Tag Archives: STATEMAP

Notes from the Field: Japton and Witter Quadrangles

 

Geologic mapping of the Japton and Witter 7.5-minute quadrangles was recently completed by the Arkansas Geological Survey’s STATEMAP field team. In Arkansas, the STATEMAP Program is currently focused on detailed 1:24,000-scale mapping in the Ozark Plateaus Region, located in the northern part of the state.

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Figure 1. Japton and Witter Quadrangles on the 1:500,000-scale Geologic Map of Arkansas (Haley et al., 1993)

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Geologic Map of the Japton Quadrangle, Madison County, Arkansas. Download a digital copy at:

http://www.geology.ar.gov/maps_pdf/geologic/24k_maps/Japton_24k_geologic.pdf

Geological Map of the Witter Quadrangle

Geologic Map of the Witter Quadrangle, Madison County, Arkansas.  Download a digital copy at:

http://www.geology.ar.gov/maps_pdf/geologic/24k_maps/Witter_24k_geologic.pdf

STATEMAP is a cooperative, matching-funds grant program administered by the U. S. Geological Survey. The goal of the program is to classify surface rocks into recognizable units based on a common lithology–basically, an inventory of surface materials. Also, we strive to locate and depict any structural elements that may have deformed the rocks. The rock units are classified into formations and members, and structures are described as synclines, anticlines, monoclines, and faults. During the project, a rich dataset was recorded in the field using a portable data collector/global positioning satellite receiver as well as by traditional methods. This made possible a more detailed depiction of geological and structural features and a more comprehensive description of lithology than previous studies had done. Data collection included:

  • 629 field locations recorded and described in detail
  • 3,385 photographs taken at recorded field locations
  • 72 strike and dip measurements, most depicted on the maps
  • 950 joint orientations, depicted in a rose diagram of strike frequency
  • 1 shale pit
  • 8 springs, previously undocumented
  • 108 rock samples collected and described

The new map is useful to landowners interested in developing their land for personal or commercial purposes, to scientists seeking a better understanding of landscape evolution and geologic history, and to planners responsible for resource development and mitigating environmental impacts.

Angela Chandler, Principal Investigator for the project, wrote the grant for fiscal year 2018 and we received funding adequate to produce two maps.  Two geologists, Richard Hutto and Garrett Hatzell, began their field season last July and after putting in 76 days in the field, concluded that portion of their work in February of this year. The area of investigation lies within the Interior Highlands Physiographic Region in north Arkansas, specifically the Boston Mountains Plateau portion of the Ozark Plateaus Province. Previous work by the AGS in this area had been done in preparation for the 1:500,000-scale Geologic Map of Arkansas by Haley et al. circa 1976 (see Fig. 1). That mapping project delineated five stratigraphic units in this area, but through extensive field reconnaissance, we were able to define ten units on these maps at the 1:24,000 scale. Further division is possible, but several units were considered too thin to depict on the 40-foot contours of the topographic map currently available, or too difficult to delineate by lithology alone.

Several tributaries of the White River are located on these quadrangles including Lollars Creek, Drakes Creek, and War Eagle Creek. The White River is a major water resource in Arkansas and southern Missouri, and as such we need to learn as much as we can about this important watershed. Included in the field work was hiking, wading, or swimming the entire 13-mile stretch of War Eagle Creek located within the Witter quadrangle, the 10 miles of Lollars Creek within the Japton, and many smaller drainages. The reason we concentrate our efforts on stream beds is that there, erosion has typically removed soil and loose rock leaving well-exposed outcrops of bedrock for us to study. Also, being able to see the entire stack of the rock sequence as we move up or downstream helps put each formation in context with the others. Discovering where one formation contacts another is one of the most important things we do while mapping. Because formations are laterally extensive, similar contacts can be connected into a contact line separating one formation from another. Figuring out where to draw these lines on the map is a major goal of the project.

From mid-February through the end of June, we analyzed field data, classified rock specimens, drew formation contacts and structures on the map, then handed it off to our cartography staff to digitize. Final layout and production of the maps was accomplished by the geologists, after which they were subjected to an extensive review and editing process by fellow staff.

The following images were taken during this year’s field season. Hopefully, they will provide a small glimpse into some of what we were privileged to experience in the field this year.  They are arranged in stratigraphic order from youngest to oldest:

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Alluvium in War Eagle Creek (left). Landslide on Highway 23 above Dry Fork (right).

