Kurt FriehaufPhotos from Field Geology

Kurt Friehauf

Field Geology is a course where we develop geology skills ... in the field!
We meet during the regular school week, as well as weekends.
Weekend field trips are necessary because we need full days of time for travel to field project sites and in-depth projects.
Here are a few photos from some of our field excursions.  (I only have photos from a few of our excursions because we're usually working hard!)

Adirondacks 2009

Adirondacks - stromatoliteBillion-year old algal mats called stromatolites preserved in marble - cross section view.   The rock was overturned during the mountain-forming event (orogenesis) so the fossil pictured here is upside down.
One of the things we learn in Field Geology is how to "read" rocks to determine their original orientations, as well as the geological environment that formed them. 

Adrirondacks stromatoliteTop view of a stromatolite in Adirondack marble.  The preservation of this specimen is truly remarkable!

Centralia, Pennsylvania

Friehauf - Centralia, PACentralia is a remarkable place where a fire - reportedly in an old trash pit - ignited a coal bed.  The coal bed began burning underground, generating heat and smoke.  Groundwater that seeps into the soil also heats up to form steam. 

Friehauf - Centralia, PAThe logs on the surface near the fire are charred.  Temperatures and concentrations of CO2 in the soil can be quite high, locally inhibiting plant growth.

Friehauf - Centralia, PASmoke and steam escaping the burning coal seam from a vent.

Friehauf - Centralia, PAClose-up of smoke/steam vent.

Whaleback, Pennsylvania

Friehauf - Whaleback, PAThe Bear Valley Coal Mine (a.k.a. the Whaleback) is a famous abandoned strip mine where coal miners removed all the surface rock and coal right down to the underlying shale. 

Friehauf - Whaleback, PAThe mine provides a spectacular exposure of folded rocks.  The fold in the foreground is called an anticline because it crests in the middle with the limbs of the folds dipping down into the ground away from the center.
The fold in the background is called a syncline because the fold limbs dip inwardly toward the center in a valley-shaped pattern.  Recognizing the different types of folds is an important skill for geologists because rock orientation plays a big role in slope stability, oil can be found under certain types of folds but not others, and the orientation and type of folds tell us about the mountain-forming stresses.

Friehauf - Whaleback, PAView looking right down the axis of a syncline.

Friehauf - Whaleback, PALunchtime is a time to refuel, as well as discuss geologic hypotheses and just appreciate the beauty of nature around us. 

Friehauf - Whaleback, PAMax pointing out a large fossil tree truck in the shale. 

Friehauf - Whaleback, PAMeasuring the orientation of rocks in the field is done with a Brunton compass.  The mine has some great surfaces for practicing proper procedure. 

Friehauf - Whaleback, PAHarley and Shane point out plant fossils in the shale.  The coal was made by compression of thick accumulations of plants like this.

Friehauf - Whaleback, PAMapping into the cool, shady late afternoon, students measure the orientation of rock strata pockmarked by large iron concretions (the big bulbous knobs in this photo).

Friehauf - Whaleback, PAClose-up of iron concretions in shale.

Friehauf - Whaleback, PAGood geologists record their data on their maps in the field, not back in the office.  Harley demonstrates good technique here.

New Jersey Highlands

Friehauf - New Jersey HighlandsThe contact between billion-year-old rocks on the left and overlying 500 million year old limestones on the right.  Geologic contacts between rocks of greatly different ages like this are called unconformities.

Friehauf - New Jersey HighlandsLarge stromatolites exposed in a limestone knob exposed and polished by glaciers during the last ice age. 

Friehauf - New Jersey HighlandsThe class posing with beautiful stromatolites. 

Friehauf - New Jersey HighlandsClose-up of dessication cracks in mud between stromatolite mounds.  This demonstrates the carbonate mud was periodically exposed to the air, drying the mud. 

Friehauf - New Jersey HighlandsAnother close-up of desiccated mud between stromatolite algal bodies.

Friehauf - New Jersey HighlandsGlacial striations are scratches made by the ice as the glacier flowed over the rock surface.  The red pen highlights the direction of ice flow over the limestone. 

Friehauf - New Jersey HighlandsStromatolites, dessication cracks, and glacial striations - all in one photo!

Friehauf - New Jersey HighlandsWhen a rock fractures and the two blocks of rock slide past one another, the fracture is called a fault.  During fault slippage, minerals can grow in an orientation that tells us the direction of slippage.  The mineral growths are called slickenlines.  These slickenlines are made of the mineral calcite. 

Friehauf - New Jersey HighlandsLimestone fragments in a fine, sandy carbonate mud matrix tells of an ancient storm that agitated the ocean waves enough to stir up the ocean floor, mixing mud/rock fragments with sandy mud. 

Friehauf - New Jersey HighlandsGlacial striations and rip-up clasts

Friehauf - New Jersey HighlandsThese tiny, round, concentric grains of calcite in the limestone are called ooids.  They form when waves and ocean currents along marine coasts agitate sand grains while calcium-rich waters deposit calcite on the rolling grains.  This happens today in the Bahamas.  I wonder how much New Jersey resembled the Bahamas many millions of years ago.

Sterling Hill Zinc Mine, New Jersey

Friehauf - Sterling Hill Zinc MineDr. Earl Verbeek supervises students exploring the Sterling Hill Zinc Mine.

Friehauf - Sterling Hill Zinc MineKutztown University geology students making a map of the rocks in the Sterling Hill Zinc Mine.

Friehauf - Sterling Hill Zinc MineConnor standing as scale by some very high grade zinc ore.  Black mineral = franklinite, white mineral = calcite, red = zincite, brown = willemite. 

Friehauf - Sterling Hill Zinc MineKelly carefully examining the mineralogy of the zinc ore bands.  She'll record her observations on the geologic map she is making (in her left hand). 

Friehauf - Sterling Hill Zinc MineLauren recording observations on her geologic map.  Good job, Lauren!

Monitoring groundwater

Friehauf - monitoring groundwaterMeasuring the depth to the water table in a groundwater monitoring well with an electronic tape.  The tape has wires running up/down the sides connected to a battery and a beeper.  When the tip of the tape touches water, the circuit closes and the beeper beeps telling the geologist they've reached the water table. 

Friehauf - monitoring groundwaterTheresa recording the depth to the water table.  Subtracting this depth from the elevation of the well collar tells us the elevation of the water table.  Determining the elevation of the water table at many places helps us determine the direction of groundwater flow.

Friehauf - monitoring groundwaterWorking together as a team is important for geologists.  Kutztown University geology students are very impressive in this regard. 

Other Excursions

We went on a bunch of other field excursions and will go on many more.  I'll post more photos as we do.  :-)

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