coal

8 subentries

• coal (59:5sec)
• beds often hold gas and oil (59:5.16)
• deposition (60:2.7) (60:3.9) (61:2.3)
• between glacial layers (59:6.6)
• Carboniferous was era of (59:5sec)
• laid down 200 million years ago (59:5.13)
• layers alternate with shale, stone, and conglomerate (59:5.15)
• some coal-bearing strata are 18,000 feet thick (59:5.15)
• water-preserved, pressure-modified remains of rank swamp vegetation (59:5.14-17)

Cited alongside

Headwords that cite the same paragraphs as this one, commonest first. The number is how many subentries each has.

• Europe 18
• glaciers 5
• oil (petroleum) 2
• shale 5