Muddy Feet: Dinosaurs Tiptoeing Through Tides

The continents and oceans have changed shape due to tectonics over billions of years, with substantial consequences for a range of Earth system processes, including tides, climate, and evolution. Our view of deep-time Earth comes from palaeogeographic reconstructions, e.g., Scotese and Wright's (2018) digital elevation models (DEMs), which are now used in a range of Earth system models.

Paleo-tidal models are validated using modern analogues and geological proxies, as the named candidate (Jennifer Hewitt) has done (Guo, Fitzgerald, Hewitt et al. 2023; Hewitt et al., three papers in prep). Because tides are sensitive to topography, a correct DEM provides accurate tidal model results. By corroborating the reconstructions, we will validate two key Earth system models concurrently: the DEMs and the tides.

Dinosaur tracks (ichnites) are best preserved in wet mud, such as within the intertidal zone (Lockley et al., 1994; Thulborn, 1990). They are globally widespread in Jurassic (201-145 million years ago (Ma)) and Cretaceous (145-66 Ma) deposits. Here, the locations of ichnites known from the environmental setting to be coastal, will be used to constrain coastline locations in the latest palaeoDEMs.

These will be used to improve new tidal model simulations. This is a logical extension of the candidate's HEFCW-funded MScRes, where novel methods based on fine-scale sedimentary structures were developed to reconstruct coastal palaeotidal conditions from tidally deposited sediments.