Torbanite, also known historically as boghead coal or kerosene shale, is a variety of fine-grained black

oil shale Oil shale is an organic-rich Granularity, fine-grained sedimentary rock containing kerogen (a solid mixture of Organic compound, organic chemical compounds) from which liquid hydrocarbons can be produced. In addition to kerogen, general compos ...

. It usually occurs as lenticular masses, often associated with deposits of Permian

coal Coal is a combustible black or brownish-black sedimentary rock, formed as rock strata called coal seams. Coal is mostly carbon with variable amounts of other Chemical element, elements, chiefly hydrogen, sulfur, oxygen, and nitrogen. Coal i ...

s. Torbanite is classified as

lacustrine A lake is often a naturally occurring, relatively large and fixed body of water on or near the Earth's surface. It is localized in a basin or interconnected basins surrounded by dry land. Lakes lie completely on land and are separate from t ...

type oil shale. A similar mineral,

cannel coal Cannel coal or candle coal is a type of bituminous coal, also classified as terrestrial type oil shale. Hutton(1987) Dyni (2006), pp. 3–4 Speight (2012), pp. 6–7 Due to its physical morphology and low mineral content cannel coal is considered ...

, is classified as being a terrestrial form of oil shale, not a lacustrine type. Torbanite is named after Torbane Hill near

Bathgate Bathgate ( or , ) is a town in West Lothian, Scotland, west of Livingston, Scotland, Livingston and adjacent to the M8 motorway (Scotland), M8 motorway. Nearby towns are Linlithgow, Livingston, and West Calder. A number of villages fall under ...

West Lothian West Lothian (; ) is one of the 32 council areas of Scotland, bordering (in a clockwise direction) the City of Edinburgh council area, Scottish Borders, South Lanarkshire, North Lanarkshire and Falkirk (council area), Falkirk. The modern counci ...

, Scotland, a major location of occurrence. Torbanite found in Bathgate may have formations of

bathvillite Bathvillite is a naturally occurring organic substance. It is an amorphous, opaque, and very friable material of fawn-brown color, filling cavities in the torbanite or Boghead coal of Bathville, Lothian, Scotland. It has a specific gravity of 1.0 ...

found within it. Historically, two other names have been used for torbanite. Boghead coal is named after Boghead estate, also near Bathgate in Scotland. In Australia, the historical name for torbanite was kerosene shale. Other major deposits of torbanite are found in

Pennsylvania Pennsylvania, officially the Commonwealth of Pennsylvania, is a U.S. state, state spanning the Mid-Atlantic (United States), Mid-Atlantic, Northeastern United States, Northeastern, Appalachian, and Great Lakes region, Great Lakes regions o ...

and

Illinois Illinois ( ) is a U.S. state, state in the Midwestern United States, Midwestern United States. It borders on Lake Michigan to its northeast, the Mississippi River to its west, and the Wabash River, Wabash and Ohio River, Ohio rivers to its ...

, US, in

Mpumalanga Province Mpumalanga () is one of the nine provinces of South Africa. The name means "East", or literally "The Place Where the Sun Rises" in the Nguni languages. Mpumalanga lies in eastern South Africa, bordering Eswatini and Mozambique. It shares bor ...

in South Africa, in the

Sydney Basin The Sydney Basin is an Interim Biogeographic Regionalisation for Australia, interim Australian bioregion and is both a structural entity and a depositional area, now preserved on the east coast of New South Wales, Australia and with some of its ...

New South Wales New South Wales (commonly abbreviated as NSW) is a States and territories of Australia, state on the Eastern states of Australia, east coast of :Australia. It borders Queensland to the north, Victoria (state), Victoria to the south, and South ...

, Australia, the largest deposit of which is located at Glen Davis, and in

Nova Scotia Nova Scotia is a Provinces and territories of Canada, province of Canada, located on its east coast. It is one of the three Maritime Canada, Maritime provinces and Population of Canada by province and territory, most populous province in Atlan ...

