Category Archives: New Publications

2019 STATEMAP Field Calendar now available for download

Download a commemorative 25th anniversary STATEMAP Field Calendar here:

https://www.geology.arkansas.gov/publication/other-publications/statemap-field-calendar-2019.html

We are celebrating the 25th year of detailed geologic mapping in Arkansas made possible by the passage of the National Geologic Mapping Act of 1992. It established STATEMAP which distributes funds to the states, typically geological surveys, in the form of cooperative grants which are used to partially fund various geologic mapping projects. The first grant received by the Arkansas Geological Survey, then known as the Arkansas Geological Commission, was for a proposal in fiscal year 1994.  Since that time, seventy-eight 1:24,000-scale geologic maps have been completed, with two more on the way this year.  Two maps at the 1:100,000-scale have also been published.  This marks an unprecedented commitment to gathering data about the surface of the earth in our state. Following is a factsheet summarizing the STATEMAP projects in Arkansas since 1994.

Statemap Factsheet-front-2019

Here is the law establishing STATEMAP:

National Geologic Mapping Act of 1992

PUBLIC LAW 102-285

102d Congress

signed May 18, 1992

 

An Act

To enhance geologic mapping of the United States, and for other purposes.

 

Be it enacted by the Senate and House of Representatives of the United States of America in Congress assembled,

 

43 USC section 31a. Findings and purpose

(a) Findings

 The Congress finds and declares that–

(1) during the past 2 decades, the production of geologic maps has been drastically curtailed;

(2) geologic maps are the primary data base for virtually all applied and basic earth-science applications, including–

(A) exploration for and development of mineral, energy, and water resources:

(B) screening and characterizing sites for toxic and nuclear waste disposal;

(C) land use evaluation and planning for environmental protection;

(D) earthquake hazards reduction;

(E) predicting volcanic hazards;

(F) design and construction of infrastructure requirements such as utility lifelines, transportation corridors, and surface-water impoundments;

(G) reducing losses from landslides and other ground failures;

(H) mitigating effects of coastal and stream erosion;

(I) siting of critical facilities; and

(J) basic earth-science research;

(3) Federal agencies, State and local governments, private industry, and the general public depend on the information provided by geologic maps to determine the extent of potential environmental damage before embarking on projects that could lead to preventable, costly environmental problems or litigation;

(4) the combined capabilities of State, Federal, and academic groups to provide geologic mapping are not sufficient to meet the present and future needs of the United States for national security, environmental protection, and energy self-sufficiency of the Nation;

(5) States are willing to contribute 50 percent of the funding necessary to complete the mapping of the geology within the State;

(6) the lack of proper geologic maps has led to the poor design of such structures as dams and waste-disposal facilities;

(7) geologic maps have proven indispensable in the search for needed fossil-fuel and mineral resources; and

(8) a comprehensive nationwide program of geologic mapping is required in order to systematically build the Nation’s geologic-map data base at a pace that responds to increasing demand.

 

(b) Purpose

The purpose of sections 31a to 31h of this title is to expedite the production of a geologic-map data base for the Nation, to be located within the United States Geological Survey, which can be applied to land-use management, assessment, and utilization, conservation of natural resources, groundwater management, and environmental protection.

 

section 31c. Geologic mapping program

 

(c) Program objectives

The objectives of the geologic mapping program shall include–

(1) determining the Nation’s geologic framework through systematic development of geologic maps at scales appropriate to the geologic setting and the perceived applications, such maps to be contributed to the national geologic map data base;

(2) development of a complementary national geophysical-map data base, geochemical-map data base, and a geochronologic and paleontologic data base that provide value-added descriptive and interpretive information to the geologic-map data base;

(3) application of cost-effective mapping techniques that assemble, produce, translate and disseminate geologic-map information and that render such information of greater application and benefit to the public; and

(4) development of public awareness for the role and application of geologic-map information to the resolution of national issues of land use management.

(d) Program components

(3) A State geologic mapping component, whose objective shall be determining the geologic framework of areas that the State geological surveys determine to be vital to the economic, social, or scientific welfare of individual States. Mapping priorities shall be determined by multirepresentational State panels and shall be integrated with national priorities. Federal funding for the State component shall be matched on a one-to-one basis with non-Federal funds.

Miss January

https://www.geology.arkansas.gov/publication/other-publications/statemap-field-calendar-2019.html

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:

Alluvium in War Eagle CreekDSCN1957[14]

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.

Top of the Parthenon sandstone in Lollar's CreekDSCN0491

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

New Publication: Geologic Road Guide to Highway 10

 

01-Overview

The Geologic Road Guide to Arkansas State Highway 10, a Geotour of the Southern Arkoma Basin Fold Belt and Related Ouachita Mountain Tectonic Zones by Drs. Richard Cohoon (Emeritus), Jason Patton (Associate), and Victor Vere (Emeritus), Professors of Geology at Arkansas Tech University, is now available for download on the Arkansas Geological Survey’s website.  Here’s the link:

http://www.geology.ar.gov/roadside_geology_series/rgs02.htm

The route begins at Petit Roche Plaza in the River Market District of downtown Little Rock. “Petit Roche” was the name given to the first rock outcrop early explorers encountered on their way up the Arkansas River.  It is near this outcrop that the eastern end of Arkansas State Highway 10 (AR-10) is now located.  From here, you will tour the 139-mile length of AR-10 to its western terminus at the Oklahoma state line, just past Hackett.  This route traverses a beautiful and geologically diverse cross section through the mountains of western Arkansas.  The stretch from Ola to Hackett is designated as an Arkansas Scenic Byway.

An overview of the physiography of Arkansas, the concept of geologic time, and the rock formations and structural regions encountered along AR-10 introduce the reader to the detailed Road Guides that follow.  The Road Guides describe the rock outcrops and geologic features along particular sections of the route.  They contain many wonderful color photographs and color-coded geologic maps to help travelers understand the landscape passing outside their windows.  Travelers are encouraged to get out of their vehicle at several places to have a look at the rocks, perhaps gaining a new appreciation of their significance.  An illustrated glossary defines words and concepts that may be unfamiliar to those without an earth science background.  Appendices direct the traveler to several interesting side trips just off the main route and detail the characteristics of the gas and coal resources in the Arkoma Basin.

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This Geotour is written to be of interest to the general public, to students of geology, and to professional geologists who want to gain a more in-depth understanding of this beautiful and geologically complex region.  So the next time you’re thinking of taking a scenic drive through the mountains of western Arkansas, consider traveling AR-10.  And don’t forget to take along the Geologic Road Guide to make your drive more enjoyable and informative.

Richard Hutto