Discovering Geographical Information Systems: Quantum GIS

I had gotten frustrated with creating site maps in AutoCad 12 LT, and yesterday’s field work was postponed because of rain. Additionally, Quantum GIS software is free. This turned out to be a great combination.

Not to bash AutoCAD 12 LT (for non-technical readers – AutoCAD LT is the “Lite” version of a common engineering drafting software program)- it’s been great for creating site maps for industrial clients who can send me their base plans already in AutoCAD format. I add some new layers for their hazardous waste locations and protocols, drop it into my company’s standard frame, and voila. However, I was going back to my company’s decade-old protocol for mapping monitoring wells in AutoCAD and found it cumbersome. In order to make an accurate map I had to take a screenshot of Google Earth, save it, attach it as an external reference file, adjust the raster DPI so it didn’t look like an 8-bit video game, and then set the layer properties so it wouldn’t accidentally be moved while I added feature points. With that done, I had to go back to Google Earth and transfer a scale – and good luck if I had zoomed the map to fit the site boundaries while in AutoCAD. Once the well locations and site outlines were traced, I would delete the base map. I figured that there had to be a simpler way to do this.

I got the decisive nudge towards exploring Quantum GIS from a geologist friend whose specialty is managing complicated Oracle/ESRI ArcGIS systems.   We were having our usual nerdy kind of conversation over dinner on Friday (planetary plausibility of Star Trek, using radar to map the subsurface of Mars, oil pipelines, etc) when I brought up my mapping conundrum. I had been using the free version of Google Earth Pro but it lacked some of the features I wanted, and he suggested QGIS as the next step up.

Quantum GIS (QGIS) can be downloaded here.

I will freely admit that even though I had done some basic cartography in ArcGIS a few years back, I had little idea what to do next. QGIS has a graphical interface comparable to AutoCAD LT, actually – helpful enough but not completely intuitive. Luckily, there’s an instruction video for pretty much everything on YouTube.

qgis-intro-video-capture

Klas Karlsson created a clear, concise, and useful walk-through of a basic project – you can find it here.

Next I wanted to find a general overview of what the software could do – which“A Gentle Introduction to GIS” by T. Sutton, O. Dassau, and M. Sutton of the Department of Land Affairs of South Africa does nicely. This free text serves as an introduction to geographical information systems in general, but focuses on QGIS. It does a good job of making the software less intimidating, answered my questions about the cartography projections I had to choose between,  and gave me a basic view of the analytical capabilities I can learn in the future.

So, to compare map outcomes (…drumroll…):

Estimated water table surface map made with AutoCAD 12 LT:

tipton-map-snipautocad

Versus a map of the same site made with QGIS (client data blurred out):

tipton-map-snipqgis-no-numbers

This landfill in West Tennessee hasn’t had any contamination in the years my employer has been sampling here – good for the planet and keeping my job simple!

For now I drafted the water surface elevation contours and flow direction by hand and then digitized them, as my company has done in the past. However, I know that somewhere in the jungle of optional plugins there’s a way to make QGIS create groundwater contours based on my data points. That’s going to take more than an afternoon’s study to master though, and I look forward to getting to that point!

Advantages to AutoCAD LT:

  • Ability to draw splines/curved lines, easily rotate shapes and text
  • Faster rendering time between zoom frames
  • Option for typed commands instead of click-and-select
  • Format is widely used across engineering and environmental consulting fields

Advantages to Quantum GIS:

  • Base maps are so easy to insert, delete, and switch out!
  • Ease of entering attribute data, and ability to make any variable of that attribute data a visible tag on a feature location
  • Can enter well locations based on the coordinates measured in the field
  • Easy to measure distances
  • Instant scale
  • Instant and easily modified legend
  • Spatial analysis, once I figure out how to use it
  • FREE

After this intro I’m hooked on the possibilities of QGIS. I’m seriously tempted to digitize my hand-sketched field camp maps and start using it for my Phase I Environmental Site Assessment maps…

I definitely have enough left to learn to fill many a rainy day to come.

