 The group underlies the Borrowdale Volcanic Group in the southern and central Lake District and the Eycott Volcanic Group in the northern part of the district.The Kirkland Formation has provided fossils of "Dichograptus octobrachiatus" and "Heminectere rushtoni".The sequence was affected by low-grade regional metamorphism and deformation associated with the Acadian Orogeny, causing the dominant fine-grained parts of the sequence to become slates.