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Apollo 11 50th Anniversary: The Lunar Minerals

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The MOOOOOOOOON!!! (image: Wikimedia ) 50 years ago today, Apollo 11 accomplished the bold feat of landing on the Moon and not only did they walk on the Moon, they brought back some of it with them on their return for study. Some bits of lunar rock found their way to becoming thin sections, which you can view here , and occasionally get loaned out to researchers outside of NASA. I was lucky enough to handle and view some of these thin sections in my undergrad Igneous and Metamorphic Petrology class, as well as a thin section of a Martian meteorite (the closest I'll ever get to being on Mars). The lunar rocks have been well-studied by geologists over the years and Mindat.org has curated a list of minerals found on the moon, almost all of which are also found on Earth. The Moon can, in a broad sense, been generalized into two types of igneous rocks: basalt and anorthosite. The bright, white-grey parts of the Moon are the anorthosite dominated areas. These are feldspar-rich ro...

The Research Diaries #2: Field season!

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Measuring section and bagging samples in Marion County, Arkansas looking for clues from the Ordovician in some cherty dolostones. When you can't find a Jacob's staff in the office, you grab a broom stick and make your own...with black, semi-goth duck tape! Now to figure out how to cut slabs, make thin sections, and make sense of these weird tan lines.

Historical Topographic Maps of Fayetteville

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Of all of the many types of maps that have been made for one purpose or another, I find one of the most enjoyable kind to look at are the old USGS topographic maps. These types have been made since 1879  (which also was the year that USGS was established) and thus, depict the human world that once was. This is particularly interesting since many localities have been mapped three or more times and we can see the evolution of human geography. For this reason and because I grew up within two miles of two towns that were abandoned during the 1960s as a dam was constructed and flooded the town sites, I'm easily fascinated by old maps that show towns and other old settlements and structures that have been abandoned. Old topo maps from across the country can be viewed and downloaded for free (in JPEG, TIFF, or PDF formats) from the USGS ( click here for more ). Admittedly, this USGS site is a huge rabbit hole for me to fall into and I've downloaded several topo maps from it, inc...

Ugh....Social Media

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On a rare occasion when I visit Facebook, I'll run across a post on my feed from someone who, for good humor or not, has shared an image, video, or link related to geoscience. Naturally, that makes me very happy and almost willing to comment on social media (I don't usually partake in many social media platforms and I try to keep my opinions on various matters personal). However, I have seen a few posts that are misleading or outright false that I will call out. One such is this image does raise an interesting question: No doubt that this image or variations of this image have been spread around on the Internet, and of course this is all in good humor. But, this is nevertheless poorly worded. Statement #1: "Those [countries] who use the Metric System" Firstly, "Metric System" doesn't need to be capitalized. Yeah, sure it's nitpicking, but I had to say it. Secondly, the US adopted the British system of measurements and altered them a bit to...

New NASA Mission Announced: Titan

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    Today, NASA announced a new mission , this one to one of Saturn's many moons, Titan. Titan beckons a visit from humanity so she can tell her tales to us. It is the 2nd largest moon in the solar system; slightly smaller than Jupiter's Ganymede, but still bigger than Mercury. With a thick atmosphere that is "four times denser than Earth's" and is much colder temperatures (appx. -290° F), some wondrous geologic and atmospheric processes are actively shaping the surface, such as raining freakin' methane (CH 4 ) and ethane (C 2 H 6 )!  Yeah, these molecules of carbon and hydrogen, combined with a nitrogen rich atmosphere (like Earth), are very important to the creation of life as we know it (on Earth anyways), and they just lay around as liquid  (not gas!) on the surface of Titan in rivers and lakes of hydrocarbons. While methane and ethane are produced by living things (e.g. aromatic farts), it can easily be produced through natural geologic processes just as...

The Research Diaries #1

While researching dolomite, I read this delightful bit in the journal AAPG Bulletin : "Furthermore, the feasibility of this, or a similar system was recently demonstrated (unintentionally) by a male dalmatian who produced uroliths [essentially kidney stones of the bladder] of ordered dolomite in his urinary bladder." That is a sentence that I never thought I would read in a highly respected geologic research journal. Previously, I would have thought that a dalmatian would exclusively be a subject in either a medical or biological study, not a geological study. I stand corrected. This also raises a series of questions: (1) Was this the author's dalmatian? If not, who's dog was this? (2) What provoked a geologist to look at the uroliths, especially if it was from someone else's dog? (3) How did someone find the stones? Did someone wait for the uroliths to pass, did someone dig around outside (or inside!) in a puddle of pee, or were they retrieved via surg...

Arkansas Commemorative Stones in the Washington Monument

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    Hidden along the scenic Highway 7 in the community of Marble Falls (formerly called Dogpatch) in Boone County, Arkansas is a small abandoned limestone quarry of monumental proportions (pun intended). Within the Washington Monument in Washington, D.C. are three stone blocks that represent Arkansas. These are among 190 other commemorative blocks that were set into the monument during and after its construction. Each state, as well as several organizations and persons, are represented in these blocks. For Arkansas, the State itself is represented, as well as the City of Little Rock, and the Grand Lodge of the Masons. The Masons of Newton and surrounding counties intended to be represented as well, however, their stone's whereabouts are unknown. The Arkansas commemorative stone. Photo from NPS .     The first of the three stones was quarried in Marble Falls in either 1834 or 1836 (two sources have competing years). The year 1836 would have been particularly s...

