2018/12/10

Interpreting Geology in Tennessee

I was recently asked "How does one tell the difference in the limestone without a degree in geology?" This is a wonderful question. Below I will share some of my methods, and look at how effective those methods are at understanding the landscape.

As a geographer, my go-to for most things is to look at a map. I collect data and organize it and add to and improve it over time. This gives me an advantage, but it need not be exclusively mine. First in order to explore the data, you'll need some tools. This sort of analysis is appropriate for a desktop computer or laptop, not so much a cell phone operation as most cell phones can't hold and display data necessary to convey meaningful descriptions.
Geology Panel, Fentress and Pickett Counties, Tennessee
The first tool I recommend getting is Google Earth Pro. This is free, and can be downloaded here:
https://www.google.com/earth/versions/#download-pro

Install Google Earth Pro after you have downloaded it. It will associate files with the extension .kml and .kmz to open in Google Earth Pro when you double-click on them. You'll need to find some kmls now to display in Google Earth Pro.

Go to the link below to download the Tennessee statewide geology layer. Look for the link to tngeol.kmz.
https://mrdata.usgs.gov/geology/state/state.php?state=TN

Once you've downloaded this, double click the file and it should open in Google Earth. This geologic layer was created at 1:250,000 scale, so it is only marginally accurate when you're looking closely. It is great for creating at state wide scale, but not so good at looking at things up close.

For up close features, I use geologic maps at 1:24,000 scale, which are more than 10x as accurate. This data has unfortunately not publicly available until now. I make no promises as to the quality or accuracy of this (it does have errors), and it is an incomplete layer. Click here to download Tennessee State Geology 1:24k (incomplete; 344mb).

Making the connection from understanding the geology, to interpreting the landscape and understanding where interesting landforms are at is the next leap. I picked up most of these skills listening to other cavers and walking around looking for cave entrances. Along the way I figured some patterns out in regard to the distribution of waterfalls and natural arches.

These patterns are better described in other blog posts here:
Tennessee's Eastern Highland Rim - Part 1 - Geology
Tennessee's Eastern Highland Rim - Part 2 - Geography
Tennessee's Cumberland Plateau
Fort Payne Formation & Chattanooga Shale Contact Waterfalls
KTAG - Cave Density Map

I regard the next few links as incomplete. It's part of a project I've been working on to flesh out specific strata within the Mississippian strata of the Eastern Highland Rim. Here are links to a few (partially finished) reports:
Tennessee Mississippian Strata: Pennington Formation
Tennessee Mississippian Strata - Fossils - Bangor limestone
Tennessee Mississippian Strata - Fossils - Hartselle sandstone & Monteagle limestone

If you want to get real serious into map reading and interpretation check this blog post out. It's more than geology, and requires more complicated tools to develop and interpret, but it is accessible to the public:
Lidar Map of Sparta, Tennessee

This is a lot of data. The data alone is no substitute for spending time looking at things. Take the time to match up familiar features with their specific geology. Check your hunches with more seasoned geographers, geologists, and naturalists.

2018/09/10

Cleanup and Graffiti Removal at Black Mountain

It's infuriating to any decent human that some fools find beautiful places and destroy them. Case in point, Black Mountain, a rock town in Cumberland County, and a segment of the Cumberland Trail State Park has been a location growing in popularity with these idiots.

I became aware of some black spray paint on the boulders below a few months ago and it had been sitting in my mind for some time. The amazing Chattanooga photographer, Kelli Lewis and I planned to catch sunrise there on Saturday, and it was decided that we would put some time into cleaning up and attempting to remove the vandalism there. Terri Likens, Caleb Ottinger, Brandon Mullins, and Cody Julian also joined us participating in the cleanup as well as the graffiti removal.

Upon arrival I noticed plenty of other recent graffiti in the form of blue and green spray paint. Given the vastness of the surface covered in spray paint, I decided to treat only select areas this day.

Here are the before photographs by location:

Green Paint Pen
Green paint pen, cleanup and graffiti removal Black Mountain, Cumberland Trail SP, Cumberland County, Tennessee 1

Black Spray Paint
Black spray paint, cleanup and graffiti removal Black Mountain, Cumberland Trail SP, Cumberland County, Tennessee 1

Blue Spray Paint spot 1
Blue spray paint, cleanup and graffiti removal Black Mountain, Cumberland Trail SP, Cumberland County, Tennessee 1

Blue Spray Paint spot 2
Blue spray paint, cleanup and graffiti removal Black Mountain, Cumberland Trail SP, Cumberland County, Tennessee 2

Blue Spray Paint spot 3
Blue spray paint, cleanup and graffiti removal Black Mountain, Cumberland Trail SP, Cumberland County, Tennessee 3

Blue Spray Paint spot 4 - not cleaned for safety reasons
Blue spray paint, cleanup and graffiti removal Black Mountain, Cumberland Trail SP, Cumberland County, Tennessee 4

CitriStrip was applied and left to soak for 30-40 minutes for each location. One or more people used water in a spray bottle and sponges to remove. Our results were mixed, but we believe that all the spray paint sites were at least faded by our effort. The paint pen vandalism was completely removed. Below are the after photos. We would have waited until the water dried to photograph them, but an incoming thunderstorm forced us off the mountain.

