1961 russian log from teeg, page-36

Note from Russian log translation:
Above 14 M thick Jurassic coal seam:
"interbedded sandstones with siltstones and mudstones. Two unstable faunal horizon are found..."
and below 14M seam:
"medium sandstones interbedded with and guzernis grits and fine-grained calcareous sandstones in the cement"

This indicates lack of salts [old seas] and therefore low sulphur [?]

Regarding proximity to volcanic activity: too close and all the good stuff is incinerated further away yet close enough to 'cook' metallurgical and coking coal -
BTW notwithstanding drilling through basalt - the value of metallurgical coal could well justify that i am told by
COO of Glencore operation ...we will know a lot more in six-eight weeks ..so patience etc