Corbicula fluminalis as a guide fossil

T. Meijer, 2001 (webtext)

In a short communication in Dutch language which was published in 1943, Tesch already pointed to the conspicuous stratigraphical distribution of the fresh water shell Corbicula fluminalis in Dutch Quaternary deposits.
He recognized two levels in which the species is present [translated after Tesch]:

"In the brackish-water intercalation (estuary) in the 'high terrace deposits' between the isle of Schouwen and the village of Voorschoten. Further to the North almost until the provincial border between Noordwijkerhout and Vogelenzang the species also occurs in the fresh-water facies of the high terrace beds.
In the 'horizon van Viviparus glacialis' (or 'horizon van Tegelen') between North- and Middle Limburg and the province of Zuidholland. This is here a strictly fresh water facies. However, the species was already present slightly earlier in the underlying marine layers of the earliest Plistocene."

He noted a large similarity with the occurrence in the surrounding countries, which confirmed his conclusions concerning the Dutch occurrence of the species.

It is striking that he added an illustration which shows the stratigraphical ranges of Corbicula next to the insolationcurve of Milankovi! At that time this was not so self-evident and in this case Tesch was far ahead of his time.

Tesch used the alpine glacial subdivision of the Quaternary which is important to notice for understanding the figure. Nowadays, the interpretation of especially the older alpine glaciations differs from the ideas prevailing in the middle of the twentieth century. Moreover, we now have a better picture of the absolute age of the various ice-ages.
The Würm ice-age is correlated with the Weichselian and the Riss ice-age with the Saalian. Tesch correlated the Günz-Mindel interglacial (not indicated as such in the figure: this is the temperate phase between Mindel-I and Günz-II) with the Tiglian. The Tiglian, however, dates from 1.75 to 2.3 million years ago and is consequently much older than Tesch indicated in the
Milankovi-curve!

The interest of this small paper is not found in these details but in the already mentioned fact of the stratigraphical range of Corbicula, the similarity with neighbouring countries and the early use of the insolationcurve of Milankovi.

LITERATURE

Tesch, P., 1939. De mariene inschakeling in de ’Hoogterrasafzettingen’ in het Westen en Noorden van Nederland. -- Geologie en Mijnbouw 1: 9-13.

Tesch, P., 1943. Corbicula fluminalis als gidsfossiel. -- Jaarverslag Geologische Stichting 1941: 31-33.