Green Paint Pen
Green paint pen, cleanup and graffiti removal Black Mountain, Cumberland Trail SP, Cumberland County, Tennessee 4

Black Spray Paint
Black spray paint, cleanup and graffiti removal Black Mountain, Cumberland Trail SP, Cumberland County, Tennessee 2

Blue Spray Paint spot 1
Blue spray paint, cleanup and graffiti removal Black Mountain, Cumberland Trail SP, Cumberland County, Tennessee 8

Blue Spray Paint spot 2
Blue spray paint, cleanup and graffiti removal Black Mountain, Cumberland Trail SP, Cumberland County, Tennessee 9

Blue Spray Paint spot 3
Blue spray paint, cleanup and graffiti removal Black Mountain, Cumberland Trail SP, Cumberland County, Tennessee 10

Much more work remains. Most people don't want to see vandalism, and it infuriates most people. If most people would act on this, then we could make short work of of the vandalism at Black Mountain and send a clear message to the people who do these things - Don't put your stupidity on display.

2018/08/20

Landslide on Gee Creek

While hiking in the South Cherokee National Forest and Wildlife Management area this weekend I observed what appeared to be a fresh landslide. I was excited at the chance to look closely at this and document a fascinating geologic event.

The location of the rockfall is at 35.246533, -84.529235, on the north side of Gee Creek right above the cement tunnel formerly used by the mill operation. The rock that dropped is Nebo Sandstone, part of the Chilhowee Group. In the photos and map below you can see the steeply dipping in-situ rock unit. 





2018/08/15

Oddities of Official Place Names of the United States

There are 2,278,005 registered place names in the United States. The average length of a place name is 19.46 characters. The average number of words in a place name is 2.89.

At 117 characters, the longest official place name of the United States is Center Street Colored Methodist Episcopal Church-Chestnut Street Colored Methodist Episcopal Church Historical Marker.

There are 25 places which have short names of only two characters: 

Ai, AL, Ai, GA, Ai, OH, Ai, MH, Ai, NC, Ex, AK, Hy, MO, Ii, PW, Iw, FM, Kì, HI, Ka, VA, Le, WY, Mo, FM, Na, FM, Ni, MH, Or, FM, Ot, FM, Ot, FM, Ow, FM, Oz, KY, Ri, FM, Ti, OK, To, FM, Uh, FM, and Yo, MH

With 19 unique words, the building San Juan County Fire District 2 / Orcas Island Fire and Rescue Station 24 Deer Harbor / Spring Point tends to stand out.


You may find it frustrating as a resident of Grant's Vacation Park Recreational Vehicle and Mobile Home Park if you are having to write your address frequently. It turns out that all 8 of the places one can live with the most words are all mobile home parks.

There are some odd stream and river names out there, including Little North Fork North Branch North Fork Elk River, or North Fork of South Fork of North Fabius River.

Data processing done with data from NationalFile_20180801.zip located at 
Domestic and Antarctic Names - State and Topical Gazetteer Download Files. Software used was Microsoft Access 2007, and ArcMap 10.6.1.

2018/08/06

Cedar Ridge Crystal Cave

This is mostly macro work that I did at Cedar Ridge Crystal Cave. I experimented with extension tubes shooting water drops at the end of soda straws. The photos aren't as crisp as I would like. Next time I will use a different lens. If anyone sees this, let me know what you think. :)

Soda straw, Cedar Ridge Crystal Cave, Marion County, Tennessee 1 [macro]
Soda straw, Cedar Ridge Crystal Cave, Marion County, Tennessee 2 [macro]
Soda straw, Cedar Ridge Crystal Cave, Marion County, Tennessee 3 [macro]
Helectite, Cedar Ridge Crystal Cave, Marion County, Tennessee 1 [macro]
Helectite, Cedar Ridge Crystal Cave, Marion County, Tennessee 2 [macro]
Helectite, Cedar Ridge Crystal Cave, Marion County, Tennessee 3 [macro]
Soda straws, helectites, Cedar Ridge Crystal Cave, Marion County, Tennessee 2 [macro]
Soda straws, helectites, Cedar Ridge Crystal Cave, Marion County, Tennessee 3 [macro]
Curtain formation, Cedar Ridge Crystal Cave, Marion County, Tennessee [macro]
Soda straws, Cedar Ridge Crystal Cave, Marion County, Tennessee 2

