Vertek's Oil Detector Probe provides a continuous, real-time output of fluorescence and reflectance over the entire depth of a subsurface sounding. Non-fluorescing oils are detected as a decrease in reflectance compared to clean sand. Fluorescent oils (i.e. dispersed oils) are detected as an increase on the fluorescence channel which is optically filtered to select the characteristic orange 'glow' from dispersed crude oil. The two detections can be viewed graphically in real-time with Vertek’s Data Acquisition System (DAS) as the probe is advanced, providing a more complete characterization of the oil layers vs. depth than other methods.