"# J. Hot Spring Sci. /2 ,1-ῌ,2+ ,**3ῌ῎ + +  + ,*++

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Hot Springs and Geological Features of Ibaraki PrefectureExploring Heat Sources and Groundwater Veins
Yuu HORIKAWA+, Katsumi KASAI+ and Tadashi TOBITA+

Abstract
In Ibaraki Prefecture, geothermal resources of high temperatures are poor because oflack of presently active volcanic belt. Natural hot springs, thus, that had enough temperatures for bathing are few. However, due to progress of drilling technique and pumpingsystem, artiﬁcial hot springs have been recently developed in places. Our company,
Ibaraki Onsen Kaihatsu (Ibaraki Hot Spring Developer Co. Ltd.) has challenged to develop
hot springs since +30/, mainly in Ibaraki Prefecture, and we had successfully developed
more than forty hot springs. Through our achievement, we have ascertained that heat
resources and groundwater veins, which were not thought to locally exist but widelydistribute in Ibaraki Prefecture. This paper discuss hot springs and geological features inIbaraki Prefecture on the basis of. our experiences and achievements for obtaining hotwater discharge in order to apply the knowledge to development of hot springs in future.
Key words : Ibaraki Prefecture, hot springs, heat sources, groundwater veins, development of hot spring, geothermal gradient῏῍$%&'(&)*+,-./0,12345!678%9:1 ;523 <=%>?,0@A%BCDE80F,GH2 :G: IJKLMNOPQ5RS%TUVW&XYZY,[\%]1^_`+%aWbETc%,H^b2 
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Co. Ltd., +222, Ootsuka-cho, Mito, Ibaraki Prefecture -++ῌ.+.-, Japan.

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