• 한국지구물리탐사학회:학술대회논문집
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• 2008.10a
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• pp.149-154
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• 2008

We analyzed the Coulomb stress transfer near a small-scale reverse fault. For the modeling we used the geometry of a Quaternary fault in Gyeongju area, Eupcheon fault. For an assumed reverse faulting slip of 10cm, the resulting values of the Coulomb stress change are relatively higher (>2 bar) near the edges (both downward and lateral) of the fault, and diminish slightly upward and downward. The equivalents are negative in the zone immediately below and above the fault, exhibiting a "T" shape of low stress zone in the vertical profile of the fault. This study demonstrates the possible ranges and directions the aftershock energy would propagates after a reverse faulting.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 1998.10a
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• pp.235-240
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• 1998

Quaternary fault movement of the Ulsan fault system was interpreted by aenal photograph, field survey and trench excavation. The geomorphological evidences associated with active fault are clearly shown at Cheonbuk-myeon area, northern part of Ulsan fault system. In the trench wall one reverse fault(N 50$^{\circ}$E, 70$^{\circ}$E) is identified between basement rock (Miocene mudstone) and gravel deposits Another thrust fault (NS) extends up to the red and light brown soil layers. Middle terrace surface shows cumulative vertical displacements of about 3 to 7 m. The horizontai displacement of the red soil by faulting event is about 1.8 to 2.4m. The age of the fault activity is younger than that of the soil layer, which is roughly estimated to be late Quaternary (about 100Ka)