Color changes of spores and pollen grains from different modern plants and recent sediments of different sedimentary facies with rising temperatures under laboratory conditions have been observed, and correlations have also been made. Changes in color from yellow through brown to black with rising temperatures are common with respect to all fresh spores and pollen grains either from modern plants or from recent sediments of different sedimentary facies. Nevertheless, at the same temperature there may exist certain differences in color between different sporo-pollen, species. These differences may be attributed to the original differences in the sporoderm thickness and ornamentation of spores and pollen grains. For this reason, sporo-pollen fossils with similar sporoderm thickness and ornamentation are considered as the best candidate to be adOpted in observing their color changes in an attempt to determine the degree of maturation of organic matter in source rocks.
