000018518 001__ 18518
000018518 005__ 20170118182226.0
000018518 04107 $$aeng
000018518 046__ $$k2017-01-09
000018518 100__ $$aYushi, Wang
000018518 24500 $$aApplication of H/V Method in a Small-Scale Basin

000018518 24630 $$n16.$$pProceedings of the 16th World Conference on Earthquake Engineering
000018518 260__ $$b
000018518 506__ $$arestricted
000018518 520__ $$2eng$$aNakamura method, i.e. H/V method of ambient tremor, is applied in a small-scaled lacustrine sedimentary basin in Northeast China, which is suspected to be a meteorite impact crater covered by soft and deep lacustrine deposit layers. The ambient tremor was observed for hours at 50 points in the basin, and then horizontal Fourier amplitudes to vertical Fourier amplitudes ratios, i.e. H/V spectral ratios, were calculated. The results showed that in the whole basin the predominant periods of H/V spectral ratios of all observation points were identical, but with different amplitudes. The in situ geological drillings showed that the peak values of H/V spectral ratio amplitudes at the predominant period (corresponding to 0.72Hz) depended on the depths of soft deposit soil and the distances to the basin center. The fact that H/V spectral ratios on the ground surface in the whole basin had only one predominant period but with different amplitudes indicated that the ambient tremor propagating through the deep and soft soil layers was affected by the three dimensional structure of lacustrine sediments, rather than the local soil depth right under the observation point . Our observations in several other sites showed that the H/V spectral ratios were not sufficient reliable when there were strong vibration sources on the ground surface nearby, meanwhile the H/V spectral ratios in this basin gave a satisfied result. We thought that no obvious vibration sources in this basin guaranteed the reliability of Nakamura method. In addition, amplitudes of H/V spectral ratios at the predominant period should be used in soil velocity inversion when the soil layers vary violently in horizontal plan, which could not be treated as one dimension layered medium any more.

000018518 540__ $$aText je chráněný podle autorského zákona č. 121/2000 Sb.
000018518 653__ $$aambient tremor, Nakamura method, H/V spectral ratio, seismic basin effect, seismic site effect

000018518 7112_ $$a16th World Conference on Earthquake Engineering$$cSantiago (CL)$$d2017-01-09 / 2017-01-13$$gWCEE16
000018518 720__ $$aYushi, Wang
000018518 8560_ $$ffischerc@itam.cas.cz
000018518 8564_ $$s383328$$uhttps://invenio.itam.cas.cz/record/18518/files/1632.pdf$$yOriginal version of the author's contribution as presented on USB, paper 1632.
000018518 962__ $$r16048
000018518 980__ $$aPAPER