Ground rotations : what do they tell us , that we did not know before ?
نویسندگان
چکیده
Currently there are two types of measurements that are routinely used to monitor global and regional seismic wave fields. Standard inertial seismometers measure three components of translational ground displacement (velocity, acceleration) and form the basis for monitoring seismic activity and ground motion. The second type aims at measuring the deformation of the Earth (strains). It has been noted for decades (Aki and Richards, 2002, and previous edition) that there is a third type of measurement that is needed in seismology and geodesy in order to fully describe the motion at a given point, namely the measurement of ground rotation. The three components of seismically induced rotation have been extremely difficult to measure, primarily because previous devices did not provide the required sensitivity to observe rotations in a wide frequency band and distance range.
منابع مشابه
Welcome to virosphere
Viruses may seem alien, but they are the most abundant and, arguably, the most important organisms on Earth. They are found just about everywhere, from oceans and forests to the people around you and, of course, in and on you as well. This world of strange, quasi-living things has been dubbed the virosphere, and it is a mysterious one – we know less about viruses than any other life form. But t...
متن کاملDiagnostic and therapeutic challenges for dermatologists: What shall we do when we don’t know what to do?
What shall we do when we have done everything we could for the diagnosis and treatment of a patient, but were not successful? What shall we do when there is no definite treatment for a patient? What shall we do when we have no diagnosis or treatment for a patient? Some useful suggestions are presented here to get rid of these situations.
متن کاملEvaluation of an evaluation
Introduction. Evaluation is a systematic way to improve and make more effective actions that involves procedures which are useful, feasible, ethical, and accurate. Common questions in all evaluations are: do all part of program do well and effective? What is the good functioning? Why the program or its parts do not work well? What are the effects and consequences of the program? Is this progra...
متن کامل