BGS Rock Classification Scheme
Lime-pseudosparstone - A type of limestone, classified on the basis of its diagenetic texture. It is a limestone composed almost totally of a divergent radial fibrous calcite cement in which grains or in-situ biogenic material do not constitute a framework. The calcite pseudospar occurs as in-situ botryoidal masses commonly found in the core of algal mounds and probably formed from early diagenetic alteration of aragonite masses. The diagenetic process does not cause any alteration to the depositional or biological texture. British Geological Survey Research Report RR/99/03, section 3.1, table 3 and fig. 6.
| Code | LMPSST |
|---|---|
| Description | Lime-pseudosparstone - A type of limestone, classified on the basis of its diagenetic texture. It is a limestone composed almost totally of a divergent radial fibrous calcite cement in which grains or in-situ biogenic material do not constitute a framework. The calcite pseudospar occurs as in-situ botryoidal masses commonly found in the core of algal mounds and probably formed from early diagenetic alteration of aragonite masses. The diagenetic process does not cause any alteration to the depositional or biological texture. British Geological Survey Research Report RR/99/03, section 3.1, table 3 and fig. 6. |
| Qualifiers | No qualifiers currently exist. |
| Definition | Sedimentary rock, crystals >50% calcite/aragonite. Petrological study shows non-obliterative insitu botryoidal calcite pseudospar masses. No framework of grains/biogenic material. Radial fibrous calcite cement. Cementstone |
| Linked data | http://data.bgs.ac.uk/id/EarthMaterialClass/RockName/LMPSST |
CAVEAT
"Thumbnail" definitions attached to some of the table entries are an interim attempt to provide simple short descriptions of the "unqualified" rock types presented within the BGS Rock Classification Scheme. Every effort has been made to ensure accuracy and consistency but minor contradictions or omissions might be present. The BGS welcomes any feedback pointing out such minor imperfections and/or providing constructive comment and suggestions for improvement of the definitions. In the first instance such feedback should be directed to Dr Tim McCormick.