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Ball and pillow structures in the Atoka Formation in Drakes Creek.

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Sequence of photos zooming into herringbone cross-beds in the Greenland Member of the Atoka Formation.

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Large blocks of Kessler Limestone sliding into Lollar’s Creek.

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Sequence of photos zooming into oncolitic limestone of the Kessler Member of the Bloyd Formation. The oncolite pictured far right is nucleated on a tabulate coral.

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Lycopod (tree-like plant) fossil weathering out of the Dye Shale.

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Top of the Parthenon sandstone (Bloyd Formation) in Lollar’s Creek (left). Parthenon resting on the Brentwood Limestone (Bloyd Formation) with travertine precipitating at the drip line (right).

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Siltstone unit in the upper Brentwood Limestone. Cross-bedded (left) and bioturbated (right). 

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Biohermal mounds in the Brentwood Limestone in Jackson Creek.

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Massive bluff of limey sandstone in the Prairie Grove Member of the Hale Formation.

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Sandy limestone in the Prairie Grove. Stream abrasion has revealed cross-bedding (left) and an ammonoid (right).

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Typical thin-, ripple-bedded sandstone of the Cane Hill Member of the Hale Formation (left). A basal conglomerate in the Cane Hill contains fossiliferous and oolitic limestone pebbles and fossil fragments (right).  This unit probably rests on the Mississippian-Pennsylvanian unconformity.

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The Pitkin Limestone in War Eagle Creek.

This year we will be mapping the Weathers quadrangle which is just east of the Witter, and the Delaney quadrangle which is just south of the Durham (which we mapped two years ago). The Kings River flows through Weathers, so this should be a good place to start while river levels are low (and it’s so hot!). I will update you as I can, but until then, I’ll see you in the field!

Richard Hutto

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Cannon Creek Waterfall at Parthenon/Brentwood Contact

Notes from the Field-Durham Quadrangle

 

Geologic Map of the Durham Quadrangle, Madison and Washington Counties, Arkansas

Geologic mapping of the Durham 7.5-minute quadrangle in northwest Arkansas was recently completed by the STATEMAP field team.  STATEMAP in Arkansas is currently focused on detailed 1:24,000-scale mapping in the Ozark Plateaus Region in north Arkansas.  It is accomplished through a cooperative matching-funds grant program administered by the US Geological Survey.   Field work was performed between July and February, and included hiking/wading/swimming the entire 12-mile stretch of the upper White River located on the quad.  Previous mapping delineated five stratigraphic units for the 1:500,000-scale Geologic Map of Arkansas, but at the 1:24,000 scale, we were able to draw ten. Further division is possible, but several units were considered too thin to map on the available 40-foot contour interval.

You can download your own copy of the map at this link:

http://www.geology.arkansas.gov/maps_pdf/geologic/24k_maps/Durham.pdf

 

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Generalized Stratigraphic Column of Durham Quadrangle

The Drakes Creek Fault, which runs diagonally from the southwest corner to the northeast corner, is the most striking feature on the map.  It is part of a major structural feature in northwest Arkansas, forming a lineament that can be traced at the surface for over 45 miles.  The Drakes Creek displays normal movement, is downthrown to the southeast, and offsets strata an average of 230 feet.  Associated with the fault on the northwest side is a large drag fold. There, rocks parallel to the fault are deformed such that units typically present at higher elevations away from the fault bend down to a much lower elevation next to the fault.  Erosion along this side of the fault has exposed the core of the fold along Fritts Creek, Cannon Creek, and other places.

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Detail of Cross-section of Durham Quadrangle

The Durham quad is far-removed from areas of previous STATEMAP projects in north Arkansas.  We completed work on the Mountain View 1:100,000-scale quad last year, ending on the Brownsville quad near Heber Springs.  Focus has now turned to the Fly Gap Mountain 1:100K quad as the next high-priority area.  When completed, we will have continuous 1:24K coverage for a large portion of the central Ozark Plateaus Region.  The Durham quad was an appropriate choice to begin mapping in this area due to its proximity to designated type sections for many of the formations in north Arkansas.  This facilitated easy comparisons between our field observations on Durham with the classic outcrops where these formations were first described.  Initial field investigations included locating, describing, and sampling these historic outcrops near Fayetteville. We visited many places the names from which the stratigraphic nomenclature we still employ was derived.  These places have such names as: Bloyd Mountain, Kessler Mountain, Lake Wedington, Cane Hill, Prairie Grove, Brentwood, Winslow, and Woolsey.  Having seen the stratigraphy in these areas firsthand better prepares us to track changes in lithology and sedimentation as we continue to map to the east and south of Durham in the coming years.

