HR: 0800h
AN: PP11A-0211 [Abstracts]
TI: Basement and Stratigraphic Characteristics around Kansai International Airport (KIX), Osaka sedimentary basin, Japan - Integrated Analysis of Geophysical Data -
AU: * Inoue, N
EM: naoto@geor.or.jp
AF: Geo-Research Institute, 4-3-2@Itachibori, Nishi-ku, Osaka, 550-0012, Japan
AU: Kitada, N
AF: Geo-Research Institute, 4-3-2@Itachibori, Nishi-ku, Osaka, 550-0012, Japan
AU: Takemura, K
AF: Institute for Geothermal Sciences, Graduate School of Science, Kyoto University,
Noguchibaru, Beppu, 874-0903, Japan
AB:
Osaka sedimentary basin in the southwest Japan, includes Osaka Bay and Osaka Plain. Several urban areas are
situated around the bay. The basin is surrounded by many active faults. Detailed underground structure plays
important role to seismic hazard for urban areas. The basin consists of granitic basement and overlaying thick
unconsolidated sediment called as the gOsaka Grouph. Several marine clay layers of the Osaka Group are
key layer for stratigraphy and are useful for interpretation of seismic profiles in the basin because marine clay
layer is continuous and indicate wide distribution. The bottom of marine clay layer is confirmed clearly in the
seismic profile due to high acoustic impedance between clay and coarse sediments. Many detail geological and
geophysical information have been accumulated as the results of various survey after the 1995 Kobe Earthquake.
These survey revealed underground structure and stratigraphy of Osaka Group of northwestern part of the basin.
On the contrary, there are few subsurface information in the southeastern part of the basin. Several survey for
estimation of seismic hazard, were carried out in the southeastern part of the basin. In the view point of the
stratigraphy, Kansai International Airport (KIX) plays significant role. New second runway was opened at 2nd Aug.
2007. Before constructing the KIX airport, many geological and geophysical surveys have been performed.
Accumulated data are basic information of stratigraphy and sedimentary environment in the southern part of the
basin. Gravity and tremor surveys were carried out to estimate underground structure beneath the second runway
before opening the runway. Deep borehole to basement is drilling in the second runway. The information derived
by this borehole provides remarkable information. Recent deep borehole information will modify previous results.
Thus, we summarized previous study to compare new results. In this study, we summarized information derived
form geophysical surveys. The basement configuration were inferred form compiled result of gravity, tremor and
seismic surveys. The seismic profiles around KIX were attempted to re-interpretation. In the poster, we will
discuss characteristic of the local sub-basin with the basement configuration and interoperated seismic profiles.
DE: 0920 Gravity methods (1219)
DE: 0935 Seismic methods (3025, 7294)
DE: 1641 Sea level change (1222, 1225, 4556)
DE: 3022 Marine sediments: processes and transport
DE: 8169 Sedimentary basin processes
SC: Paleoceanography and Paleoclimatology [PP]
MN: 2007 Fall Meeting