2018/06/12

Water Feature Names

Confluence of Caney Fork River and Big Spring (creek), Bridgestone Firestone Centennial Wilderness WMA, White County, Tennessee I was curious after a conversation with fellow geographer, David Starnes, what the frequency of descriptors (which I call classes for the purpose of this analysis) like stream, creek, branch, prong, fork, etc. are regionally. I did some analysis, and here are some tables of what I found. Details of the analysis follow the tables.



Cumberland River and Obey River confluence, Clay County, Tennessee

I very well could have called this "Hierarchical Water Feature Name Frequency using GNIS in the NHD Regions 5 and 6" but opted for a more user friendly title given my audience. For this analysis I utilized the National Hydrography Dataset (NHD) which gets names for features from the Geographic Names Information System (GNIS).

I joined NHD data to the NHD Plus data to get stream order information, which for the lay user could be considered a measure of the size of the stream. Since I was interested in changes in the descriptors of smaller water features grading upwards to larger water features, stream order was the easiest measure to work from and 
hierarchically organize the data.



I used Excel to isolate the final word in each water feature name to see only the descriptor. I counted frequency of each descriptor by stream order, as well as the length of stream miles associated with each. Both the count and length can be used to assess frequency.

Table 1 shows the number of unique descriptors associated with each stream order, as well as the mileage of each stream order in terms of total, named, and unnamed features. The class mode shows the most frequently used descriptor.

Table 2 shows the individual descriptors for each stream order and their respective frequency and length. Interesting descriptors point to unique place names such as The Slough in Meigs County, Ohio; The Thoroughfare in Pleasants County, West Virginia;
Right Fork Dixfork in Pike County, Kentucky; Upper River Deshee in Knox County, Indiana; Old Kinniconick Bed in Lewis County, Kentucky; Big Sang Kill in Mingo County, West Virginia; and Virginia Rill in Martin County, Indiana. Curious names likely have interesting stories. If you know one of them, leave me a comment!

2018/04/13

Waterfalls and Wildflowers at Standing Stone

Standing Stone map, Overton County, Tennessee
Standing Stone is an area named for the monolith that once stood in Monterey. (Sadly, little remains of the original monolith.) The area consists of a state park, state forest, and a wildlife management area.

I spent several days over the last week exploring Standing Stone trying to catch wildflowers in their prime. My timing was excellent and the showing of wildflowers was as well. After a few hours of exploration I noted that the Chattanooga shale exposed in the park often produced nice cascades and waterfalls. Unfortunately, most were ephemeral features. On a hunch I ended up walking up Bryans Creek and found the most beautiful undescribed 35' waterfall. 

Bryans Fork Falls, Standing Stone SF & WMA, Overton County, Tennessee 7 Bryans Fork Falls, Standing Stone SF & WMA, Overton County, Tennessee 6

Previous to my documentation of Bryans Creek Falls, I had bumbled around with my friends Kurt Heischmidt and Haley Dickson. We visited OV440 (a cave whose name I feel best to withhold), and a few other interesting features.

Kurt Heischmidt, Haley DIckson, Mill Creek Cave, Standing Stone State Forest & WMA, Overton County, Tennessee Unnamed cascade, Standing Stone State Forest & WMA, Overton County, Tennessee 2 Dock, Standing Stone Lake,Standing Stone State Park, Overton County, Tennessee Kurt Heischmidt, OV440, Standing Stone State Forest & WMA, Overton County, Tennessee 1 OV440, Standing Stone State Forest & WMA, Overton County, Tennessee 4 Low head dam on Bryans Fork, Standing Stone State Forest & WMA, Overton County, Tennessee 3 Grave Flower Cascade, Standing Stone State Park, Overton County, Tennessee 1 Grave Flower Cascade, Standing Stone State Park, Overton County, Tennessee 4

Then there were the wildflowers. Five species of trillium, and plenty of other flowers certainly made the trip worthwhile.

