Scientific Webinars

Bedforms are a key tool to reconstruct sedimentary processes in modern and ancient environments. This talk will present novel mixed sand-mud bedforms which have different shapes and sizes compared to pure-sand bedforms, and are found in the fringe of submarine fans. These striking mixed sand-mud bedforms are interpreted to be produced by sediment gravity flows with transient-turbulent fluid dynamics, due to the presence of cohesive clay. The presence and spatial trends in mixed sand–mud bedform types may be an important tool in interpreting fan fringe environments.

Join us as we explore the diverse world of Sedimentology. Drawing from a tranche of past BSRG talks and more, examples will be presented of sedimentary structures in ice and snow, the desert, the sky as well as more conventional settings. Prepare to be baffled by some real head scratchers and wowed by some of Earth’s largest ever structures, and finally head into space to speculate on the sedimentology of exoplanets.

Kathleen is a science team member for Mars 2020, This talk will give an overview of halite and gypsum on Mars and describe their potential to host microorganisms and organic compounds as solid inclusions and within fluid inclusions – as salt minerals on Earth do. The talk will place the search for life in salt minerals on Mars in context of the sample return plan for the Perseverance rover.

The threat posed by plastic pollution to ecosystems and human health is under increasing scrutiny and the amount of mismanaged plastic waste entering the environment is growing at a staggering rate. In particular microplastics (plastic particles <1 mm in size) have been discovered in every sedimentary system on the planet and thus became a new type of sediment particle. As such, sedimentology represents an important and powerful tool to understand and predict the transport, dispersal, and ultimate fate of microplastics in different environments. However, due to the complex shapes and low densities the transport and sedimentation behavior of this new sediment particle may differ significantly from those of natural sediments. The presence of microplastics in the environments poses new challenges for the field of sedimentology, but may also provide opportunities to better understand the dynamics of sedimentary systems. In this talk I will provide an overview on global plastic-pollution, microplastic as a new and unique sediment particle, and on microplastics in seafloor sediments.

The Halimeda algal bioherms of the Great Barrier Reef, Australia represent the largest living, actively accumulating Halimeda deposits worldwide. Following the Holocene post-glacial marine transgression, these bioherms kicked off the outer-shelf carbonate factory some 2000 years earlier than the nearby coral reefs. Recent multi-disciplinary work has revealed new insights into their surface geomorphology, subsurface architecture and depositional environment that may be of interest to those working on their fossil counterparts.

Based on a recent review of the literature a data base of absolute values of short term (<3my) Cretaceous sea level rises and falls has been created. This shows an overall amplitude range of 5 to >65m, organised in four broad trends. The potential of aquifer eustasy has been investigated using climate modelling which showed a maximum impact of 5 to 10 meters. This leaves Glacio-eustasy as the key driver for short term high magnitude sea level changes in the Cretaceous.