12:00 PM - 12:15 PM
[MIS30-P04_PG] A chronostratigraphic study of the upper Anno formation, in the Awa group
3-min talk in an oral session
Keywords:paleomagnetic stratigraphy, oxygen isotopic stratigraphy, chronostratigraphy
We took oriented mini-core samples for paleomagnetic and rockmagentic measurements at 79 sites and rock samples to extract fossil folaminifera from at sites from the upper Anno formation distributed along the Shikoma river. We carried out rock magnetic, paleomagnetic, oxygen isotopic and carbon isotopic measurements. Magnetic carrier was interpreted as pused-single domain magnetites based on the results of hysteresis and thermal demagnetization, thermomagnetic analyses. We carried out analysis of principal component to results from the thermal demagnetization and extracted Characteristic Remanent Magentizations (ChRMs). In the result, a relatively short reversed polarity zone found in the previous study is defined as the Mammoth subchronozone. We obtained an oxygen isotopic curve from the result of isotopic measurements which is correlatable with the LR04 oxygen isotopic standard curve (Lisiecki & Raymo, 2005). Then we detected 6 tie points to establish an age model for this sequence