A geological and paleomagnetic study of the Hyblean volcanic rocks, Sicily

Abstract

The geological and paleomagnetic study of the Hyblean volcanic rocks in southeastern Sicily permits the following conclusions: 1. (1) The Upper Cretaceous volcanics are considerably more extensive than earlier studies indicated, they stretch from north of Augusta to the vicinity of Siracusa. Their magnetization is identical to that of the better known outcrops around Capo Passero. Of the two new age dates reported here, one is younger than any so far reported. 2. (2) The Upper Tortonian flows are normally magnetized, suggesting a correlation of the Carlentini Formation with magnetic interval 7. The flows at the top of the Tellaro Formation are also normally magnetized and are tentatively correlated with the Carlentini Formation flows. Shorter reversed intervals within interval 7 may be represented by two less well-dated flows. 3. (3) The lowest Pliocene flows have an adequate stratigraphie control and their magnetization is consistent with the extrusion of the pillow lavas during the Mammoth event. The Militello flow sequence together with the Francofonte flows appear by indirect argument to lie within the oldest reversed interval, i.e. pre-Kaena, of the Matuyama epoch. The individual flows in which both normal and reversed directions have been found cannot be assigned positions in magneto-stratigraphie scale. 4. (4) The geomagnetic pole positions are consistent with that of the African plate during the Cretaceous, and a European plate location during both Pliocene and Miocene time. The pole positions are: Upper Cretaceous 212.3°E, 69.3°N. Upper Miocene: 200.9°E, 82.1°N. Pliocene 339.3°E, 85.9°N.