A CHEMICAL-EXTRACTION TECHNIQUE FOR THE RECOVERY OF SILICIFIED PLANT REMAINS FROM IRONSTONES

Silicified plant remains often appear in Upper Cretaceous terrestrial sediments of the Western Interior Basin of North America. In the past, the fossils have usually been collected after they have weathered out of their encasing matrix or have been studied by means of thin sections or acetate peels. A new acid preparation technique has been developed for extraction of these in situ silicified plant fossils from ironstone rich beds. The technique has yielded both known and unknown types of three-dimensional leaves, seeds, cones and branches showing exquisitely preserved microscopic detail. These fossils will potentially provide new insights into the nature of plants and plant communities in the Cretaceous.