OR Moravský Svätý Ján – dolné

Geological structure beneath the water

Which rock lies beneath the water line (Geological Map of Slovakia 1:50,000), how old it is, how thick the Quaternary cover is and in which tectonic unit the water flows. The bedrock decides the hardness of the water, the bottom, the turbidity after rain and the abundance of springs.

The points follow the water line (for a stream and a basin, fishing district after fishing district). The strip is a cross-section by distance, not a map; the width of a section corresponds to the number of points.

• River alluvium100%SR 72 %

marker on the bar: share among all sample points on streams in Slovakia

River alluvium: Gravelly and sandy bottom and floodplains; the water is replenished from groundwater in the alluvium.

Geological age of the rocks

• Quaternary100%

Most common rock units

Quaternary cover

• fluvial sediments of floodplains100%SR 68 %

marker on the bar: share among all sample points on streams in Slovakia

• Typical thickness of the Quaternary cover7.5m

• 5 – 10100%SR 20 %

marker on the bar: share among all sample points on streams in Slovakia

Tectonic division

• NEOALPÍNSKE TEKTONICKÉ ŠTRUKTÚRY ZÁPADNÝCH KARPÁT100%SR 84 %

marker on the bar: share among all sample points on streams in Slovakia

Neotectonic units

• positive unit (lowland hills)100%SR 14 %

marker on the bar: share among all sample points on streams in Slovakia

Direction of neotectonic movements

• very small uplift100%SR 6.4 %

marker on the bar: share among all sample points on streams in Slovakia

Regional geological division

• intramontane basins100%SR 44 %

marker on the bar: share among all sample points on streams in Slovakia

Regional geological division (subunits)

• Vienna Basin100%SR 4.0 %

marker on the bar: share among all sample points on streams in Slovakia

Engineering-geological districts

• region of lowland-stream deposits100%SR 20 %

marker on the bar: share among all sample points on streams in Slovakia

Engineering-geological formations

• formation of Quaternary sediments100%SR 71 %

marker on the bar: share among all sample points on streams in Slovakia

Susceptibility of the area to slope deformations

• Region of stable areas100%SR 95 %

marker on the bar: share among all sample points on streams in Slovakia

The map covers 1 of 2 points on the water line.

Hydrogeology: aquifers and groundwater

Streams and rivers are fed by groundwater. Hydrogeological maps show in which rocks the water is stored, how permeable they are and what the water in them is like. The data come from ŠGÚDŠ maps, not from measurements at a particular water.

Type of permeability (basic hydrogeological map 1:50,000)

• intergranular100%SR 86 %

marker on the bar: share among all sample points on streams in Slovakia

Hydrogeological function

• aquifer100%SR 95 %

marker on the bar: share among all sample points on streams in Slovakia

Main hydrogeological region

• Quaternary of the Morava from Brodské to Vysoká pri Morave100%SR 0.0 %

marker on the bar: share among all sample points on streams in Slovakia

Surface water chemistry according to the atlas

Modelled composition of the water in the area the fishing district line runs through. The rasters of the Geochemical Atlas of Slovakia (surface waters) are an interpolation of measurements in sampled streams, so they show the typical background of the area, not a measurement in a particular stream.

Ionic composition of the water

Water type by dominant ions: Ca–HCO₃

Shares are in equivalents, the usual way of comparing the composition of waters.

Major ions

• FluoridesF0.279 mg/lpercentile 92
• PotassiumK8.60 mg/lpercentile 90
• ChloridesCl42.4 mg/lpercentile 87
• SodiumNa27.2 mg/lpercentile 87
• SulphatesSO467.3 mg/lpercentile 74
• MagnesiumMg16.4 mg/lpercentile 54
• CalciumCa61.9 mg/lpercentile 49
• BicarbonatesHCO3190 mg/lpercentile 42

dot: average along the water line, line: from the lowest to the highest value, scale: position among sample points on streams in Slovakia (0 to 100th percentile)

Nutrients and organic pollution

• Chemical oxygen demandChSK13.0 mg/lpercentile 95
• AmmoniumNH41.88 mg/lpercentile 95
• PhosphatesPO40.420 mg/lpercentile 76
• NitratesNO310.5 mg/lpercentile 74

Metals

• ManganeseMn350 μg/lpercentile 94
• ZincZn19.8 μg/lpercentile 86
• IronFe0.279 mg/lpercentile 83
• AluminiumAl62.7 μg/lpercentile 49

Elements in river sediments

The Geochemical Atlas of Slovakia (river sediments) describes what the river carries in the fine material on its bed. Sediment collects metals from rocks, ore occurrences and past mining and industry. It is not a legal limit or a health risk assessment: it shows how an element on this stream ranks among streams in Slovakia.

