Finding Geological Heritage: Legal Issues on Private Property and Fieldwork. The Case of Outstanding Early Angiosperms (Barremian to Albian, Portugal)

摘要

The Lower Cretaceous (Barremian to lower Albian) of Central Portugal yields some of the earliest and best-preserved angiosperms, which are excellent materials to study the mid-Cretaceous fast and huge diversification of angiosperms. Regional stratigraphic and sedimentological studies are crucial to enlighten the timing and environmental forcing factors of angiosperm evolution, namely geodynamics, magmatism, climate and oceanography. During a research project focusing upon these questions, access to an exploitation of mineral resources (a sand mine) was denied, leading to the present debate. National and international declarations and legislation increasingly commit states to consider geoheritage identification, protection and conservation as public interest. As scientific research is the first step within this process, access of researchers to a studied area should be the rule, regardless of legal tenure, with exceptions related to security matters or proprietary data. Both Portuguese laws governing mineral resources and geoheritage recognise many geological materials (mineral resources, sites, outcrops, fossils etc.) as vulnerable and non-renewable, requiring precautionary and conservative management based in scientific knowledge, but only the mineral resources laws foresees restrictions to private property rights for geological fieldwork. To balance the private rights and the public interest, we propose that the law should concede access to private property for officially recognised researchers and/or researchers of officially recognised projects. For activities acquiring geological data, creating exposures or mineral extraction, concession contracts should include clauses to allow access to such researchers and, for major operations, the obligation to notify interesting geological finds. We believe that geoconservation and the sustainable use of mineral resources cannot be jeopardised by access restrictions to scientific fieldwork.