, Canada. Organic matter (

telalginite Telalginite is a structured organic matter (alginite) in sapropel, composed of large discretely occurring colonial or thick-walled Microorganism, unicellular algae such as ''Botryococcus'', ''Tasmanites'' and ''Gloeocapsomorpha prisca''. Telalginite ...

) in torbanite is derived from

lipid Lipids are a broad group of organic compounds which include fats, waxes, sterols, fat-soluble vitamins (such as vitamins A, D, E and K), monoglycerides, diglycerides, phospholipids, and others. The functions of lipids include storing ...

-rich microscopic plant remains similar in appearance to the fresh-water colonial

green alga The green algae (: green alga) are a group of chlorophyll-containing autotrophic eukaryotes consisting of the phylum Prasinodermophyta and its unnamed sister group that contains the Chlorophyta and Charophyta/ Streptophyta. The land plants ( ...

Botryococcus braunii ''Botryococcus braunii'' is a green, pyramid-shaped planktonic microalga that is of potentially great importance in the field of biotechnology. Until 2024 it was considered to have three races: A, B, and L., but it was then determined that these ...

''. This evidence and extracellular

hydrocarbon In organic chemistry, a hydrocarbon is an organic compound consisting entirely of hydrogen and carbon. Hydrocarbons are examples of group 14 hydrides. Hydrocarbons are generally colourless and Hydrophobe, hydrophobic; their odor is usually fain ...

s produced by the alga have led scientists to examine the alga as a source of

Permian The Permian ( ) is a geologic period and System (stratigraphy), stratigraphic system which spans 47 million years, from the end of the Carboniferous Period million years ago (Mya), to the beginning of the Triassic Period 251.902 Mya. It is the s ...

torbanites and a possible producer of

biofuel Biofuel is a fuel that is produced over a short time span from Biomass (energy), biomass, rather than by the very slow natural processes involved in the formation of fossil fuels such as oil. Biofuel can be produced from plants or from agricu ...

s. Torbanite consists of subordinate amounts of

vitrinite Vitrinite is one of the primary components of coals and most sedimentary kerogens. Vitrinite is a type of maceral, where "macerals" are organic components of coal analogous to the "minerals" of rocks. Vitrinite has a shiny appearance resembling g ...

and

inertinite Inertinites are a group of partially oxidized organic (mainly plant) materials or fossilized charcoals, all sharing the characteristic that they typically are inert (i.e., not altered) when heated in the absence of oxygen. Inertinite is a common m ...

; however, their occurrence varies depending on deposits. A rubber-like, elastic, highly-resilient bituminous substance, known as coorongite—classified as an organic-rich sediment and named after the Coorong where it was found—has been identified as a 'peat stage' in the formation of torbanite. It provides evidence of the lacustrine and algal origin of torbanite. Substances very similar to coorongite had other historical names, depending upon the location of the deposits, such as n'hangellite from Portuguese East African (now

Mozambique Mozambique, officially the Republic of Mozambique, is a country located in Southeast Africa bordered by the Indian Ocean to the east, Tanzania to the north, Malawi and Zambia to the northwest, Zimbabwe to the west, and Eswatini and South Afr ...

) and marahunite from

Brazil Brazil, officially the Federative Republic of Brazil, is the largest country in South America. It is the world's List of countries and dependencies by area, fifth-largest country by area and the List of countries and dependencies by population ...

. Torbanite typically comprises 88%

carbon Carbon () is a chemical element; it has chemical symbol, symbol C and atomic number 6. It is nonmetallic and tetravalence, tetravalent—meaning that its atoms are able to form up to four covalent bonds due to its valence shell exhibiting 4 ...

and 11%

hydrogen Hydrogen is a chemical element; it has chemical symbol, symbol H and atomic number 1. It is the lightest and abundance of the chemical elements, most abundant chemical element in the universe, constituting about 75% of all baryon, normal matter ...

. Paraffin oil can be distilled from some forms of torbanite, a process discovered and

patent A patent is a type of intellectual property that gives its owner the legal right to exclude others from making, using, or selling an invention for a limited period of time in exchange for publishing an sufficiency of disclosure, enabling discl ...

ed by James Young in 1851.

References

{{Reflist Coal Oil shale geology

See also

References