Title: Comparison of nickel and vanadyl porphyrin distributions of sediments
Abstract: The distributions of nickel and vanadyl porphyrins of Toarcian shale, northern Germany, and the Monterey Formation, California, were examined. The compositions of nickel and vanadyl porphyrin fractions of extracts from the same sample show substantial differences. The nickel porphyrin distribution is more complex than the vanadyl porphyrin distribution. While the vanadyl porphyrin distributions of samples from a core are the same, their nickel porphyrin compositions show wide variations. The nickel porphyrins are enriched in "etio" and 3-nor C30DPEP structures. The vanadyl porphyrins are enriched in the C33DiDPEP structure. Methylpropano porphyrins are found only in the vanadyl porphyrin fraction, whereas the cycloheptano structural type is predominant in the nickel fraction. C31DPEP and C32DPEP are found both in the nickel and vanadyl fractions. Their relative abundance in the two fractions is proportional to the NiVO porphyrin ratio. The observed differences in the compositions of nickel and vanadyl porphyrin fractions are due to differences in the rate constants for their formation from the pheopigments.
Publication Year: 1993
Publication Date: 1993-03-01
Language: en
Type: article
Indexed In: ['crossref']
Access and Citation
Cited By Count: 27
AI Researcher Chatbot
Get quick answers to your questions about the article from our AI researcher chatbot