This paper, published in Geology, summarizes the geologic effects of superplume events: constant magnetic polarity, increased world temperature, increased black shale deposition, increased generation of oil and gas, and increased global sealevel. The author hypothesizes two superplume events during geologic time: during mid-Cretaceous time (124-83 Ma), and possibly during Pennsylvanian-Permian time (323-248 Ma).
