Tags

, , , , , ,

Corrupted image of a diatreme.

Who knows what geology lurks within?

One of the problems with using pre-plate tectonics geological papers to write articles that involve plate tectonics theory is that you wind up with incomprehensible copy and pastes, at least when it comes to en.wiki non-geologist editors writing the articles. Let’s look at another geology mash-up:

Rutan Hill (also called Volcanic Hill) is a unique geological feature located north of the Beemerville section of Wantage Township, in Sussex County, New Jersey in the United States. This hill is the collapsed caldera of an ancient volcano that was believed to be active 440 million years ago. It is one of a few sites of volcanic activity in New Jersey. Considered a volcanic plug, Rutan Hill is a rare formation of volcanic breccia and nepheline syenite and is a small protusion of igneous rock in the sedimentary rock of the Kittatinny Valley.[1]

Rutan Hill and associated volcanic features in its vicinity are part of the larger Cortlandt-Beemerville magmatic belt, which spans parts of northern New Jersey and southeastern New York.[2] This elongated region of volcanic and plutonic activity was active during the end of the Taconic Orogeny in the late Ordovician period. At that time, the western half of the Iapetus Ocean lying along the east coast of North America was closing, being subducted beneath the Taconic (or Bronson Hill) Island Arc. As the island arc collided with North America, it is thought that different rates of collision/subduction north and south of the present-day New York-New Jersey border area created stresses that led to a rupture of the continental crust.[2][3] The resulting volcanism is regarded as unusual due to its occurrence within a zone of compressional mountain building.[3]

The basics, first. What is Rutan Hill? It is a “collapsed caldera;” it is a “site of volcanic activity in New Jersey” (!!), it is a “volcanic plug,” a “rare formation of volcanic breccia and nepheline syenite,” and it is a “small protrusion of igneous rock.”

Actually, according to source [2], it’s a diatreme within the Martinsburg Formation, and the diatreme was, at some point in time,┬áintruded by a nepheline syenite plug. A diatreme, according to en.Wikipedia, is a special type of volcanic pipe, but basically it is where magma rose to the surface and explosions occured, and you wind up with a pipe filled with the debris of the explosions. This happened 100s of millions of years ago. It is not the “site of volcanic activity in New Jersey.” Source [1] (1940) does not call it a “collapsed caldera,” source [2] doesn’t mention a caldera, and source [3] is about an intrusive igneous complex, and volcanic rocks are extrusive igenous rocks. However, from our last post we may suspect issues from this.

The sources say it is a diatreme.

The resulting volcanism is regarded as unusual due to its occurrence within a zone of compressional mountain building.[3]

Unfortunately the same issue does arise! Intrusive, extrusive, silly geologists, what’s the difference? “Volcanism” in en.Wikipedia is tied to a source about an “intrusive belt.” They are not the same thing! Stop it en.Wikipedia!

This is what the source says:

The tectonic setting of the intrusive belt is unusual because it is associated in space and time with compressional tectonics of the Taconic orogeny, rather than with extensional rifting.

Well, I am not sure what the en.Wikipedia article is saying in its sentence, or anywhere else, as the article is pure babble, but it’s not saying what the sources are saying. It’s another geological en.wtf.

And possibly another DYK coming to a main page in your neighborhood.