Potentially toxic and trace elements

• SeleniumSe0.206 mg/kgpercentile 40
• MolybdenumMo0.277 mg/kgpercentile 29
• TinSn2.15 mg/kgpercentile 28
• ChromiumCr56.5 mg/kgpercentile 25
• LeadPb11.8 mg/kgpercentile 25
• NickelNi17.3 mg/kgpercentile 19
• CobaltCo6.13 mg/kgpercentile 16
• CadmiumCd0.0675 mg/kgpercentile 12
• MercuryHg0.0445 mg/kgpercentile 10
• BismuthBi0.109 mg/kgpercentile 9
• CopperCu13.7 mg/kgpercentile 8
• VanadiumV47.3 mg/kgpercentile 7
• ZincZn47.2 mg/kgpercentile 4
• ArsenicAs2.17 mg/kgpercentile 2
• AntimonySb0.133 mg/kgpercentile 1

dot: average along the water line, line: from the lowest to the highest value, scale: position among sample points on streams in Slovakia (0 to 100th percentile)

Natural radioactivity and radon

Airborne gamma-ray spectrometry by ŠGÚDŠ measures radiation from potassium, uranium and thorium in rocks and soil. Granites and some acidic volcanic rocks have the highest values, limestones and floodplains the lowest. Caesium-137 is a remnant of fallout from the Chernobyl accident and nuclear weapons tests.

• Equivalent thorium (eTh)eTh8.83 ppm82th percentile
• Potassium (K)K1.27 %percentile 35
• Equivalent uranium (eU)eU2.19 ppm15th percentile

dot: average along the water line, line: from the lowest to the highest value, scale: position among sample points on streams in Slovakia (0 to 100th percentile)

• Areal activity of 137CsCS1371,740 Bq/m²percentile 61

Geophysical fields: magnetics and gravity

Maps of the magnetic field and gravity (ŠGÚDŠ) reveal what lies beneath the sediments and the surface: volcanic bodies, faults and crustal thickness. For an angler they are interesting indirectly: they show where the bedrock changes, and with it the water.

Geothermal potential

The Atlas of Geothermal Energy of Slovakia records rock temperature and heat flow from the Earth's interior. It is the potential of the area, not the actual warmth of the water in the stream. Specific geothermal boreholes and springs near this water are in the geothermal energy section below.

Relief, climate and soils

A basin is not just water: slope and elevation determine the speed of runoff, climate the temperature and amount of water, and soils what is washed into the stream. The data come from the geomorphological division, climatic-geographical types and soil maps of ŠGÚDŠ.

• Elevation of geomorphological units (from–to)132–158m a.s.l.
• Average elevation of the units145m a.s.l.
• Average slope0.5°
• Average January temperature-2.5°C
• Average July temperature20.0°C
• Annual precipitation590mm

Geomorphological units

• Borská Lowland100%SR 2.2 %

marker on the bar: share among all sample points on streams in Slovakia

Geomorphological regions

• Záhorie Lowland100%SR 2.5 %

marker on the bar: share among all sample points on streams in Slovakia

Climatic-geographical types

• lowland climate100%SR 38 %

marker on the bar: share among all sample points on streams in Slovakia

Susceptibility of soils to acidification

• soils very susceptible to acidification100%SR 2.4 %

marker on the bar: share among all sample points on streams in Slovakia

Soil contamination (map 1:500,000)

• uncontaminated soil, the geogenically determined content of some risk elements reaches limit values A100%SR 45 %

marker on the bar: share among all sample points on streams in Slovakia

Lithogeochemical types

• Neogene100%SR 48 %

marker on the bar: share among all sample points on streams in Slovakia

Map of the corridor

Where the nearest mine workings, deposits, burdens, geothermal boreholes and gold finds are. Groups can be switched off.

Trace elements in surface waters

Arsenic, antimony, cadmium, lead, copper, zinc and other elements in samples from rivers and streams (Geochemical Atlas of Slovakia, surface waters, 2015). The bar shows where the highest value lies among all samples in Slovakia; the light marker is the median of the samples at this water.

