Houston Interferogram (IMAGE) University of Texas at Austin Caption This is an example of the InSAR measurements. An interferogram can be considered as the difference between two SAR images acquired over the same area at different dates. The color of a pixel represents how much the land surface has moved between the two acquisition dates. Credit University of Texas at Austin. Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.