Fault Model in 3-D

Here are a couple maps that I put together to help me visualize a potential fault that may have ruptured in La Habra on 2014/03/29. This is a very quick, coarse, and precursory look. Others have better tools and will create better visualizations that may actually be quantitative. These maps are qualitative at best.

I took the USGS earthquake database (arguably, there are better ones) and plotted these epicenters. Then i created a raster surface based on an Inverse Distance Weighted relation, for the depths of these earthquakes. I did several different versions, each with varying levels of adherence to adjacent depth values. Below are two different realizations of the same fault surface.

This one uses a common elevation-topography color ramp (green is low elevation, brown mtns are topped in white for higher elevation).

Here is the moment tensor as a reminder.

This one uses a novel color ramp with multiple “maxima” in value (brightness, in the form of yellow hue). These act like contours, but are distributed across the surface (which reveals something about the slope of the surface, without an additional slope map. These yellow regions allow one to visually move across the surface to see how it changes orientation in a continuous, or discontinuous manner. An added bonus is this map could be framed as modern art (?). Though the modeled surface is pretty noisy from an analytical perspective.

There are many assumptions that could be evaluated to filter these input data better. But the big picture is interesting. It looks like this is a ne striking, nw dipping fault, though it is not planar.

Category(s): College Redwoods, earthquake, education, geology, plate tectonics, San Andreas

One Response in another blog/article

  1. […] house were very jittery for each aftershock. I have posted about this earthquake before here, here, here, and here. The Southern Earthquake Research Center produced some educational material about this […]

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