The latest version of algorithm was run for 26 earthquakes, and results were simulated as if in real time. The key metrics used for the benchmark were:
- How quickly the hypocenter is being estimated?
- Offset between estimated and true hypocenter
Offset distance vs. time after earthquake was plotted for all the events, and most of them looked like these:
Note that dive in offset distance starts within seconds of earthquake occurring. This validates the utility of the Brute Force Hypocenter estimation model. The table below summarizes these results for few events for CSN sensors:
Name
|
Magnitude
|
Offset (km)
|
Time After event (s)
|
La Canada
|
1.7
|
48.0360954
|
1
|
Fontana 3
|
4.4
|
10.9443251
|
5
|
Westwood
|
4.4
|
17.2685902
|
6
|
La Habra
|
5.1
|
17.5934921
|
7
|
Average
|
3.9
|
23.47
|
4.75
|
And another summarizes results for CISN Sensors:
Name
|
Magnitude
|
Offset (km)
|
Time After event (s)
|
Altadena
|
2.1
|
18.6
|
17
|
Brawley
|
5.5
|
2.7
|
11
|
Beverly Hills
|
3.2
|
14.3
|
12
|
Newhall 2
|
3.9
|
5.4
|
11
|
Lennox
|
2.4
|
8.8
|
12
|
Manhattan Beach
|
3.3
|
5.4
|
11
|
San Fernando
|
2.4
|
5.4
|
13
|
Monterey Park
|
1.7
|
84.9
|
13
|
North Hollywood 2
|
2.6
|
10.9
|
12
|
Rancho Cucamonga
|
1.9
|
12.0
|
11
|
Anza
|
4.7
|
2.0
|
12
|
Anza 2
|
3.4
|
23.9
|
12
|
Fontana 2
|
2
|
6.1
|
11
|
Los Angeles
|
2.8
|
6.6
|
11
|
Marina del Rey
|
3.2
|
3.6
|
10
|
Marina del Rey 2
|
2.8
|
12.9
|
11
|
Meiners Oaks
|
3.6
|
8.6
|
13
|
Santa Barbara Channel
|
4.9
|
47.6
|
15
|
Rancho Palos Verdes
|
2.9
|
6.2
|
14
|
Weldon
|
4.3
|
17.4
|
14
|
Weldon 2
|
4.2
|
16.6
|
18
|
La Verne
|
3.7
|
27.1
|
11
|
Joshua Tree
|
4.2
|
19.3
|
11
|
Fontana 3
|
4.4
|
9.5
|
9
|
Westwood
|
4.4
|
5.7
|
10
|
La Habra
|
5.1
|
15.3
|
10
|
Average
|
3.44
|
15.3
|
12.1
|
For these 26 events (CISN, see appendix) we see that we can estimate hypocenter with average offset of 15.3 Km with on an average 12.1 seconds after the earthquake. This is very close to 10 seconds that we aimed at.
For CSN sensors, the same model was able estimate hypocenters with average offset of 24km and on an average 5 seconds after the event. This was expected since CSN sensors are denser, hence better timing. On the other hand, CISN sensors are less dense, but have superior quality, hence better offset.
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