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Primary survey of the Aberfoyle district was undertaken from 1871 to 1899. The first edition of Sheet 38 (solid only) was published at 1:63 360 scale in 1901. Although no memoir was published for this sheet, a draft was prepared by Cunningham-Craig in 1901 and is available as a BGS technical report (Cunningham-Craig, 2000<ref name="Cunningham-Craig 2000">Cunningham-Craig, E H. 2000. Explanation of Sheet 38, Loch Lomond. [1901]. ''British Geological Survey Technical Report'', WO/00/05.</ref>). In addition, several references are made to aspects of Dalradian stratigraphy and structure and the problematical status of the Highland Border Complex in the Annual Reports of the Director of the Geological Survey of 1895 to 1899, copies of which are held in the BGS library in Murchison House and Keyworth.

Much research has concentrated on the structure and stratigraphy of the Dalradian in the Aberfoyle district. Nicol (1863) first recognised the Highland Boundary Fault as a major structure separating the Highlands from the Midland Valley of Scotland. Henderson (1938)<ref name="Henderson 1938">Henderson, S M K. 1938. The Dalradian succession of the Southern Highlands. ''Report of the Annual Meeting of the British Association for the Advancement of Science, Cambridge, Sectional Transactions C-Geology'', p. 424.</ref> determined from graded bedding and other evidence that the metasandstones young away from either side of the Aberfoyle Slate Formation, and thus identified the Aberfoyle Anticline. Anderson (1947)<ref name="Anderson 1947">Anderson, J G C. 1947. The geology of the Highland Border: Stonehaven to Arran. ''Transactions of the Royal Society of Edinburgh'', Vol. 61, 479–515.</ref> considered that this structure could be traced along the Highland Border from Edzell to Arran and he interpreted it as an anticline sensu stricto. Subsequently, Shackleton (1957)<ref name="Shackleton 1957">Shackleton, R M. 1957. Downward facing structures in the Highland Border. ''Quarterly Journal of the Geological Society of London'', Vol. 117, 131–157.</ref> showed that the Aberfoyle Anticline was, in fact, a downward-facing (i.e. inverted), synformal anticline, and considered the fold to be the down-folded closure of the regional-scale, recumbent Tay Nappe. Stone (1957)<ref name="Stone 1957">Stone, M. 1957. The Aberfoyle anticline, Callander, Perthshire. ''Geological Magazine'', Vol. 94, 265–276.</ref> mapped out lateral facies changes in the Dalradian near Callander, drawing attention to the apparent asymmetry of the Aberfoyle Anticline. He confirmed that the structure closed downwards and plunged west-south-west. Harris (1962)<ref name="Harris 1962">Harris, A L. 1962. Dalradian geology of the Highland Border near Callander. ''Bulletin of the Geological Survey of Great Britain'', Vol. 19, 1–15.</ref>, working in the SE of the district, suggested that the Aberfoyle Slate might be diachronous, and attributed the increase in outcrop width of slate to the east to facies variations. Harris and Fettes (1972)<ref name="Harris 1972">Harris, A L, and Fettes, D J. 1972. Stratigraphy and structure of Upper Dalradian rocks at the Highland Border. ''Scottish Journal of Geology'', Vol. 8, 253–264.</ref> studied cleavage relationships in the Dalradian along the Highland Border, questioning the correlation of slates and grits in this area. Mendum and Fettes (1985)<ref name="Mendum 1985">Mendum, J R, and Fettes, D J. 1985. The Tay nappe and associated folding in the Ben Ledi-Loch Lomond area. ''Scottish Journal of Geology'', Vol. 21, 41–56.</ref> showed that the nose of the Tay Nappe in the Aberfoyle district consisted of three downward-facing F1 fold closures: the Ben Vane Synform, the synformal Aberfoyle Anticline and the Ben Ledi Antiform. Mendum and Fettes also determined the southern limit of D2 deformation, discussed the relationship of the Highland Border Downbend to D4, and recognised the stratigraphical significance of the Green Beds. Harte et al. (1984)<ref name="Harte 1984">Harte, B, Booth, J E, Dempster, T J, Fettes, D J, Mendum, J R, and Watts, D. 1984. Aspects of the post-depositional evolution of Dalradian Highland Boundary rocks in the Southern Highlands of Scotland. ''Transactions of the Royal Society of Edinburgh, Earth Sciences'', Vol. 75, 151–163.</ref> discussed the nature of the Highland Border Downbend, attributing its formation to block uplift along basement lineaments.

