Conglomerates for Dummies

Depending on who says it to you, the adage is either "God in in the details" or "The Devil is in the details." Either way, it should be pretty obvious that it's really the details that are important; the big picture is only a rough outline. In their travels around the 'net, our staffers often find freelance posts that get the basics right, but botch the details. That seems to be especially prevalent in posts that originated at eHow.com, perhaps because the freelancers were forced to embellish stuff in order to meet the minimum word count. Today's nominee is one such eHow post, "The Difference Between Metaconglomerate & Conglomerate," a Mitchell Land contribution to Sciencing.com.

The geologists on our staff all agree: a metaconglomerate is different from a conglomerate only in that the metaconglomerate has undergone metamorphism. It still, however, retains the texture of a conglomerate, i.e., clasts in a matrix of finer-grained material. That's about it.
Land could not collect his eHow stipend for that 31-word answer; no, the young theater/French major had to expand it to at least 300 words (he darned near hit 400). Mitchell's problem? He didn't know enough about geology to avoid some... stupid stuff. We're talking stuff like,

• "Conglomerate and metaconglomerate rock begin as particles of rock and sand collected in the sediment of streams, rivers or oceans." — Oceans? Not so much. That, and Mitch left out alluvial fans and glacial till, some of the most common sources of conglomerates.
• "Conglomerate and metaconglomerate differ in formation and physical characteristics." — We don't even know what that means.
• "Rock with a high amount of silica and silicates that is made of preexisting rock material is referred to as siliciclastic." — Well, yeah, but what does that have to do with conglomerates? There are, after all, conglomeratic limestones...
• "Conglomerate rock is a mix of large and small grains and is siliciclastic sedimentary rock. It is also comprised of small rock pieces held together by a fine-grained matrix." — Redundant much?
• "Metamorphism increases the density of the original conglomerate rock by compacting the grains, and can also change the color with mineral interaction." — Ummm, no.

• "...matrix is comprised of sand or silt and cements the rock together" — No, cement cements the matriix and the clasts.
• "In metaconglomerate rock, the original pebbles may be stretched or flattened. The metamorphic rock is denser and cannot be easily broken." — Maybe, maybe not. What would be useful is a mention of the recrystallization that often makes metaconglomerates harder.

Land was clearly one of the many scientifically illiterate freelancers who contributed to eHow, and adopted a technique common among his fellow illiterates: he threw as many factoids at the screen as he could find, hoping that that some would stick... and that an equally illiterate content editor would give him a pass. The CE did, but we don't: give a Bronx cheer for our Dumbass of the Day!

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