La Habra Simulations on Titan

Overview

A series of simulations modelling the La Habra 5.1 event will be performed on ORNL Titan with in order to address these scientific and computational goals:

• Demonstrate that Hercules-GPU software is in production status and evaluate its performance versus the CPU version
• Evaluate goodness of fit for synthetic waveforms versus observed at 1.0 Hz, using Po Chen's updated CVM-S4 velocity model as the material properties source for the simulation.
• [Optionally] Validate the simulation results generated by Hercules-GPU and AWP-GPU

Solver Parameters

Parameter	Value	Notes
Frequency	1.0 Hz
Simulation Length	100 s
Delta T	0.005
Plane Output Resolution	250m
I/O Print Rate	every 10 steps
Station List	LH_stations.txt	Merged from En-Jui's 0.2Hz station list and Ricardo's CH master list
Software Version	Hercules-GPU commit c95f1ab017e5f93613a0e3e2c6b5a849eb4117ad	GPU codes, no frequency dependent Q

Simulation Box / Velocity Model

Parameter	Value	Notes
Dimensions (km)	180 x 135 x 61.875
Bounding Box (LL)	-119.288842 34.120549, -118.354016 35.061096, -116.846030 34.025873, -117.780976 33.096503
UCVM Version	13.9.0	No heterogeneities
Velocity Model Versions	CVM-S4, CVM-S4 v26	CVM-S5?
Miniumum Vs	200 m/s
Samples per wavelength	8
Hercules Etree	ch-cvms400-100-4hz-200ms.e, ch-cvms426-223-4hz-200ms.e	CVM-S5 etree?

Sources

The simulation will be repeated for two point sources and one extended source.

Point Source Parameters

Parameter	Value	Notes
Event Name	La Habra
Origin Time	2014/03/29 04:09:42.97	Source: En-Jui
Origin Location	-117.930; 33.922; 5.0km	Source: En-Jui
Strike/Dip/Rake 1	134/55/155	Source: En-Jui, initial
Strike/Dip/Rake 2	239/70/38	Source: En-Jui, based on review of aftershock sequence
Rise Time	0.75 s

SRC Format La Habra Source

• MAGNITUDE = 5.12
• FAULT_LENGTH = 5.0
• FAULT_WIDTH = 2.25
• DEPTH_TO_TOP = 4.7125
• STRIKE = 239
• RAKE = 38
• DIP = 79 (typo? should be 70?)
• LAT_TOP_CENTER = 33.9119
• LON_TOP_CENTER = -117.940
• HYPO_ALONG_STK = 0.0
• HYPO_DOWN_DIP = 1.125
• DLEN = 0.1
• DWID = 0.1

Volume

The four corners are:

• -119.288842 34.120549
• -118.354016 35.061096
• -116.846030 34.025873
• -117.780976 33.096503

And the box has size

• 180,000 m x 135,000 m x 61,875 m

Runs

Hercules Runs

Run Number	Etree	Source	Notes
1	ch-cvms400-100-4hz-200ms.e	point-ricardo-134-55-155
2	ch-cvms426-223-4hz-200ms.e	point-ricardo-134-55-155
3	ch-cvms400-100-4hz-200ms.e	point-ricardo-239-70-38
4	ch-cvms426-223-4hz-200ms.e	point-ricardo-239-70-38
5	ch-cvms400-100-4hz-200ms.e	extended-ricardo
6	ch-cvms426-223-4hz-200ms.e	extended-ricardo

BBP Run

• SRC for this event

• SRF Image
• SRF for this SRC

La Habra Earthquake Observations

• Center for Strong Motion Engineering Data Center

La Habra References

• SCSN La Habra Event Summary
• SCSN La Habra Moment Tensor Solution

References

1. Bielak, J., H. Karaoglu, and R. Taborda, 2011. Memory-efficient displacement-based internal friction for wave propagation simulation, Geophysics, 76(6):T131-T145.
2. Taborda, R., Lopez, J., Karaoglu, H., Urbanic, J., and Bielak, J. (2010). Speeding up finite element wave propagation for large-scale earthquake simulations. Technical Report CMU-PDL-10-109, Carnegie Mellon University, Parallel Data Lab.
3. Tu, T., Yu, H., Ramírez-Guzmán, L., Bielak, J., Ghattas, O., Ma, K.-L., & O’Hallaron, D.R., 2006. From mesh generation to scientific visualization: an end-to-end approach to parallel supercomputing, in Proceedings of the 2006 ACM/IEEE International Conference for High Performance Computing, Networking, Storage and Analysis, p. 15, IEEE Computer Society, Tampa, Florida.