The BGS Lexicon of Named Rock Units — Result Details
Morvern Greensand Formation
| Computer Code: | MOGR | Preferred Map Code: | MoGr |
|---|---|---|---|
| Status Code: | Full | ||
| Age range: | Cenomanian Age (KE) — Cenomanian Age (KE) | ||
| Lithological Description: | Glauconitic calcareous sandstone, white to pale greenish. Some gritty beds and calcareous inclusions up to cobble size. Conspicuously shelly (mainly oysters) in parts. | ||
| Definition of Lower Boundary: | The lower boundary is unconformable on various Jurassic and Triassic strata. | ||
| Definition of Upper Boundary: | The upper boundary is at a [?]conformable contact with the overlying Lochaline White Sandstone Formation. However Braley (1990) and Lowden et al. (1992) regarded the Lochaline White Sandstone Formation as a member within this formation and considered the upper boundary as unconformable with the Gribun Chalk Formation. | ||
| Thickness: | 0.3 to 13.4m, according to Rawson et al. (1978). | ||
| Geographical Limits: | Known from the Morvern district and the Isle of Mull. | ||
| Parent Unit: | Inner Hebrides Group (IHEB) | ||
| Previous Name(s): | Cenomanian Greensand [Obsolete Name and Code: Use MOGR]
(-1706)
Greensand Of Morvern [Obsolete Name And Code: Use MOGR] (GSM) |
||
| Alternative Name(s): | none recorded or not applicable | ||
| Stratotypes: | |||
| Reference Section | Alt na Teangaigh, Isle of Mull. Stream section showing attenuated succession. Mortimore et al., 2001. | ||
| Reference Section | Auchnacraig Cliff (Braley, 1990) Two section showing slightly different lithstratigraphical relationship [see Mortimore et al., 2001]. | ||
| Type Section | Beinn Iadain In Braley (1990) two sections given on Beinn Iadain as [NM 6917 5490 and NM 6965 5645] the former presumed to be the section described in Judd (1878) and Lee and Bailey (1925). Mortimore et al. (2001) give their locality as Beinn Iadain, Morvern [NM 670 541 to NM 689 528] and also a site called Beinn na H-Uamha at [NM 68]. | ||
| Reference(s): | |||
| Lee, G W and Pringle, J. 1932. A synopsis of the Mesozoic rocks of Scotland. Transactions of the Geological Society of Glasgow, Vol.19, 158-224. | |||
| Lowden, B, Braley, S, Hurst, A and Lewis, J, 1992. Sedimentological studies of the Cretaceous Lochaline Sandstone, NW Scotland. 159-162 in Parnell, J (editor), Basins on the Atlantic Seaboard: Petroleum Geology, Sedimentology and Basin Evolution. Geological Society of London Special Publication, No.62. | |||
| Mortimore, R N, Wood, C J and Gallois, R W, 2001. British Upper Cretaceous Stratigraphy. Geological Conservation Review Series. No. 23. (Peterborough: Joint Nature Conservation Committee.) | |||
| Judd, J W. 1878. The secondary rocks of Scotland. Third paper. The strata of the Western Coast and Islands. With a note on the foraminifera and other organisms in the Chalk of the Hebrides by T R Jones. Quarterly Journal of the Geological Society of London, Vol.34, 600-743. | |||
| Waters, C N, Gillespie, M R, Smith, K, Auton, C A, Floyd, J D, Leslie, A G, Millward, D, Mitchell, W I, McMillan, A A, Stone, P, Barron, A J M, Dean, M T, Hopson, P M, Krabbendam, M, Browne, M A E, Stephenson, D, Akhurst, M C, and Barnes, R P. 2007. Stratigraphical Chart of the United Kingdom: Northern Britain. (British Geological Survey.) | |||
| Lee, G W and Bailey, E B. 1925. The pre-Tertiary Geology of Mull, Loch Aline and Oban. Memoir of the Geological Survey of Great Britain, parts of Sheets 35, 43, 44, 45 and 52 (Scotland). | |||
| Braley, S M. 1990. The Sedimentology, Palaeoecology and Stratigraphy of Cretaceous Rocks in N.W. Scotland. Unpublished PhD Thesis CNAA, Polytechnic SouthWest (now University), Plymouth. | |||
| Rawson, P F, Curry, D, Dilley, F C, Hancock, J M, Kennedy, W J, Neale, J W, Wood, C J and Worrsam, B C. 1978. A correlation of Cretaceous rocks in the British Isles. Geological Society of London, Special Report No.9. | |||
| 1:50K maps on which the lithostratigraphical unit is found, and map code used: | |||
| S043 S043 S044 S044 S052 S070 S081 | |||