## 5 Discussion
### Provenance  
#### 5.2.1 Mineralogical Approach  
Quartz occurs in most sedimentary, metamorphic, and igneous rocks [82]. As a detrital component, it is highly resistant to physical and chemical weathering, so it is usually preserved in large quantities and is the most abundant terrigenous mineral in sandstones [83; 84]. In the case of the Tunjice Hills, different types of quartz are present. Detrital quartz in the form of monocrystalline or polycrystalline quartz grains and metamorphic and igneous quartz are found in the sandstones [56]. The sandstones of the Tunjice Hills also contain considerable amounts of authigenic quartz, formed by authigenic processes during the cementation of sands [56]. Quartz is a common mineral in various hinterland types and can be found in volcanic rocks (tonalite, granodiorite) and metamorphic rocks (inclusions in eclogites, garnet, omphacite, and kyanite); therefore, its origin could be related to the provenance from the Austroalpine units, from the Eisenkappel magmatic zone [51; 54; 85; 86] or the Smrekovec volcanic complex [54]. Carbonate minerals occur in almost all sedimentary rocks. The most common and most stable polymorph of calcium carbonate mineral is calcite [87]. Calcite determined in the studied samples is most likely of authigenic origin as calcite cement, formed in shallow marine environments [56; 88]. Additionally, detrital calcite and dolomite minerals may be associated with grains from carbonate rocks of the Southern Alps. During the Miocene, the transgressions of the Central Paratethys flooded the wider area several times [44; 60; 78; 88], which led to larger amounts of mainly calcite--also aragonite and dolomite--which is excreted biogenically by marine organisms (skeletons, shells) [47]. The Sarmatian samples contain less calcite and dolomite compared to the Badenian samples from the Tunjice Hills, which could be attributed to variations in seawater salinity. Salinity began to decrease in the Sarmatian [44; 74], which most likely led to a decrease in calcite in the early Sarmatian samples. Generally, the late Sarmatian is characterized by increased carbonate content [89]; however, the sedimentation in the Tunjice Hills most likely ended before that. Differences in the amounts of dolomite and calcite may also indicate differences in the transport system during the Badenian and Sarmatian. The presence of dolomite may be related to terrigenous origin. Its presence in the form of dolomite cement is unlikely [56]. Dolomites may be associated with the influx of material [88] from the Southern Alps, where Triassic dolomites occur. This suggests a local origin and a provenance from the north. Feldspars pose a challenge for accurate source rock identification because they are ubiquitous in metamorphic and igneous rocks [90] and are chemically and mechanically unstable in the sedimentary environment [83]. In the Tunjice Hills, feldspars are represented by plagioclase (Ca and Na feldspars) and alkali feldspars. Their origin could be related to the low-grade metamorphic rocks of Mt. Kranjska Reber and/or to the Smrekovec volcanic complex [54; 91]. The possible hinterland of the feldspars might also represent the Periadriatic magmatic zone or the Austroalpine units of the Eastern Alps [85; 88; 92]. Chlorites are commonly found in metamorphic rocks, particularly greenschists and chlorite shales, as well as altered igneous rocks [83]. Clinochlore (Mg-chloride) has been detected in Badenian and Sarmatian samples from the Tunjice Hills. Mg-rich chlorite is typically found in evaporite deposits. Furthermore, chlorite forms during burial diagenesis and metamorphism [73]. Thick evaporite sediments were deposited in the Transcarpathian Basin, Transylvanian Basin, and Carpathian Foredeep (PBS) during the middle Badenian [78; 93; 94], which can be attributed to a salinity crisis. Evaporite sediments were not detected in the Tunjice Hills nor in the SW Central Paratethys [37], but their remains may have been washed away.