New Siberia Island is noted for abundant upright tree trunks, logs, leaf prints, and other plant debris that occur within sediments that are exposed along sea cliffs and within the uplands of the Derevyannye Hills along its southern coast. Because of the abundance of exposed coalified logs and upright trunks, early explorers and paleobotanists referred to the Derevyannye Hills as either the "Wood Mountains", "Wood Hills", or "Tree Mountain". At one time, the highly folded layers of sand, silt, mud, clay, and brown coal containing these coalified tree fossils were once thought to have accumulated during either the Miocene or Eocene Epoch. These sediments and the fossil trunks and logs, which they contain, are now known to date to the Late Cretaceous Period (Turonian Stage). Baron Von Toll, Dr. Klubov and others, Dr. Dorofeev and others, and other publications all demonstrate that the claims by some authors, i.e. Mr. Southall, that the "Wood Hills" of New Siberia Island are either partially or completely "formed of driftwood" are completely erroneous.