How do you use GIS in your work and research? I’d love to hear about it in the comments.

I defeated the ASBOG FG!

All three times that I went to the Geological Society of America conferences, I picked up something from the Association of State Boards of Geology (ASBOG) booth. I won a rather nice tape measure from them in 2015. All three times, the booth staff admonished me with “you should take the Fundamentals  of Geology exam before you forget everything you learned in university!”.

And then I found myself thinking in the summer of 2016 – what am I waiting for? I took all the necessary coursework and more that I need to be licensed, I’m working under two licensed professional geologists, why not take the exam and get on the path to making all that work official?

I ordered the RegReview study guide, said farewell to my three-times-a-week climbing gym habit so I would actually make time to study, and got to work.

I really should have taken it right out of college, but wasn’t as rusty as I had feared. Even though I felt like throwing my study guide across the room after the fourth page of ore mineral formulas, studying for the exam actually reminded me why I want to be a geoscientist. One night I was messing around with formulas for mapping groundwater draw-down and projection of cross-sections onto a map view and didn’t realize that it had gotten to be 1 AM. (I had to get up to be at a job site at 6 AM. Oops.) I got to spend quality time with fields like seismology and structural geology that don’t show up often in my day-to-day work.

Not to mention that my sister drew me this gem of a Lord of the Rings/Geology crossover: Meet the ASBOG Balrog.

img_2172

So that’s how I found myself at 7 AM at the Department of Commerce building on September 30 armed with a calculator, protractor, and 1 liter thermos of steaming hot caffeine. Walking through the door, I could immediately identify my fellow geologists waiting for the exam – plaid shirts, practical shoes, Patagonia vests, and looks of acute anxiety were all giveaways among steady stream of state employees heading to the elevator.

We all walked out of the exam room four hours later, exhausted and convinced that we had failed. Thankfully, today I found out that I actually passed! With acceptable marks in all categories, even the ones I was freaked out about! (I’m talking about you, engineering geology)

When I was studying for the exam, I scoured google and reddit for advice from people who had taken the exam, and couldn’t find much. Much of the advice pertained to the second exam, (the PG), like this excellent blog post over at Accidental Remediation. In the hopes of helping someone like me taking the FG, here are some of the things I found most helpful:

  1. There is no way on earth that you can cram for this exam. I did one chapter per week in the RegReview book, and that was almost pushing it. I should have started studying earlier – the ASBOG website isn’t joking when is says six months in advance.
  2. Take a close look at the application to take the exam. I got taken by surprise by the fact that after I had submitted my exam to my states professional licensing board, and I had to submitted a completely different application and fee to the national ASBOG organization.
    1. step one: State of Tennessee Geologist Licensing Forms (or your state’s equivalent). For Tennessee, this meant filling out two forms: the Geologist FG Exam Application, and the Geologist Course Reporting Form.
    2. step two: after the application is accepting by the state board, that agency will send you a candidate request form that you will need to send, with a check attached, to ASBOG.
  3. The actual exam questions were slightly easier than the ones in the RegReview book, and didn’t need quite as much math. However, they were still by no means easy. Looking back at my university quiz and test questions, the ASBOG questions were comparable to the more difficult 25% of them. They were very similar in difficulty to the questions in the official ASBOG candidate handbook.
  4. Memorize the picky mineral characteristics/formulas and mining terms. They were on the exam, believe it or not.
  5. Don’t underestimate the power of handwritten notes…
  6. …or flashcards, either. If you use the RegReview cards, add in a few additional handmade ones for ore deposit types, water quality standards, dating methods, Bowen’s reaction series, and engineering characteristics of earth materials (elastic properties, etc).
  7. And then working the practice problems a second time.
  8. I don’t recommend bothering to study in the two days immediately before the test. I know I was too keyed-up for any more information to stick, anyways.  Eat well, try to get some sleep, and do thing that clear your head. In my case it was lunch with an old friend and wearing myself out on the rock wall.

Have you taken the exam? What impacts have being licensed (or not) had on your career? I’d love to hear your opinions in the comments.

