Introduction

All applications involving benthic foraminifera must include an understanding of their ecology. The reason for this is that benthic foraminifera are closely linked to their environment of life. Even subtle changes in environmental parameters are matched by faunal change. That is why most of the book is devoted to an ecological synthesis because that provides the modern database with which fossil assemblages may be compared. The aim of this chapter is to describe the rationale and methods used in the various applications and to give case studies as appropriate but no attempt is made to provide a synthesis of all available results. There are five broad groups of applications with considerable overlap between them.

• Sequence stratigraphy – biostratigraphy.

• Interpretation of past environments, such as marsh, brackish lagoon, etc. in the geological record (palaeoecology).

• Interpretation of specific details of environments or processes such as palaeoproductivity, low oxygen, seasonal stratification of the water column, etc. (palaeoceanography).

• A proxy for natural environmental change (e.g., sea level, climate).

• Monitoring of changes induced by the activities of man.

In its broadest sense, palaeoecology might be considered to include palaeoceanography and environmental change but I have chosen to treat them separately as they have become important fields in their own right. Before considering these applications it is appropriate to comment on the use of the modern database as a reference for interpreting the fossil record.

The present as a key to the past

Interpretations of the fossil record depend largely on comparison with modern ecology (or geochemistry for chemical techniques).