Multiple paleosols of the late Albian Boulder Creek Formation, British Columbia, Canada



Fifteen lithified paleosols, closely spaced in vertical sequence, occur in the top 90 m of the late Albian Boulder Creek Formation in the foothills of northeastern British Columbia, Canada. The paleosols have well-developed profiles 0·5 to 1·5 m thick, including A, B and C horizons. The paleosols are characterized by their grey colour, cutans, vertical roots, peds, spherulitic siderite and absence of sedimentary structures. The paleosols formed during a period when one or more basin wide unconformities occurred as a result of either eustatic sea level fluctuations or local tectonic events. These unconformities represent the terrestrial record of a lowered base level which caused valley incision and decreased rates of sedimentation on the incised flood plain. The climate was humid to subhumid. Overall, the environment in which these soils developed was of low relief and subject to little erosion. The water table was high for part of the year but there is also evidence of periodic drying and oxidation of organic debris. Cumulatively, the paleosols in this interval may represent 150000 yr of non-deposition.