Peace River Lowlands Subregion
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The Peace River Lowlands Subregion consists primarily of fluvial landforms along the lower Peace, Birch and Athabasca rivers including the
Peace-Athabasca
Delta, one of the largest freshwater deltas in the world. Although the
bedrock is seldom exposed, it influences the character of till deposits and groundwater discharge. The bedrock includes Cretaceous marine
shales and silty shales, Devonian marine
limestones and dolomites, evaporite gypsum and anhydrite, and marine shales and siltstones. Some lacustrine deposits also occur in the Subregion.