• CopperCuslightly elevated
  highest 4.30 μg/lmedian 1.40 μg/l3 samples33 % below the limit of quantification
  1. up to 50 %
  2. 50–75
  3. 75–90
  4. 90–99
  5. above 99

  Highest value: mŕtve rameno rieky Morava, lok. Rozpad2003, 430 m from the water. Comparison: percentile 89 of all samples in Slovakia.

• ChromiumCrslightly elevated
  highest 4.00 μg/lmedian 1.00 μg/l3 samples67 % below the limit of quantification
  1. up to 50 %
  2. 50–75
  3. 75–90
  4. 90–99
  5. above 99

  Highest value: mŕtve rameno rieky Morava, lok. Rozpad2003, 430 m from the water. Comparison: percentile 87 of all samples in Slovakia.

• ArsenicAsslightly elevated
  highest 3.00 μg/lmedian 1.00 μg/l3 samples33 % below the limit of quantification
  1. up to 50 %
  2. 50–75
  3. 75–90
  4. 90–99
  5. above 99

  Highest value: mŕtve rameno rieky Morava, lok. Rozpad2003, 430 m from the water. Comparison: percentile 83 of all samples in Slovakia.

• AntimonySbslightly elevated
  highest 1.00 μg/lmedian 0.500 μg/l3 samples67 % below the limit of quantification
  1. up to 50 %
  2. 50–75
  3. 75–90
  4. 90–99
  5. above 99

  Highest value: mŕtve rameno rieky Morava, lok. Rozpad2003, 430 m from the water. Comparison: percentile 82 of all samples in Slovakia.

• BariumBaslightly elevated
  highest 77.0 μg/lmedian 71.0 μg/l3 samples
  1. up to 50 %
  2. 50–75
  3. 75–90
  4. 90–99
  5. above 99

  Highest value: mŕtve rameno rieky Morava2003, 310 m from the water. Comparison: percentile 81 of all samples in Slovakia.

• LithiumLislightly elevated
  highest 11.0 μg/lmedian 5.00 μg/l3 samples67 % below the limit of quantification
  1. up to 50 %
  2. 50–75
  3. 75–90
  4. 90–99
  5. above 99

  Highest value: Morava2003, 920 m from the water. Comparison: percentile 76 of all samples in Slovakia.

• SeleniumSebelow half of Slovakia
  highest 0.500 μg/lmedian 0.500 μg/l3 samples100 % below the limit of quantification
  1. up to 50 %
  2. 50–75
  3. 75–90
  4. 90–99
  5. above 99

  Highest value: Morava2003, 920 m from the water. Comparison: percentile 46 of all samples in Slovakia.

• LeadPbbelow half of Slovakia
  highest 2.50 μg/lmedian 2.50 μg/l3 samples100 % below the limit of quantification
  1. up to 50 %
  2. 50–75
  3. 75–90
  4. 90–99
  5. above 99

  Highest value: Morava2003, 920 m from the water. Comparison: percentile 43 of all samples in Slovakia.

• CadmiumCdbelow half of Slovakia
  highest 0.150 μg/lmedian 0.150 μg/l3 samples100 % below the limit of quantification
  1. up to 50 %
  2. 50–75
  3. 75–90
  4. 90–99
  5. above 99

  Highest value: Morava, 920 m from the water. Comparison: percentile 26 of all samples in Slovakia.

Major ions, mineralisation and pH

Basic water chemistry: which rocks the minerals in it come from.

• Silicon dioxideSiO2below half of Slovakia
  highest 9.89 mg/lmedian 2.92 mg/l3 samples
  1. up to 50 %
  2. 50–75
  3. 75–90
  4. 90–99
  5. above 99

  Highest value: Morava2003, 920 m from the water. Comparison: percentile 46 of all samples in Slovakia.

Groundwater: chemistry, water types and radioactivity

Hydrogeochemical objects (analyses of springs and boreholes), the geochemical atlas of groundwater (1996) and radiohydrochemical sampling. Groundwater feeds streams, so its composition also affects the water in the stream.

Metals in groundwater

• AluminiumAlhigh (top 5 %)
  highest 0.140 mg/lmedian 0.0800 mg/l2 samples
  1. up to 50 %
  2. 50–75
  3. 75–90
  4. 90–99
  5. above 99

  Highest value: studňa1994, 2.8 km from the water. Comparison: percentile 97 of all samples in Slovakia.

