West--Fissure- and Atacama-Fault Seismic Network, Northern Chile
We installed a temporary seismic network that consists of two sub-nets in order to monitor micro-seismicity at the Atacama and West Fissure Fault System in Northern Chile. The net around the West Fissure Fault System was operated during the period between November 2005 and November 2009 and again from March 2010 until March 2012. The net around the Atacama Fault System recorded from March 2010 to March 2012. Both sub-nets consist of surface stations with 3-component seismometers of type Mark L4-1Hz. The data recording is continuous at a sample rate of 200Hz, with a few time intervals recorded at only 100 Hz. Data loggers are Earth Data PR-24. Power is supplied by 60W solar panels with a 12V battery backup. The seismic monitoring system around the West Fissure Fault System covers an area of approx. 100 times 80 km at elevations between 3000m and 5000m a.s.l. and consists of an average of 11 seismic stations. The seismic monitoring system around the Atacama Fault System covers an area of approx. 40 times 30km around the Salar Grande salt lake at elevations between 600m and 1000m a.s.l. and consists of 10 surface stations. The network recorded waveforms of over 7,000 weak seismic events. These microearthquakes witness a variety of seismogenic processes such as deformation due to tectonic stress, fluid migration or metamorphic mineral reactions. They occur along major fault zones mapped at the surface, in the continental crust, at the interface between the South American and the Nazca plate and in the oceanic crust and mantle.
* Description is taken from seismic metadata, and may not match the preferred title for citations.
Bloch, W.; Kummerow, J.; Salazar, P.; Wigger, P.; Shapiro, S. A. (2014). High-resolution image of the North Chilean subduction zone: seismicity, reflectivity and fluids. Geophysical Journal International, 197, 1744-1749. doi:10.1093/gji/ggu084
Salazar, P. (2011). The upper crustal microseismicity image from the North Chilean subduction zone: implications for tectonics and fluid migration. Ph.D. thesis, Freie Universität Berlin.