Silene virginica, Standing Stone State Park, Overton County, Tennessee 1 Phlox divaricata, Standing Stone State Park, Overton County, Tennessee Delphinium tricorne, Standing Stone State Park, Overton County, Tennessee Trillim luteum, Standing Stone State Park, Overton County, Tennessee Trillium grandiflorum, Standing Stone State Park, Overton County, Tennessee Trillium georgianum, Standing Stone State Park, Overton County, Tennessee Trillium recurvatum, Standing Stone State Park, Overton County, Tennessee Trillium erectum, Standing Stone State Park, Overton County, Tennessee

Fort Payne Formation & Chattanooga Shale Contact Waterfalls

Part of the beauty of the Eastern Highland Rim is that the morphology of landforms is largely consistent along its north-south axis. Waterfalls are especially predictable when one knows some basic geology, and can recognize the patterns.

It's hard to talk about waterfalls in Tennessee without mentioning the webpage Tennessee Landforms. Tom Dunigan has invested a lot of time in cataloging the resources of the state and making them available to outdoor enthusiasts. The existing waterfall data used in this post all originates from his webpage and my own exploration.

The map below illustrates the relationship to known waterfalls and to the contact between geologic units. Note that described waterfalls are found where streams cross the Fort Payne formation and (since there is no Chattanooga shale on this map, we'll use the next lower strata...) Leipers-Catheys limestone.

Fort Payne Formation & Chattanooga Shale Contact Waterfalls
Examples of its waterfalls on this geologic contact include Cummins, Burgess, Twin, and many of the other large waterfalls in the region. Some areas produce large, spectacular waterfalls with deep plunge pools surrounded by an amphitheater of rocks. Some of them produce gentle cascades in steep walled valleys covered in wildflowers.

The ability to recognize both the Fort Payne formation and Chattanooga shale in the field is important for me in finding waterfalls. It's also important to be able to read maps and understand the shapes, forms, and signatures of each of these rocks to investigate leads.

In the lidar map below, circled in red is an example of the signature I'm talking about. The south by southeast trending "U" shape indicates cliff lines. Where streams cross cliffs, one gets waterfalls. Knowing the general geology from being there in person tells me that it is Fort Payne formation and Chattanooga shale.



The above feature in map, presented below as it appears in real life.

Bryans Fork Falls, Standing Stone SF & WMA, Overton County, Tennessee 1

Spotting the Fort Payne formation in the field is first a matter of understanding what cherty limestone looks like. Chert has sharp edges. Because it is comprised of a lot of chert, it is not easily mechanically weathered and makes great cliffs. Fort Payne formation ranges in color from orange (gravels are often orange) to grey and one can find quartz geodes embedded in and scattered around it under cliff lines. The fossil crinoid stems are some of the largest in the region, with many as thick as a thumb. Other fossil evidence in it includes gigantic worm burrows, which appear as large linear features protruding from the bedrock. Finally, if you have a hand sample, remember that chert will scratch a knife's blade.

Flat Creek Falls, Overton Co, TN Mississippian worm burrows, Fort Payne Formation, Old Stone Fort State Park, Coffee County, Tennessee 1 Fort Payne formation outcrop, Taylor Creek, White County, Tennessee 2 Great Falls 2, Caney Fork River, Rock Island State Park, White and Warren County, Tennessee

Chattanooga shale is much easier to identify. It is a thinly laminated black shale that will easily break given any mechanical weathering. It's ability to be easily mechanically weathered makes it easy to break with your bare hands. In the photograph of Waterloo falls below, the shale on the left appears white due to a gypsym crust (also see the close up of another example of gypsum crust on Chattanooga shale). If you're using color to identify the rock, be sure to look at a fresh face, as opposed to one which has mineralization on it. Often it will create large square or rectangular blocks due to vertical fractures which run at 90 degrees to one another. This can be seen in the photo below with Toni.

Waterloo Falls, Spring Creek, Overton County, Tennessee 1 Gypsum, Pendleton Bluff, Hardscabble Hollow, Jackson Co, TN Chattanooga Shale, Flynn Lick Impact Structure, Jackson County, Tennessee 2 Chattanooga shale, Toni Sullivan, Overton County, Tennessee

Below is a rock cut on Highway 52 in Clay County which exposes the Fort Payne formation and Chattanooga shale in a nice clean exposure. In a natural setting one will not have such a good view of the rock as it will be covered in soil, vegetation, and weathered faces which alter the color of the rock.

Highway 52 rock cut, Jon Zetterberg, Clay County, Tennessee 1

Below is Twin Falls at Rock Island State Park. This is likely the largest volume waterfall in the state of Tennessee. It originates from the overflow of the Collins River on the other side of the ridge as it passes through caves formed at upper contact of the Fort Payne formation with the Warsaw limestone. It cascades down more than 100 feet down into the Calf Killer river gorge.

Twin Falls, Caney Fork River, Rock Island State Park, White County, Tennessee 1