 

 

 

 

Water in the wilderness: China’s growing deserts

tengger-desert

The Tengger Desert, courtesy of crienglish.com

I ran across an article that took my breath away.

Living in China’s Expanding Deserts: New York Times by Josh Haner, Edward Wong, Derek Watkins, and Jeremy White.

The drone footage of the contrast of humanity and desert, of children playing in the sand and improbable greenhouses, was absolutely beautiful. Finishing it was something like eating a delicious, carefully plated appetizer and then finding out that there’s no main course to follow it.

Don’t get me wrong, it’s wonderful journalism about a region I’ve always been fascinated with. I was left, though, with questions. What was life like there beforehand? Why is the Tengger desert expanding, and how fast?

Many of my questions will probably have to go unanswered, as I understand exactly 0% of the Chinese language. However, I found some interesting further resources on the area.

Another great article on desertification in Inner Mongolia, with more of a focus on economic and environmental drivers of the desertification than the New York Times feature: Waterless World: China’s ever-expanding desert wasteland by Benjamin Carlson

Cue angelic singing, I finally found an scientific article on groundwater resources in this area written in English:

Currell, M. J., Han, D., Chen, Z. and Cartwright, I. (2012), Sustainability of groundwater usage in northern China: dependence on palaeowaters and effects on water quality, quantity and ecosystem health.Hydrol. Process., 26: 4050–4066. doi:10.1002/hyp.9208

One of the lead authors also wrote an article for China Dialogue – The Shrinking Depths Below – that serves as an introduction to his research and an excellent summary.

A thorough break-down of desertification effects and probable causes by region in China can be found over at here at GeoCases.

Further to the northeast of the area covered in the NYTimes article, the coal processing activities which have lead to huge economic growth in Baotou City in Inner Mongolia have also sucked water away from their prior uses. I’m looking for more sources on this, but this GreenPeace video initially piqued my curiosity.

https://i1.wp.com/www.chinamaps.org/images/china-map/maps-of-china/china-map-of-precipitation.jpg

An annual precipitation contour map of China, from http://www.chinamaps.org. Areas in bright yellow to orange have less than 200 millimeters of precipitation per year, and are considered deserts. The area mentioned in the NYTimes article is a bit west of Yinchuan on this map.

 

 

Oh, Canada! Part 3: Clay and Quakes

This is the third and final installment of overthinking of my family’s trip to Quebec. Allons-y!

Intro: Oh, Canada!

Part 1: Oh, Canada! Part 1: Monadnocks

Part 2: Oh, Canada! Part 2: Impact

From La Malbaie in the annular trough of the impact crater, our road trip headed northwest along the coast to St. Simeon to catch the ferry.

Reford to Point-de-Saint-Vallier

A small population of beluga whales hangs out in the St. Lawrence. We were lucky enough to see several of them popping up above the waves on the ferry ride!

From the ferry landing at Riviere-du-Loup we headed north to Grand Metis to see one last garden – called either Reford Garden or Jardin de Metis depending on whether you’re an anglophone or a francophone. Elsie Reford set out to build the perfect garden there in 1926, but the rolling terrain on the southern shore of the St. Lawrence wasn’t very cooperative. The local soil is a thick layer of clay with very poor drainage left behind by the Champlain Sea, an extension of the Atlantic left in the depression of the retreating glaciers between 13,000 and 10,000 years ago. The waterlogged clay hosts scenic marshes of lupins and stunted pine trees but is a significant obstacle for the ambitious gardener.

a recreation of the extent of the Champlain Sea ~11,000 years ago, courtesy of Orbitale at Wikipedia

As the Laurentian Ice Sheet retreated around 15,000 years ago its meltwater washed huge amounts of silt to the sea, which combined with marine clay deposits and the natural chemistry of the seawater created a massive layer of clay. As the crust heaved a sigh of relieve at the weight of the ice sheets being removed, that isostatic process gradually lifted the seafloor into dry land.  This garden took a lot of back-breaking work and planning to dig two- to four-foot deep beds, add in drainage systems honeycombed through the impermeable clay so the plants wouldn’t drown, and then fill in the beds with gravel and imported loamy soil. And this was in the early 1900s before Bobcat earth movers!

