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Contents

Introduction
What are alluvial plains?
Where alluvial plains are found
The plains as a natural resource
A complex system affected by environmental changes
How to gain knowledge about the plains
Geological maps
The formation of alluvial plains
Empordà plain
The lower Rhine alluvial plain
The Little Hungarian plain
The Po plain
Conclusion

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Introduction

This booklet was prepared by four European national and regional geological surveys that are involved in the study of "alluvial plains".

Alluvial plains are a part of the uppermost part of the Earth's crust, and as such, supporters of life. This part of the lithosphere also holds all the currently accessible mineral resources. However, its capacity of production and storage is limited and, as its geological structure is very complex, it is very sensitive to the modifications caused by modern human development. Extraction activities, such as mineral or groundwater production, and storage in a broad sense, such as building, the altering of river courses or waste disposal sites, can result in profound changes in the properties of soils and subsurface sediment. History on a human scale shows how such changes can eventually lead to a definitive loss of extensive areas which were previously the sites of flourishing activities.

In the course of the following pages we explain what alluvial plains are, how they were formed, why people have always chosen them as their dwelling-place and why and how the alluvial plains are so much at risk of damage by human action.

This booklet is dedicated to all those people who are very attentive to knowledge about natural environment, its preservation and their geological heritage.

The geological surveys of the Netherlands, Hungary, Catalonia and Emilia-Romagna believe in the exchange of scientific knowledge and methodologies, and consider that the diffusion of acquired knowledge is of fundamental importance to any further development.

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