Classification of huminite—ICCP System 1994

doi:10.1016/j.coal.2004.06.006

International Journal of Coal Geology

Volume 62, Issues 1–2, 12 April 2005, Pages 85-106

https://doi.org/10.1016/j.coal.2004.06.006 Get rights and content

Abstract

In the new classification (ICCP System 1994), the maceral group huminite has been revised from the previous classification (ICCP, 1971. Int. Handbook Coal Petr., suppl. to 2nd ed.) to accommodate the nomenclature to changes in the other maceral groups, especially the changes in the vitrinite classification (ICCP, 1998. The new vitrinite classification (ICCP System 1994). Fuel 77, 349–358.). The vitrinite and huminite systems have been correlated so that down to the level of sub-maceral groups, the two systems can be used in parallel. At the level of macerals and for finer classifications, the analyst now has, according to the nature of the coal and the purpose of the analysis, a choice of using either of the two classification systems for huminite and vitrinite. This is in accordance with the new ISO Coal Classification that covers low rank coals as well and allows for the simultaneous use of the huminite and vitrinite nomenclature for low rank coals.

Introduction

The International Committee for Coal and Organic Petrology (ICCP) is continuously revising ICCP's classification systems for macerals. A new vitrinite classification system was published in 1998 (Fuel 77, 349–358, ICCP, 1998), and in 2001, the new inertinite classification system was published (Fuel 80, 459–471, ICCP, 2001). These systems are collectively referred to as the “ICCP System 1994”. They are the result of the work of two editorial groups combined with extensive discussions and revisions of prepared drafts during several annual ICCP meetings attended by numerous international experts.

This document presents the ICCP huminite classification and is also a part of the “ICCP System 1994”. The definitions of the huminite macerals have been presented, discussed and approved at annual ICCP meetings.

Section snippets

Origin of term

Term introduced by Szádecky-Kardoss (1949) for a structural constituent of brown coals (now commonly termed lignites). The ICCP has used this term for a maceral group of lignites (brown coals) since 1970. Derivation: humus (L)–soil.

Related terms

Vitrinite (low, medium and high rank coals; ICCP, 1998).
Gelinite (Babinkova and Moussial, 1965, Belau et al., 1967).

Definition

Huminite designates a group of medium grey macerals having reflectances generally between those of the associated darker liptinites and the lighter

Origin of term

Term introduced by the ICCP 1970 to denote huminite with cell structure. This structure is visible to variable extent in reflected white light. Derivation: humus (L)–soil, tela (L)–tissue.

Related terms

Humoses Pflanzengewebe (Teichmüller, 1950)
Humophyt (Svoboda, 1956)
Xylinit (Szádecky-Kardoss, 1949, Waltz, 1956)
Xylinit-Gruppe (Jacob, 1961)
Textinit (Sontag et al., 1965)
Telovitrinit (Jacob, 1970)
Humotelinite (ICCP, 1971)

Definition

Telohuminite is a subgroup of the maceral group huminite comprising macerals with preserved

Origin of term

Term proposed to the ICCP in 1963 to describe huminitic cell wall material in lignites (brown coals). In the same sense used by Sontag et al. (1965). In 1970 the ICCP restricted the term to a maceral consisting of ungelified cell wall material. Derivation: textum (L)–tissue.

Related terms

Textinit, nicht vergelt (Sontag et al., 1965)
Pflanzengewebe (Teichmüller, 1950)
Xylinite and Phyllinite (Svoboda and Beneš, 1955)
Xylinite (Szádecky-Kardoss, 1949, Jacob, 1961, Minčev, 1962)
Gelinito-Telinit (Timofeev et al.,

Origin of term

Term used at first by Stopes (1935) for “completely gelified plant material” in coals. In 1970 introduced by the ICCP to denote more or less gelified plant tissues in which cell structures still can be seen. Derivation: ulmus (L)—elm; ulmin is a decomposition product of diseased elms (Vauquellin, 1797).

Related terms

Textinit, halb vergelt;Textinit, vergelt (Sontag et al., 1965)
Xylovitrinit, Vitrinit (Minčev, 1964)
Gelinito-Telinit, Gelinito-Posttelinit (Timofeev et al., 1962)
Xylovitrain, Strukturvitrain (

Origin of term

Term introduced by the ICCP in 1970 to denote a subgroup of huminite. Derivation: humus (L)–soil; detritus (L)–a product of disintegration.