The following images were taken during this year’s field season and are arranged in stratigraphic order from youngest to oldest:

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Liesegang boxworks–Greenland Sandstone.  Mapped into the Atoka Formation

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Asterosoma trace fossils–Trace Creek Shale of the Atoka Formation

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Kessler Limestone just below the Morrowan/Atokan Boundary–mapped into the Dye Shale of the Bloyd Formation

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Parthenon sandstone resting on the Brentwood Limestone, both of the Bloyd Formation.  The Parthenon was also mapped into the Dye

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Mounded bioherms in the Brentwood Limestone

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Tabulate coral colony in the Brentwood Limestone

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Herringbone cross-bedding in calcareous sandstone–Prairie Grove Member of the Hale Formation

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Goniatitic Ammonoids in calcareous sandstone–Prairie Grove

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South-dipping sandstone in the White River south of the Drakes Creek Fault–Cane Hill Member of the Hale Formation

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Soft-sediment deformation–Cane Hill

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Pitkin Limestone, below the Cane Hill near West Fork—Mississippian/Pennsylvanian Boundary

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A cluster of solitary Rugose corals–Pitkin Limestone

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Wedington Sandstone of the Fayetteville Shale at West Fork

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Base of the Wedington–mapped into the upper Fayetteville Shale

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Large septarian concretion–lower Fayetteville Shale

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Pyritized Holcospermum (seed fern seed-left) and goniatitic ammonoid (right)–lower Fayetteville Shale

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Boone Formation, along the White River in the northwest corner of the Durham quadrangle

This year, we’re moving east to map the Japton and Witter quads. Wish us luck as we begin a new field season.  We’ll try to keep you apprised, so until next time, we’ll see you in the field!

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Richard Hutto and Garry Hatzell

Statemap 2015-16 Update

 

Hello all!

Well, another year, another map!  The Brownsville quad is now published (see map below), and a link to it will be posted on our website soon.  This year marks the 22nd anniversary of Statemap, aka the National Cooperative Geologic Mapping Program, in Arkansas.  Statemap is partially funded by a USGS grant, and was established to encourage the states to map their surface geology at the 1:24,000 scale.  To date, our mapping teams have completed thirty-three quadrangles in the West Gulf Coastal Plain and, with the recent publication of the Brownsville quad, forty quads in the Ozark Plateaus.

Geologic map Brownsville, AR

The geology of the area around Greers Ferry Lake has never been mapped in great detail until now.  Previous work had been to produce the 1:500,000-scale Geologic Map of Arkansas.  Because we mapped the Brownsville quad at the 1:24,000 scale, we were able to make some observations new to science.  A fault was discovered that had never been mapped previously.  We named it the Shiloh Fault for the old town, now inundated by the lake, that lies along its trace.  Meanders of the Little Red River channel approached this fault but didn’t cross it, probably due to encountering more resistant rock on the north side of the fault.  The Witts Springs Formation had not been mapped south of the Choctaw Creek Fault before, but we were able to draw in its upper contact with the Bloyd Formation along the Devil’s Fork and several other drainages.

Overturned cross beds in massive sandstone of the undifferentiated Bloyd Formation

As on other quads around Greers Ferry Lake, we continued to find terrace deposits left behind as the Little Red River carved the valley down to its present elevation.  Some of these are stranded as much as 260 feet above the current channel bottom (now located on the bottom of the lake).

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For many years now, our mapping program has focused on completing the Mountain View 1:100,000-scale quad.  This area encompasses thirty-two 1:24,000-scale quads and stretches from Richland Creek to Sylamore Creek on the north side and from the Illinois Bayou to Greers Ferry Lake on the south side.  Now that this area is finished, our Statemap Advisory Committee has decided we should jump over to northwest Arkansas to complete work on the Fly Gap Mountain quad, just west of the Mountain View quad (see map below).

STATEMAP index for blog

So for next year, the Statemap team is going to start work on the Durham quad in the northwest corner of the Fly Gap Mountain quad near Fayetteville.  We’ll have to spend a few weeks getting our feet on the ground, so to speak, because we won’t have the benefit of already mapped quads adjacent.  Fortunately, we will be very close to the type-sections for most of the formations we’ll be mapping, so hopefully, we can study the classic outcrops and trace them into our new field area without too much difficulty.

