Thermal Maturity of Early Paleozoic Sediments as Determined By the Optical Properties of Marine-Derived Organic Matter — A Review

Thermal history and source rock characterization of a Paleozoic section in the Awbari Trough, Murzuq Basin, SW Libya

“…(3) degradation products of algae (Glikson and Taylor, 1986;Goodarzi et al, 1992). We have used the term vitrinite-like particles as its origin is not clear, but we compared it with those in the Alum shale and Tarim Basin in China and found that they have many similarities in terms of shape.…”

Graptolites as fossil geo-thermometers and source material of hydrocarbons: An overview of four decades of progress

“…Vitrinite reflectance is a most commonly used indicator for the thermal maturity (Stach et al, 1982;Taylor et al, 1998;Suárez-Ruiz et al, 2012;Hackley and Cardott, 2016). However, due to the lack of vitrinite (coalified wood) in pre-Devonian rocks, the determination of thermal maturity of Lower Paleozoic graptolite-bearing rocks is always a difficult topic and a hot debate for petroleum industry (Goodarzi, 1984;Goodarzi, 1985a;Norford, 1985, 1987;Bertrand and Heroux, 1987;Bustin et al, 1989;Bertrand, 1990;Goodarzi et al, 1992a;Bertrand, 1993;Petersen et al, 2013;Luo et al, 2016;Luo et al, 2017;Luo et al, 2018). Thus, the surrogate proxies, such as the reflectance of zooclasts, vitrinite-like particles and solid bitumen, T max , and biomarkers, have been proposed to assess organic maturity in Lower Paleozoic graptolite-bearing sediments (Teichmüller, 1978;Goodarzi and Norford, 1987;Jacob, 1989;Schoenherr et al, 2007;Suárez-Ruiz et al, 2012;Schmidt et al, 2019).…”

Organic Petrology of Potential Source Rocks in the Tarim Basin, Nw China

“…However, Lower Palaeozoic source rocks are marine and vitrinite is not present in pre-Silurian rocks due to the absence of vascular plants. Consequently, the reflectances of protobitumen, zooclasts (graptolites, chitinozoans and conodonts) and vitrinite-like macerals were used as maturity indices following previous publications (Jacob, 1989;Riediger, 1993;Norford, 1985, 1989;Goodarzi et al, 1992;Bertrand and Heroux, 1987;and Buchardt and Lewan, 1990). Bitumen reflectance was converted into equivalent vitrinite reflectance using the formula VR=0.618Rb+0.4 published by Jacob (1989).…”