Astronomical tuning of the Paleocene Contessa Highway section (Gubbio, Italy)

• Grant number: 12/18302-0
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: January 01, 2013
• End date: December 31, 2013
• Field of knowledge: Physical Sciences and Mathematics - Oceanography - Geological Oceanography
• Principal Investigator: Luigi Jovane
• Grantee: Ianco Morais Mariano Rodrigues
• Host Institution: Instituto Oceanográfico (IO). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

This project consists in performing the astronomical tuning and calibration of an interval of the Contessa Highway Section (CHS), between 16 and 24 msl, corresponding to ~58 to 60.5 Ma. Initially, it will be elaborated a detailed age model based on biostratigraphic and magnetostratigraphic events occurring in the studied interval. It will be studied through spectral analysis techniques to recognize the periodicity present in the data, which consists of measurements of calcium carbonate, stable isotopes of oxygen and carbon, and magnetic properties realized along the section. The age model obtained will be used to constrain the orbital signal observed in the paleoclimatic proxy and perform the tuning based on the astronomical target solution of Laskar et al. (2011). Thereafter, wavelet analysis and Evolutive spectra will be used to define where the periodicities are concentrated and test the continuity and stability of the spectral power caused by astronomical cycles over the interval of the data. Gaussian and Notch filters will be used to isolate the main astronomical frequencies in the data, enabling to investigate of which orbital cycles have a greater influence on data. After completion of the above steps, will be realized the tuning and the calibration in the age model, then, further cross-spectral analysis between the tuned data, based on the new calibrated age model, and target curves to evaluate de coherency obtained with the new age model. This project offers an innovative study on the influence of the Milankovitch cycles on Earth´s climate evolution, enhancing a greater understanding of the role of astronomical cycles in climate pacing. Furthermore, this type of study favors the development of techniques applied to the investigation of geological sections and cores, allowing obtaining age models increasingly precise.(AU)