In engineering terms, all materials deposited as a result of glacial and periglacial processes are transported soils. Many of these deposits have engineering characteristics that differ from those of water-lain sediments. In the UK, the most extensive glacial and periglacial deposits are tills. Previously, engineering geologists have classified them geotechnically as Lodgement, Melt-out, Flow and Deformation Tills or as variants of these. However, in this book, tills have been reclassified as: subglacial traction till, glacitectonite and supraglacial mass flow diamicton/glaciogenic debris flow deposits (see Chapter 4 Sections 4.1-4.3). Because this classification is new, it is not possible to relate geotechnical properties and characteristics to the subdivisions of the new classification. Consequently, the domain/stratigraphic classification, recently developed by the British Geological Survey and others, has been used and their geotechnical properties and characteristics are discussed on this basis. The geotechnical properties and characteristics of the other main glacial and periglacial deposits are also discussed. For some of these (for example, glaciolacustrine deposits, quick clays and loess), geohazards relating to the lithology and/or fabric of the deposit are discussed along with their properties. Other geohazards that do not relate to lithology and/or fabric are discussed separately as either local geohazards or regional ones. In some cases (for example, glaciofluvial sands and gravels), the geotechnical properties and behaviour are similar to sediments deposited under different climatic conditions. Consequently, these deposits are not discussed at length. Similarly, some of the local geohazards that are found associated with glacial and periglacial deposits relate to current climatic conditions and are not discussed here. Examples include landsliding and highly compressible organic soils (peats). geographical location and description. This means that some of the data in the literature can be attributed to the new stratigraphical till units. Examples of this are discussed below. Further, it should be noted that in Chapter 4 Section 4.6 it is demonstrated how the landsystem approach can be reconciled with the domains approach of McMillan et al. (2011) and McMillan & Merritt (2012). As the geotechnical property information from the NGPD, some of which is summarised here, is classified in terms of domains, it is proposed that, in the longer term, the landsystem/domain approach should supersede the till classifications used by Trenter (1999) and Clarke (2012). 6.2.1.2 Glacial till stratigraphy 6.2.1.2.1 Glacial tills on the geological map During the desk study stage of a site investigation some of the initial geological information comes from the relevant geological map. In the UK, the geological maps used (published by the BGS) are at 1:50,000 or 1:10,000 scale. A broad overview of the national extent of glacial tills in the UK can be obtained from the engineering geology maps produced at a scale of 1:1,000...