The volcaniclastic sandstone that forms the ‘green beds’ had been recognised as a distinctive lithology by the original surveyors (Pickett et al., 2006<ref name="Pickett 2006">Pickett, E A, Hyslop, E K, and Petterson, M P. 2006. The Green Beds: deposition and origin of a basic igneous-rich sedimentary sequence in the Dalradian Supergroup of Scotland. ''Scottish Journal of Geology'', Vol. 42, 43–57.</ref>). Phillips (1930)<ref name="Phillips 1930">Phillips, F C. 1930. Some mineralogical and chemical changes induced by progressive metamorphism in the Green Bed group of the Scottish Dalradian. ''Mineralogical Magazine'', Vol. 22, 239–256.</ref> demonstrated that they contain a significant basic igneous component, and Roberts (1966)<ref name="Roberts 1966">Roberts, J L. 1966. Sedimentary affiliations and stratigraphic correlation of the Dalradian rocks in the South-west Highlands of Scotland. ''Scottish Journal of Geology'', Vol. 2, 200–223.</ref> and Kamp (1970) recognised from geochemical and petrological data that the green beds comprise a mixture of siliclastic and volcaniclastic sediment. The relationship of the green beds to other expressions of basic magmatism within the Dalradian outcrop is the subject of recent and current research (Pickett, 1997<ref name="Pickett 1997">Pickett, E A. 1997. An introduction to the Green Beds of the Southern Highland Group of the Scottish Dalradian: previous research and an account of preliminary work carried out in 1997. British Geological Survey Technical Report, WA/97/92.</ref>; Hyslop and Pickett, 1998<ref name="Hyslop 1998">Hyslop, E K, and Pickett, E A. 1998. A preliminary study of the petrology of the Green Beds and associated rocks from the Southern Highland Group of the Scottish Dalradian. ''British Geological Survey Technical Report'', WG/98/07.</ref>; Burt, 2002<ref name="Burt 2002">Burt, C E. 2002. Sedimentary environments and basin evolution of the upper Dalradian: Tayvallich Subgroup and Southern Highland Group. Unpublished PhD thesis, Kingston University.</ref>; Pickett et al., in press<ref name="Pickett 2006">Pickett, E A, Hyslop, E K, and Petterson, M P. 2006. The Green Beds: deposition and origin of a basic igneous-rich sedimentary sequence in the Dalradian Supergroup of Scotland. ''Scottish Journal of Geology'', Vol. 42, 43–57.</ref>).

Work on the metamorphism of Dalradian rocks in the Aberfoyle district, has elucidated both the appearance of index minerals in metasedimentary rocks and the progressive changes in mineralogy of volcaniclastic and mafic rocks with increasing metamorphic grade. Tilley (1925)<ref name="Tilley 1925">Tilley, C E. 1925. A preliminary survey of metamorphic zones in the southern Highlands of Scotland. ''Quarterly Journal of the Geological Society of London'', Vol. 81, 100–112.</ref> mapped what he considered to be the garnet isograd in pelitic rocks in the Aberfoyle area. Subsequently, Mather (1970)<ref name="Mather 1970">Mather, J D. 1970. The biotite isograd in the lower greenschist facies rocks of the Dalradian rocks of Scotland. ''Journal of Petrology'', Vol. 11, 253–275.</ref> demonstrated that the incoming of garnet and biotite is dependent on bulk rock composition, and suggested that a more appropriate measure of metamorphic grade in low-grade metasediments is the incompatibility of chlorite and potassium feldspar. Phillips (1930)<ref name="Phillips 1930">Phillips, F C. 1930. Some mineralogical and chemical changes induced by progressive metamorphism in the Green Bed group of the Scottish Dalradian. ''Mineralogical Magazine'', Vol. 22, 239–256.</ref> described mineralogical changes within the Green Beds, whilst Wiseman (1934)<ref name="Wiseman 1934">Wiseman, J D H. 1934. The central and south-west Highland epidiorites: a study in progressive metamorphism. ''Quarterly Journal of the Geological Society of London'', Vol. 90, 354–417.</ref> described progressive metamorphism in metabasic sheets, recognising both bulk compositional and retrograde effects. Van de Kamp (1970)<ref name="Van de Kamp 1970">Van Der Kamp, P C. 1970. The Green Beds of the Scottish Dalradian Series: geochemistry, origin and metamorphism of mafic sediments. ''Journal of Geology'', Vol. 78, 281–303.</ref> noted that amphibole occurrence in Green Beds was related to bulk rock calcium content. Hyslop and Pickett (1997) postulated qualitative changes in metamorphic grade with changing mineralogy of the Green Beds across the Southern Highlands, with the lowest grades near Aberfoyle, but metamorphic conditions in this area are yet to be quantified.

