+ Resolve Article
+ Follow Us
Follow on FacebookFollow on Facebook
Follow on TwitterFollow on Twitter

+ Translate
+ Subscribe to Site Feed
GeoScience Most Shared ContentMost Shared Content

About the use of coda wave signals to estimate local site amplification factors

, : About the use of coda wave signals to estimate local site amplification factors. Pages 523-530 1998

Several methods were developed to estimate the local site amplifications from weak or moderate size earthquake recordings. Most techniques are based on the calculation of spectral ratios (classical spectral ratio, generalized inversion, Phillips and Aki's Coda wave method, 1986) using either S-wave signals, Coda wave signals or a complete recording (P-waves, S-waves and Coda). The differences due to the different signal contributions are not very well understood. In several studies important variations of the estimated amplifications are obtained only due to different choices of the analyzed windows of the same data. In this work, we discuss the differences between estimates based on S-wave and Coda signals depending on the method. Taking into account different window contents and methods, we show that the results of various studies presented in the literature are more consistent than it actually appears. As a general trend, the estimates based on the Coda wave give higher estimates of the amplification level than using the classical spectral ratio technique applied on the S-wave signal. The estimates obtained using the classical spectral ratio technique from the Coda wave signals of only one window overestimate systematically the local site amplification while the mean-estimates obtained from several moving windows using Phillips and Aki's Coda wave method are in better accordance with the classical estimates using one S-wave window. The correct choice of the data window is consequently a necessary basis for every reliable estimation of local site amplification. Our statements are confirmed by a direct comparison of estimates obtained from different methods (classical spectral ratio technique using S-wave and Coda wave signals, Phillips and Aki's Coda wave method) on two data sets: EURO-SEISTEST (test-site near Thessaloniki, Greece) and Borrego Mountains array (California).


Other references

Khokhlov, G.G., 1985: Characteristics of the epidemic process in influenza A in 1978-1982. Voprosy Virusologii 30(3): 364-366

Crowe, M., 2015: Biochemical And Tumorigenic Effects Of Redox Modification Of Ras-G12c By Nitric Oxide. The Ras family of small GTPases cycle between an inactive, GDP-bound state and an active, GTP-bound state. When bound to GTP, Ras engages and activates a number of effectors that mediate proliferative and survival signals. Ras is mutated in over 3...

Latha, N.; Naga Siva Rao, J.; Raghunathan, R.; Divya, G.; Lakshmi, S., 2014: (4'-Acet-yloxy-1,3,1'-trioxo-1,3,4,4a,4b,5,6,7,9,9a-deca-hydro-spiro-[indene-2,9'-pyrano[4,3-a]pyrrolizin]-3'-yl)methyl acetate. In the title compound, C23H23NO8, the dihedral angle between the five- and six-membered rings of the indene-dione moiety is 3.09 (13)°. The mean plane of the five-membered ring (which has a flat envelope conformation with the spiro C atom as th...

Tuddenham, R.D.; Macbride, P.; Zahn, V., 1958: The influence of the sex composition of a group upon yielding to a distorted norm. Susceptibility of college students to yielding to a grossly distorted norm was tested with men and women working in mixed groups of 5 making visual judgments, specifically estimating line lengths. It was hypothesized that for men the tendency to y...

Aagaard, J.; Amdrup, E.; Aminoff, C.; Sørensen, F.H., 1983: A predictor analysis of clinical assessment of outcome among patients operated on for duodenal ulcer. A 1-year prospective study. During a period of 1 year, data concerning life events, non-specific psychological symptoms, individual social history, and ulcer history were obtained for consecutive cases of patients about to have elective surgical treatment for duodenal ulcer....

Peel J.; Porter N.; Lowry J.; Winfield D.A., 1989: Reactivity of new myeloid workshop antibodies with normal and leukemic leukocytes. Tissue Antigens 33(2): 242

Dong, W.; Chen, H.; Yang, X.; Guo, L.; Hui, G., 2010: Treatment of intracerebral haemorrhage in rats with intraventricular transplantation of human amniotic epithelial cells. We explored the effects on brain oedema and neurological functional recovery after transplantation of hAECs (human amniotic epithelial cells) into the lateral ventricle of rats with ICH (intracerebral haemorrhage). hAECs were isolated from human t...

Burklew M.A., 1971: Extraction of glycogen from oysters. Florida Department of Natural Resources Marine Research Laboratory Leaflet Series PART(4): NO

Mitchell, JC., 1989: Summary of business conducted at the Annual Meeting of the Herpetologists League. Canterbury, England 10-18 September 1989. Herpetologica, 454: 479-482

Golding, J.P.; Zammit, P.S.; Tonge, D.A., 1992: Effects of freezing a segment of peripheral nerve on subsequent protein release and axonal regeneration in the frog. Previous studies in frogs have shown that axons from the proximal stump of a cut nerve will grow toward the distal stump, possibly in response to diffusible trophic factors produced by cells of the nerve sheath. In the present experiments, the syn...