Preliminary Study of High-Resolution Correlation and Calibration of Biodatum Marine Microfossils (Foraminifera and Nannofossils) Using Strontium Isotope Stratigraphy: Case Study in Southern Mountains Central Java - Indonesia

Neogene biostratigraphy of the Southern Mountains Zone (Sambipitu Fm., Oyo Fm. And Kepek Fm.) was published by Kadar (1986), Akmaluddin et.al (2006) and Akmaluddin (2008). The result shows that both formations were deposited during Lower to Upper Miocene (Fig. 4). The purposes of this research are to make a calibration and a correlation of the Southern Mountains biostratigraphy that was published by previous researchers, in each zones/datum by using strontium isotope ratios dating. Twenty Cenozoic samples were analyzed using Strontium Isotope Ratio. The results from strontium ratio showed that the age of Sambipitu and Oyo Formations are &quo