Burt (2002)<ref name="Burt 2002">Burt, C E. 2002. Sedimentary environments and basin evolution of the upper Dalradian: Tayvallich Subgroup and Southern Highland Group. Unpublished PhD thesis, Kingston University.</ref> recently completed the first systematic study of the sedimentology of the Southern Highland Group. Although the investigation extends throughout the length of the Southern Highland Group outcrop, particular use is made of exposed sections in the Aberfoyle district. This work shows that sediment gravity flows (debris flows, turbidity currents) were the key depositional agents within a dominantly passive, rifted-margin setting. Different lithostratigraphical units mapped by the British Geological Survey in the late 1990s reflect deposition in different settings on the continental margin, including ramps, aprons and channel systems.

Rocks assigned to the Highland Border Complex (HBC) in the Aberfoyle district have long been the subject of study. During the original survey, Clough (reported in the Summary of Progress of the Geological Survey, 1896, 1897) considered that the black shales of the Bofrishlie Slate Formation at the Highland border were probably Silurian, but could not detect a structural break between these and the Dalradian metasandstones. Jehu and Campbell (1917)<ref name="Jehu 1917">Jehu, T J, and Campbell, R. 1917. The Highland Border rocks of the Aberfoyle district. ''Transactions of the Royal Society of Edinburgh, Earth Sciences'', Vol. 52.</ref> mapped the HBC outcrop in detail, identifying the presence of serpentinites, and compiled the first HBC lithostratigraphy.

The lithostratigraphical status of the Kelty Water Grit Formation, in which occurs the Leny Limestone, has long been controversial. Pringle (1940)<ref name="Pringle 1940">Pringle, J. 1940. The discovery of Cambrian trilobites in the Highland Border rocks near Callander, Perthshire (Scotland). ''The Advancement of Science'', Vol. 1, 252.</ref> determined that the Leny Limestone is of late early to early mid Cambrian age, based on trilobite fossils. Anderson (1947)<ref name="Anderson 1947">Anderson, J G C. 1947. The geology of the Highland Border: Stonehaven to Arran. ''Transactions of the Royal Society of Edinburgh'', Vol. 61, 479–515. </ref>, Johnson and Harris (1976)<ref name="Johnson 1976">Johnson, M R W, and Harris, A L. 1976. Dalradian–?Arenig relations in parts of the Highland Border, Scotland, and their significance in the chronology of the Caledonian Orogeny. ''Scottish Journal of Geology'', Vol. 3, 1–16.</ref> and Harris (1969)<ref name="Harris 1969">Harris, A L. 1969. The relationships of the Leny Limestone to the Dalradian. ''Scottish Journal of Geology'', Vol. 5, 187–190.</ref> considered there to be structural and stratigraphical continuity of at least part of the HBC with the Dalradian. In contrast, Curry et al. (1984)<ref name="Curry 1984">Curry, G B, Bluck, B J, Burton, C J, Ingham, J K, Siveter, D J, and Williams, A. 1984. Age, evolution and tectonic history of the Highland Border Complex, Scotland. ''Transactions of the Royal Society of Edinburgh, Earth Sciences'', Vol. 75, 113–133.</ref> considered the Leny Limestone to be part of the Highland Border Complex, and exotic to the Dalradian. More recently, detailed mapping by Tanner (1995)<ref name="Tanner 1995">Tanner, P W G. 1995. New evidence that the Lower Cambrian Leny Limestone at Callender, Perthshire, belongs to the Dalradian Supergroup, and a reassessment of the ‘exotic’ status of the Highland Border Complex. ''Geological Magazine'', Vol. 132, 473–483.</ref> has reaffirmed the conclusions of Anderson, Johnson and Harris, showing that the Keltie Water Grit Formation is in stratigraphical and structural continuity with Dalradian rocks. This indicates that Dalradian sedimentation continued into at least the early mid Cambrian.

