Mobile Mass Spectrometry Unit (IMAGE) University of Texas at Arlington Caption Hybrid electric vehicle, which houses the mobile mass spectrometry unit used to take the measurements in front of a pad site in the Eagle Ford shale. Credit Phillip Mach 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.