• ArsenicAshigh (top 5 %)
  highest 5.40 μg/lmedian 2.95 μg/l2 samples50 % below the limit of quantification
  1. up to 50 %
  2. 50–75
  3. 75–90
  4. 90–99
  5. above 99

  Highest value: studňa1994, 2.8 km from the water. Comparison: percentile 95 of all samples in Slovakia.

• SeleniumSehigh (top 5 %)
  highest 2.70 μg/lmedian 1.60 μg/l2 samples50 % below the limit of quantification
  1. up to 50 %
  2. 50–75
  3. 75–90
  4. 90–99
  5. above 99

  Highest value: studňa1994, 2.8 km from the water. Comparison: percentile 95 of all samples in Slovakia.

• AntimonySbhigh (top 5 %)
  highest 0.700 μg/lmedian 0.400 μg/l2 samples50 % below the limit of quantification
  1. up to 50 %
  2. 50–75
  3. 75–90
  4. 90–99
  5. above 99

  Highest value: studňa1994, 2.8 km from the water. Comparison: percentile 95 of all samples in Slovakia.

• ChromiumCrslightly elevated
  highest 1.90 μg/lmedian 1.08 μg/l2 samples50 % below the limit of quantification
  1. up to 50 %
  2. 50–75
  3. 75–90
  4. 90–99
  5. above 99

  Highest value: studňa1994, 2.8 km from the water. Comparison: percentile 89 of all samples in Slovakia.

• CopperCuslightly elevated
  highest 3.60 μg/lmedian 2.50 μg/l2 samples
  1. up to 50 %
  2. 50–75
  3. 75–90
  4. 90–99
  5. above 99

  Highest value: studňa1994, 2.8 km from the water. Comparison: percentile 88 of all samples in Slovakia.

• ZincZnslightly elevated
  highest 247 μg/lmedian 142 μg/l2 samples
  1. up to 50 %
  2. 50–75
  3. 75–90
  4. 90–99
  5. above 99

  Highest value: studňa1994, 2.8 km from the water. Comparison: percentile 80 of all samples in Slovakia.

• LeadPbslightly elevated
  highest 1.00 μg/lmedian 0.750 μg/l2 samples50 % below the limit of quantification
  1. up to 50 %
  2. 50–75
  3. 75–90
  4. 90–99
  5. above 99

  Highest value: studňa1994, 2.8 km from the water. Comparison: percentile 75 of all samples in Slovakia.

• CadmiumCdbelow half of Slovakia
  highest 0.250 μg/lmedian 0.250 μg/l2 samples100 % below the limit of quantification
  1. up to 50 %
  2. 50–75
  3. 75–90
  4. 90–99
  5. above 99

  Highest value: studňa1994, 2.8 km from the water. Comparison: percentile 47 of all samples in Slovakia.

• MercuryHgbelow half of Slovakia
  highest 0.100 μg/lmedian 0.100 μg/l2 samples100 % below the limit of quantification
  1. up to 50 %
  2. 50–75
  3. 75–90
  4. 90–99
  5. above 99

  Highest value: studňa1994, 2.8 km from the water. Comparison: percentile 46 of all samples in Slovakia.

• LithiumLibelow half of Slovakia
  highest 6.00 μg/lmedian 5.00 μg/l2 samples
  1. up to 50 %
  2. 50–75
  3. 75–90
  4. 90–99
  5. above 99

  Highest value: vrt1994, 2.8 km from the water. Comparison: percentile 45 of all samples in Slovakia.

Radon in waters

Mine workings, deposits and ore occurrences

Old mine workings outside mining areas (Geofond register), deposits and mining areas, and the metallogenetic map. Gold, silver and other metals near streams can get into sediments and water.

Deposits and mining areas

Boreholes and Geofond archive reports

Register of hydrogeological boreholes, other boreholes and geothermal boreholes. Each borehole has a report in the Geofond archive (geological profiles, pumping tests, chemical analyses of the water); the report number is in the table.

58 boreholes in the 3 km zone, of which 5 hydrogeological and 53 other; with an archive report number 52.

Borehole depths

• up to 10 m14×
• 10–30 m24×
• 30–100 m4×
• 100–300 m0×
• over 300 m5×

Nearest boreholes