We mainly use biomarkers for the study of palaeoenvironmental evolution of different areas of the Iberian Peninsula. Biological marker molecules (biomarkers) comprise chemical records of organisms in the ancient environment: they are organic compounds linked to a specific biotic sources which retain their source of information after burial in sediments, even after some alteration. Biomarkers in geologically old sediments and rocks are usually stabilized derivatives of their precursor compounds. They comprise families of organic compounds like hydrocarbons, ketones, fatty acids, hopanes or steranes, although monospecific compounds such as dehydroabietic acid botryococcane or gammacerane, among others, are also consider as biomarkers of specific plants.
They are usually extracted using organic solvents as dichloromethane or methanol and analysed using a gas-chromatograph with a selective masss-detector (GC/MS).
