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Development of the shallow-groundwater resources is
considered to solve the problems of water resources for
industrial and residential usage. Obviously, topography and
geology have a lot of influence of forming of the
shallow-groundwater system, which can be studied by
coordinating the "boring log" and the "geophysical
exploration" methods. Riverbed in Hsilo section of Cho-Shu
river is composed of sands and sandy-gravels. Shallow-
groundwater is usually exists beneath riverbed. Sandy-gravel
layer with better permeability can be used as water
collection system; however, electrical prospecting method
cannot tell the small difference of apparent resistivity
between sands and sandy-gravel layers. Therefore, the
research tries to coordinate the seismic refraction method
and the shallow seismic reflection method to judge the sandy-
gravel layer location. In order to get better ordinary
records, we had collected some data before the real research
began. First, we collected related hydrogeologic information.
Second, we investigated the site field in order to decide
proper measuring area. Third, we estimated field structures
by researching shallow field materials and by studying boring
logs'' information nearby. Forth, we did noise test and
decided the operation parameter and work time. After
collecting all information, we organized data and made
detailed analy sis to get helpful results. Coordinating the
results of seismic reflection and shallow seismic
reflection can not only map the interface between sand layer
and sandy-gravel layer beneath the groundwater, but also
draw a picture of existing water layer structure in the
measured area. After discussing all related data, we think the
shallow-groundwater the measured area streams toward river
course from east to west beneath the loosen covering clay.
Finally, we think that the way that coordinates the seismic
reflection method and shallow seismic reflection method is
a good technique to investigate water resources deplacement
systems.
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