Much of the basin that had been transformed into the Great Lakes by the Laurentide Glacier during the last ice age was formed by seismological events that occurred nearly one billion years earlier.

Much of the basin that had been transformed into the Great Lakes by the Laurentide Glacier during the last ice age was
Much of the basin that was transformed into the Great Lakes by the Laurentide Glacier during the last ice age had been
Much of the basin that was transformed into the Great Lakes by the Laurentide Glacier during the last ice age has been
The Laurentide Glacier during the last ice age transformed the Great Lakes from much of the basin that has been
During the last ice age, much of the basin that was transformed by the Laurentide Glacier into the Great Lakes had been