Geological Survey Ireland Programmes & Projects Tellus Tellus – Activities Ground Survey Ground Survey technical specifications

Ground Survey technical specifications

As part of the geochemistry programme, a wide range of elements and compounds are measured in three environmental media: topsoil, stream water and stream sediment. Other samples collected but not routinely analysed include subsoil, vegetation and panned concentrate samples – these are available from the GSI archive on request.

​  Shallow Soil​
​1. Sampling– Composite sample from points and centre of 20 m x 20 m square
– Collection by hand auger to 20 cm and 50 cm depths 		​2. Preparation– Drying
– Disaggregation
– Milling to fine powder pulp
​3. Analysis– Multi-element ICP-MS
– Multi-element XRFS
– pH and Loss-on-ignition (organic carbon)		​4. Data Processing– Quality control
– Statistical analysis
– Mapping
– Interpretation
Stream Sediment​ ​
​1. Sampling– In-situ wet sieving technique from small streams
– Collection of <150 µm fraction		​2. Preparation– Drying
– Disaggregation
​4. Analysis– Multi-element XRFS
– Precious group elements fire assay 		​3. Data Processing– Quality control
– Statistical analysis
– Mapping
– Interpretation
​Stream Water ​
​1. Sampling Collection of filtered water, <0.45µm ​2. Preparation Acidification
​3. Analysis– Multi-element ICP-MS
– Major ions IC
– Organic carbon 		​4. Data Processing– Quality control
– Statistical analysis
– Mapping
– Interpretation