Coal Lithotype Composition Matching Explained

This question requires matching different types of coal lithotypes (LIST-I) with their primary compositional characteristics (LIST-II). Understanding the maceral composition is key to identifying these coal types.

Coal Lithotypes and Compositions Overview

Detailed Match Explanations

Vitrain Maceral Composition Explained

Vitrain is a bright, lustrous coal layer. Its primary component is the vitrinite maceral group. Typically, Vitrain contains predominantly vitrinite, with less than 20% of other macerals like liptinite (exinite) or inertinite. This aligns with the description: III. Vitrinite macerals with $< 20\%$ exinite macerals.

Cannel Coal Origin and Composition

Cannel coal is a unique type of coal known for its fine texture, high hydrogen content, and dull luster. It is formed mainly from the remains of algae and spores, meaning it is characteristically rich in liptinite macerals, particularly alginite. Therefore, Cannel coal matches with: IV. Dominated by alginite.

Durain Lithotype Characteristics

Durain is a dull, hard, and often gritty coal. It is recognized for its heterogeneous mixture of macerals. Durain typically contains significant proportions of both the inertinite group (such as fusinite and semi-fusinite) and the exinite (liptinite) group. This corresponds to the description: I. Mainly inertinite and exinite macerals.

Fusain Structure and Components

Fusain, also known as mineral charcoal, is a fragile, powdery coal layer often found as lenses within other coal seams. It originates from fossilized charcoal resulting from plant tissues subjected to heat or fire. The dominant maceral group in Fusain is fusinite, which is a type of inertinite. Thus, Fusain matches with: II. Mainly fusinite.

Summary of Correct Matches

Based on the detailed analysis of each coal lithotype's composition:

• A. Vitrain matches with III. Vitrinite macerals with $< 20\%$ exinite macerals.
• B. Cannel coal matches with IV. Dominated by alginite.
• C. Durain matches with I. Mainly inertinite and exinite macerals.
• D. Fusain matches with II. Mainly fusinite.

The correct combination is A-III, B-IV, C-I, D-II.