ICDP project is proposed to recover a complete Early Jurassic marine record at the site of a previously drilled borehole at Llanbedr (Mochras Farm), on the eastern margin of the Cardigan Bay Basin, Wales.  The new record would comprise an exceptionally thick (1300 m) and biostratigraphically complete succession of marine mudrocks representing the entire Early Jurassic. The attributes of the succession are ideal to provide the basis for an integrated astrochronology, chemostratigraphy, biostratigraphy, and magnetostratigraphy, which would become the international standard for these 25 million years of Earth history. The new materials and data would be applied to obtain a comprehensive understanding of the Earth system during the Early Jurassic and its history of change, which includes some of the most extreme environmental change events in the Mesozoic.

To summarize, the Mochras project aims to address the following key topics: (i) First biostratigraphically calibrated magnetostratigraphy for the entire 25 Myr-long Early Jurassic based on a single section.(ii) High-resolution continuous cyclostratigraphy for the Early Jurassic; Astronomical Time Scale (ATS); Solar System resonance; length-of-day and tidal dissipation.(iii) Multi-proxy chemostratigraphy to track supercontinent breakup influence on the global earth system. (iv) Record of the Triassic/Jurassic mass extinction and subsequent recovery of the carbon cycle, biosphere and ocean, and effects from CO2 and other volatile releases from the CAMP. (v) Early Jurassic sea level change and the icehouse–greenhouse transition across the Pliensbachian–Toarcian boundary. (vi) Interdependencies among primary productivity, microbial metabolisms, nutrient fluxes and ocean redox state. (vii) Integrated record of changes in atmospheric and marine composition understood in the context of quantitative (viii) whole earth system models. (ix) Order of magnitude improvement in knowledge of Early Jurassic geological timescale through full synthesis of radioisotopic and chonostratigraphic scales.

• Stephen Hesselbo (Exeter)
• Kenneth Miller (Rutgers)
• Christian Bjerrum (Copenhagen)
• Jim Riding (BGS)