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232.4.3 New Madrid Seismic RegionData on 219 earthquakes in the New Madrid seismic region were obtained fromthe Center for Earthquake Research and Information (CERI) World Wide Website http://samwise.ceri.memphis.edu. We have included all earthquakes in theNew Madrid catalog from 1974 to 1992 with a magnitude of 2.5 and above. Thistime period was chosen because the data collection methods were consistent; dataprior to this period are available but become sparser and less reliable as one goesback in time. The New Madrid region extends from Illinois to Arkansas: latitude35 to 38 and longitude -91 to -88. These data are displayed in Figure 2.10, andthe BIC results are shown in Table 2.3. Figures 2.11 to 2.14 show each step of ourprocess; the final result (Figure 2.14) corresponds to the parameters which yieldthe maximum BIC value (3 features, each with 10 degrees of freedom).This example illustrates some strengths and limitations of our method. We cansee in Figure 2.11 that the most striking features in this dataset are a combinationof lines and blobs. While our method does a good job of picking out the curvilinearfeatures, blobs are not very well modeled by curves, causing the rather awkwardlooking result for the rightmost feature.