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Wednesday, July 29, 2015

Geologic Tools of the Trade: No Monkey Wrenches Here, Only Bruntonian Motion

     Thanks, Lego Joe, of Puzzleria! fame for the suggestion to write about geologic tools of the trade, an extension from the NPR Sunday Puzzle about auto mechanics' tools of the trade.

      My two favorite field geologic tools are my Brunton Compass:

and my Estwing rock hammer:

[It did look like this when it was new:]

          And now it looks like this (rock hammer, Brunton, and Brunton case):

     The Brunton compass is used primarily to take the strike and dip of rocks in an outcrop as described in this three-minute video.

    The Brunton compass (actually the Brunton Pocket Transit) is a precision compass made by Brunton, Inc. of Riverton, Wyoming. The instrument was patented in 1894 by a Canadian-born Colorado geologist, David W. Brunton. 

      Unlike most modern compasses, the Brunton Pocket Transit utilizes magnetic induction damping rather than fluid to damp needle oscillation. 

     From the Wikipedia article on the Brunton Compass:

      "With the advent of portable electronic devices a new generation of compasses has emerged, some again of specific interest to geologists. Unlike analogue compasses, a digital compass relies on an accelerometer and a teslameter, and may provide much information as to the reliability of a measurement (e.g. by repeating the same measurement and performing statistical analysis). Programmers of today's smartphones have responded with different geological compass apps. However, caution must be exercised: Because the Earth's magnetic field fluctuates rapidly, 'smartphone' 3 axis magnetometers can potentially measure noise. Furthermore, all smartphones create strong magnetic fields that must be corrected by computer algorithms. At present, all geological compass apps should be tested against traditional magnetic compass measurements."

     My trusty Brunton was also used for siting along with a plane table and alidade in barite mapping in Mexico. Here's a photo of Francisco who was my bodyguard and occasional rod man 

while I tromped around on the rocks, measuring strike and dip, sampling thick barite beds, and dropping acid 
(a mixture of Alizarin red S and potassium ferricyanide dissolved in a dilute hydrochloric acid solution)

 on rocks to determine if the carbonate was calcite (bright red or pink) or dolomite (white, brownish-grayish-greenish or clear). 

       I used my Brunton to measure the strike of metamorphic features in addition to sedimentary layers. The Brunton is still used by geologists, archeologists, and other scientists (though the price is now between $350-$700; I bought mine used for $75 and that was a really good deal.)

       My rock hammer has pounded on rocks from Spain to Mexico to all over the U.S. Field geology is a truly a blast!

       Two of my other favorite "tools?" A tractor and a backhoe used to dig trenches to get a better look at the thick barite beds beneath the surface in Cobachi, Sonora, Mexico. 

What's your most trusted tool?


  1. Nice write-up on the Brunton compass, Steph! I liked the photo of the back, with the list of tangents, right over the picture of a tan gent.

    The only personal medical tool I use regularly is my Littmann Cardiology III stethoscope, which I've already had to replace at least once. (I'm not counting the otoscope and ophthalmoscope that hang on the wall in the exam room, surgical instruments, X-ray machine, and other stuff I don't own.) But, honestly, I'd rather practice without that than without my iPhone, which I need to look up drug dosages and interactions, contact info for referrals, ICD-9 code for billing, etc., dozens of times a day. And it even has a compass!

    1. Yes, stuff we can look up on the internet now is very handy. I did like working without it though in the field. GPS now makes mapping easier and more accurate. It would beat waiting months for a local company to fly over the area for aerial photographs for a base map.

      Is the compass reliable? Any issues like those mentioned above in the Wiki article?

  2. A backhoe! Now we're talking fun tools! Nothing like that in my current profession. Now, in my past lives, I've used a jackhammer (to help break up a grad school advisor's driveway), which is pretty cool. As an undergrad, I learned to use an old electron microscope, which was also fun, in a different way. An oscilloscope is always handy, too.