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A type-section is an area, or even just an outcrop, where a particular formation was first described.  They are named after a local geographic feature.  Formations first described in northwest Arkansas include: the Fayetteville Shale, the Pitkin Limestone, and the Hale Formation which has the Cane Hill and Prairie Grove as members.  Members are smaller, discernable units within a formation.  The type-section for the Bloyd Formation, including the Brentwood, Woolsey, Dye, and Kessler Members, and the Trace Creek, which is the basal member of the Atoka Formation (named for its type locality in Oklahoma), is on Bloyd Mountain near West Fork.

I would like to take this opportunity to thank my field partners that accompanied me this past year.

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I started the year with Ty Johnson, who has since moved into a permanent staff position at the Survey, so congratulations to him!  He was with me for just a year, but we covered a lot of ground together.  He’s now mapping the geology of the Lake Ft. Smith area with an emphasis on landslide mitigation.

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The writer and also principle investigator of the Statemap grant, Angela Chandler, went out a few weeks in the late fall before we could fill the vacancy Ty left behind.  No matter how much I learn, she always manages to teach me something new.

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We hired Garry Hatzell, a recent U of A grad, who started fieldwork in January.  He brings an enthusiastic knowledge of paleontology to the mix, and I look forward to his continued insight into the biostratigraphy of our field areas.

Without the help of these fine folks, we couldn’t have gathered the data or produced the map.  Also, I would have been stuck in the office—a torture for the unrepentant field geologist.

Wish us luck on the Durham quad!  And if you’re in northwest Arkansas during the next twelve months and happen to drive by a Jeep Cherokee with the AGS seal on it, be sure to stop and introduce yourself.

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Until then, I’ll see you on the outcrop!

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Richard Hutto

Statemap 2014-15 Update

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Hello all,

Just wanted to let you know that the Statemap 2014-15 field mapping project has resulted in the publication of three new geologic maps.  These are the Parma, Prim, and Greers Ferry quadrangles.  Reduced images are posted below.  These should be available as .pdfs on our website in the near future.  I’ll keep you posted!Parma

Parma Quadrangle

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Prim Quadrangle

Prim boulder (cannonball concretion) in Sugar Camp Creek

Greers Ferry Layout

Greers Ferry Quadrangle

Old Terrace deposit underlying Greers Ferry, AR

Also, I would like to thank the many people who helped with data collection in the field this year, without whom this project would have been impossible.

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Andy Haner                                                        Danny Rains

 

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Angela Chandler                                                                     Stefanie Domrois

 

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Doug Hanson                                  Ty Johnson

Thanks, everyone!

 

Now it’s off to the Brownsville quad for next year!

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Richard Hutto

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Hello all! Sorry I haven’t blogged in awhile. I’ve been so busy trying to complete the maps for this year by the June 30th deadline.  But, I am proud to announce that the Geologic Maps for Shirley and Fairfield Bay are now published and available on our website!  Click below to view and download the maps.

http://www.geology.ar.gov/maps_pdf/geologic/24k_maps/Shirley.pdf http://www.geology.ar.gov/maps_pdf/geologic/24k_maps/Fairfield%20Bay.pdf

The process to create these maps takes an entire year. I kept you updated each field week from July to April last year, so I thought you might be interested to know how we take the raw data we collected in the field and use it to make a map. First of all, it’s a collaborative effort.  It takes a lot of people who specialize in various disciplines working together to make this product.  Basically, drawing the map starts with the notes we took in the field.  At each point, we tried to identify the rock formation exposed there.  Sometimes this was difficult, especially in the southern portion of the Boston Mountains Plateau where we worked this year. These rocks are all so similar–mostly sandstone and shale.  Nevertheless, if you cover as much ground as we did, you begin to discern similarities in the rock types and bedding structures, and can make formation calls based on those similarities.  Many of the points are taken on what we considered to be contacts between different formations.  These points are used to hand draw contact lines on a blank topographic base map. 2014-07-11 0032014-07-11 007 These lines are continued into areas where the contacts may not be exposed, because we assume lateral continuity of these units.  Many times there are topographic breaks along these contacts which can help us draw the lines in areas of poor exposure or in areas we just didn’t get to.  Structural lines are drawn along the trace of faults or other structures at the surface in areas where we saw the hallmarks of faulting such as deformation bands and non-vertical joints.  Also, the many strike and dip measurements we took were plotted on the map and helped determine orientation of faults and other structures, such as the axis of a monocline.  Once all the lines were neatly drawn on the topo, it was scanned into the computer and georeferenced to the grid of all quads in the state.  Next, each line was painstakingly digitized in ArcView by one of our cartographers, in this case Brian Kehner.  The digitized map was then added to a layout that Danny created in Adobe Illustrator. 2014-07-11 008

