None
Type
Road cut (c.2005?) approximately 1500 ft long
Features of interest
Vertical section of 60 ft (max) cut back in four terraces. General lithology mixed white chert and limestone, some mudstone. Five major exposure surfaces (hardgrounds) and several minor ones, others possibly obscured by terraces. Possible mixed limestone/chert onlap to limestone dipping surface. On south end of the site, a 10 foot thick tripolitic chert layer is exposed 50 ft below top of outcrop. Tripolite layer includes some unaltered limestone areas bounded by sharp contacts. Rare chert breccia in mudstone matrix. Apparent dip in line of outcrop 0.1-0.5 deg in direction N120E.
Lithology present
Support material available
Vertical section of 60 ft (max) cut back in four terraces. General lithology mixed white chert and limestone, some mudstone. Five major exposure surfaces (hardgrounds) and several minor ones, others possibly obscured by terraces. Possible mixed limestone/chert onlap to limestone dipping surface. On south end of the site, a 10 foot thick tripolitic chert layer is exposed 50 ft below top of outcrop. Tripolite layer includes some unaltered limestone areas bounded by sharp contacts. Rare chert breccia in mudstone matrix. Apparent dip in line of outcrop 0.1-0.5 deg in direction N120E.
Lithology present
Limestone, white chert, tripolitic chert
State/County
State/County
AR / Benton County
Access
US 49
Photos (58 iPhone, 50 high resolution nikon with scale) partial photo montage. UArk MS theses: Paul Minor (2015).
Site visit history
C. Liner 11/14/2012 (loc, 40 photos), 6/18/2013 (18 photos), 2/17/2014 (50 scale photos) |
| Possible mixed limestone/chert onlap (lower red line) to massive limestone. |
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| Basal tripolitic chert layer (below red line) exposed on south end of the outcrop. |
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