Paper No. 7
Presentation Time: 9:00 AM-6:30 PM


TURNER, Bryan W.1, SLATT, Roger M.2 and TRÉANTON, Jessica A.1, (1)ConocoPhillips School of Geology and Geophysics, University of Oklahoma, 100 East Boyd St, Suite 710, Norman, OK 73019, (2)ConocoPhillips School of Geology & Geophysics, The University of Oklahoma, 810 Sarkeys Energy Center, 100 E. Boyd Street, Norman, OK 73019-1009,

The Woodford Shale at the Hunton Anticline Quarry (HAQ) near Davis, OK, exposes ~160 feet of the Upper, Middle, and part of the Lower Woodford Shale. The HAQ provides an opportunity to test the utility of recent advances in handheld XRF technology to develop sequence stratigraphic frameworks by comparing chemostratigraphic profiles directly to gamma ray logs obtained in the same quarry. The gamma ray profile allows a direct integration of these newly obtained chemostratigraphic profiles into previously interpreted sequence stratigraphic frameworks.

The HAQ has three areas exposing the Woodford Shale. These areas are trenched to expose fresh lithologic surfaces for sampling. The trenches are measured to determine the stratigraphic thickness and described at the cm scale. Each trench is scanned at 0.5 foot intervals using a handheld XRF to determine the elemental profiles of the Woodford Shale. At the same resolution, adjacent to the trench, a gamma ray profile is scanned using a GR scintillator. The lithologic description, gamma ray profile, and elemental profiles are then used to develop the sequence stratigraphic interpretation for this location. This interpretation is then compared to sequence stratigraphic frameworks derived through well log and core analysis.

Dilution of the Zr and Ti signals correlates to drops in continentally derived sedimentation and corresponds to an increase in the concentration of K and Al which are associated with clay mineral accumulation. All these elements are regarded as relatively immobile elements. Within this outcrop K values range between 1,800 and 20,000 ppm ± 4%, Al signals between 200 and 29,000 ppm ±20%, Zr values range between 15 and 130 ppm ±7.5%, and Ti values range between 80 and 4,500 ppm ± 7%. Analyzing these elemental signals provide proxies for sedimentation. Trends of overall increasing concentrations of Zr and Ti, coinciding with decreasing concentration of Al and K, can be interpreted as progradational. Likewise, trends of decreasing concentration of Zr and Ti and increasing concentration of Al and K can be interpreted as retrogradational. Through careful analysis, these geochemical proxies can be applied to developing sequence stratigraphic frameworks within shale units that may not experience any significant lithologic variability to the unaided eye.