SNH Guide to the Geology of East Lothian

Introduction

Volcanoes

Molten magma

The Borders volcanoes

Even older volcanoes

The Southern Uplands

Hutton's Unconformity

Deserts and dunes

Fossils

Ice

Seas, rivers and lochs

Geology

Rock

Building stones

A very good field guide is available to the varied and fascinating solid geology of East Lothian:

Lothian Geology: An Excursion Guide       ISBN 0-9044-4006-0.

Geology and scenery

East Lothian may be mainly lowland but it is far from flat. The coastal plain is punctuated by a set of eye-catching hills developed on hard volcanic rocks that recur as islands just offshore. The land is also corrugated, with long, gentle gradients on roads running east and steep ups and downs running south. Yet this local relief merely masks a stepped terrain rising to the dark rim of the Lammermuirs.

The cross section taken from the Third Statistical Account of the county shows three main elements:

  • a coastal plain developed across weak sandstone and limestone, with ridges of volcanic rocks
  • a set of topographic benches on the flanks of the Lammermuirs, incised by a magnificent system of deep meltwater channels
  • the Lammermuir escarpment and plateau which drops gently into the Tweed basin

The Lammermuir Fault along most of its length lets down weaker Old Red Sandstone against the tough grits, greywackes and metamorphosed shales of the Lammermuirs. In contrast, the Dunbar-Lammermuir Fault is rarely picked out in the terrain, as displacement has involved no juxtaposition of rocks of contrasting resistance. On the Old Red Sandstone the rich browns of the bare arable fields in winter remind us of counterpart hues in the stone and pantiles of old buildings in the coastal towns and villages. Everywhere from the coast to the hills the geological structure provides a skeleton for the land.