Natural hazard natural hazards and anthropic processes. For example, groundwater abstraction may trigger groundwater-related subsidence. Effective hazard analysis in any given area (e.g., for the purposes of disaster risk reduction) should ideally include an examination of all relevant hazards and their interactions. To be of most use for risk reduction, hazard analysis should be extended to risk assessment wherein the vulnerability of the built environment to each of the hazards is taken into account. This step is well developed for seismic risk, where the possible effect of future earthquakes on structures and infrastructure is assessed, as well as for risk from extreme
Seismic metamaterial the electromagnetic energy is in effect directed around an object, or hole, and protecting buildings from seismic waves employs this same principle. Giant polymer-made split ring resonators combined with other metamaterials are designed to couple at the seismic wavelength. Concentric layers of this material would be stacked, each layer separated by an elastic medium. The design that worked is ten layers of six different materials, which can be easily deployed in building foundations. As of 2009, the project is still in the design stage. For seismic metamaterials to protect surface structures, the proposal includes a layered structure of metamaterials, separated