Aberdeen Evening Lecture: August 2019

Open to all PESGB Members. PESGB Members do not need to register to attend.

Food and drink served from 6:00pm, lecture starts at 6:30pm

Since the start of the millennium, there has been a quiet revolution in the Earth Sciences. For 200 years, from the time that William Smith published his ground breaking map, up until the turn of the millennium, field data were collected on paper maps using pencils and rotering pens. Structural measurements were made with a compass clinometer and lithology and mineralogy were manually interpreted using a hand lens and acid. Less than 20 years later, outcrops are routinely digitised using data collected by laser scanners and drones. Lithology can be remotely mapped using hyperspectral imagery and outcrop interpretation, and even fieldtrips can be undertaken from the desktop computer. The Virtual Geoscience revolution has fundamentally changed the way in which reservoir analogue studies are undertaken and the way in which outcrop data are delivered to end users. These advances in geological fieldwork are also being applied outside the oil industry and away from reservoir analogue studies. As the acquisition of Virtual Geological Outcrops (VOs) has become more routine, the earth science community is continually inventing new ways to utilise these data. In this contribution we present a study which illustrate the novel application of these methods, which we believe have far-reaching implications for disaster mitigation.

Volcanos represent a continuous and well-known natural hazard to millions of people around the world. Volcanic monitoring is required to predict the exact timing of eruptions in order to facilitate evacuation of nearby settlements. This monitoring typically involves the placement of a network of seismic recording devices, as well as other instruments, across the volcano, a process which is expansive and potentially hazardous. In addition to seismic monitoring, satellite altimetry is sometimes used to record small scale changes in the topography of the volcano which may represent a prelude to an eruption. In a recent test study preliminary field trials were undertaken on Stromboli, an active volcanic island off the coast of Sicily. These trails involved flying two UAVs across the crater of the volcano. The first was used to record a set of over 1000 regular (RGB) photographs which were used to build a photogrammetric DEM of the crater with a vertical and horizontal resolution of 0.1m. The second UAV was fitted with a FLIR Infer Red was used to acquire a comparable set of thermal images. Ground control points (burning torches) were measured with a dGPS to allow the two 3D models to be accurately aligned. The IR imagery was then draped over the DEM to produce the world’s first 3D thermal model of the volcano. This model has the advantage of being able to image the vent which is commonly shrouded in dust and steam and also highlighted a number of thermal anomalies on the flanks of the volcano which are interpreted to be related to lava flows from the last major eruption in August 2014.

In the future, repeat surveys could be used to monitor subtle changes in both the surface topography and heat flow of the volcano, providing a low cost, low impact and safe monitoring program.