Building Stones of Gearhart Hall

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Gearhart Hall (photo credit: Robert A.M. Stern Architects )     Gearhart Hall has a long history that began with its construction in 1937-1940 and has had many names. Its history described in an application for the National Register of Historic Places is as follows [ 1 ] : [Gearhart] Hall was constructed in 1940 as the "Classroom Building" in the Collegiate Gothic style. The stone building with an irregular floor plan features a principal front section with a central entrance and two rear "T" sections. The cut-stone walls are supported by a continuous concrete foundation. A central projecting bay dominates the building's façade, and features a three-sided oriel window over the entrance. A crenellated raised parapet surrounds the flat roof, like most of the other limestone buildings built on campus during this period.  The second phase of what is called today [Gearhart] Hall, completed in 1947, was designed and sited to connect the Classroom...

Periodic Minerals: Galena

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    Another periodic mineral post! Since the last one was realgar, an arsenic bearing mineral, I thought I'd continue the theme of toxic minerals with galena. Galena is a very dense lead sulfide mineral (the chemical formula is PbS) and is the primary ore mineral that is mined for lead. Typically associated with zinc minerals such as sphalerite (ZnS), lead has long been mined in the US since the colonial period, but today there are only  ten mines in the US that currently produce lead . Five of these are in Missouri (the Brushy Creek, Buick, Fletcher, Sweetwater, and Viburnum mines), two in Alaska (the Greens Creek and Red Dog mines), two in Idaho (the Galena and Lucky Friday mines), and one in Washington (the Pend Oreille mine). Although, there has been recent discussion in late 2018 to re-open the Bunker Hill Mine in Idaho. However, the Bunker Hill Mine is next door to the second-largest EPA Superfund site which houses the Bunker Hill smelter complex and tailing piles...

Recommended Podcasts: The Dollop

If you're interested in podcasts related to geoscience, check out The Dollop . The Dollop is a history podcast hosted by two comedians where they discuss some odd topic, event, or person from history. Most of the episodes are about 40-70 minutes in length with a few that are longer. A few episodes relate to Earth science (with a brief synopsis): #60 - The Comet Panic Many terrible "scientific" studies and sensationalized news headlines caused some people to fear the return of Halley's Comet in 1910. #80 - Hollow Earth The bizarre pseduoscientific belief that the Earth is hollow was promoted by a guy named John Cleves Symmes Jr. in the early 1800s. #132 - The Bone Wars The bitter and longstanding feud between paleontologists Prof. Marsh and Prof. Cope during the 1870s to 1880s. #151 - The Oil Boomtowns of Texas The wild booms and busts of the late 1800s to early 1900s and the fight between private industry and government regulation. #235 - The Great Diamond Hoax...

Recommended Podcasts: 99% Invisible

The podcast 99% Invisible delves into the stories of people, places, and objects that people tend to overlook. Many of these unusual topics are related to technology, architecture, history, and artwork, among several other fascinating subjects. It is a high quality, well-produced podcast done in a similar fashion to many NPR segments with each episode lasting about 30 to 45 minutes. I mention this because there are a few episodes that are related to Earth science: Making It Rain Past and present attempts to alter the weather from rain dances to geoengineering. The Vault The seed vault in northern Norway where plant seeds from around the world are stored in case of war, drought, or other national or international stress. Fire and Rain Past and present California wildfire prevention measures and their effectiveness. Welcome to Jurassic Art The changing perception of dinosaurs depicted in art from lumbering, lethargic reptiles to feathered, lively creatures. Crude Habit Re-purposin...

Dolomite or Dolostone?

Geologists frequently use the term dolomite to describe both the mineral and the carbonate rock that is comprised of that same mineral. However, I find this to be unnecessarily confusing, especially since a clear distinction between calcite and limestone is recognized. So, I've dug up some history to the term dolomite . In 1768, Swedish natural scientist and “father of modern taxonomy”, Carl Linnaeus (later known as Carl von Linné), briefly described a type of rock he called marmor tardum , translated as slow marble . Marmor tardum , Linnaeus says, is a white marble that is as hard as quartz, but slowly effervesces potentially describing a dolomitized marble. Italian geologist, Giovanni Arduino, also described a marble in 1779 that has been considered to be dolomitized. However, it wasn’t until 1791 that a more complete description of dolomite was published by French geologist Déodat Gratet de Dolomieu, who described dolostones in the Alps (a region then called County Tyrol) ...

Periodic Minerals: Realgar

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Realgar (red) with quartz and pyrite. I was thinking of periodically posting about some particular mineral, fossil, or rock (particularly when I don't have a topic to discuss), and I thought that realgar would make for a good mineral to discuss. Realgar is an arsenic sulfide mineral with the best chemical formula I've ever seen: AsS (sometimes written As 4 S 4 ). It's very soft ( hardness 1.5-2 ) with a brilliant red color and a resinous, greasy luster  and is associated with hydrothermal ore deposits. Several fantastic specimens of realgar come from Paloma, Peru (such as the one pictured). Interestingly, realgar reacts to sunlight. I don't understand exactly how this happens, but given some time in sunlight, it will alter to a yellow-orange mineral called pararealgar. So, if you collect a sample of realgar, keep it in a dark box or drawer. I didn't know about this when I got my sample (pictured), but I've been fortunate to not have enough space to displa...

Odd Stratigraphic Names

The USGS has a great website for searching stratigraphic names and I've found some names that are a little different. I've listed some of the most interesting ones below. Note that many of these are from the western states, and there's a reason for that. Names of lithostratigraphic units (groups, formations, members, and beds) must named after a geographic locality, such as a county, town, river, or mountain, per the nomenclatorial rules set forth in the North American Stratigraphic Code . Many of the geographic localities in the eastern US are more puritanical, if you will, from early European settlers, while the western states settled in the mid- to late-nineteenth century were named more loosely. Also, note that not all of these names are currently in use, some of these names may have been abandoned in favor of another name(s) and others may have been proposed, but not formally accepted for one reason or another (e.g. it must have sufficient reason for naming the unit,...