Henderson and Robertson (1982)<ref name="Henderson 1982">Henderson, W G, and Roberston, A H F. 1982. The Highland Border rocks and their relation to marginal basin development in the Scottish Caledonides. ''Journal of the Geological Society of London'', Vol. 139, 433–450.</ref> described conglomerate with gabbro detritus in the HBC near Aberfoyle. Ikin (1983) presented evidence for spilitisation of mafic rocks in the HBC, and suggested formation within a Cambro-Ordovician marginal basin. Ikin and Harmon (1984)<ref name="Ikin 1984">Ikin, N P, and Harmon, R S. 1984. Tectonic history of the ophiolitic rocks of the Highland Border fracture zone, Scotland; stable isotope evidence from fluid–rock interactions during obduction. ''Tectonophysics'', Vol. 106, 31–48.</ref> supported the view of Henderson and Robertson (1982)<ref name="Henderson 1982">Border rocks and their relation to marginal basin development in the Scottish Caledonides. ''Journal of the Geological Society of London'', Vol. 139, 433–450.</ref> and Robertson and Henderson (1984)<ref name="Robertson 1984">Robertson, A H F, and Henderson, W G. 1984. Geochemical evidence for the origins of igneous and sedimentary rocks of the Highland Border, Scotland. ''Transactions of the Royal Society of Edinburgh, Earth Sciences'', Vol. 75, 135–150.</ref> that mafic and ultramafic rocks in the HBC formed in a marginal oceanic basin, and were juxtaposed against the Dalradian during or prior to Grampian D2 deformation. This tectonic interpretation is disputed by Curry et al. (1984)<ref name="Curry 1984">Curry, G B, Bluck, B J, Burton, C J, Ingham, J K, Siveter, D J, and Williams, A. 1984. Age, evolution and tectonic history of the Highland Border Complex, Scotland. ''Transactions of the Royal Society of Edinburgh, Earth Sciences'', Vol. 75, 113–133.</ref>, Bluck (1985<ref name="Bluck 1985">Bluck, B J. 1985. The Scottish paratectonic Caledonides. ''Scottish Journal of Geology'', Vol. 21, 437–464.</ref>; 1990) and Bluck and Ingham (1997)<ref name="Bluck 1997">Bluck, B J, and Ingham, J K. 1997. The Highland Border Controversy: a discussion of ‘New evidence that the Lower Cambrian Leny Limestone at Callander, Perthshire, belongs to the Dalradian Supergroup, and a reassessment of the ‘exotic status of the Highland Border Complex’: Comment. ''Geological Magazine'', Vol. 134, 363–365.</ref>, who suggested that the HBC is exotic to the Dalradian and was docked after the main (D2) Grampian deformation.

Curry et al. (1982)<ref name="Curry 1982">Curry, G B, Ingham, B K, Bluck, B J, and Willams, A. 1982. The significance of a reliable Ordovician age for some Highland Border rocks in central Scotland. ''Journal of the Geological Society of London'', Vol. 139, 451–454.</ref> reported Ordovician (Arenig to possibly Caradoc/Ashgill) faunas from the HBC. Subsequently, Curry et al. (1984)<ref name="Curry 1984"></ref> divided the HBC into four lithostratigraphical units, ranging in age from early Cambrian to Late Ordovician. They related these units in part to an exotic island arc massif. Ingham et al. (1985)<ref name="Ingham 1985">Ingham, J K, Curry, G B, and Williams, A. 1985. Early Ordovician Dounans Limestone fauna, Highland Border Complex, Scotland. ''Transactions of the Royal Society of Edinburgh, Earth Sciences'', Vol. 76, 481–513.</ref> reported mid Arenig trilobites of North American provenance within the Dounans Limestone near Aberfoyle. Dempster and Bluck (1989)<ref name="Dempster 1989">Dempster, T J, and Bluck, B J. 1989. The age and origin of boulders in the Highland Border Complex; constraints on terrane movements. ''Journal of the Geological Society of London'', Vol. 146, 377–379.</ref> presented evidence for mid Proterozoic metasedimentary boulders of possibly exotic provenance within the HBC. Debate continues over the origin and tectonic relationship of the HBC and the age of the Grampian Orogeny. Bluck and Ingham (1997)<ref name="Bluck 1997"></ref> interpret the HBC as a far-travelled exotic unit, emplaced against the Dalradian after the Grampian Orogeny, possibly in Devonian times. Conversely, Tanner et al. (1997)<ref name="Tanner 1997">Tanner, P W G, Dempster, T J, and Rogers, G. 1997. New constraints upon the structural and isotopic age of the Oughterard Granite, and on the timing of events in the Dalradian rocks of Connemara, western Ireland. ''Geological Journal'', Vol. 32, 247–263.</ref> argue that although some of the complex is exotic, and of probable island arc origin, the HBC docked with the Dalradian in the Early Ordovician during the Grampian Orogeny.

