JISCMail - GEO-TECTONICS Archives

I’ve recently revised the Global CMT viewer (webmap) that I had made a few years ago and posted to the list. Thanks to improvements in the readily-available technology, lots of help from a group of programmers, and incremental improvements in my own abilities, the GCMT Viewer (gcmt-viewer.earth-analysis.com) is now pretty fast, gets new CMTs every 4 hours, and won’t even instantly crash your browser anymore.

I’ve also updated the imagery used, and color coded the beachballs so that the dark part (T quadrant) is based on depth. Dark purple is 10 km, and the color transitions logarithmically w/ depth to bright yellow at 700 km depth. This is particularly helpful in active margins, distinguishing crustal from deeper slab events when looking for inboard deformation (I’m looking at you, Bolivia!). I’ve also added a filtering algorithm so that small earthquakes in high-EQ-density regions don’t show up at low zoom levels. And you can click on an event to see its date, magnitude and depth.

Unlike the previous iteration, this version is a real webapp with a dedicated server and database backend. Because this is a hobby project, I went with a cheap server instance. It’s single-core and I have no idea how responsive it is when all 26 people on earth who like to browse focal mechanisms on a map do so at once. But please try it, and if it’s unresponsive, particularly at more zoomed in levels, let me know! I believe the speed at which the image tiles load is connection based, but if panning/zooming is annoyingly slow or other problems occur, I would like to be informed. I’m happy to pay a little more for a better server if people who want to use this are having problems.

Future improvements: I will be updating the faults that are shown over time; I’m working for the GEM Foundation making a global active fault database, and I will be periodically updating the faults as new regions get integrated, and hopefully at least color coding by fault type (maybe changing line thickness with slip rate or something too) if I can figure out the javascript. I would also really love to find some base imagery that shows bathymetry pretty well. I will one day have a depth scale, and potentially some tools for filtering by depth, magnitude and date.

Also, for anyone interested in making some open-source geology web applications: I’ve started a group with some non-scientist programmer friends called SegFaults; we’ve made this version together. The next project is making a web version of my fault slip rate calculator. However, though individuals are somewhat time-limited, I’m finding that there are a fair amount of programmers who like building stuff and learning new technologies but aren’t overflowing with project ideas and are looking for side-project collaborations with scientists who have web programming needs. If you want to be involved in any capacity, please let me know. All our code is at https://github.com/seg-faults. Right now it’s like 5 people but it could probably grow, especially with scientists who can help code.