas, but they also learn that not all hyperbolas are utilities; they can be rocks, metal debris or other objects of no interest. In this webinar, we learn how GPR reflections from utilities occur, what affects them and several strategies, such as the use of depth slices, GPS and interpretations, to get the most out of your utility-locating GPR data.
- 0:00 – Introduction
- 1:05 – How GPR detects utilities
- 3:05 – Agenda
- 3:35 – Why do GPR waves reflect from objects like utilities?
- 4:30 – GPR Reflections from contrasting layers
- 6:10 – What controls how much GPR energy reflects from an object or boundary?
- 13:00 – The effects of water in the soil for detecting objects
- 15:49 – GPR images the contrasts in the subsurface
- 17:43 – GPR signal attenuation limits the depth of GPR penetration
- 21:05 – Stacking more increases GPR signal depth of penetration
- 30:05 – How to “gain” GPR data properly
- 32:12 – Applying a Background Subtraction filter to emphasize hyperbolas
- 34:12 – The advantages of GPR grid collection for locating utilities at complex sites
- 35:10 – GPR grid data processed into depth slices
- 37:10 – Using GPS to position “pseudo grid” or “random walk” GPR data
- 38:39 – Depth slices cannot map targets with a weak response
- 39:50 – Adding interpretations to weak hyperbolas
- 41:08 – SplitView screen – cross-section and map image simultaneously
- 42:18 – Locating utilities at sites with many hyperbolas
- 44:00 – Data collection perseverance
- 44:29 – Summary
- 45:39 – End