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1.Metadata Reference (GSI_BHLS)

Metadata Date (dd/mm/yyyy) : 25/08/2005

Last Date (dd/mm/yyyy): 28/03/06

2.Indentification Information

Title : GSI_Bedrock Boreholes

Description :

A national database of boreholes including locational and stratigraphic information. Boreholes must have a locality number to be included in this database; I.e. a grid coordinate must exist for every entry. Where core exists for a given borehole it is linked to the borehole by way of the unique locality number. Boreholes known to open file and boreholes unrecorded in open file are included. The number of records entered so far: 7.549. Number of records remaining to be added from open file.

Keywords: Boreholes, Borehole location, stratigraphic.

Version : 1.0

Language : English

Data type: tabular (.dbf)

3.Lineage Information

Originator org - Bedrock in Section in the GSI.

Other contributors -

Technical contact details - Silvia Caloca.

Principle data capture Technique - Information taken form GSI bedrock drilling

4.Lineage Records.

Filename : GSI Bedrock Boreholes database

Date (dd/mm/yyyy): 05/01/1988

Originator.- Geological Survey of Ireland.

Nature of change/update to data

Ongoing addition of new records as data becomes available. Verification of location of boreholes

Methodology.-

Borehole information obtained from drilling entered in an Oracle database.

Sources Used as input Data for the change /update.-

Main data sources are maps of varying scales, literature and company records, local authorities, well drillers, consultants’ records, GSI field investigations….

Scripts/tools used.-

N/A

Contact details for further information on scripts/Tools.-

Andy Sleeman, The Bedrock Section of the Geological Survey of Ireland,

Beggar's Bush, Haddington Road, Dublin 4.

5.File Structure and maintenance information

Authorised by : Koen Verbruggen (IMP, Geological Survey of Ireland)

Maintenance/ Update frequency -. Weekly

6.Data dictionary: File Name/Field Description/ Field Type .

Fields taken from T:\Bedrock Data\Boreholes.xls

Bhole_Num: Borehole number.

X: Five-figure reference for the east-to-west grid coordinates. Number(6,0)

Y: Five-figure reference for the north-to-south grid coordinates Number (6,0)

County: Name of the County where the borehole is located/ VARCHAR2 (250)

Comp_bhole:

Expr1005

PL: Prospecting license

Comp:

Year: Year on which drilling started.

Month: Month on which drilling started.

Day: day on which drilling started.

Geologist

Angle: the apparent angle of dip of the core strata in the borehole?

Azimuth: The direction in which the borehole deviates from the vertical
is the borehole azimuth.

Length: Length of the borehole.

Od_metres: Correct elevation in metres Malin Number (7,3).

Rockhead: Difference between the ground leveland DTB.

Lith_base: Lithology at the base of the borehole.

Lith_top: Lithology at the top of the borehole.

Strat_base: Name of the stratigraphic unit at the base of the borehole.

Comments:

Loc_Number : Location identification number/Integer (7).

Fields taken from the geodatabase

BORID: Borehole identification number/Integer (7).

LOCID: Location identification number/Integer (7).

REPORTID: Report identification number/ NUMBER (10, 0).

OD_MALIN: Correct elevation in metres Malin Number (7,3).

DTB: Depth to bedrock

DTB_CONFID: Grade of confidence for meeting bedrock Varchar2(2).

HOLEDIP.- the apparent angle of dip of the core strata in the borehole.

HOLEAZ.- The direction in which the borehole deviates from the vertical
is the borehole azimuth.

DEPTH.- Total depth of the borehole in metres. Number (7,3).

UNITS.- original investigation units.

OD_ACCURACY: Relative accuracy of the estimated elevation

OD_SOURCE: Map or other source for the elevation estimate/ Varchar2(10)

GROUNDELEVATION: Ground elevation in metres Number (7,3).

GROUNDELEVATIONOD:Ordnance datum, i.e height above mean sea level.

COLLEROFFSET: difference between drill collar (top of casing) and ground surface/Number (7,3).

COLLERCOMMENT: comments on coller data.

PROSLIC:

COMPANY: It is a report reference number provided by the site investigation company or the consulting engineer /. VARCHAR2 (10).

START DATE.- date the drilling started /Date.

FINISH DATE.- date the drilling finished /Date.

LOGGEDBY.- This refers to holes drilled by GSI and logged by a GSI geologist.

COMMENTS: Comments on the drilling.

COMPANYHOLENAME: Alternative borehole name given by the drilling company, e.g BH 5, TW 2. Varchar2 (50).

GSIHOLENAME: combination of the 1:25,000 sheet Number and a three-digit reference number. Varchar2 (30).

INVTYPE : Drilling Type. Varchar2 (10).

OWNER: Field to differentiate between inputting GSI section (Groundwater, etc.)/ Varchar2 (15).

EDITBY: Last person who edited data in the database. Varchar2 (15)

EDITDATE: Last time data was edited/. Date ().

DATUM: Type of datum is being used to correct ground elevation.

SURFACEOFFSET:

LOGTOP: Ground elevation of the borehole O.D.Malin.

DATAENTERED: Last person who edited data in the database. Varchar2 (15).

REDUCEDBASE.-? Reduced level-top .O.D.Malin.

DATAENTERED.- Last person who edited data in the database. Varchar2 (15).

LAYERID Layer identification number.

TEXTURE. Texture of the lithology.

COLOUR. Colour of lithology

MAJOR LITH.- Primary constituents within the lithology.

MINOR LITH. Secondary constituents on that particularly lithology.

LESSER LITH Other constituents less abundant within the lithology.

STRENGTH.- strength of the lithology.i.e. Dense coarse, firm to stiff.

GEN LITH.- Lithological genetic group.i.e. gabre, dunite

GEOLOGICAL INTERPRETATION.- geological interpretation.

LAYERTOP. Top depth of the layer.

LAYERBOTTOM. Bottom depth of the layer.

THICNESS. Difference between the top depth and bottom depth of the layer.

STRATNAME Name of the stratigraphic unit where the borehole in.i.e. “ Achill Head Formation”

OTHER PHYSICAL CHARACTERISTICS. . Comments on physical characteristics.

LAYERCOMM: -Comments on lithology, layer.

DEPTH TO BASE.- base depth of the layer.

TESTID.- Test number.

TESTCLASS.- test class (Field labsoil, labrock and labwater)

TESTTYPE.- Type of test i.e. Standard Penetration Test.

TOP.- Top depth of the test.

BOTTOM.- bottom depth of the test.

PROPERTY.- Property is being measured.

RESULTCOMMENTS.- comments on results.

RESULT.- Test results. NUMBER (10, 0).

UNITS. Test results units.i.e. Nblow, % pass, N/m(2).

SAMPLE TYPE: Sample type taken during the test.i.e: Bulk disturbed sample, black sample, CBR Mould sample)

ROW OWNER. Field to differentiate between inputting GSI section (Geotechnics, etc.)/ Varchar2 (15).

7.Geographical information

Reference system : Irish National Grid

West longitude: 20,000E

East longitude: 340,000E

North latitude: 460,000N

South latitude: 20,000N

Spatial Extent : Whole of Republic of Ireland

Additional extent:

Scale : 1:50,000 and 1:5,000 maps using for digitizing boreholes.

8.Distribution Information

Filename : GSI_Bedrock Boreholes

Holder : Geological Survey of Ireland.

Distributor contract details : Koen Verbruggen

Principal Geologist

Geological Survey of Ireland,

Beggar's Bush,

Haddington Road ,

Dublin 4

gsisales@gsi.ie

Storage Format : Oracle database, Excel, ArcGIS

Supply Format : MS Access, MS Excel.

Supply media : CD-Rom and paper print out.

File size : 23.6 MB

Copyright : Use of the data are constrained only by the GSI GIS Data License Agreement

Other Restrictions : Charging, Some Info Confidential.

9.Quality Ratings

Spatial Accuracy : All boreholes have a grid co ord. (Grid coordinates are 5 figure), i.e. must be multiplied by 10 to enable use in GIS.

Thematic accuracy : Correct description of borehole log using the various lookup lists.

Currency: Information currently available

Logical consistency : Fields filled in correctly so that there are no inconsistencies when output in a GIS format.