GSA Annual Meeting in Phoenix, Arizona, USA - 2019

Paper No. 179-5
Presentation Time: 9:15 AM


YUNG, Cathleen, Bureau of Land Management, Malheur Field Office, Vale, OR 97918

The Geological Society of America’s Geocorps program places students within federal

agencies to assist in ongoing land management operations. The Vale, Oregon district of the

Bureau of Land Management is responsible for the safe management of a plethora of diverse

geological resources. The Rhinehart Butte Community Pit of Malheur County, Oregon is a

source of decorative, silicified sandstone, but has suffered significant damage due to unsafe and

poorly regulated mining practices. In order to produce an updated mining plan that accounts for

the safety hazards present, the minable layer was mapped where exposed & cross sections were

produced to determine its extent within the federally appropriated boundary. The minable layer

proved challenging to map due to a lack of clear, planar bedding surfaces. Fortunately, a

conglomerate lens is uniformly present near the top of the sandstone layer, this feature was used

as a proxy for the true bedding plane. The average strike of this lens was found to be 170°,

dipping 12.5° E. Cross sections and modeling predicted the layer would outcrop Southeast of the

mine location. Further field visits confirmed this. Subsequently, a new mining plan was

developed to mitigate the dangers presented by the unstable high wall of the original pit mine.

The results of this project emphasise the important role basic geology plays in protecting our

natural resources from undue degradation & allowing for their safe extraction. Providing a mine

plan for the Rhinehart Butte community pit mine allows the community to continue to safely

extract resources from federal land. Mitigating safety risks also reduces liability to the Bureau of

Land Management. Placing students in government roles encourages professional development,

allows for constructive application of academic learning, and ultimately works to strengthen the

regulatory agencies tasked with the responsible use and care of our natural resources.