- the supposed approximate courses of the Ancestral Thames, and of other possible rivers, in the Late Oligocene epoch (around 30 million years ago); and
- (blue line) the Late Pliocene - Early Pleistocene incursion of the North Sea into the London Basin (around 3 million years ago).
Sources:
- Gibbard, P.L. & Lewin, J., 2003, "The history of the major rivers of southern Britain during the Tertiary", Journal of the Geological Society, 160, pages 829-845. Oligocene section, and Neogene (Miocene and Pliocene) section. Online at www.qpg.geog.cam.ac.uk.
- Gibbard, P., "North West European Rivers - 2. Late Pliocene - Early Pleistocene", Quaternary Palaeoenvironments Group. Online at www.qpg.geog.cam.ac.uk.
to share – to copy, distribute and transmit the work
to remix – to adapt the work
Under the following conditions:
attribution – You must give appropriate credit, provide a link to the license, and indicate if changes were made. You may do so in any reasonable manner, but not in any way that suggests the licensor endorses you or your use.
share alike – If you remix, transform, or build upon the material, you must distribute your contributions under the same or compatible license as the original.