Electrical Resistivity Tomography (ERT) Geophysics

What is ERT? Electrical Resistivity Tomography (ERT) is a geophysical technique that uses electrical currents to image the subsurface. Don't let the name intimidate you, let's break it down: Electrical: an electrical field is passed through the ground (and measured along the way) Resistivity: we are interested in knowing how different materials "resist" that current … Continue reading Electrical Resistivity Tomography (ERT) Geophysics

Creeping Hazards: Towards a Framework for Transformability and Resilience

Geohazards have generally been understood and defined as events that take place on short human timescales, from milliseconds to a several months. However, both human- and naturally-induced events can develop and occur over the course of several years or longer. “Creeping hazards”—a term used as early as 1979 and referenced, though sparingly, in subsequent works—are a subset of events that exhibit the characteristics of geohazards (i.e., in terms of vulnerability, risk, and exposure). Distinct, but related to, “slow-onset” disasters, creeping hazards reflect permanent changes to a system. For example, although drought is often included as an example of such a hazard, drought is better understood as a slow-onset disaster. Better examples of a creeping hazard as defined here include aquifer depletion (and associated land subsidence), desertification, land degradation, certain hazards associated with climate change, and soil creep.