    1. Driving the backhoe was so much fun. I've tried both an SEM and an oscilloscope. Maybe a jackhammer next?! ;-)

  3. Update from Peace Corps Ethiopia:

    During his visit this week President Obama gave a few shout outs to “one of the largest Peace Corps Programs in the world.” During a toast at a State Dinner with Prime Minister Hailemariam Desalegn, President Obama gave thanks to both the Peace Corps and the wonderful support offered from the people of Ethiopia. “Ethiopia kindled a commitment to service for generations of young Americans who volunteered for the Peace Corps and who have for decades worked alongside the people of this proud land.”

    Zoe's adventure in Ethiopia has some parallels to my field geology time in Sonora, Mexico. What a great time for her!

    I wonder what tools she will use in her explorations there. . .

  4. Steph,

    Zoe's most valuable tool is probably her Brunton compassion.

    Great job on the blog this week! I loved learning about the amazing Brunton compass. Never heard of it before. The Estwing hammer reminds me of of a profile picture of some kind of wading bird (maybe an egret?).

    As I read your excellent text I grew a tad concerned when I came to:
    “Here's a photo of Francisco who was my bodyguard and occasional rod man while I tromped around on the rocks, measuring strike and dip, sampling thick barite beds, and dropping acid…”

    What? Steph was sharing LSD with Dennis Rodman!

    But then I continued reading:
    “… acid, (a mixture of Alizarin red S and potassium ferricyanide dissolved in a dilute hydrochloric acid solution) on rocks to determine if the carbonate was calcite (bright red or pink) or dolomite (white, brownish-grayish-greenish or clear).”

    …and I realized my concerns were unfounded.

    The tools I love most are woodworking tools. My dad was an amateur woodworker, and harbored a Shopsmith saw, band saw and other nifty tools in the basement of our home. My brother Mike salvaged the Shopsmith and still uses it. I made a pitching machine out of the band saw as a high school science project. I love jigsaws also, but am not a big fan of jigsaw puzzles. Apparently I like cutting things up (and cutting up).

    And I get anxiety pangs if I go too long without a dictionary (the ultimate tool) at hand.


    1. Thanks again for the suggestion, Lego! It was fun to write this week's blog.

      And thanks for your thoughts about Zoe in Addis Ababa.

      I agree about a dictionary though I usually use an online version now (I miss paging through my unabridged dictionary which is now much more abridged).

      We'd love to see photos of your pitching machine made with a Shopsmith Saw. That looks like a serious sawer, Tom!

    2. And the wading bird comment about the rock hammer shape was spot on!

    3. I dunno about an egret. Looks to me more like the elusive Ivory-billed woodpecker.

    4. I can see the resemblance, jan. Wish I could actually see an Ivory-billed Woodpecker, though.

    5. Good luck with that. Saw a bunch of pileated woodpeckers while hiking in upstate NJ on Sunday, and who can really tell them apart at a distance?

    6. They are smaller, right? Will need to bring along my rock hammer to check the shape of the bill and pileation. ;-) Are any other birds deemed "pileated" besides a woodpecker?

      Also, if there's not been a confirmed sighting of an IBW since 1935, isn't it likely any, or certainly most, photos of live IBWs are colorized? Wikipedia discloses this on their image but the page I cited does not.

    7. Seems like the term is basically the same as "crested". There are pileated finches, antwrens, parrots, flycatchers. And gibbons, which don't look so crested to me.

      You could also use your rock hammer to check the size, as I read they're used for scale in photos. Or to beat them off, in case they're angry about being driven to extinction. Lots of people waste time on angry birds, I hear.

    8. I'd only known of the woodpecker; well, and the toothpaste before.

      A geological engineer (NOT a geologist) at field camp used to carry a miniature 3"- long rock hammer for photos to make things appear bigger.

      Glad we are carefully using our time here at PEOTS instead of mixing it up with the mad avians.

    9. jan,
      I now regret saying an egret resembles an Estwing rock hammer, after viewing your and Steph's Ivory Billed Woodpecker links. In any event, the rock hammer resembles a creature with two Estwings.


    10. Two Estwings ;-).

      Gorgeous white bird images, Lego!

  5. My Dad was quite adept with a scythe. He tried to teach me once and ended up taking it away from me before I hurt myself.
    A grass whip is more my style. I used to find it effective during those times when only this was wont to grow.

