IDENTIFICATION OF STRUCTURES WITHIN THE DEEP GEOTHERMAL RESERVOIR OF THE KAKKONDA FIELD, JAPAN, BY A REFLECTION METHOD USING ACOUSTIC-EMISSION AS A WAVE SOURCE
N. Soma et H. Niitsuma, IDENTIFICATION OF STRUCTURES WITHIN THE DEEP GEOTHERMAL RESERVOIR OF THE KAKKONDA FIELD, JAPAN, BY A REFLECTION METHOD USING ACOUSTIC-EMISSION AS A WAVE SOURCE, Geothermics, 26(1), 1997, pp. 43-64
Structures within the deep geothermal reservoir in the Kakkonda field
have been identified by a newly-developed reflection method using acou
stic emission (AE) as a wave source. Reflected waves in three-componen
t AE signals were detected independently of the wave amplitude by exam
ining the linearity of a three-dimensional hodogram. There are many po
ssible reflectors in this field, such as geological boundaries and fra
ctured regions. In this paper are described some deep reflectors benea
th the conventionally developed shallow geothermal reservoirs that wer
e revealed by three-dimensional inversion of natural AE waveforms. The
se identified reflectors agree fairly well with geological constraints
based on core samples from the field. (C) 1997 CNR.