Golden Torc - 2 (55 page)

Apologia Pro Geologia Sua

Map of Northwestern Europe

During the Pliocene Epoch

Map of Western Mediterranean

Region During the Pliocene Epoch

Map of Eastern Aven (Balaeric Peninsula)

During the Pliocene Epoch

APOLOGIA PRO

GEOLOGIA SUA

THE ANCIENT LANDSCAPE DEPICTED IN THIS SAGA REPRESENTS Europe during the so-called Mio-Pliocene Regression, when the Mediterranean was at its lowest ebb prior to the opening of the Straits of Gibraltar. The timing of the latter event has not been firmly established, but it may have taken place about 5.5 million years before the present, and I have rounded off this figure to 6 million years. During the Miocene Epoch, the Mediterranean Basin received Atlantic waters via two channels that opened and closed a number of times-the Betic Channel in southern Spain and the Rif Channel, which extended across northern Morocco, Algeria, and Tunisia. The rupture at Gibraltar took place after the Rif and Betic channels had closed. With the opening of the Gibraltar Gate, the filling of the Mediterranean might have been a fairly rapid thing; perhaps only a hundred years after the cataclysm, influx from the Atlantic would have filled the basin of the Empty Sea completely, drowning the ancient Valley of the Rhone almost as far north as Lyon, and undoubtedly initiating tectonic adjustments that not only altered the Mediterranean floor into its present topography of abysses and shallows but also caused profound mod-ification of the geology of the Italian peninsula, Sicily, and other unstable regions.

The map of the Empty Sea that I have drawn is entirely speculative, especially in its treatment of the Southern Lagoon Estuary, the Great Brackish Marsh, and regions now known as the Alboran Sea and the Algerian Basin. There are, however, volcanic remnants that make my rubble dam at least remotely plausible; vis. at Cabo de Gata; at Cap de Trois Fourches, Morocco; and of course at Isla de Alboran itself. I have postulated that Pontian flora and fauna were contemporaneous with the Mediterranean flood. The climate, geography, vegetation, and animal life of Pontian times are essentially as set forth in the novel-but geologists and paleobiologists will be quick to detect a few fudgings that I hope can be forgiven in the spirit of good fun. Ramapithecus, that enigmatic and fascinating hominid of many aliases, is placed as late as the Pontian by virtue of a jaw described in 1972 by G. H. R. von Koenigswald, to which he gave the name Graecopithecus freybergi.

The structure called the Ries (or Rieskessel) is the subject of some controversy-one school of thought accepting it as an astrobleme, while another holds it to be the result of a cryptovolcanic explosion that brought to the surface "meteoritelike" materials. Arguments for the latter viewpoint are summarized in G. H. J. McCall, Meteorites and Their Origins (New York: Wiley, 1973). The more dramatic impact hypothesis is elegantly supported in E. Preuss, "Das Ries und die Meteoriten-Theorie" Stuttgart:Fortschritte der Mineralogie, The only other events remotely comparable to the flooding of the Mediterranean were the "Great Missoula Roods," which took place during the pleistocene Ice Age in western North America. Melt waters from the Cordilleran Glacier of the Rocky Mountains flowed toward the west until they met a lobe of the Okanogan Glacier. which blocked Clark Fork Valley near the present Lake Pend Oreille in northern Idaho. This formed Glacial Lake Missoula, one of the largest freshwater bodies ever to collect in the western part of the continent. More than a thousand feet deep in some places, it inundated the valleys of western Montana until the natural dam of ice and rubble broke. Some 500 cubic miles of water drained from the lake through the Grand Coulee within a period of about two weeks, scouring the Washington landscape known as the Channeled Scablands and draining into the Pacific through the Columbia Gorge. Hydraulic damming in the gorge piled the flood waters some 400 feet above sea level in the region adjacent to Portland, Oregon. The flooding was apparently repeated a number of times. In comparing the Missoula Roods to the filling of the Mediterranean, one should recall that the Mediterranean Basin nowholds about one million cubic miles of water; but in early Pliocene times, the basinis presumed to have been much shallower.

1964, 41:271-312). McCall seems not to have considered the Preuss material in his later survey. In my novel, trajectory, velocity, and mass data are from Preuss. Both K/Ar and fissiontrack testing of the Moldavite tektites (usually considered of identical age with the Ries) yield-alas!-an approximate age of 14.7 ±0.7 million years.