Du Toit (1905)<ref name="Du Toit 1905">Du Toit, A L. 1905. The Lower Old Red Sandstone rocks of the Balmaha–Aberfoyle region. ''Transaction of the Edinburgh Geological Society'', Vol. 8, 315–325.</ref> described the Lower Old Red Sandstone of the Balmaha–Aberfoyle area. Wilson (1971<ref name="Wilson 1971">Wilson, A C. 1971. Lower Devonian sedimentation in the north-west Midland Valley of Scotland. Unpublished PhD thesis, University of Glasgow.</ref>, 1980<ref name="Wilson 1980">Wilson, A C. 1980. The Devonian sedimentation and tectonism of a rapidly subsiding, semi-arid fluvial basin in the Midland Valley of Scotland. ''Scottish Journal of Geology'', Vol. 16, 291–313.</ref>) suggested that the Lower Old Red Sandstone in the western Midland Valley was deposited in a rapidly subsiding semi-arid fluvial basin. Read and Johnson (1967)<ref name="Read 1967">Read, W A, and Johnson, S R H. 1967. The sedimentology of sandstone formations within the Upper Old Red Sandstone and lowest Calciferous Sandstone Measures west of Stirling, Scotland. ''Scottish Journal of Geology'', Vol. 3, 242–267.</ref> and Bluck (1978)<ref name="Bluck 1978">Bluck, B J. 1978. Sedimentation in a late orogenic basin: the Old Red Sandstone of the Midland Valley of Scotland. 249–278 in crustal evolution in northwestern Britain. Bowes, D R, and Leake, B E (editors). ''Special Issue of the Geological Journal'', No. 10. </ref> suggested that Upper Devonian fluvial sedimentation in the Midland Valley occurred in an east-north-east trending basin, with eastward flowing rivers and Hall and Chisholm (1987)<ref name="Hall 1987">Hall, I H S, and Chisholm, J I. 1987. Aeolian sediments in the late Devonian of the Scottish Midland Valley. ''Scottish Journal of Geology'', Vol. 23, 203–208.</ref> described Upper Devonian aeolian sedimentation along the axis of the main basin. Phillips and Aitken (1998)<ref name="Phillips 1998">Phillips, E R, and Aitken, A M. 1998. The petrology and composition of the Lower Old Red Sandstone exposed in the Aberfoyle area (Sheet 38E), central Scotland. ''British Geological Survey Technical Report'', WG/98/10.</ref> attributed sedimentary provenance of the [Old Red Sandstone] of the Aberfoyle district to both penecontemporaneous volcanics and the southern Dalradian. Jack and Etheridge (1877)<ref name="Jack 1877">Jack, R L, and Etheridge, R. 1877. On the discovery of plants in the Lower Old Red Sandstone of the neighbourhood of Callander. ''Quarterly Journal of the Geological Society of London'', Vol. 33, 212–222.</ref> described fossil plants from the Dalmary Sandstone Member near Callander, and Henderson (1932)<ref name="Henderson 1932">Henderson, S M K. 1932. Notes on Lower Old Red Sandstone plants from Callander. ''Transactions of the Royal Society of Edinburgh'', Vol. 57, 277–285.</ref> described a similar flora from Thornhill. Owens and Richardson (1972)<ref name="Owens 1972">Owens, B, and Richardson, J B. 1972. Some recent advances in Devonian palynology—review. Compte Rendu 7e Congrès International de Stratigraphie et de Geologie du Carbonifère, Krefeld, Vol. 1, 325–343.</ref> considered this flora to be of early Emsian age.

