Appin Group

For the American company, see Arpin Group.

Appin Group
Stratigraphic range: Neoproterozoic
Type	Group
Unit of	Dalradian Supergroup
Sub-units	Lochaber, Ballachulish and Blair Atholl subgroups
Underlies	Argyll Group
Overlies	Grampian Group
Thickness	up to 4km
Lithology
Primary	psammite
Other	semipelite, quartzite, pelite, schist, limestone, slate
Location
Region	Central Highlands
Type section
Named for	Appin

The Appin Group is a thick sequence of metamorphosed Neoproterozoic sedimentary rocks that outcrop across the Central Highlands of Scotland, east of the Great Glen. It forms a part of the Dalradian Supergroup.

It is divided into three subgroups each consisting of multiple named formations. In stratigraphic order i.e. youngest at the top, these are:

Blair Atholl Subgroup

Islay Limestone Formation

Mullach Dubh Phyllites Formation

Lismore Limestone Formation

Cuil Bay Slates Formation

Ballachulish Subgroup

Appin Phyllite & Limestone Formation

Appin Quartzite Formation

Ballachulish Slate Formation

Ballachulish Limestone Formation

Lochaber Subgroup

Leven Schist Formation

Glencoe Quartzite Formation

Binnein Schist Formation

Binnein Quartzite Formation

Eilde Schist Formation

Eilde Quartzite Formation

This whole succession reflects alternate periods of deepening and filling of the sedimentary basin.