The change in the intensity of the individual wave lengths of radiation comprising said spectrum, with time, is monitored to determine {TAIL ~ the characteristics} of {HEAD ~ the kerogen sample} being analyzed 
The change in the intensity of the individual wave lengths of radiation comprising said spectrum , with time , is monitored to determine { TAIL ~ the characteristics } of { HEAD ~ the kerogen sample } being analyzed
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH