Identification

Title

BGS Permeability Index version 8

Abstract

The BGS Permeability Index dataset shows estimated rates of water movement from the ground surface to the water table. The v8 dataset incorporates the latest geology mapping (BGS Geology 50k). This includes updates to the lithology-coding schema, the LEX_RCS. A 2-part code used to identify the named rock unit from the BGS lexicon of named rock units (LEX) followed by a Rock Classification Scheme (RCS) code which describes the rocks lithological characteristics e.g. texture and composition. Updates to these codes and latest dissolution hazard data sourced from BGS GeoSure: Soluble Rocks have been reviewed and classified as part of the version 8 release. The dataset covers Great Britain and is presented at a scale of 1:50 000, based on the geological data at the same scale. However, in areas where the geology is not mapped to this scale, the next best available scale is used. The BGS Permeability Index can be used to compare the relative permeability of deposits at the regional scale, indicating where highly permeable rocks could allow rapid infiltration to occur, or where less permeable rocks are present and water could pond on the ground surface. The dataset can be used as a component in a wide range of geo-environmental assessments such as natural flood management, Sustainable Drainage Systems, engineering desk studies, slope stability, and aquifer vulnerability. It is for use at the regional scale and is not recommended for use at the site-specific scale.

Resource type

dataset

Resource locator

https://www.bgs.ac.uk/datasets/permeability/

name: BGS Datasets - Permeability Homepage

function: order

https://doi.org/10.5285/7f9c6bb5-1e7a-4405-ae59-d893a80df2b3

name: Digital Object Identifier (DOI)

function: information

Unique resource identifier

code

http://data.bgs.ac.uk/id/dataHolding/13607706

codeSpace

Dataset language

eng

Spatial reference system

code identifying the spatial reference system

Classification of spatial data and services

Topic category

geoscientificInformation

Keywords

Keyword set

keyword value

originating controlled vocabulary

title

reference date

date type

publication

effective date

2008-06-01

Keyword set

keyword value

Ground water movement

Hydrogeology

Permeability

originating controlled vocabulary

title

reference date

date type

revision

effective date

2011

Keyword set

keyword value

NERC_DDC

Geographic location

West bounding longitude

-8.3400

East bounding longitude

2.6900

North bounding latitude

60.8600

South bounding latitude

49.8400

Extent

Extent group

authority code

title

reference date

date type

revision

effective date

2009

code identifying the extent

GBN

Extent group

authority code

title

reference date

date type

creation

effective date

1979

code identifying the extent

GREAT BRITAIN [id=139600]

Temporal reference

Temporal extent

Begin position

1879

End position

2021

Dataset reference date

date type

creation

effective date

2021-01-07

Frequency of update

unknown

Quality and validity

Lineage

The BGS Permeability Index dataset V8 is derived from the 4 geological themes of BGS Geology 50k: mass-movement, artificial, superficial deposits and bedrock. Each polygon in the BGS Geology 50k is attributed with a 2-part code; LEX-RCS code (rock unit-lithology combination). The LEX-RCS code is assigned (attributed) with 3 further codes to indicate the Predominant Flow Mechanism, and the Maximum and Minimum Permeability. The dataset was produced by dissolving the individual themes of BGS Geology 50k based on LEX-RCS and joining to a Microsoft Access lookup table of all the LEX-RCS combinations with their assigned permeability codes. The first code 'Predominant Flow Mechanism' indicates how fluid will migrate from the ground surface through the unsaturated zone of each rock unit and lithology combination and has three classes: Intergranular, Fracture or Mixed (intergranular and fracture). The second and third codes (Maximum and Minimum Permeability) indicate the range of flow rates likely to be encountered in the unsaturated zone for each rock unit and lithology combination to which five classes have been assigned for the Maximum and Minimum Permeability codes: very high, high, moderate, low, and very low. The Maximum and Minimum Permeability values represent a likely permeability range for the specified rock unit and lithology combination at, and immediately below, its outcrop or subcrop (rather than at any significant depth). The Maximum Permeability represents the fastest potential vertical rate of migration through the unsaturated zone likely to be encountered in the specified rock unit-lithology combination. The Minimum Permeability represents the minimum, and in some cases more normal, bulk rate of vertical movement likely to be encountered. Where a widely variable combination of lithologies occurs within a rock unit this Minimum Permeability value reflects the probable movement rate likely to be encountered in the least permeable horizons. These 3 codes were ascribed solely on the known hydrogeological characteristics of the various lithologies, considering their age, dissolution potential, degree of cementation/induration and fracturing. In unconsolidated deposits, intergranular flow is the predominant flow mechanism. In most consolidated sedimentary rocks, and igneous and metamorphic rocks, fracture flow will occur and hence a wide range of permeability values can occur for any one lithology. The potential for dissolution and degree of cementation, lithological variation and induration are also factors that affect measured values.

