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.

Reconciling Surface Engineering Data

One of the biggest complaints we hear from our oil and gas clients is about inconsistent survey data. On the one hand, they’re spending thousands of dollars on surface engineering data, and the cost is justified because of its business value. That data saves money down the line. Except it doesn’t. Because when drilling, completions and facilities engineers get the data, they often can’t trust it.

It’s data that comes from GPS and theodolite surveys, as-built drawings, and from other sources that aren’t always even identified. Any given data point could have come from any of these sources. Frequently the engineering data is not reliable enough.

What’s needed is a data set that comes from one, reliable source. Then existing data sets can be compared against that. Instead of several differing views, there’s one authoritative, reconciled picture of what’s happening on the ground.

PhotoSat offers our oil and gas clients coherent project location data with elevation accuracies better than 20cm. Completions, facilities and drilling engineers can work from a reliable data set now and in future project stages.

Survey data sets for engineering projects

The value of surface engineering data is directly proportional to accuracy. We help our clients maximize the value of their engineering data by providing reliable data across the project site. That data can be used to inform cut and fill volume estimates as well as to streamline facilities engineering projects and well pad selection.

Additionally, surveying via satellite means less boots on the ground. Fewer survey teams have to work in hazardous working environments and less expensive equipment is exposed to the risk of damage at the project site. Data is also available in a usable form far more quickly, typically within five days.

So how does it work?

We start with the data set our client already has. Then we compare it against our own topographic survey. When we find inconsistencies, we work with the client’s project team to select the appropriate reference data set for that inconsistency, and shift the others horizontally and vertically to match it. This process usually means we’re leaving our clients with datasets that match to within 10cm vertically and 25cm horizontally. Clients also get a matching 1m grid of our satellite engineering topography, accurate to 20cm in elevation, and a 50cm precision satellite ortho photo with 25cm horizontal accuracy. That provides a reliable basis for future data-dependent engineering projects like surface design work, including cut and fill volume estimates.

We’ve delivered over 500 projects like this to clients all over the globe, and our clients know that there’s no better, faster or more accurate way to base their engineering data on something reliable and accurate. If you’d like to read more about how our data reconciliation process works, take a look at this engineering data case study. To find out how we can help you with your project, contact us at  info@photosat.ca or call us at 1-604-681-9770.