Mrs. Reford’s results are spectacular, though.

reford 1

Eventually, though, the time came when we had to drag ourselves out of the garden and back onto the road heading south. But we had one last stop before Quebec City – my mother’s friend’s friend Yves was taking care of a Heritage Canada property at Pointe-de-Saint-Valliers and had invited us there for dinner.  Between dinner and dessert we hiked out to the point, where Yves casually mentioned that the cliff jutting out above the tidal flats was rather smaller than it had been because of that earthquake back in ’88.

Wait what, Quebec has earthquakes?!

It turns out that between the area being torn open as the Iapetus Ocean was formed after the breakup of Rodinia, a meteor punching a crater into the crust~342 million years ago, the nearby Appalachians being built as the ocean closed fully to form Pangaea 270 million years ago, the Atlantic Ocean ripping open ~175 million years ago, and the vast weight placed and released by the ice cap in the Pliocene/Pleistocene glaciation, the crust under the St. Lawrence has had a tremendously stressful life.

 

Fault map image courtesy of Tremblay et al. 2013

All this stress is exhibited as the St. Lawrence Rift System that stretches from the Ottawa-Bonnechere Graben to the mouth of the St. Lawrence. The dramatic escarpment along the northern side of the St. Lawrence Valley was formed by grabens and half-grabens dropping down due to the extensional force created around 450 million years ago, when a carbonate platform collapsed during the formation of the Iapetus ocean. After 450 million years of erosion the resistant granites, quartzite, and marble of the Canadian Shield now make up the footwall of the graben (visible as the 200 meter high escarpment), with younger rocks making up the hanging wall.  Those late Proterozoic to early Paleozoic faults were reactivated with each successive compression or decompression of the crust.

Right now, the crust is still in the process of rebounding and decompressing after the last ice age. That localized expansion of the crust creates friction along those old fault lines – when too much force builds up for friction to resist, the rocks on either side of the faults slip past each other with a violent jolt that creates an earthquake.

In the region we were traveling, these quakes are categorized within the Charlevoix Seismic Zone and the Western Quebec Seismic Zone. Pointe-de-Saint-Valliers sits on the south-western fringe of the Charlevoix Seismic zone, where the weaknesses in the crust created by the meteor impact in addition to the late Proterozoic faults release the rebounding stress after the last ice age.

chvzone3

Imaged edited from the EarthquakesCanada site.

Luckily the fault zones were on their best behavior while we were there.

After that leg of the road trip we spent a wonderful day-and-a-half exploring Quebec City. My mom introduced me to all her favorite haunts from her childhood there. Much ice cream was consumed, because where else can you get maple ice cream with maple sugar crunch and maple cookies?!

On the way back to Montreal to fly out we found the last remaining dinosaurs in Quebec! No dinosaur fossils have been found is this region, as any rocks that might have contained them were scoured away by the ice caps. The youngest fossils in this area date from the Ordovician. But we can still dream, right?

IMG_20160628_122715682

The author joined the intrepid herd of dinosaurs at the famous Madrid 2.0 gas station in St-Leonard-d’Aston, Quebec (exit 202 on the Trans-Canadian Highway)

Bonus: When my sister and I start hanging out, silly things happen. Like a cartoon geologic history of Laurentia.

geologic comic

Oh, Canada! Part 2: Impact

Intro: Oh, Canada!

Part 1: Oh, Canada! Part 1: Monadnocks

The drive through the Charlevoix, the area on the northern bank of the St. Lawrence from Quebec City to la Malbaie, is jaw-dropping and quintessentially Canadian. Anti-moose fences running along the sides of the highway underline fantastic views of the Laurentian mountains where my cousins learned to ski. When the road winds through enough civilization for the moose fences to disappear, the civilization takes the form of adorable clapboard houses with brightly painted accents and laundry drying on the line. The entire landscape looks like it jumped out of a picture book.

charlevoix 1

However, around 342 million years ago was a really terrible span of time to live there.