The layout includes descriptions of each formation developed from our field notes and are specific to each quad.  A correlation of map units, a generalized stratigraphic column, an inset map of the locations of the field points, a symbol chart, and a rose diagram of the frequency of each joint direction are also added to the layout.  A cross-section based on formation thickness is hand drawn, digitized, and placed along the bottom of the layout. Formations are symbolized by color and an abbreviation.  Sometimes photos are added to balance the layout.  Also plotted are any quarries or pits we found or were in the economic commodities database we keep at the Survey.

2014-07-11 012 After we have a reasonably good map, it’s printed and set out for staff review.  They really let us have it, but this editing process always greatly improves the maps.  After two or three revisions, we finalize it and send it to the USGS by June 30 to fulfill the requirements of the STATEMAP grant.  Whew!  What a relief!Geologic Map of Shirley red1 Geologic Map of Fairfield Bay red This year, as in years past, I have designed a commemorative STATEMAP t-shirt.  I’m taking orders until July 25th if anyone is interested.  They are available for the cost of the shirt you choose plus the printing.  Please email me at richard.hutto@arkansas.gov for details. AGS14_shirt_front (1)AGS14_shirt_back (1) Now we get ready to head back out again to our new field area.  This year we’ll be mapping the Parma, Prim, and Greers Ferry quads.  I’m breaking in a new field partner this time out.  Andrew Haner says he’s looking forward to seeing some of the Arkansas wilderness.   I just hope the snake count is low this year.  From what I’ve see so far, the ticks seem to be at an all time high.  I’ll try to keep you posted, but will be out of the office four days a week this year.  That will leave little time for blogging.  So until my next post, I’ll see you on the outcrop! Richard Hutto

Statemap Field Blog, April 7-9, 2014

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Hello all,

Well, this is the last week of field work for the 2013-14 season.  Of course, there’s always more one would like to have a look at, but we have to stop sometime.  On Monday, we started down by the M&NA railroad bridge at Shirley.  The big fault that makes the SW/NE lineation goes through here somewhere, but it’s difficult to say where exactly.  There are lots of non-vertical joints and deformation bands in the area, which are all good fault signs, but nothing very definitive.  The area north of the bridge is about as thick as it could possibly be with greenbriers –only passable with much effort and many scratches.  We saw very thick-bedded sandstone there which we took for Witts Springs that day, but when we came back on Wednesday, we decided it may be north of the fault, and therefore would be Imo.  We have Imo across the valley, so it’s not out of the question to have it here, but it may be just a relatively thin slice.  There are many cut and fill channel beds there, some of them with very nice soft-sediment deformation at the margins.

On Tuesday we finished up some loose ends in the northwest corner of the Shirley quad.  After we climbed way down in a hollow that had an old tornado track going through it, Danny realized he had lost his camera somewhere.  We hiked back up to the Jeep to see if it was there (it wasn’t), then retraced our steps from earlier that morning.  Still nothing.  He remembered the last time he had used it was in that horrible briar patch the day before, so after we climbed out again, we headed back there.  Sure enough, in the thickest part of the patch, where he had been practically crawling to get through, a briar had reached in his carrying case and pulled it out.  It was still dangling there about a foot off the ground right on the river bank.  At least we got it back!

Deformation bands in massive sandstone near Middle Fork north of Shirley2014-04-07 017

2014-04-09 026 2014-04-09 011On Tuesday afternoon, we went down a drainage on the west side of Middle Fork looking for more signs of a fault we have traced from the Old Lexington quad.  We definitely found a lot of deformation bands in the Witts Springs massives down there and figure there might be as much as 80 feet of throw on the fault.

2014-04-08 0192014-04-08 027Wednesday was our last day in the field this year, and we spent most of our time on the Middle Fork just north of Shirley where we had left off on Monday.  Did look like the fault goes through there because we found very-thick bedded massives on the north side (Imo) and shale interbedded with very thin-bedded sandstone on the south side (Cane Hill).  Our last couple of hours we spent getting points in several road cuts in and around Shirley.  We took a final photo in front of the town sign.

