TY - JOUR
T1 - Aseismic deformation across the Hilina fault system, Hawaii, revealed by wavelet analysis of InSAR and GPS time series
AU - Shirzaei, Manoochehr
AU - Bürgmann, R.
AU - Foster, J.
AU - Walter, T. R.
AU - Brooks, B. A.
N1 - Funding Information:
Thanks to Mike Poland for providing the high-resolution digital elevation model and for valuable discussions. The interferograms used in this study were generated using the GMTSAR software ( Sandwell et al., 2011 ). Radar data were provided by the European Space Agency under project C1P-9539 . The Kılauea and Mauna Loa GPS networks are supported by grants from the USGS , NSF , and NASA and operated in collaboration by the USGS, Stanford University and the Pacific GPS Facility at the University of Hawaii.
PY - 2013/8/5
Y1 - 2013/8/5
N2 - The Hilina Fault System (HFS) is located on the south flank of Kilauea volcano and is thought to represent the surface expression of an unstable edifice sector that is active during seismic events such as the 1975 Kalapana earthquake. Despite its potential for hazardous landsliding and associated tsunamis, no fault activity has yet been detected by means of modern geodetic methods, since the 1975 earthquake. We present evidence from individual SAR interferograms, as well as cluster analysis and wavelet analysis of GPS and InSAR time series, which suggest an inferred differential motion at HFS. To investigate the effect of atmospheric delay on the observed differential motion, we implement a statistical approach using wavelet transforms. We jointly analyze InSAR and continuous GPS deformation data from 2003 to 2010, to estimate the likelihood that the subtle time-dependent deformation signal about the HFS scarps is not associated with the atmospheric delay. This integrated analysis reveals localized deformation components in the InSAR deformation time series that are superimposed on the coherent motion of Kilauea's south flank. The statistical test suggests that at 95% confidence level, the identified differential deformation at HFS is not due to atmospheric artifacts. Since no significant shallow seismicity is observed over the study period, we suggest that this deformation occurred aseismically.
AB - The Hilina Fault System (HFS) is located on the south flank of Kilauea volcano and is thought to represent the surface expression of an unstable edifice sector that is active during seismic events such as the 1975 Kalapana earthquake. Despite its potential for hazardous landsliding and associated tsunamis, no fault activity has yet been detected by means of modern geodetic methods, since the 1975 earthquake. We present evidence from individual SAR interferograms, as well as cluster analysis and wavelet analysis of GPS and InSAR time series, which suggest an inferred differential motion at HFS. To investigate the effect of atmospheric delay on the observed differential motion, we implement a statistical approach using wavelet transforms. We jointly analyze InSAR and continuous GPS deformation data from 2003 to 2010, to estimate the likelihood that the subtle time-dependent deformation signal about the HFS scarps is not associated with the atmospheric delay. This integrated analysis reveals localized deformation components in the InSAR deformation time series that are superimposed on the coherent motion of Kilauea's south flank. The statistical test suggests that at 95% confidence level, the identified differential deformation at HFS is not due to atmospheric artifacts. Since no significant shallow seismicity is observed over the study period, we suggest that this deformation occurred aseismically.
KW - Cluster analysis
KW - Hawaii
KW - InSAR
KW - Landslide
KW - Wavelet analysis
UR - http://www.scopus.com/inward/record.url?scp=84883055913&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84883055913&partnerID=8YFLogxK
U2 - 10.1016/j.epsl.2013.06.011
DO - 10.1016/j.epsl.2013.06.011
M3 - Article
AN - SCOPUS:84883055913
SN - 0012-821X
VL - 376
SP - 12
EP - 19
JO - Earth and Planetary Science Letters
JF - Earth and Planetary Science Letters
ER -