Book Reviews

Abstract

Naturally occurring plant and animal pigments have long aroused intense scientific interest. The vivid red organic pigments, the petroporphyrins, present as minor components of many sediments and petroleums, are now receiving increasing attention in the field of organic geochemistry. First observed 50 years ago, and thought to arise in part from the green photosynthetic pigment chlorophyll in ancient organisms, they provided the first firm evidence for a biogenic origin for petroleum. Recent improvements in microanalytical chemical techniques have shown that the petro porphyrins are generally complex mixtures of a variety of closely related structural types. The distributions of the components as revealed by direct insertion probe mass spectrometry (MS), high-performance liquid chromatography (HPLC) and computerised gas chromatography-mass spectrometry (CGCMS) can provide a record of the original depositional palaeoenvironment and subsequent thermal history of the sedimentary matrix. The petroporphyrins are finding increasing application as a maturity parameter in petroleum geochemistry, complementing information from other biological marker components, and, in conjunction with geological and geophysical measurements, they can help to enhance the efficiency of exploration programmes.