Do you know how the coal form?

You will often find imprints of leaves, flowers and other plant parts in coal. Also, peat under sufficient temperature and pressure, will eventually turn into lignite, and under the same conditions, will eventually turn to coal.

Thank you for your explain, now there are two photo

see arrow, they are clip lay in coal. they seem plant residue.

why they reserved and cannt change into coal?

they layers like shale rock. are the shale also formed by plant?

you can find these clip layer plant easily.

Could be a layer of silt due to heavy rains flooding muddy rain water over the dead vegetation.

They could be due to mineralization as the plants were slowly turning into coal, or they could be due to mineral deposits left after water seeped into cracks in the coal .

Hello cnpower

Coal can be formed within a few weeks, if conditions of airlessness/pressure/temperature are ideal.

Often some plant or animal remains are found not decomposed.

That would be because of the nature of natural coal production, where there is no air present, there is high pressure gas present from the coal being formed, and decomposition cannot thus commence, because bacteria cannot survive to decompose the remains fully.

This type of "recent coal formation" is normally found in geologically very young strata, such as we often locate in some mines in New Zealand.

Kind Regards....

It is fairly certain that coal forms from pressure generated by the overburden of tons of soil on pre-historical forests. Petrographic analysis of coals have shown specific types of leaves and plant forms in the coals from different geological eras. In fact, the science has been carried out to define the types of byproducts formed by vitrinites, exinoids and fusinoidal types during carbonization. Suggest you look into Coal Petrographic Science in Lowry's Chemistry of Coal Utilization. I dont know whether Wikipedia or the Internet search engines have anything on this subject. It is well developed.

Outstanding answer!

Hello RHABE

A good answer thanks, you got my vote.

Kind Regards....

Hi RHABE.

I live in the Black Country in central England, here there has been coal mining from 1300 onwards. We have a very rare occurence of so-called thick coal, this seam was 30ft thick and produced by a whole forest of ferns being swept aside by a huge landside into a narrow but deep valley. Geologists have calculated that this huge pile of ferns must have been at least 600ft thick to produce this thick seam coal, on top of this lies a thick layer of carbon bearing clay, marle, mudstone, and boulder clay.

We have in the local museum a huge number of fossil plants, whole tree fern stems and fossilised fish teeth, it was this abundence of coal that gave rise to the Industrial Revolution in the 18th century. The iron ore was extracted from the marle and mudstone strata as calcerous iron nodules which can still be found today.

The whole area is also home to fossols from the silurian deposits, 600 of the fossils are type locallity fossils. There are 726 coal mines, now defunct and the man made limestone caverns where the limestone was extracted for iron smelting are among the the largest man made underground caverns in the world.

I will try to post some photo's of all this.

Spencer.

Hi Spencer,

Were you refering to the Limestone mines in Dudley ? I just found out about this project. Looks like a good place to visit.

Hi Kris.

Sorry about the late reply, I have only just arrived home. Yes that is what I was refering to, Wrens Nest cavernes and Dudley hill. I have been down into these huge caverns many times. A canal that starts one mile away runs under through these hills straight into the caverns, the miners loaded the narrow boats with limestone in the caverns, and transported it to the blast furnesses.

Yes you should come and visit this place sometime in the future, I live two miles from these caverns, you will be very surprised.

Spencer.

"a very rare occurrence of so-called thick coal, this seam was 30ft thick"

Hi Scapolie,

thank you for this information, interesting. If this really was a landslide then there must be a lot of soil derived non-coal inclusions, and there must be a more or less total disorder of depositions: no stratifications, no fossils bigger than a few cm.

May be the fern forests have grown on the shallow shorelines of this deep valley and the deposits slowly or suddenly migrated downhill after some thickness accumulated.

This would have to be a continuous or periodic process may be for many many years.

I do not believe in 600yards swept in only in one big surge. ?

Any details known?

Thanks

RHABE

Hi RHABE.

Google; Dudleys thick seam coal, and Dudley coal mines, I think that you will be surprised!

Spencer.

Here's one link to the Dudley seam(s). Because of it's organic origins, coal is one of the most variable types of rock. Many seams such as the Dudley one are actually several seams, but with a narrow separation. Usually the margins of a seam are well defined, but nature can conspire to do otherwise. A ranging drum shearer is designed specifically so the operator can follow the undulations of a seam (within design limits). Water erosion after plant matter is layed down can leave huge 'barren' channels. The ultimate nightmare in coal mining (apart from loss of life) is discovering a 'washout'. No coal = no money, plus the shearer is not optimized for sandstone (or whatever). Boreholes can only reveal so much in advance of mining. The 'Retreat' method of longwall mining involves driving two parallel roadways first (the ends are then connected and a face set up. It's no small feat installing shearer,conveyors and supports. Initiating caving behind the supports can also be problematic. The overlying rock must collapse in a controlled manner into the mined-out area, to control weight on the supports). This enable some degree of pre-proving reserves, but takes longer to access the goodies. 'Advance' longwall mining gets you there quicker, but is hellish annoying if a face is set up and then runs out of coal. Support and ventilation also play a large part in planning decisions.

Hi Kris.

I do remember that TV program last week, I just did not know it was called the deep trench. I live within walking distance of the Baggerage deep pit coal mine, now Baggerage has a huge open pit there mining for the huge amounts of brick clay. They also make the bricks in situ at this site.

I was brought up in Halesowen within spitting distance of the so-called Hawn colliery, and in 1952 the colliery closed and they started to dig the clay out of there too. This lasted until 1964 when the clay ran out, it was mined by Doulton and called the doulton brick works. Both the coal and the bricks were transported by narrow boat to Stourbridge canal junction where they were then transfered to the rail network.

By 1854 there were 279 collieries within the Dudley-Halesowen area alone, and the last coal to be brought out was in 1964. In those days the Black Country area was known as the workshop of the whole world, and in many places locally much of the old workshops and a colliery exist to this day as a living monument to the past industries.

Spencer.

A lot depends on the age and how much pressure the coal has been under. Peat is not quite coal, but given time would form a soft brown coal. Over time, as the coal is buried and compressed, it compacts and becomes very hard. The hardest has even been used as jewelry. Anthracite is a hard coal which does not show its plant origins, but softer coals show leaf patterns, wood patterns and such, which confirms that coal did come from plants. This is not a theory which you can choose to disbelieve simply because you find some coal that doesn't seem to fit, it is an established fact. Ancient swampy forests built up layers of decaying plant material hundreds of feet thick, then they were covered with mud which became stone as more layers formed on top of it. The old forest was gradually compressed into coal. It took millions of years.

I vote 13# and 19# and others.

but you should explain, why some plants still clip in the layers? and hvnt yet turn into coal?

that really doesn't tell you nothing. but next time look on the internet and find some more information thank you 4 the time