Exploration Insights September 2020 - Page 14

14 | Halliburton Landmark New Frontiers in Plate Boundaries by: Jean-Christophe Wrobel-Daveau, Bruce Eglington and Graeme Nicoll Crustal dynamics showing earthquakes, plate boundaries, and volcanoes. Image from https://svs.gsfc.nasa.gov/155 with credit to NASA/Goddard Space Flight Ce Research Project (GCRP), National Oceanic and Atmosphere Administration (NOAA), United States Geological Survey, National Science Foundation (NSF), Defen (DMA), New York Film and Animation Company, Silicon Graphics, Inc. (SGI), Hughes STX Corporation. Given a plate tectonic model is meant to be a singular representation of what the Earth looked like back through geological time, one might ask, why are so many different models available, and which one should I use? In order to answer these questions, it is useful to understand the genealogy of the different plate tectonic models, what data underpin them, what methods and techniques are used to construct and update them, and what uncertainties are involved. We will go on to consider how the scope and complexity of these models went hand-in-hand with growing computational power over the last 60 years. In order to compare and contrast the variety of plate tectonic models that exist today, we need to set out the main difference between plate tectonics and continental drift models, and consider the importance of plate tectonic boundaries. This story builds on discussions in previous editions of the Exploration Insights magazine. Recent articles discussed the evolution of the theory of plate tectonics and its importance to all geological concepts (Wrobel-Daveau and Nicoll, 2019), and how in the modern age, plate tectonic models are an important tool for use in natural resource exploration workflows (Lang et al., 2020). PLATE TECTONIC MODEL GENEALOGY The first attempts at reconstructing the paleoposition of continental land masses were hand-drawn as far back as the 17 th century by Dutch map makers, and later in the 20 th century by Alfred Wegner and Boris Choubert (Kornprobst et al., 2018). However, these were really just singular snapshots of often poorly constrained geological times, and are more akin to paleogeographic maps (Figure 1). Indeed, they lacked the understanding of geodynamic processes, such as the absolute and relative motion of plates on a sphere, the driving mechanisms behind plate motion, and the existence of plate limits.