Relationship of Fossil Tree Stumps to Coal Seams
In eastern Kentucky, fossil tree stumps have been recorded above at least 13 coal beds, and likely occur above many more. Coal beds formed in peat swamps. The plants that live in modern peat swamps are adapted to living in wet, peaty soils, often with standing-water cover. Similar situations are assumed for the trees that formed in Kentucky’s coal beds. There is sometimes a misconception, however, that all fossil standing tree stumps represent trees in the coal swamps that were preserved when the peat-forming coal was buried. Some stumps, which are rooted into the coal represent coal-forming swamp trees. Most fossil tree stumps, however, are not rooted in underlying coal beds, but rather are found in rock strata between coal beds. Some occur beneath the coal or near the top of the coal. Others may occur tens of feet above coal beds. These stumps belonged to trees that were living in floodplains, along lakes, and in estuaries, rather than in peatlands. Many of the trees were still living in wetlands, just not peat-forming wetlands. The term “clastic swamps” (Gastaldo, 1986) is sometimes used to differentiate the plant fossils found in the rocks (shale, siltstone, sandstone) between coal beds from the plants found in the coal itself, which represent ancient peat swamps, sometimes termed “mires.”
See Photographs of Standing Fossil Tree Trunks