Reconciling Inconsistent Survey Datasets

We often hear from our clients that one of their biggest challenges with existing survey data is the lack of consistency between datasets. On oil and gas projects there is often hundreds of thousands of dollars invested in survey data that the engineers have little confidence in. The Drilling, Completions, and Facilities Engineers often find mismatches and different accuracies amongst location datasets.

The type of survey data in question comes in many forms – from GPS, theodolite surveys, as-built location drawings, and other surface location data. With so many data sources, it’s not surprising that there are inconsistencies and therefore frustrations for the project engineers.

What all people working on the project need is one reliable dataset as a base. We have worked with oil and gas companies to develop a system for matching surface engineering datasets to our high accuracy elevation surveys and precision satellite photos.

PhotoSat then provides a reliable and coherent package of surface location data including a 1m elevation grid (DEM), accurate to within 20cm vertically. This engineering quality satellite survey data can then be used by the engineers for all future project work.

Mismatched survey datasets

 

Other benefits of having high accuracy satellite survey data:

  • Reduce ground crews needed for surface scouting and site surveying, which reduces costs.
  • Streamline well pad selection and engineering projects for facilities.
  • Accurate cut and fill volume estimates.
  • Use the data for other applications like pipeline and access road route planning, and seismic survey planning.

 

How does reconciling survey data work?

First we produce our 20cm accuracy elevation mapping package from high resolution stereo satellite photos.

The data package includes:

  • 1m bare earth elevation grid accurate to 20cm
  • 1m (or 50cm) contours
  • 50cm precision satellite photo

Then we figure out the relative match between the mismatched engineering datasets that you provide, and our detailed satellite survey. When we determine the data inconsistencies, we work with your team to choose a reference dataset and shift the other datasets horizontally and vertically to match to it. Our system typically results in the final datasets all matching to within 10cm vertically and 25cm horizontally.

In the end we provide you with your original survey engineering data, but now adjusted and verified and therefore reliable. You also receive our elevation mapping package as described above, and usually within about 8 days of the satellite photo collection. Clients then have a coherent suite of surface location data that can be used for future engineering tasks on the project. Our clients tell us having this trust in the data is very valuable, making decisions easier and shortening project timelines.

We completed a case study on reconciling surface data that you can view here for a detailed example.

If you’d like more information on this product or our other mapping services, feel free to contact us at info@photosat.ca or 604-681-9770.