Karelian shungite—an indication of 2.0-Ga-old metamorphosed oil-shale and generation of petroleum: geology, lithology and geochemistry

Mineral-templated growth of natural graphite films

“…The Paleoproterozoic Zaonega succession of siliciclastic, carbonate and sedimentary rocks, and mafic tuff, interlayered and intersected by mafic lavas and sills (Galdobina, 1987), is exceptionally rich in organic carbon (Fillipov, 1994), and represents one of the earliest geological manifestations of significant petroleum generation in Earth history (Melezhik et al, 2009;Melezhik et al, 1999). These organic-rich rocks have often been referred to as shungite (after Shunga village in Karelia), which in the literature appears as a general term for organic carbonrich rocks from the Paleoproterozoic Onega Basin (Buseck et al, 1997;Fillipov, 1994;Kovalevski et al, 2001), although many authors (Kovalevski, 1994;Melezhik et al, 1999) describe shungite as a type of CM found in these rocks following the original terminology of Inostranzev (1879).…”

“…These organic-rich rocks have often been referred to as shungite (after Shunga village in Karelia), which in the literature appears as a general term for organic carbonrich rocks from the Paleoproterozoic Onega Basin (Buseck et al, 1997;Fillipov, 1994;Kovalevski et al, 2001), although many authors (Kovalevski, 1994;Melezhik et al, 1999) describe shungite as a type of CM found in these rocks following the original terminology of Inostranzev (1879). The minimum age of ca.…”

“…Several intervals are pervasively impregnated with pyrobitumen that results in obliteration of sedimentary layering, and in places massive appearance of the host sedimentary rock (Fig.2). Numerous veins consisting largely of pyrobitumen or containing also quartz and carbonate can be observed throughout the Zaonega Formation as well as in overlying sedimentary and volcanic rocks (Melezhik et al, 2009;Melezhik et al, 1999). Pyrobitumen-rich intervals that are in places rich in silicates (Melezhik et al, 2004), are found in the contact zones of magmatic bodies, but also occur as layers within sedimentary successions.…”

“…Pyrobitumen-rich intervals that are in places rich in silicates (Melezhik et al, 2004), are found in the contact zones of magmatic bodies, but also occur as layers within sedimentary successions. CM in the Zaonega Formation display a large overall range in δ 13 C org (-45 to -17 ‰) and a low average H/C-ratio (0.005-0.2), indicating various precursor materials and 6 a complex history of oil generation, migration, and subsequent thermal alteration (Buseck et al, 1997;Fillipov, 1994;Khavari-Khorasani, 1979;Melezhik et al, 1999). The association of pyrobitumen with mafic lava flows and co-magmatic sills is consistent with a contact-heatinduced hydrocarbon generation and migration (Rankama, 1948), coeval and/or shortly postdating the sedimentation.…”

Terrestrial and Extraterrestrial Fullerenes

“…At Shunga and Sudbury there are no fossil remains in the fullerene-bearing rocks. [176] In the case of Shunga the opinions on an algal parentage of the carbonaceous matter are divided [108,177] . For Sudbury, the biologic origin of the carbon in the BMOF was firmly proven.…”