It’s hard to tell why from the ground. The road from Quebec City dipped down steeply to get to the sleepy resort town of Baie-St.-Paul, climbed up a winding local road to the village of Les Eboulements perched on a cliff, and then wound back downhill to La Malbaie further north. To get to the Quatre Vents Garden, we drove uphill again along the coast north of La Malbaie. Looking at the map, the main highway that we didn’t take sweeps around in a half-circle from St. Paul to La Malbaie following the easy route through the valley.

That’s pretty odd. The rest of the valleys in the area run roughly perpendicular to the coast. Why would a valley do a u-turn and meet the coast on both ends? (valley represented by the white line on the map below)

Charlevoix map

Well, it turns out that this particular valley had some help in the form of a 1.2 mile-wide chunk of rock.

The meteor crashed into what is now the Charlevoix in the early Carboniferous period; scientists’ current best guess is that it struck 342 million year ago with a 15-million year range of error on either side. The impact razed any flora and fauna, flattened the landscape, and created dramatic shatter cone structures in the whatever underlying Ordovician limestone it didn’t pulverize completely.

https://i2.wp.com/www.impact-structures.com/wp-content/uploads/2014/11/3.png

Image of an excavated shatter cone, courtesy of impact-structures.com

 

Initially, the crater was as bowl-shaped as anyone would intuitively expect from bedrock that had been punched by a giant boulder from outer space. Over time, however, the center of the crater rose as a reaction to the absence of pressure after the impact. That rebound created the higher elevation where Les Eboulements stands today.

Us humans have this impact to thank for the half-circle of relatively flat terrain between Baie-St.-Paul and La Malbaie, where 70% of the population of the Charlevoix region now resides.

https://i2.wp.com/www.impact-structures.com/wp-content/uploads/2014/11/radarbild-Charlevoix.jpg

The crater has a much more uniform and gentle gradient, compared to the rugged highlands of the Laurentian Highlands. A RadarSat image of the Charlevoix area, courtesy of the Canadian Space Agency via impact-stuctures.com

But where is the other half of the crater? It was no match for the seismic and glacial stresses of the past 340 million years. Pangaea crashed together 40 million years later and was torn apart 125 million years after that, and between 2.5 and 0.7 million years ago an ice cap took advantage of those faults in the crust to carve away the weak points. When that ice cap shrank, all that glacial melt poured through the St. Lawrence and washed away what was left.

Charlevoix from Quatre vents

The view looking south from Quatre Vents Garden on the northern rim of the crater, across La Malbaie in the sunken impact ring, towards the rebounded area of Les Eboulements.

I wish I had discovered Observatoire de l’Astrobleme de Charlevoix and its awesome geological app before the trip, but if I ever go back I’ll definitely get it!

Up Next: Oh, Canada! Part 3: Clay and Quakes

 

Oh, Canada! Part 1: Monadnocks

Intro: Oh, Canada!

The drive from Montreal to Quebec City looked at first to be an unremarkable straight-line drive along the marching lines of pylons carrying hydroelectric power west and long rows of pig farms. The fertile farmland along the St. Lawrence was a perfectly uniform neon green carpet only interrupted by the farmhouses and squat concrete businesses lining the highway. Then, all of a sudden, Mont Saint-Hilaire popped up on the horizon. It looked ridiculously random, like a gargantuan pine-covered bear had curled up to rest for a moment while ambling from the Adirondacks to the Laurentians. And it wasn’t alone! As we drove past Mont Saint-Hilaire we saw another huge hill towering over the flat agricultural landscape far in the distance- Mont Rougemont.

Sthilaire

This image of Mont Saint-Hilaire courtesy of the PlentyofNothing blog, as mine didn’t turn out. It looks more bear-like from ground level, I promise. http://lintel.typepad.com/plentyofnothing/2010/04/les-mont%C3%A9r%C3%A9giennes.html

These isolated hills have the fun-to-say moniker of “monadnocks”, named after the Abenaki name of the type example in New Hampshire.

