Hydrogeochemical characteristics and geothermometry of hot springs in the Altai region, Mongolia

Abstract

This study determines the properties of hot spring waters and associated rocks, calculates reservoir temperatures and depths in the Mongolian Altai region, and constructs a conceptual model for geothermal water based on these results. The hot springs consist of HCO3-Na, SO4-Na, and HCO3-SO4-Na mixed type waters. The waters exhibit alkaline pH levels and temperatures in the range of 21.3–35°C. X-ray diffraction analyses of outcrop rocks reveal silicate and carbonate-type minerals such as quartz, albite, orthoclase, dolomite, mica, and actinolite, while correlation analysis indicates that the chemical composition of the hot spring water is directly related to rock mineral composition. Dissolution of albite, orthoclase, and dolomite minerals has played an important role in the chemical composition of the waters. Reservoir water circulation depths were 2615–3410 m according to quartz and chalcedony geothermometry. The results indicate that the spring water in the Mongolian Altai region comprises a low mineral content with alkaline pH levels and the reservoir temperature can reach up to 106°C. We also propose a conceptual model for geothermal water in the Chikhertei hot spring. The geothermal water in the Mongolian Altai region exhibits a potential for use in heating systems.Thematic collection: This article is part of the Hydrochemistry related to exploration and environmental issues collection available at: https://www.lyellcollection.org/cc/hydrochemistry-related-to-exploration-and-environmental-issues

Hydrogeochemical study of hot springs in western region of Mongolia

“…Манай оронд нийт 250 гаруй халуун, хүйтэн рашаан бүртгэгдсэний 42 нь халуун рашаан юм. Тэдгээрээс Баруун бүсэд Монгол-Алтайн мужийн 4 халуун рашаан, Хангайн мужийн 5, нийт 9 халуун рашаан тархсан байна [5,6]. Баруун бүсийн халуун рашааны нөөц, ундаргыг О.Намнандорж, Ө.Нямдорж, Ш.Цэрэн нарын судлаачид Ганц мод 2160 л/цаг, Индэрт 1800 л/цаг, Зарт 4500 л/цаг, Отгонтэнгэр 300000 л/цаг, Цэцүүх 300 л/цаг, Чихэртэй 3600 л/цаг, Аксу 60 л/цаг нөөцтэйг тогтоосон байна [7].…”

“…Хүснэгт 2-т үзүүлснээр Индэртийн рашааны эрдэсжилт 712 мг/л агуулгатай байхад бусад рашааны хувьд, эрдэсжилт нь 500 мг/л-ээс ихгүй буюу бага эрдэсжилттэй байна[4]. Индэртийн рашааны эрдэсжилт их байгаа нь чулуулгийн шинж чанар болон газар нутгийн онцлог, цаг уурын хүчин зүйлтэй холбоотой гэж үзэж байна[3,5]. Баруун бүсийн халуун рашааны 42 цэгийн дээжний үр дүнг ашиглан эрдэсжилт нь температур болон рН-ийн муж дахь тархалтыг зураг 2-д харуулав.…”

Hydrogeochemical Characteristics of Geothermal Water in Ancient Deeply Buried Hills in the Northern Jizhong Depression, Bohai Bay Basin, China

“…Carbonate thermal reservoirs distributed in this area generally have the advantages of a large development scale, large thermal storage capacity, high quality of water, and easy recharge [10][11][12]. In recent years, geochemical methods such as hydrochemistry and isotope have had unique advantages in revealing the recharge source of geothermal water [13][14][15][16][17][18], deducing the water-rock reaction process, and discussing the formation mechanism of geothermal water. Many scholars have used geochemical methods to study the recharge sources, thermal storage temperature, and groundwater mixing in the Jizhong Depression (such as the Xiong'an New Area) [19][20][21][22].…”