    Well, better than hitting a bucket of balls, I say.

    1. Wow, Paul, that grass whip is cool! Looks exactly like hitting a bucket of balls. . .but with more satisfaction (for me, anyway).

  6. I'd like to see that band saw pitcher.
    If it dips just as it crosses the plate, it's bound to be a strike.

    1. The cleverness quotient today--wow. From tan gents to Brunton compassion to dipping, crossing, and striking--fun!

      Yes, band saw pitcher pictures please, Lego.

  7. Conspiracy theory:

    Of course, the 777 flaperon that washed up on Reunion Island has to be from MH 370. Unless...

    ... the Russians have the intact plane, and planted a flaperon from MH 17, the 777 they shot down over Ukraine, just to throw everyone off the trail.

    1. So much flap over a flaperon? (Someone had to say it).

      Now I am learning about spoilerons.

  8. Violence in the streets of dwarf planets:

    Found this on comp.risks:

    A quick reminder that spelling checkers do not catch everything.
    A recent NASA press release about New Horizons contained the sentence

    "Ultraviolent sunlight chemically converts hazes into tholins, the dark
    hydrocarbons that color Pluto's surface"

    It was fixed in the meantime on the NASA web site, but other sites still
    carry it. Of course, instead of a simple error, it could also be a Douglas
    Adams quote...

    1. UltravioleNt--OK, that took me a few minutes. . .

      It could be D.A. quote!

    2. Me too. Had to look up "tholin". (Wasn't he a dwarf pal of Bilbo?)

    3. I searched tholins, hazes, and hydrocarbons before the extra 'n' hit me.

      'Thorin/Tholin' I got right away however. . .

    4. I tend more toward infraviolence, but normally I just hide in plane sight.

    5. Huh. Infraviolet. What a day. What a fuchsia kinda day. Plane sight, Paul? Plain cite. Plane Cite. Always more to learn (thankfully).

    6. Yes, thankfully, for both. Thanks, Paul!

  9. I am completely unhandy with my hands, but while in college, I was highly dependent on my slide rule.

    1. David, do you still use/have your college slide rule?

    2. Where do you keep your slide rule?

      My Brunton and rock hammer are always handy in my car though I don't use them as often now.

  10. You bet your sweet [Keuffel and] Esser I still have my college slide rule. But, as I said, I now rely on my iPhone. It's my electric slide rule.

    1. That was really fun. Maizie and I started dancing. Such a great dance song. Loved the guys in the black tops and black, white, and electric pink pants.

  11. Puzzleria! is uploaded. Four fresh puzzles plus one easily digestible puzzle appetizer.

    ‘Tis a shame that the slide rule was not named for someone, like Estwick or Brunton, even though it is now pretty much a mechanical dodo that most people don’tdon’t use anymore. According to this Wikipedia account, a slide rule might have been called a “Napier rapier” or perhaps an “Oughtred reckoner.”

    As for my band saw pitching machine, alas no record of it exists. If we took a photo, it has probably bit the dusts of time. 8-millimeter movie film? Possible, but not likely. I built in in the spring of 1969, as a high school senior. I used it that summer and the summer of 1970. I also build a backstop in our back yard and spent countless solitary hours facing it down, man versus manmade machine.

    By the summer of ’71 I had stopped using my mechanical nemesis, my heart no longer in it. Until then I harbored youthful illusions that I would someday become a major league baseball player. When I tried out for my small college baseball team in the spring of 1970, but did not make the cut, I imagined Harry Carey, Vin Scully or some other radio play-by-play man saying at some future ballgame, “Can you believe that Joseph Young, this phenom and Triple Crown candidate, was actually cut from his college freshman team?!” When I didn’t make the team as a sophomore in 1971, I stubbornly but finally realized that my baseball future was not in the Cards… or Mets, Yanks, Phils, A’s or Sox, Red or White. My pitching machine sat silent and still. Cobwebs formed. Salvage loomed.

