全世界間歇泉大約1,000處且位於火成岩區，唯獨臺灣的間歇泉位於低度變質碎屑岩。本研究為首篇以連續監測方式採集土場溪流域的河水、自湧泉及間歇泉，利用感應耦合電漿原子發射光譜儀、離子層析儀、自動滴定儀分析樣品的地球化學徵，以曲線擬合及集群分析探討各種水體的關係。
本研究結果顯示，土場溪流域有2個地熱儲集層，一個儲集層位於能大量溶解板岩中鈣離子的深度，此地熱儲集層熱水為自湧泉供應來源，其水體鈣含量則高於河水。另一個地熱儲集層則位於能大量溶解板岩中鈉離子和鉀離子的深度，這個地熱儲集層熱水為噴泉及間歇泉的供應來源，其水體以鈉和鉀離子為主，鈣與鎂離子的含量相當低。
There have 1,000 geysers distribution in igneous rock of the world, only the geyser of Taiwan locates in low-grade meta-clastic rock. This firstly research collected samples from river, thermal water, artesian and geysers of Tuchang River by long term. This study analyzed the geochemistry of samples by Inductively Coupled Plasma - Atomic Emission Spectrometry (ICP-AES), Ion - exchange Chromatography (IC) and Automatic Titration. Finally, this study applied the methodologies of curve fitting and cluster to identify origins of samples.
This study shown that there have two geothermal reservoirs in Tuchang River. The origin of thermal water sites in the geothermal reservoir of shallow depth and enriches calcium. The origin of artesian of well and geyser locates in the geothermal reservoir of deeper depth and has enriched sodium and potassium.
