USA Today/USGS Maps of Chilean Earthquake Aftershocks Use Thematics Improperly

The map of aftershocks from the Chilean earthquake last week reveals the incredible number of strong quakes that continue to jolt the region. Unfortunately, maps produced by the USGS and picked up by USA Today are inappropriately thematicized. The map shows the location of aftershocks marked by large circular symbols that are color-coded according to their most recent occurrence. Those that have been felt within the last hour are red; within the last day are orange; and those within the last week are yellow. It is a totally confusing way to map mainly because the idea should be to recognize both the location and severity. As they are portrayed, the symbols are all the same size and completely obscure most of the information.

Here's my suggestion: Keep the color-coding but use a graduated symbol to represent the aftershock's magnitude. this would help cut down on what is now a very cluttered map. And it would have been a nice addition if it showed the major fault lines as well.

Comments

jluch82 said…
The KML file the USGS made was supposed to be seen in Google Earth, and the size of size of the points do change with the Magnitude of the earthquakes. This is a bad use of the data by USA Today, it is not USGS's fault.

see this map as a more appropriate example: http://www.mapserving.com/gmap/g1/?mid=5207
April 5, 2010 at 7:51 AM
Post a Comment

Popular posts from this blog

USAToday Looks at Bleak Jobs Growth Outlook for 2010

The job outlook for 2010 doesn't look very rosy according to a map published by USAToday . Though the prospect for job growth will rebound in some areas, most states will continue to so slow or no growth. Hardest hit continue to be Florida, the upper Midwest, and Nevada. The bright spots include the corridor of Texas, Colorado, Wyoming, Idaho and Washington State where jobs in energy and technology are likely to be found. By metro area, look toward Huntville, Alabama, my current hometown, where jobs gowth is expected to be the highest in the country with a projected growth of 2.9%. This high tech mecca will see job growth due to Base Realignment and Closure (BRAC) and the supporting jobs that will move into the region.
Read more

Chinese Investments in Raw Materials Mapped by Forbes.com

Image
Forbes.com created a graduated symbol map (see thumbnail at right) of the investments that the Chinese have made in various raw material sectors such as energy, minerals, and transportation. The interactive map illustrates: the accelerated growth in the number of investments made over the past five years the size of each investment the industry sector Tool tips appear as you hover the cursor over each symbol that shows: the investor the amount of the investment when the investment was made the industry sector What is striking about the portrayal of the data is not the size so much as the rapidity with which the investments have been made over just the last two years. If you watch the animated sequence, you will see how many of the investments were accomplished just recently. The feeding frenzy for raw materials is what is driving infrastructure growth throughout the Mainland.
Read more

National Media Scrambles with Maps of Haiti

As the geospatial community rushes into support rescue efforts with as much detail as possible, the national media has produced a variety of different maps to help tell the story. Wall Street Journal - The WSJ has produced a series of three excellent, interactive maps : LATEST UPDATES: a thematic map of estimated damages by block and the locations of key places like the National Palace or the UN building as well as tent camps. BEFORE AND AFTER: a satellite image base with point locations of major structures where you can view photos of before and after shots. TECTONICS: A population map overlayed with a map of the Gonave microplate and the location of the earthquake with concentric zone showing quake intensity. USA Today - Map of earthquakes with more than 1000 deaths ; provides a bit of history of and the location of major crustal plates that gives the reader a lession in plate tectonics New York Times - Map showing magnitude of the disaster and details on the impact to d
Read more