Describes the surface and near outcrop subsurface extent of the coal beds within the Fruitland Formation in the northern San Juan Basin, La Plata County. Digital PDF download. OF-00-18D
From the report Abstract:
In addition to well-documented historical accounts of surface methane leaks, data on the Southern Ute Indian Tribe (SUIT) reservation appeared to link increased methane seeps at the outcrop to the dewatering of coalbed methane (CBM) wells drilled less than one mile downdip. In addition to well-documented historical accounts of surface methane leaks, there are recent data on the Southern Ute Indian Tribe (SUIT) reservation that appear to link increased methane seeps at the outcrop to the dewatering of coalbed methane (CBM) wells drilled less than one mile downdip. CBM wells have not been drilled that close to the outcrop north of the SUIT reservation, thereby providing an opportunity to compare baseline data related to coal continuity and possible methane migration pathways with data on the reservation.
In response to the task of collecting these data, the Colorado Oil and Gas Conservation Commission (COGCC) secured Severance Tax Funding for a series of scientific studies known collectively as the 3M Project (Mapping, Modeling, and Monitoring). The Colorado Geological Survey (CGS) was asked to provide the basic mapping components in the form of a geological map of the Fruitland Formation coals as well as subsurface well log cross sections from the outcrop to the Colorado-New Mexico border.
A 1:16,000 geologic map was produced along the Fruitland Formation and Pictured Cliffs Sandstone outcrop. It shows the surface extent of the various Fruitland coal beds from the north end of the Southern Ute Indian Reservation at Ridges Basin to the Archuleta County line, a distance of approximately 26 miles. The stratigraphic relationship and lateral continuity of these coalbeds is demonstrated, as are areas of major seeps, distressed vegetation, clinker, springs, coal mines, and high soil gas readings.