We propose a workshop to develop plans for an ICDP-supported series of shallow boreholes that will recover an almost complete Middle Jurassic sedimentary record at Cabo Mondego, in the northern sector of the Lusitanian Basin, Portugal. The Cabo Mondego record comprises a biostratigraphically (mostly) complete and stratigraphically expanded succession of marine mudrocks and limestones, spanning the Lower Jurassic Toarcian, the Middle Jurassic Aalenian, Bajocian, Bathonian and Callovian, and the Upper Jurassic Oxfordian, including the Bajocian GSSP and the Bathonian ASSP.
The attributes of the stratigraphic succession at Cabo Mondego are ideal for constructing a sorely missing integrated astrochronological, chemostratigraphic, biostratigraphic, and magnetostratigraphic framework for this time-interval, which would allow this succession and ICDP-funded borehole to become the international standard for these (as currently assessed) ~13 million years (~174–161 Ma) of Earth history. The obtained rock materials and data will be applied to construct a comprehensive understanding of the Earth system during the Middle Jurassic, and is expected to significantly improve the Middle Jurassic geological and numerical timescale.

Keywords: Europe, Portugal, Astrochronology, Carbon Cycle, Environmental Change, Middle Jurassic