Subject: Why GEM? Resent-Date: Thu, 23 Dec 1999 10:42:31 -0500 Resent-From: Geoffrey Fox Resent-To: p_gcf@npac.syr.edu Date: Thu, 23 Dec 1999 07:32:14 -0800 From: "Kenneth J. Hurst" To: Geoffrey Fox CC: andrea@cobra.jpl.nasa.gov, John Rundle Geoffrey - Here are the words I read at the GEM meeting in SF. Ken A model, to the extent that it is realistic, is useful in guiding our intuition about the earthquake process, and suggesting new measurements or lines of inquiry. Making such a model realistic requires many different types of data and expertise. A partial list of data types might include: paleoseismic data, GPS data, leveling data, strain data, strong motion data, regional seismicity data, downhole seismic data, multi-channel seismic data, interferometric synthetic aperture radar (InSAR) data, laboratory measurements of physical and mechanical properties of various rocks, 3-D geologic structure, gravity data, heat flow data, magneto-telluric data, hydrology data, and ocean tide data (to constrain coastal uplift). There are productive scientists who have built or are building entire careers on each individual type of data mentioned above. No individual scientist at this time has access to complete collections of all these data types, nor the detailed expertise which would be required to use all these data types in a computational model. Consequently, either the models we will develop will be based on some subset of the data, or we must develop an environment in which people can collaborate to construct models which span multiple data sets and which can then be embellished by other investigators. To maximise the utility of any given data set, we must keep the people who collect, use, and care about the data as the ones who archive it and make it available. The people or community who "own" the data should be the ones who are responsible for curating the data collection. This implies that the data archives we will need to access are necessarily distributed in nature. Thus, we need an environment which will allow easy collaboration and access to diverse data sets. Further, the most rapid progress will be made in an environment which not only allows easy collaboration and access to diverse data sets, but also facilitates easy comparison and exchange of models. Ken Hurst Mail Stop 238-600 voice: 818-354-6637 Jet Propulsion Lab / Caltech FAX: 818-393-4965 Pasadena, CA 91109 hurst@cobra.jpl.nasa.gov