Related terms

Transmitted light microscopy: Translucent humic degradation matter (Thiessen, 1930)

Reflected light microscopy	Detrinit-Gruppe (Jacob, 1961)
	Detrinit (Malán, 1965, Sontag et al., 1965, Svoboda, 1956)
	Attrite and desmite (Waltz, 1960)
	Attrinite (Minčev, 1964)
	Desminite (Minčev, 1964), in part
	Humodetrinite (ICCP, 1971)
	Detrohuminite (Kalkreuth et al., 1991), in part

Definition

Origin of term

Term suggested by Babinkova and Moussial (1965) following a proposal of the Association of Coal Petrographers of the USSR in 1963. Originally, the term denoted gelified particles in lignites. The ICCP has used the term since 1970 for a maceral of the huminite group that consists of fine humic particles that form the non-gelified “groundmass“of (brown) coals. Derivation: attritus (L)–matter pulverized by attrition.

Related terms

Detritus (Wiesner, 1892)
Unvergelter Detrinit (Sontag et al., 1965)
Humoser Detritus

Origin of term

Term introduced by the ICCP in 1970 to denote a maceral of the huminite group that consists of gelified small particles cemented by amorphous humic matter. Derivation: densus (L)–dense, compact.

Related terms

Transmitted light:	Translucent humic degradation matter (Thiessen, 1930)
Reflected light:	Vergelter Detrinit (Sontag et al., 1965)
	Detrinit (Svoboda and Beneš, 1955, Jacob, 1961), in part.
	Detritus (Wiesner, 1892)
	Humoser Detritus (Teichmüller, 1950)
	Gelinito-Posttelinit, Gelinito-Praecollinit (Timofeev and

Origin of term

Term introduced by the ICCP to denote a maceral subgroup comprising macerals originating from amorphous humic matter. Derivation: gelu, us (L)–frost, stiffening humus (L)–soil.

Related terms

Gel (Schochardt, 1943, Teichmüller, 1952)
Gelinit (Malán, 1965, Podgajni, 1957, Sontag et al., 1965)
Dopplerinit-Gruppe (Jacob, 1964)
Humocollinite (ICCP, 1971)

Definition

Gelohuminte denotes a maceral subgroup within the maceral group huminite that comprises grey coloured structureless, homogenous substances of huminite reflectance.

Origin of term

Term introduced by the ICCP in 1970 for a maceral of the huminite group that consists of structureless bodies of humic cell fillings. Derivation: corpus (L)–body; humus (L)–soil.

Related terms

Melanoresinit (Szádecky-Kardoss, 1946)
Phlobaphinit (Szádecky-Kardoss, 1949)
Corpogelinit (Teichmüller, 1950)

Definition

Corpohuminite is a maceral of the maceral group huminite, subgroup gelohuminite, consisting of homogenous, discrete bodies of former humic cell fillings occurring in situ together with textinite or ulminite or

Origin of term

Term introduced by Szádecky-Kardoss (1949) for precipitated humic gels and adopted by the ICCP to denote a maceral of the huminite group consisting of formless huminitic gels. Derivation: gelu, us (L)—frost, stiffening.

Related terms

Gel(e) (Schochardt, 1940, Schochardt, 1943, Teichmüller, 1950)
Humusgel (Berger, 1958, Hummel, 1930)
Dopplerinit (Jacob, 1961)
Huminit (Svoboda, 1956)
Desminit (Minčev, 1964)
Gelinito-Collinit (Timofeev and Bogoliubova, 1965)

Definition

Gelinite is a maceral of the maceral group huminite

Acknowledgements

The authors wish to thank all members of ICCP, who helped with critical discussions and reviews during the process of writing and the final ICCP approval of the text. Thanks also go to Gerd Bieg at Ruhranalytik (now DSK) lab in Herne for the use of the photographic equipment and support. One of the authors (WP) especially wishes to thank Heather Middleton at CSIRO Petroleum and Petra David at TNO for help with the last missing references.

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