Mont Saint-Hilaire, Mont-Royal in the center of Montreal, and their fellow Monteregian Hills in Quebec are actually parts of a much larger family of igneous intrusions stretching from Triassic kimberlites in Nunavut to the Miocene Great Meteor Seamount in the Northern Atlantic- all children of the Great Meteor Hot Spot. David W. Eaton & Andrew Frederiksen reconstructed a map of its path in a 2007 article published in Nature. I’ve shown a figure from it below to show the extent of the extended family of plutons, which are igneous intrusions that formed as buoyant magma rose through cooler overlying layers of rock.

It’s a diverse family. Pangaea started to break apart 200 million years ago, and the earliest of the plutons formed approximately 178 to 147 million years ago  as the magma rising off of the hot spot created the Churchill Kimberlite deposits in Nunavut and Ontario. Unlike the famous diamond-bearing kimberlites of Africa or even those further west in Canada, these kimberlite tubes ferried up spinels and olivine from deep within the mantle to the surface. Little topographic relief remains from these intrusions, as they are located under what was ground zero of the Laurentian ice sheet during the Pleistocene.

As the North American continent floated northwest during the breakup of Pangaea, the stationary hot-spot within the mantle created a south-east-trending series of volcanic necks punching up through the overlying sedimentary rock. Next up were the Monteregian hills around 129 million years ago. These hills are mainly composed of syenite, which is an alkali-rich magma with a composition similar to granite but impoverished in quartz. (citation)The cool thing about a hot spot is that the magma that forms the intrusions is influenced by the diversity of rocks that it melts through. Mont Saint-Hilaire is a mineralogist’s dream – over 277 varieties of minerals have been cracked out of the geodes of Mont-Saint-Hilaire, many new to science!

The rare mineral Serandite, found at Mont Saint-Hilaire.

(http://www.dakotamatrix.com/mineralpedia/8304/serandite)

 The sturdy igneous rocks of these monadnocks are much more resistant to weathering than the surrounding sedimentary rocks and so stand proudly above the surrounding area that has been washed away by rivers, cracked by frosts, and bulldozed by ice sheets.

As the steady expansion from the mid-Atlantic ridge North America northwest away from Europe and Africa, the hotspot came to rest under New England and form the White Mountains of New Hampshire that give monadnocks their name around 100 million years ago. After that, the hot spot ran out of North America above sea level and started to create the New England seamounts between 80 and 100 million years ago. All was quiet for a few million years while the Great Meteor hot spot took a well-deserved break from its creative streak, ducked under the mid-Atlantic ridge, and then belched out the Seewarte Seamounts on the African plate around 15 million years ago.

Despite the diversity of forms of the intrusions and the changing composition of the magmas depending on the overlying rocks within the Great Meteor Hotspot Track, studies such as Zurevinski, Heaman, and Creaser 2011 showed that the isotopic composition of strontium and neodymium in the rocks are similar enough for them to all to be driven by the same hot spot deep beneath the crust.

Hot spots are tricky beasts to study, especially when their handiwork lies too deep beneath the sea to get a rock sample to analyze for mineral similarities to suspected igneous relatives. The Hawaiian hot spot steals the spotlight, of course, since everybody loves a good explosion from a distance. There’s no proof that the Monteregian hills ever went ballistic like that, as the remaining rocks look more like volcanic necks that cooled calmly far beneath the surface. On the other hand, this slow geologic process gave us all the explosion of colorful minerals found in Mont Saint-Hilaire!

Twenty minutes passed by, and Mont Saint-Hilaire and its comrades faded into the rear-view mirror, and we reached Drummondville.From there to Quebec City the pig farms were once more the highlights out the window, with the exception of the melodramatic billboards admonishing us all to avoid the perils of texting while driving. Very Quebecois.

Up next: from the Great Meteor Hot Spot Track to the actual meteor that hit the Charlevoix! Oh, Canada! Part 2: Impact