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Thermal and nonthermal, mineral and non-mineral spring waters in different physical and chemical characters occur along the active Fethiye-Burdur fault zone (FBFZ) in the southwestern Turkey and discharge mainly within the supra-subduction-type ophiolitic units of the Teke nappes. This research aims to determine the physical and hydrogeochemical characteristics, origin, and geochemical evolution of the groundwaters discharging from the same lithology and tectonic zone within the northeastern extend of the active Fethiye-Burdur fault zone. A total of representative nine groundwater samples were collected from the study area. Of which, one of the samples is thermal, and others are nonthermal groundwaters. One of the nonthermal groundwaters is mineral water type, and the other one is hyperalkaline (pH > 10). Based on the analytical results, the waters in the study area are divided into six different groundwater facies: (i) Mg-Ca-HCO3-SO4, (ii) Mg-HCO3-CO3, (iii) Ca-HCO3, (iv) Ca-Mg-HCO3, (v) Mg-HCO3, and (vi) Ca-Na-Cl-CO3 facies. The chemical characteristics of the groundwaters are mainly related to mineralogic and hence chemical composition of sub-surface rocks, residence time of the groundwater, and water-rock intereactions, whether or not the conditions closed to CO2. Neutral to moderate alkaline (pH 10) Ca-Na-Cl-CO3-type waters within deeper ultramafic rock aquifers under the conditions closed to CO2. Mainly altered mafic-ultramafic silicates and carbonate rocks are the major sources of mineralization in the study area. On the other hand, H2S (most probably magmatic origin) reacted with carbonate rocks underlying the ophiolitic melange units produced CO2(g). Dissolution of CO2 within groundwaters is thought to cause arising of acidic conditions, higher degree dissolution of mafic-ultramafic silicates, and mineral water formation.

Potassic, ultrapotassic lava domes, flows, and volcano-sedimentary deposits including leucite-bearing and leucite-free grains crop out to the north of Senirkent (Isparta), at the apex of the Isparta Angle (southwestern Turkey). Ultrapotassic rocks are nepheline-foidolite, italite, leucitite, melilite leucitite, melilite-gehlenite leucitite, diopside leucitite, and leucitophyre with lowest SiO2 content (38.71–44.72 wt%, but the leucitophyre has 51.4 wt%), higher K2O (4.36–10.19 wt%), MgO (3.25–6.98 wt%), and K2O/Na2O ratio (2.65–32.8). Potassic rocks are phonolitic leucitites, sanidine-phyric phonolite, and trachytes with SiO2 (49.35–64.46 wt%), K2O (8.28–11.38 wt%), MgO (0.17–1.39 wt%), and K2O/Na2O ratio (2.25–11.8). Some leucitites, diopside leucitites, and phonolitic leucitites enclose partly carbonatite occurences or associated with carbonate-rich part including carbonatite globules, phlogopite, clinopyroxene, and/or leucite, melanite crystals embedded in glassy volcanic matrix and/or carbonate matrix. Primitive mantle-normalized incompatible element patterns display strong enrichments in LILEs (Cs, Rb, Ba, U, Th, Sr) relative to HFSEs (Nb, Ti) with distinct negative Nb–Ti anomalies, suggesting subduction-related lavas. Chondrite-normalized REE patterns are characterized by light REE enrichment (251–493 times chondrite for La) and flat heavy REE patterns (10–27 times chondrite for Yb). All the leucite-bearing and leucite-free rocks display similar, subparallel chondrite-normalized and primitive mantle-normalized trace element patterns, suggesting cogenetic origin. Mineralogical, petrological, and geochemical data suggest magma–carbonate wall-rock interaction and tapping of different parts of the melts within the magma chamber along the fault lines formed during neotectonic period and extension-related block faulting.