GeoSciMeg

When I first started at university studying science I thought there would never be any uncertainty in what the right answer was however, after three and a half years this is certainly not the case . Chris MacLeod’s seminar ‘New View of Seafloor Spreading – 50 years on’ perfectly demonstrates this. Certainly, in first year and on websites the uniform ‘layer cake’ structure to the oceanic crust is taught. A conceptual model has been created due to evidence from the MOHO and Ophiolites. The MOHO or Mohorovičić discontinuity is the boundary between the Earth’s mantle and crust and is much shallower under the oceans. An Ophiolite is a section of the oceanic crust that has been uplifted. Since only 10% of oceanic lithosphere has been studied in any detail comparing ophiolite structure to seismic imaging of oceanic crust reveals oceanic crust has a layered rock series very similar to the Ophiolite, creating this uniform ‘layer cake’ model thought to be true (Fig 1). Ocean crust is created...

There was a clear motivation behind the seminar I attended by Stephen Darby of the University of Southampton that focused on the Mekong Delta in Southern Vietnam (Fig 1). The area is being affected by climate change at a rapid rate, with predicted temperature increase of 1.5⁰C resulting in a 1.5-3m sea level rise, areas of low lying land such as the Mekong Delta are at a huge risk of submergence. Sedimentation is the only process that can offset this sea level increase and therefore the reason Stephen started his research journey. Figure 1 : Map of the Mekong Delta Unfortunately, there are two main reasons there is now a limited supply of sediment to the Mekong delta preventing this offset. Firstly, after fieldwork the team realised a huge amount of discharge and sediment arriving in the delta was related to when tropical cyclones were occurring. Using numerical modelling they were able to quantify that the cyclone attributed rainfall caused more impact than the...