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Exercise 5. Selecting subcatalogs

CompiCat allows the user to make different searches of subcatalogs by time, location, and magnitude. The two simplest examples of searches are considered in the tasks below. For details on other optional possibilities see 7.3 Select subcatalog.

Task 1: Select subcatalog of earthquakes, which epicenters are located inside the triangle {(37 , -122.5); (37.75 , -121.5); (36.2 , -120.5)}.

1) Run CompiCat: Open the file ...\ecp\exercises\ex5select.csf.
2) Click Select button in the vertical Tools bar on the left.

Open Hypocenter tab and set the requested coordinates of the three vertices: Check on the box in its upper leftmost corner and make sure that other tabs for being checked off. In Hypocenter tab choose Polygon radio button and proceed by clicking Set vertices button to Set polygon vertices window. Change the default coordinates for those of the Task 1.

Click Apply.

The program displays the choice of search parameters and asks for confirmation. If the parameters are confirmed, the program runs the search and will report the actual number of records in the output subcatalog.

3) Click OK button and save the resulting subcatalog as ex5selected in the ...\work directory.

Task 2: Find out how many earthquakes from the catalog created in Task 1 did happen before the 1989 Loma Prieta earthquake (1989/10/18 00:04:15.2, M7.0) ? 

1) Select subcatalog of the events in request: Click Select button in the vertical Tools bar on the left. Open Date or Number tab to set the requested time limit. Check on the box in its upper leftmost corner and make sure that other tabs for being checked off. In Date or Number tab choose Date radio button and change the ending date to the requested one. Click Apply.

The program displays the choice of search parameters and asks for confirmation. If the parameters are confirmed, the program runs the search and will report the actual number of records in the output subcatalog. Thus, the task is completed.

2) Click Cancel to close the window.