Engineering Geology - Geohazards and Adverse Geo-conditions

Geohazards and Adverse Geo-conditions

Typical geologic hazards or other adverse conditions evaluated and mitigated by an engineering geologist include:

• fault rupture on seismically active faults ;
• seismic and earthquake hazards (ground shaking, liquefaction, lurching, lateral spreading, tsunami and seiche events);
• landslide, mudflow, rockfall, debris flow, and avalanche hazards ;
• unstable slopes and slope stability;
• erosion;
• slaking and heave of geologic formations, such as frost heaving;
• ground subsidence (such as due to ground water withdrawal, sinkhole collapse, cave collapse, decomposition of organic soils, and tectonic movement);
• volcanic hazards (volcanic eruptions, hot springs, pyroclastic flows, debris flow, debris avalanche, gas emissions, volcanic earthquakes);
• non-rippable or marginally rippable rock requiring heavy ripping or blasting;
• weak and collapsible soils, foundation bearing failures;
• shallow ground water/seepage; and
• other types of geologic constraints.

An engineering geologist or geophysicist may be called upon to evaluate the excavatability (i.e. rippability) of earth (rock) materials to assess the need for pre-blasting during earthwork construction, as well as associated impacts due to vibration during blasting on projects.