Coal deposit thickness and how this could form over millions of years without contamination from slow sedimentation

[jpm (Phil McCurdy)]

While the white sand beaches of Pensacola and Gulf Shores are deposits of eroded quartz from the Appalachian Mountains.

[Jay313 (Jay Johnson)]

Never made it (yet) to the Redneck Riviera. Black sand beaches are more rare, but just as much a testament to erosion and the facts of geology.

[St.Roymond]

I remember my first visit to a black sands beach. My immediate thought was, “Awesome!”

Then I ran onto it barefoot.

[St.Roymond]

@jpm

While the white sand beaches of Pensacola and Gulf Shores are deposits of eroded quartz from the Appalachian Mountains.

Ive been an avid sand-castle builder all my life and was disappointed with Gulf beaches because the sand doesn’t serve as well for making castles.

[Paraleptopecten (Timothy Campbell)]

I took the legal approach to collecting some of the sand in spite of the “no collecting” rules: empty my shoes into vials.

[jpm (Phil McCurdy)]

That must be due to fine quartz crystals not interlocking like normal sand. And what gives it its squeak when you walk on it. Anyway, a good example of differential sedimentation from the eroded Appalachian mountains, also rich in coal deposits in an attempt to obliquely refer back to the original subject. And, as much of the coal is strip mined, that same erosion is what brought it close enough to the surface to be mined that way.

[St.Roymond]

@jpm

the eroded Appalachian mountains, also rich im coal deposits

The Appalachians are really old mountains; that they have coal deposits shows just how far back coal was formed. It also suggests that they were much more level.

[Jay313 (Jay Johnson)]

@St.Roymond

disappointed with Gulf beaches because the sand doesn’t serve as well for making castles.

You were on the wrong side of the Mississippi. Plus, in Texas we like to mix a bit of crude oil with the sand and then drive cars on the beach. You could build a cathedral!

Addendum: In defense of Texas beaches, Padre Island is probably the longest stretch of pristine, undeveloped beach in the US. It happened by historical accident, since all of it was once the property of the King Ranch.

[EastwoodDC (Dan Eastwood)]

@adamjedgar

… one of the thickest known coal seams is in Wyoming and is claimed to be in the order of 800 feet thick.

The claim is correct. I got a tour of Black Thunder Coal Mine (1996?) and saw it for myself.

There are sedimentary impurities in coal, typically ranging from trace amounts of silt to intermittent layers of sandstone or conglomerate.

This article looks interesting, but I’m on mobile and can’t view it myself just now.

GEOLOGIC DISTURBANCES IN ILLINOIS COAL SEAMS http://library.isgs.illinois.edu/Pubs/pdfs/circulars/c530.pdf

[rsewell (RON SEWELL)]

@EastwoodDC

This article looks interesting, but I’m on mobile and can’t view it myself just now.

The paper is a representative exhibit of how conventional geology is essential for efficient planning of resource extraction, and how useless the rhetoric of YEC is for any practical commercial application.

[St.Roymond]

@rsewell

@EastwoodDC

This article looks interesting, but I’m on mobile and can’t view it myself just now.

The paper is a representative exhibit of how conventional geology is essential for efficient planning of resource extraction, and how useless the rhetoric of YEC is for any practical commercial application.

I started into it but decided I need to wait till I can spend the time to read the whole thing. From what I did read it looks fun!

[Yes, I consider geology fun – as we said in glacial geology class, “geology rocks!”]

[jammycakes (James McKay)]

@rsewell

The paper is a representative exhibit of how conventional geology is essential for efficient planning of resource extraction, and how useless the rhetoric of YEC is for any practical commercial application.

Whoa. Not only that, but this is an example of a situation where getting the historical sciences right is literally a matter of life and death. It’s a case where trying to adjust your geology to match your ideology would kill people.

Coal miners always face obstacles in their struggle to win coal from the earth. Coal beds—normally thick, level, and continuous—sometimes pitch sharply up or down, split into layers too thin t o follow, fill with veins of clay or masses of stone, or end abruptly against solid rock. Unexpectedly, the roof may become almost impossible to support. Volumes of water or deadly gases may rush in a t the face. The risks and the costs, especially in lives, are great for miners, mine owners, and mining communities.

Locating, predicting, and controlling geologic hazards in coal seams depend upon knowing how they formed: What combination of climate, landscape, and vegetation produced coal seams and the disturbances associated with them, such as channels, splits, rolls, limestone bosses, clay and igneous dikes, and coal balls?