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Survey Details for CRMRTGL268 - 2026-06-06

CRMRTGL268

Geological Landscape

Afon Morlais

Carmarthenshire

2008-12-30

  • Level 1: Lowland hills and valleys
  • Level 2: Lowland river and drainage systems
  • Level 3: Active lowland river-flood plain system

Monitoring

Q1 - Date of monitoring?

  • No Answer

Q1a - Monitoring undertaken by

  • No Answer

Q1b - Has this record been updated following monitoring work?

  • No Answer

Q1c - Change indicated by

  • No Answer

Q1d - What has changed?

  • No Answer

Q1e - Has the information ever been verified in the field?

  • No

Q2 - Does this area have a special or functional link with an adjacent area?

  • No

Description

Q3 - If Classification is "Other", specify here

  • Empty value

Q4 - What is the geographical and topographical character of this area?

  • Narrow floodplain-channel system between near Llannon and Llanger of SSE flowing river system, draining the top of the Upper Carboniferous 'Coal Measures' sandstone escarpment of the Tumble, etc area. Includes a narrow section in the Gelli-wen area where no signifcant alluvium is present (cuts through bedrock??).

Q4a - Where bedrock dominated, what is the dominant bedrock type?

  • No Answer

Q4b - Where bedrock dominated, what is the age that characterises the aspect area?

  • No Answer

Q4c - Where bedrock dominated, what is the major rock lithogy (-ies)?

  • No Answer

Q4d - Where drift dominated, what is the dominant drift deposit?

  • Fluvial

Q4e - Where drift dominated, what is the major sediment that characterises the area?

  • Silt

Q5 - What is the characteristic Level 3 component of the area?

  • Active lowland river-flood plain system

Q6 - Which of the following is a significant contributor to the geological character of the area?

  • Stratigraphic formation(s)
    • Possible minor Warwickshire Group: Pennant Sandstone Formation (=South Wales Pennant Formation / 'Upper Coal Measures'.) [CARBONIFEROUS, PENNSYLVANIAN: 'WESTPHALIAN'], 'Lower Pennant Measures' in N [BOLSOVIAN].
  • Superficial deposits
    • Fluvial deposits: active floodplain alluvium, probably also minor low terrace deposits [QUATERNARY: HOLOCENE].
  • Active processes
    • Fluvial

Q7 - What additional subsidiary Level 3 components are notable?

  • No Answer

Q8 - What Level 4 components are notable in this area?

  • River channel (natural)
  • Flood plain

Q9 - What active geological and geomorphological processes are significant in this area?

  • Fluvial
  • Empty value

Q10 - Are there components of significant hydrological importance?

  • Yes
    • Fluvial

Q11 - Are there any pedological processes that are significant in the area or have had a landscape forming effect?

  • No

Q12 - Is there current mineral extraction?

  • No

Q13 - Has there been mineral extraction in the past?

  • Not known

Q14 - Are there SSSI/GCR sites here?

  • No

Q15 - Are there geological SINC, 2nd tier, or RIGS sites in the area?

  • No

Condition

Q16 - Value

  • Moderate
    • No regionally significant sites/ landforms noted during present survey and geology/ geomorphology considered to be typical of feature/ process and is either widespread, better exposed elsewhere or not currently known to be exceptional.

Q17 - Condition

  • Good
    • Rural area with no significant development.

Q18 - Trend

  • Constant
    • Rural area with no significant development.

Recommendations

Q19 - Existing management

  • Generally Appropriate

Q20 - Existing management remarks:

  • Rural area with no significant development.

Q21 - Principal management recommendations

  • Ensure that no features or natural systems of geological or geomorphological significance in the area are lost or damaged (e.g. due to development or forestry). Complete RIGS survey of Coalfield area (including Devonian-Carboniferous successions) and ensure that selected sites are safeguarded using Local Plan policies and constraint mapping.

Q22 - Guideline

  • Long Term
    • Ensure that no features or natural systems of geological or geomorphological significance in the area are lost or damaged (e.g. due to development or forestry).
  • Medium Term
    • Complete RIGS survey of Coalfield area (including Devonian-Carboniferous successions) and ensure that selected sites are safeguarded using Local Plan policies and constraint mapping.

Tolerance To Change

Q23 - Are there any significant threats to the current integrity and condition of the Earth Heritage features of the area?

  • Not known

Aspect Area Boundary

Q24 - To what level was this information site-surveyed?

  • Level 3

Q25 - At 1:10,000, how much of the Aspect Area boundary is precise?

  • Most
    • Aspect Area boundaries surveyed at 1:10,000 using aerial photographs, mapped at 1:25,000.

Q26 - What baseline information source was used for Aspect Area boundary mapping?

  • Other
    • 1:50,000 British Geological Survey maps, 1:10,000 aerial photographs (as stereo pairs), OS 1:25,000 Landranger topographical maps.

Q27 - If OS Data was used, what was the scale?

  • 1:25,000

Q28 - What is the justification for the Aspect Area boundaries?

  • Break of slope at edge river floodplain / terrace/ drift filled valley systems

Evaluation

Q29 - Evaluation Criteria: Research Value

  • Moderate
    • No regionally significant sites/ landforms noted during present survey and geology/ geomorphology considered to be typical of feature/ process and is either widespread, better exposed elsewhere or not currently known to be exceptional.

Q29a - Evaluation Criteria: Educational Value

  • Moderate
    • No regionally significant sites/ landforms noted during present survey and geology/ geomorphology considered to be typical of feature/ process and is either widespread, better exposed elsewhere or not currently known to be exceptional.

Q30 - Evaluation Criteria: Historical Value

  • Moderate
    • No regionally significant sites/ landforms noted during present survey and geology/ geomorphology considered to be typical of feature/ process and is either widespread, better exposed elsewhere or not currently known to be exceptional.

Q31 - Evaluation Criteria: Rarity / Uniqueness

  • Moderate
    • No regionally significant sites/ landforms noted during present survey and geology/ geomorphology considered to be typical of feature/ process and is either widespread, better exposed elsewhere or not currently known to be exceptional.

Q32 - Evaluation Criteria: Classic Example

  • Moderate
    • No regionally significant sites/ landforms noted during present survey and geology/ geomorphology considered to be typical of feature/ process and is either widespread, better exposed elsewhere or not currently known to be exceptional.

Q33 - Evaluation Criteria: Overall Evaluation

  • Moderate
    • No regionally significant sites/ landforms noted during present survey and geology/ geomorphology considered to be typical of feature/ process and is either widespread, better exposed elsewhere or not currently known to be exceptional.

Q34 - Justification of overall evaluation

  • No regionally significant sites/ landforms noted during present survey and geology/ geomorphology considered to be typical of feature/ process and is either widespread, better exposed elsewhere or not currently known to be exceptional.

Bibliography

Q35 - Sources and additional assessments

  • ORDNANCE SURVEY 1998b, Explorer Map 178 (1:25, 000). INSTITUTE OF GEOLOGICAL SCIENCES 1977, Sheet 230 (Drift), 1:50,000 Geological Series; ARCHER, A.A. 1968, Memoir of the Geological Survey of Great Britain (England and Wales), (Sheets 229 pt, 230, 246), HMSO. STRAHAN, A. et al. 1907, Memoirs of the Geological Survey (England and Wales), HMSO;

Assessment

Q36 - Additional Assessments

  • None

Q37 - Additional Comments

  • Additional Level 4 features include: Meander