    Perhaps in next week’s Puzzleria! (where I can post pictures) I will try to recreate the parts and cobble together a pictorial facsimile of the machine. I’ve Duck Duck Googled a photo of the old band saw I used, including the moter, which I had to “gear down.” Other parts were mostly metal: pulley wheels (w/ black rubber pulley belts) and axles, springs, a piece of slotted angle iron (seemingly from Paul Bunyan’s erector set) that served as the pitching arm, and a section of bicycle fender (the pitching hand). The heart of the machine was a ball bearing that was attached near the base of the arm and served as the machine’s fulcrum; I bought it for $5 at a machine shop in Eau Claire.

    I called my brother, Mike, last night to pick his memory about what I built back in 1969. Mike is the real mechanic in our family, and has the tools to prove it… including, as it happens, a spare band saw. So I hit upon a crazy idea: relive 1969 and recreate my pitching machine! Heck, I did it once.


    1. Good to learn about Oughtred and the slide rule, Lego.

      Looking forward to pitcher perfect photos and/or recreations soon either here or at Puzzleria!

    2. Motor!

      motor: a machine, especially one powered by electricity or internal combustion, that supplies motive power for a vehicle or for some other device with moving parts.

      moter: one who makes molehills out of mountains


    3. Alternate definitions for Moter:

      1. One who tries to get across a moat

      2. One who shows emotions in real life, rather than online (as in e-moter)

      3. A place to stay overnight where the top of the 'L" was shot off and a little piece of rust formed to the right of the top of said letter

    4. Or an alternate term for Moties, the aliens in The Mote in God's Eye

    5. Just read the synopsis and am adding that one to my list (wonder if Blaine has read it with Commander Roderick "Rod" Blaine) together with:

      "Cutting for Stone" by Abraham Verghese

      "When the World Calls: The Inside Story of the Peace Corps and Its First Fifty Years" by Stanley Meisler

      "Notes From the Hyena's Belly" by Nega Mezlekia.

      Any other good recommendations for this brand new moñth?

  12. Replies
    1. So
      sarcasm may be an effective tool
      moral of the story
      trust needs to be placed elsewhere
      just an hypothesis

    2. Quite true. Trust is an important part of teamwork. I have been known, on occasion, to equate sarcasm with wit or humour, and they truly aren't the same. If you replace sarcasm with wit (even biting wit?) or humour, the article works better for my own "teamability." How about you, fellow PEOTSers?

      Also, Paul, I am researching your "sintering compact surfaces" question over at Joe's Puzzleria! A potter friend and I were talking about this very topic, fossil fish, and kaolinite over Ethiopian coffee yesterday. I may both post places as it is PDI.

    3. Sintered compact surfaces, as you may know, are factory made slabs of clay, silica and feldspar which are subjected to high temps and pressure without melting. The building industry has been using these slabs in place of natural metamorphosed rock (marble, gneiss, etc). The beauty of natural slabs with unusual markings is not usually seen as the maufactured slabs tend to be more uniform. There is the benefit of not using up the natural rock and the fact that the slabs can be uniformly load-bearing at much thinner thicknesses.

      I like looking at the labradorite crystals in my blue-eyes granite countertops and seeing how different it is at various spots. It was also fairly expensive and needed to be much thicker.

      I could see places and times for the natural and the fabricated.

      How's that for sitting on the fence, Sinterella?

    4. And yet you still haven't chipped out a chunk and placed it under your pillow at night?
      I guess there's no accounting for some people's priorities.

    5. No, but I do have a fairly large leftover slab just sitting in my garden near the Cosmos. Maybe I ought to bring that in and place it under 2-3 pillows (it's likely pretty hard to sleep on, I'd think).

    6. You've got the cosmos in your garden?

      Why should I be surprised?

    7. That's Cosmos, the wonderful, colorful flower. . .You can see the whole cosmos in them, though. . .But, you knew that, right?

  13. Thanks to PEOTS and Oliver Sacks, I was able to explain the bottle of zinc supplements that someone got my son for his birthday

  14. New post on "Mugo Pine and The Redheaded Pine Sawfly: Counting Pro-Legs and Looking for 'Crochets'" is now up.