The next DIAS seminar will be held at 16.00 at No 5, Merrion Square, where Dr. Sean McKenna from IBM Research Laboratory, Ireland will present the following talk: Modelling groundwater flow and transport in strongly heterogeneous formations.


Transmissivity in heterogeneous and fractured media can range over many orders of magnitude. Predictive modelling within probabilistic risk assessment calculations requires numerical representations of these heterogeneous formations. Here, an example problem for a geologic repository is used to demonstrate the application of continuous and indicator geostatistics to create a set of seed fields conditioned to a complex geologic conceptual model and local measurements of transmissivity and storativity. Inverse parameter estimation with pilot points is used to modify these seed fields to condition them to observations of hydraulic pressure including the results of over 20 years of hydraulic testing. The resulting fields are used as input to an advective transport model. In order to quantify uncertainty in the transport predictions, multiple seed fields are run through the computationally expensive inverse calibration process. Several approaches to decreasing this computational load through decomposition of the parameters into a solution space and a null-space are examined and the impacts of each approach on the calibration and the advective travel time are quantified.


Sean McKenna is a Senior Research Manager at the IBM Research Laboratory in Dublin, Ireland. He leads a department of scientists and engineers focused on applying cognitive computing techniques to solve problems in natural resources management, renewable energy supplies and infrastructure systems. Solution techniques include computational and data-driven approaches to take advantage of increasing amounts of sensor data in combination with physical models. Prior to joining IBM in November of 2012, Dr. McKenna was a Senior Scientist in the Geosciences Research and Development Dept. at Sandia National Laboratories in Albuquerque, New Mexico, USA. While at Sandia, he was responsible for applied research in subsurface flow and transport for applications in spent fuel repositories, CO2 sequestration and water security. Dr. McKenna has held adjunct, or visiting, faculty positions at the University of New Mexico, National University of Singapore (NUS), the University of Texas at Austin and New Mexico Tech. He has a BA from Carleton College, an MS from the University of Nevada, Reno and a PhD from the Colorado School of Mines. Dr. McKenna served as the 2016 International Association of Mathematical Geosciences (IAMG) Distinguished Lecturer.

Venue: 16.00 at DIAS, No 5, Merrion Square, Dublin 2