Weathered coal, as a humic acid resource formed by the weathering of lignite or low metamorphic bituminous coal, is highly concentrated in regions with abundant coal resources and a relatively long coal age worldwide. The core distribution is as follows:

1. Main distribution areas

China

North China region: Shanxi Province has reserves of approximately 8 billion tons (with high-quality mining areas such as Datong, Lingshi, and Wujiashan in Taiyuan having humic acid content exceeding 50%), and Inner Mongolia Autonomous Region has reserves of approximately 5 billion tons (represented by the Gongwusu mining area).

Northwest region: The Nanhu coalfield in Xinjiang has a reserve of 350 million tons, and Turpan and other areas are rich in humic acid.

Northeast region: The content of humic acid in weathered coal in Hegang and Qitaihe mining areas of Heilongjiang Province is high.

Central and Southwest China: Yuzhou in Henan Province (Gan County), Pingxiang in Jiangxi Province (with reserves exceeding 20 million tons and humic acid grades of 30-40% in the Mashan mining area), and also distributed in Luliang, Yunnan Province, Sichuan Province, and other areas.

Other key countries

Germany: The weathering zone of the Rhine lignite field is developed, and humic acid resources are abundant.

Australia: The weathering products of lignite in Victoria are widely used.

United States: North Dakota and Montana have significant reserves of weathered brown coal.

2. Distribution characteristics

Geological correlation: It is often associated with lignite and low metamorphic coal mining areas, such as the Carboniferous coal series in Shanxi, China and the Jurassic coalfield in Xinjiang.

Insufficient resource statistics: Global systematic surveys are insufficient, and a large amount of weathered coal has long been regarded as abandoned resources.

Quality difference: High quality weathered coal is concentrated in specific mining areas (such as Shanxi and Xinjiang in China), with humic acid content of over 50% and ash content below 20%.

Note: Currently, global data on weathered coal reserves is not yet complete, mainly due to the fact that it has not been counted as a mineral resource in the past, and future exploration potential is concentrated in lignite basins in Asia, North America, and Europe. 

Source:Deepseek