Characteristics and Origins of Hot Springs in the Tatun Volcano Group in Northern Taiwan

Abstract

This paper systematically surveyed distribution and field occurrences of 13 hot springs as well as geochemical investigation on the geothermal area of the Tatun Volcano Group (TVG). According to Piper diagrams, pH values, field occurrences and water-rock interactions, these hot springs can be classified into three types: (1) Type I, SO 4 2-acidic water where the reservoir is located in the Wuchishan Formation; (2) Type II, HCO 3 -a near neutral spring where waters originate from the volcanic terrane (andesite); and (3) Type III, Cl --rich acidic water where waters emanate from shallower Wuchishan Formation. In terms of isotopic ratio, δD and δ 18O values, two groups of hot spring can be recognized. One is far away from the meteoric water line of the Tatun area with values ranging between -26.2‰ and -3.5‰, and from -3.2‰ to 1.6‰, respectively. However, another close to the meteoric water line of the Tatun area is between -28.4‰ and -13.6‰, and from -5.5‰ to -4.2‰, respectively. In addition, the δ 34 S value of thermal waters can also be distinguished into two groups, one ranging from 26.1‰ to 28.5‰, and the other between 0.8‰ and 7.8‰. Based on field occurrences and geochemical characteristics, a model has been proposed to illustrate the origin of these hot springs.

Analysis of rbcL sequences reveals the global biodiversity, community structure, and biogeographical pattern of thermoacidophilic red algae (Cyanidiales)

“…Active magma chambers in the TVG area emit sulfurous gases, making the entire area and its surroundings acidic (Liu et al. ). Therefore, the TVG area is an ideal spot for thermoacidophilic cyanidia to grow.…”

“…The Tatun Volcano Group (TVG) area is situated in the northern border of the Taipei basin in northern Taiwan. Active magma chambers in the TVG area emit sulfurous gases, making the entire area and its surroundings acidic (Liu et al 2011). Therefore, the TVG area is an ideal spot for thermoacidophilic cyanidia to grow.…”

Resistivity structure and geochemistry of the Jigokudani Valley hydrothermal system, Mt. Tateyama, Japan

“…However, exceptionally acidic Cl-rich hot springs were reported in the Tatun Volcanic Group (TVG), Taiwan, by Liu et al (2011). They proposed that such waters are derived from a mixture of meteoric water and formation water or seawater with a small amount of magmatic fluids.…”

“…The formation process of hot-spring waters has been discussed on the basis of the major anion concentrations such as chloride, sulfate, and bicarbonate (e.g., Ohba et al, 1997;Liu et al, 2011). The concentration ratios of these three anions represent the immature degree of hydrothermal fluids (e.g., Giggenbach, 1997).…”

Gamma Ray and Radon Anomalies in Northern Taiwan as a Possible Preearthquake Indicator around the Plate Boundary

“…Lin [18] proposed the presence of a deep magma reservoir in the lower crust using S-wave shadow and Pwave delay. In recent years, there have been an increasing number of studies in the TVG area focusing on geochemical investigations and monitoring of the gas compositions, soil flux, and hot spring water [19][20][21][22][23][24][25][26][27] and seismological and geological research, such as seismicity, seismic variations, and ground deformation [16,[28][29][30][31][32][33], which has provided more evidences that the TVG could still be active. As the TVG is located close to the Taipei metropolis and two nuclear power plants, long-term monitoring is necessary for providing possible early warnings of volcano-related hazards and major earthquakes.…”