CATALYST.Earth

CATALYST Deformation Mapping

Reliably measure and monitor ground deformation with millimeter precision using our leading InSAR workflows

The Basics: Deformation Mapping and InSAR

Detecting changes in the position of the Earth’s surface requires two radar
images of a selected area taken from approximately the same position in space but at two different times. In the illustration on the right, uplift of the ground surface has occurred (in the line of sight of the sensor) between the first and second pass of the satellite, and so the total length of the return signal for the second pass is very slightly shorter than for the first pass.

Specialized InSAR processing algorithms developed by CATALYST can be used to process stacks of repeat pass InSAR images to derive ground displacement information. Our workflows are sensor agnostic thus providing flexibility to select temporal and spatial frequency from a growing list of InSAR capable sensors.

Differential SAR Interferometry (DInSAR)

Differential InSAR (DInSAR) is a technique that can be applied to derive measurements over large surfaces that are less likely to be affected by temporal decorelation, In the example on the left, the semi-arid terrain in the interior of California provides ideal conditions for DInSAR where the ground is highly coherent between passes. Ground deformation measurements can be extracted for all pixels in the image where there is strong coherence. Ground deformation due to steam injection or oil extraction is clearly visible in this location near Bakersfield, California.

Persistent Scatterers Interferometry (PSI)

Most areas in the world experience low coherence, thus requiring a Persistent Scatterer Interferometry (PSI) approach for successful ground deformation measurements to be extracted. In this case, larger stacks of repeat pass InSAR data are required (typically at least 15 images) to determine local targets that have low amplitude dispersion over time. Once these pixels, or groups of pixels are selected, ground displacement information can be extracted by deriving the phase shift information contained in the signal due to ground movement. On the right, a temporal InSAR stack and PSI analysis is shown over Mexico City. Pixels with low amplitude dispersion are color coded to show their cumulative displacement over time. Extreme pressure on fragile aquifers is a known cause of ground deformation in Mexico City.

How to work with our InSAR technology

We offer a number of ways to work with our technology:

  • CATALYST Professional – access to individual algorithms
  • CATALYST Enterprise – pre-scripted workflows for large scale processing
  • CATALYST Microservices – individual workflows deployed to the cloud for on demand processing
  • CATALYST Insights,  Ground Deformation Service – access pre-processed ground deformation information produced by the CATALYST team, delivered via a web interface, or data APIs

Get started today

Speak with one of our expert solution consultants to learn more about CATALYST Microservices.