Revisiting Catanduanes Island: calcareous nannofossil biostratigraphy of its Cenozoic formations

摘要

Paleontological studies have been important for stratigraphic correlation and determining the ages of lithologic units in Catanduanes Island, Philippines. The sedimentary rocks have been dated using foraminifera (Tan, 1986; Fernandez et al., 1994; Militante-Matias, 1995; MGB, 2008),ammonites (Tumanda, 1985; Matsukawa et al., 2012),and, most recently, calcareous nannofossils for the Cretaceous formations (Fernando et al., 2014; Magtoto et al., 2014). Despite the number of studies conducted on the island, the age of most Cenozoic formations remains unclear. The present study, therefore,uses calcareous nannofossils in an attempt to confirm and establish the age of the following lithologic units: Bote Limestone (late Oligocene-early Miocene), Santo Domingo Limestone (middle-late Miocene) and Viga Conglomerate (Pliocene-Pleistocene).