Coal basins in the Soviet Far East were controlled by tectonic events and to a lesser degree by climate and vegetation. Most of the Early Cretaceous basins developed on the margins of cratonic massifs or on their fold-belt borders. Mid-Neocomian tectonism either reduced coal accumulation inherited from the Jurassic or formed new basins by downfaulting. This tectonism caused an eastward shift in coal deposition and the sites of coal accumulation were pushed farther eastward in the Late Cretaceous when a new tectonic pattern with a coastal volcanic belt-miogeosynclinal trough-island-arc system had emerged. Coal basins extended across the major phytoclimatic boundary at about 50°N while the plant material was supplied by different types of plant communities. However, the rain shadow from volcanic ranges restricted coal accumulation to the miogeosyncline trough where it was further reduced by the rise of the continental margin at the Cretaceous/Tertiary boundary.