Conformity

Conformity report

specification

title

reference date

date type

publication

effective date

2011

degree

false

explanation

See the referenced specification

Conformity report

specification

title

reference date

date type

publication

effective date

2010-12-08

degree

false

explanation

See http://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=OJ:L:2010:323:0011:0102:EN:PDF

Data format

name of format

ESRI Shapefile

version of format

Not enterd

Constraints related to access and use

Constraint set

Limitations on public access

Constraint set

Limitations on public access

The copyright of materials derived from the British Geological Survey's work is vested in the Natural Environment Research Council [NERC]. No part of this work may be reproduced or transmitted in any form or by any means, or stored in a retrieval system of any nature, without the prior permission of the copyright holder, via the BGS Intellectual Property Rights Manager. Use by customers of information provided by the BGS, is at the customer's own risk. In view of the disparate sources of information at BGS's disposal, including such material donated to BGS, that BGS accepts in good faith as being accurate, the Natural Environment Research Council (NERC) gives no warranty, expressed or implied, as to the quality or accuracy of the information supplied, or to the information's suitability for any use. NERC/BGS accepts no liability whatever in respect of loss, damage, injury or other occurence however caused.

Responsible organisations

Responsible party

organisation name

British Geological Survey

full postal address

Environmental Science Centre, Nicker Hill, Keyworth

NOTTINGHAM

NG12 5GG

United Kingdom

telephone number

0115 936 3143

facsimile number

0115 936 3276

email address

enquiries@bgs.ac.uk

responsible party role

distributor

Responsible party

organisation name

British Geological Survey

full postal address

Environmental Science Centre, Nicker Hill, Keyworth

NOTTINGHAM

NG12 5GG

United Kingdom

telephone number

0115 936 3143

facsimile number

0115 936 3276

email address

enquiries@bgs.ac.uk

responsible party role

originator

Responsible party

organisation name

British Geological Survey

full postal address

Maclean Building, Crowmarsh Gifford

WALLINGFORD

OX10 8BB

United Kingdom

telephone number

01491 838800

facsimile number

01491 692345

email address

enquiries@bgs.ac.uk

responsible party role

distributor

Responsible party

organisation name

British Geological Survey

full postal address

Maclean Building, Crowmarsh Gifford

WALLINGFORD

OX10 8BB

United Kingdom

telephone number

01491 838800

facsimile number

01491 692345

email address

enquiries@bgs.ac.uk

responsible party role

originator

Responsible party

organisation name

British Geological Survey

email address

not available

responsible party role

distributor

Responsible party

organisation name

British Geological Survey

email address

not available

responsible party role

pointOfContact

Metadata on metadata

Metadata point of contact

organisation name

British Geological Survey

full postal address

Environmental Science Centre, Keyworth

NOTTINGHAM

NG12 5GG

United Kingdom

telephone number

+44 115 936 3100

email address

enquiries@bgs.ac.uk

responsible party role

pointOfContact

Metadata date

2022-06-28

Metadata language