2014-04-08 048 (2)2014-04-09 047This will be Danny’s last year out in the field with me, so I’d like to take this opportunity to thank him for putting up with me and the sometimes horrendous field conditions we’ve faced together the last five years.   Looks like I’ll have to break in a new field partner next year, so should be interesting.  Now comes the time of year when we have to sit in the office and draw the maps, create the layouts, and finish the database, all to be turned in to the USGS by June 30.  It seems like a long time, but we’re always editing down to the last minute.  By the time we make it back out in the field, it will be mid-July, so the ticks and snakes will be out in full force, it will be nice and hot, and all the vegetation will be full grown.  At least that gives us something to look forward to.  Until then, I’ll see you in the office.  After that, I’ll see you on the outcrop!

 

 

 

Statemap Field Blog, March 31-April 2, 2014

 

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Hello all!

Another great week in the field.  Signs of spring are everywhere, and unfortunately the field season is drawing to a close.  We skipped around all over the Fairfield Bay quad this week, still trying to trace the very thick-, massive-bedded sandstone that we’re calling the base of the Bloyd for now.  Just off the eastern edge of the Fairfield Bay quad is a locally famous outcrop of that sandstone that was supposedly visited by Hernando Desoto himself in 1542.  Whether or not that’s true, it is a very impressive bluff shelter known as the Indian Rock House.  A lot of eroded material was removed from the floor of the shelter when the adjacent Indian Hills Golf Club was built, leaving behind the fine sandstone amphitheater we see today.   One could see how this formation could later become a natural bridge if erosion continues along the joint set parallel to the bluff face.  If that interior arch were to fall out, then the remaining one would form a bridge.  This is how most of the sandstone natural bridges in Arkansas are formed.  Lots of graffiti has been scratched into the friable rock over the years, including some that may have been carved by native people.

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On Tuesday, we finished up our field work on the lake.  We still had a couple islands we needed to visit, and the entire south side of the lake is so steep that access by land would be difficult.  We were excited to find more old river terraces on the islands, including one that would have been deposited on a cut-off meander in the area of Harpers Cove.  The deposit is about 80 feet above and over a half mile north of the current river channel (before the lake was there, that is).  The high end of the range for the downcutting rate for the Colorado River in the western Grand Canyon is 16 centimeters/1000 years, and I think we can all agree that downcutting there probably exceeds that in Arkansas.  Using that rate, an estimated 152,000 years would have passed since that terrace was deposited.  That gravel has been there a long time!  Of course, cutting off the meander would have stranded that deposit at that time, but don’t forget that this stream is developed in bedrock, so meander cut-off would be a fairly infrequent event.  To get a better estimate of these events, methods such as luminescence dating are being developed to age date the sand in these stranded river terraces.  With this new technology, perhaps someday we will know when these terraces were deposited.

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On the south side of lake below Stevens Point is a good example of a modern landslide, and a bit of a cautionary tale.  Sometimes clearing trees for roads and houses can have catastrophic results.  The photo tells the story.  The major part of this landslide occurred March 28, 2005 just after a road was cleared from the house down to the lake.  Most of the material at the edge of the lake on the north side of Hunter Mountain is there as a result of old landslides, therefore any development in this area can cause it to become unstable, as evidenced here.  That’s why part of our project includes mapping areas where landslides have occurred.

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Speaking of Hunter Mountain, we ran across one of the now ubiquitous gas well pads up there, and I thought you might be interested to know the function of each piece of typical well head production equipment.  At each wellhead is a set of valves that regulate the flow of gas.  These are often controlled remotely, thus the solar panels which power the system.  The big tanks near them contain hydrogen sulfide which is introduced into the gas right away to give it a strong odor.  This odor is, of course, quite useful to determine if there are any gas leaks since natural gas is odorless.  From the wellhead, the gas flows to the separators which remove any fluids contained in the gas.  This fluid could include heavy hydrocarbons, but is mostly produced water.  These fluids are stored in large tanks which are built inside a berm.  The berm is designed to hold 1 1/2 times the capacity of one of the storage tanks in case of a spill.  The level in the tanks is also monitored remotely and emptied on a regular basis.  From here, the gas is piped to a compression station where it undergoes further treatment.   Then it is sent through a transmission line and on to your house.  It’s not pretty, but for now, we have to have it.

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Well, next week will be the last of our field season.

Until then, see you on the outcrop!