# Trace Elements and Mineralogy of Upper Permian (Zechstein)
## 5 Geology and Sampling of Potash-Bearing Deposits
### Potassium-Bearing Deposits of PZ2 Cyclothem  
The potash-bearing deposits of PZ2 cyclothem represent two lithost stratigraphic units: the Transitional beds Na+K2 and the Older Potash (K2). They are underlain by the chlorides of Older Halite (Na2) units and overlain by rock salts of the Screening Halite (Na2r) or by the Screening Anhydrite (A2r) units. These potash rocks were sampled in the four salt domes: Damaslawek, Gora, Klodawa, and Mogilno. \begin{table}
\begin{tabular}{c c c c c} \hline \hline \multirow{2}{*}{**Location**} & \multirow{2}{*}{
\begin{tabular}{c} **Zechstein** \\ **Lithost stratigraphic Units** \\ \end{tabular} } & \multicolumn{4}{c}{**Type of Analyse**} \\ \cline{3-5}  & & **Chemical** & **XRD** & **Petrographic** \\  & & **(Elements Content)** & **(Mineral Composition)** & **(Mineral Composition)** \\ \hline Puck Bay surroundings & A1d & 9 & 2 & 8 \\ \hline Góra salt dome & Na2+K2, K2 & 1 & 1 & 6 \\ \cline{2-5}  & Na3+K3, K3 & 4 & 4 & 4 \\ \hline Damaslawek salt dome & Na2+K2, K2 & 11 & 4 & 1 \\ \cline{2-5}  & Na3+K3, K3 & 4 & 3 & 1 \\ \hline Mogilno salt dome & Na2+K2, K2 & 7 & 3 & 5 \\ \cline{2-5}  & Na3+K3, K3 & 6 & 4 & 4 \\ \hline Klodawa salt dome & Na2+K2, K2 & 73 & 20 & 2 \\ \cline{2-5}  & Na3+K3, K3 & 193 & 14 & 6 \\ \hline Total number of analyses & 308 & 55 & 37 \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Types, number, and location of analyses of sampled Zechstein potash-bearing deposits in Poland. The Older Potash seam in the Fore-Sudetic area, several to 24 m thick, is composed of repetitive yellow to red layers of rock salt, salt with sylvite and anhydrite-polyhalite-halite beds [85; 86; 87; 88; 89; 90; 91]. The main minerals are halite, sylvite, polyhalite, anhydrite, with minor addition of clay matter, and iron oxides, less frequent are quartz and borcate aggregates. The potash-bearing complex in the Klodawa salt dome is 11-17 m thick including the Transitional beds Na2+K2 of ca. 5 m [92]. These beds are composed of white-grey coarse crystalline rock salt (Figure 3) with a clay admixture and anhydrite laminae, as well as more or less regular concentrations and interfingers of K-Mg salts, dominated by kieserite, polyhalite, carnalite, and sylvite [93]. The overlain Older Potash (K2) unit is composed of anhydrite-sylvite-polyhalite rock (Figure 4) admixed with carnalite and kainite in the lower part [93]. This complex was sampled (70) in three galleries located at mine levels 600 m and 750 m of the underground salt mine KLODAWA S.A. [30; 49]: Z2/1 profile (29 samples; Figure 3), Z2/2 profile (19 samples) and Z2/3 profile (22 samples). They are supplemented by geochemical data of three samples taken from other three galleries at mine level 750 m [52]. The potash-bearing complex in the Damaslawek salt dome is composed of a repetitive (Figure 5) series of Transitional beds Na2+K2 and Older Potash (K2), ca 1.5 m thick [31]. They are built by white-grey-red polymorphic halite kieserite salts with laminae and aggregates of kainite, anhydrite, and clay matter. Ten samples were taken from the cores of Damaslawek A (seven samples) and Damaslawek B (three samples) boreholes (Figure 6). Figure 2: Sampled profile of Mieroszyno M-9 borehole with polyhalite interbeds within the Lower Anhydrite (A1d) unit. M-9/1, 769.2—sample number and depth in metres, in frame—thin section (sample M-9/2) on Figure 11.  
Figure 4: Sample of kieseritic salt from the Older Potash (K2) unit. The Z-2/1 section in the gallery of salt mine KLODAWA S.A., Klodawa salt dome. Figure 3: Sampled profile Z-2/1 of Na2+K2 and K2 lithoststratigraphic units in the gallery of salt mine KLODAWA S.A., mine level 600 m, Klodawa salt dome. In the Gora salt dome, the Older Potash (K2) unit is developed as repetitive beds impressed within the huge profile of Older Halite (Na2). It is comprised of thin laminae and layers, several to a dozen or so cm thick, of medium to coarse crystalline K-Mg salts, highly tectonised and reduced. Only a single sample was taken from the core of the G-41 borehole (Figure 7).