Generalised hydrogeological map of Lower Saxony, 1 : 500 000 - Groundwater quality - Iron
(HUEK500GWB_FE)
The generalised hydrogeological map of Lower Saxony, 1 : 500 000 - Groundwater quality: Iron content, shows the evaluation of a representative sample of iron concentrations taken from the LBEG laboratory database. The data collected in the period 1967-2000 were averaged twice. Where groundwater monitoring wells were subject to multiple analyses, the averages of the available analysis results were formed. In addition, the data from all sampling wells in a 2000 m radius were averaged again.
The classes were formed taking the potable water regulations (Trinkwasserverordnung - TVO) limit value of 0.2 mg/l into consideration. Increased concentrations which are obviously caused by point-source anthropogenic inputs (e.g. abandoned landfills), are not included in these generalised maps. The iron levels are shown in depth stages without reference to the local hydrogeological situation. The data therefore cannot be compared without taking the respective hydrogeological situation into consideration (e.g hydrogeological layering), nor can the data be adopted for detailed investigations.
The iron concentration in the groundwater is heavily influenced by the pH and the redox conditions. Lower Saxony's highest iron levels are reached in acid and/or strongly reducing water. On the other hand, high concentrations of carbonate and sulphide ions facilitate siderite and iron sulphide precipitation and thus restrict the solubility of iron. In addition, where the concentrations of dissolved organic carbon are high, a large proportion of the iron is adsorbed on organocomplexes.
Generally, the iron levels in consolidated rock aquifers in Lower Saxony's mountains are considerably lower than in the Quaternary sediments. The lowest iron concentrations, at 0.01 to 0.1 mg/l maximum, are found in Mesozoic limestones. Higher values are observed in Mesozoic sandstones. In Palaeozoic rocks of the Harz mountains values range between 0.1 and 0.5 mg/l. The oxygenated groundwater in northern Lower Saxony (e.g. Lüneburger Heide) displays iron concentrations in the range 0.1-1 mg/l. In rare cases up to 2 mg/l are reached. In northern Lower Saxony's lowlands, the TVO's 0.2 mg/l limit value is often exceeded.
Iron concentrations of 2-10 mg/l are often observed in the ascending groundwater where longer flow paths are involved. Very high iron levels, between 10 and 40 mg/l, can also be found in groundwater influenced by moors (e.g. Vehnemoor south west of Oldenburg and Teufelsmoor north of Bremen). In contrast to this, ferruginous groundwaters in Hannover's north (Isernhagen, Langenhagen), with concentrations up to 40 mg/l, are probably the result of pyrite oxidation in Lower Cretaceous mudstones.
Informations about data
- Editing state:
Erfassung bzw. Erstellung der Daten ist abgeschlossen (completed).
- Date of last publication:
01.06.2008
- Information about data origin:
An Datengrundlagen sind eingegangen:
- Daten des NIBIS, einzelner Wasserversorger und des Niedersächsischen Landesbetriebs für Wasserwirtschaft, Küsten- und Naturschutz (NLWKN), Stand: März 2000
Contact person
Phone:
+49 511 643-3613
Fax:
+49 511 643-533613
Online access to data
To access the data online you can use the following applications/services:
Distribution information
Common informations (order proccess, product choise, prices):
Kostenfreier Download über den NIBIS-Kartenserver oder Kosten über den Datenvertrieb des LBEG entsprechend der Gebührenordnung
Data formats
- ArcGIS-Shapefile
(
Version:
unknown)
- JPEG
(
Version:
unknown)
- PDF
(
Version:
unknown)
- TIFF
(
Version:
unknown)
Data medium
- CD-ROM (cdRom)
- Ausdruck (hardcopy)
- DVD (dvd)
Distribution contact
Phone:
+49 511 643-3354
Fax:
+49 511 643-533354
Additional information about the data
- Format of data:
digitale Karte in Raster- oder Vektorform (mapDigital)
- Topic:
Geowissenschaften
(geoscientificInformation)
- Key words:
sgd_Hydrogeologie, inspireidentifiziert, opendata, NIBIS-Metadaten, opendata
- Key words GEMET:
Geology
- Thesaurus name:
GEMET - INSPIRE themes, version 1.0
- Thesaurus date of puplication:
2008-06-01
- Geometry type:
Punkt (point)
- Scale:
1:500000
- Coordinate system:
4647; ETRS89 / UTM zone 32N (zE-N)
(Europäisches Terrestrisches Referenzsystem von 1989 / Universale Transversale Mercatorabbildung Zone 32N)
- Altitude reference system:
DE_DHHN92_NH
- Reference layer:
Datenbestand (dataset )
- Language:
ger
- Character set:
utf8
Access- and security restrictions
- Security classification:
unbeschränkt (unclassified)
- Restriction of application:
Es gelten keine Zugriffsbeschränkungen.
Information about content (auto detected)
- Amount datasets/features:
2189
- Spacial notation:
vector
- Eastern longitude:
6.5475
to
11.7416
- Northern latitude:
51.225
to
53.9343
About this data description
- Metadata standard:
Standard
ISO 19115
,
version
ISO 19115:2003/Cor. 1:2006 (E)
- Metadata status:
10.12.2024
- Metadata language:
ger
- Metadata character code:
utf8
Metadata contact