Skip to main navigation Skip to search Skip to main content

Biological markers in bitumens and pyrolyzates of Upper Cretaceous bituminous chalks from the Ghareb Formation (Israel)

  • Jürgen Rullkötter
  • , Zeev Aizenshtat
  • , Baruch Spiro

Research output: Contribution to journalArticlepeer-review

Abstract

The sterane and triterpane distributions of three bituminous chalks from the Upper Cretaceous Ghareb Formation (Israel) were investigated both in the original extractable bitumens and in extracts obtained after pyrolysis of whole rock and isolated kerogen samples at 450°C. Pyrolysis was performed in a closed system under hydrous (whole rock) and anhydrous conditions (isolated kerogens). The carbon number distributions of steranes and triterpanes differ significantly between original bitumen and pyrolyzates. Unlike the bitumens in which diasteranes were not detected, the anhydrous pyrolyzates contain small amounts of diasteranes. The presence of water during pyrolysis leads to an increase of sterane isomerization, the abundant formation of diasteranes and an increase of the 18α(H)-trisnorneohopane 17α(H)-trisnorhopane ratio. Sterane isomerization maturation parameters show a closer match between original bitumen and pyrolyzates after pyrolysis in a closed system when compared with an open system.

Original languageEnglish
Pages (from-to)151-157
Number of pages7
JournalGeochimica et Cosmochimica Acta
Volume48
Issue number1
DOIs
StatePublished - Jan 1984
Externally publishedYes

ASJC Scopus subject areas

  • Geochemistry and Petrology

Fingerprint

Dive into the research topics of 'Biological markers in bitumens and pyrolyzates of Upper Cretaceous bituminous chalks from the Ghareb Formation (Israel)'. Together they form a unique fingerprint.

Cite this