High- and low- density Bands (IMAGE) University of North Carolina at Chapel Hill Caption Scanning the coral cores with X-ray computed tomography (CT) reveals annual high- and low- density bands used to measure coral growth. Credit UNC-Chapel Hill Usage Restrictions Photos may be used as long as photo credit is given 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.