Read and Johnston (1967)<ref name="Read 1967"></ref> discussed deposition of the lower Carboniferous Inverclyde Group in a range of fluviatile environments, with current directions to the south-south-east. Macro- and microfossils in the lower parts of the Kinnesswood Formation in Dumbartonshire indicate that the lowermost rocks of this formation are of Famennian (latest Devonian) age (Aspen, 1974<ref name="Aspen 1974">Aspen, P. 1974. Fish and trace fossils from the Upper Old Red Sandstone of Dunbartonshire. ''Proceedings of the Geological Society of Glasgow'', Vol. 113, 4–7.</ref>; McNestry, 1993<ref name="McNestry 1993">McNestry, A. 1993. Palynology Report on 18 samples from 1:50k Sheet 15W: New Cumnock. ''British Geological Survey Technical Report'', WH/93/335R.</ref>; Turner, 1994<ref name="Turner 1994">Turner, N. 1994. Palynology of Devonian and Carboniferous rocks of the Cumnock and Doon Valley District, Strathclyde. ''British Geological Survey Technical Report'', WH/94/294R.</ref>). The stratigraphy of the lower Carboniferous Inverclyde Group is described in Browne et al. (1996). General descriptions of the stratigraphy of Lower Devonian, Upper Devonian and lower Carboniferous rocks of the Midland Valley, which outcrop on Sheet 38E, are presented in the memoirs for the adjacent districts, Sheet 39 (Francis et al., 1970<ref name="Francis 1970">Francis, E H, Forsyth, I H, Read, W A, and Armstrong, M. 1970. The geology of the Stirling district. ''Memoir of the Geological Survey of Great Britain'', Sheet 39 (Scotland)).</ref> and Sheet 30W (Paterson et al., 1990<ref name="Paterson 1990">Paterson, I B, Hall, I H S, and Stephenson, D. 1990. Geology of the Greenock district. ''Memoir of the British Geological Survey'', Sheet 30 and part of 29E (Scotland).</ref>).

Simpson (1933)<ref name="Simpson 1933">Simpson, J B. 1933. The late-glacial readvance moraines of the Highland Border west of the River Tay. ''Transactions of the Royal Society of Edinburgh'', Vol. 57, 633–646.</ref> described moraines from the Highland border west of the Tay, which he related to a late glacial re-advance. Thompson (1972)<ref name="Thompson 1972">Thompson, K S R. 1972. The last glaciers in western Perthshire. Unpublished PhD thesis, University of Edinburgh.</ref> described a terminal moraine relating to the Loch Lomond Stadial (11 000–10 000 years BP) near Callander, and Rose (1981)<ref name="Rose 1981">Rose, J. 1981. Field guide to the Quaternary geology of the southeastern part of the Loch Lomond basin. ''Proceedings of the Geological Society of Glasgow'', Vol. 113, 361–392.</ref> described the terminal moraine of the Loch Lomond Glacier of this stadial. Price (1983)<ref name="Price 1983">Price, R J. 1983. ''Scotland’s environment during the last 30 000 years'' (Edinburgh: Scottish Academic Press.)</ref> recorded the shoreline elevation of periglacial Lake Blane, west of Balfron. Smith et al. (1978)<ref name="Smith 1978">Smith, D E, Thompson, K S R, and Kemp, D D. 1978. The Late Devensian and Flandrian history of the Teith Valley. ''Boreas'', Vol. 7, 97–107.</ref> related deglaciation features in the Teith valley around and south-east of Callander to both the Dimlington Stadial ice sheet (27 000–13 500 years BP) and the later Loch Lomond Stadial glaciation. Merritt et al. (1990)<ref name="Merritt 1990">Merritt, J W, Coope, G R, Taylor, B J, and Walker, M J C. 1990. Late Devensian organic deposits beneath till in the Teith Valley, Perthshire. ''Scottish Journal of Geology'', Vol. 26, 15–24.</ref> described organic silts from the upper Teith valley, near Callander, which relate to both the Windermere Interstadial (13 500–11 000 years BP) and the Loch Lomond Stadial. Sissons and Smith (1965) presented evidence for rapid sea level rise in this area during the Flandrian Interstadial (<10 000 years BP). The formation names for glacial deposits present in the area are given in Browne and McMillan (1989)<ref name="Browne 1989">Browne, M A E, and Mcmillan, A A. 1989. Quaternary geology of the Clyde Valley. ''British Geological Survey Research Report'', SA/89/001.</ref>.

==References==
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== Geology of the Aberfoyle district - contents ==
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