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Thomas A. Ryer

Publications and source records attributed to Thomas A. Ryer.

12 recordsLinked to original sources
USGS1997

Fluvial-deltaic sedimentation and stratigraphy of the ferron sandstone

East-central Utah has world-class outcrops of dominantly fluvial-deltaic Turonian to Coniacian aged strata deposited in the Cretaceous foreland basin. The Ferron Sandstone Member of the Mancos Shale records the influences of both tidal and wave energy on fluvial-dominated deltas on the western margin of the Cretaceous western interior seaway. Revisions of the stratigraphy are proposed for the Ferron Sandstone. Facies representing a variety of environments of deposition are well exposed, including delta-front, strandline, marginal marine, and coastal-plain. Some of these facies are described in detail for use in petroleum reservoir characterization and include permeability structure.

Brigham Young University Geology Studies↗
USGS1989

The effects of volcanic ash on the maceral and chemical composition of the C coal bed, Emery Coal Field, Utah

Volcanic ash which fell in the peat swamp that formed the Upper Cretaceous C coal bed (Ferron Sandstone Member of the Mancos Shale, Utah) produced semi-impermeable layers that caused the ponding of surface waters. Coal samples from directly above tonsteins (altered volcanic ash partings) are enriched in desmocollinite, telinite, and detrocollinite, as a result of poorly drained swamp conditions; coal samples from directly below tonsteins are enriched in semifusinite, inertodetrinite, and fusinite, as a result of well-drained conditions. Leaching of the volcanic ash or the incorporation of volcanic ash in peat provided a source for many elements (including Zr, Nb, Th, and Ce) that are enriched in coal samples taken from directly above and below tonsteins.

Utah↗
USGS1983

Hydrology of the Ferron Sandstone aquifer and effects of proposed surface-coal mining in Castle Valley, Utah, with a section on stratigraphy and a section on leaching of overburden

Coal in the Ferron Sandstone Member of the Mancos Shale of Cretaceous age has traditionally been mined by underground techniques in the Emery Coal Field in the southern end of Castle Valley in east-central Utah. However, approximately 99 million tons are recoverable by surface mining. Ground water in the Ferron is the sole source of supply for the town of Emery, but the aquifer is essentially untapped outside the Emery area. The Ferron Sandstone Member crops out along the eastern edge of Castle Valley and generally dips 2 ? to 10 ? to the northwest. Sandstones in the Ferron are enclosed between relatively impermeable shale in the Tununk and Blue Gate Members of the Mancos Shale. Along the outcrop, the Ferron ranges in thickness from about 80 feet in the northern part of Castle Valley to 850 feet in the southern part. The Ferron also generally thickens in the subsurface downdip from the outcrop. Records from wells and test holes indicate that the full thickness of the Ferron is saturated with water in most areas downdip from the outcrop area. Tests in the Emery area indicate that transmissivity of the Ferron sandstone aquifer ranges from about 200 to 700 feet squared per day where the Ferron is fully saturated. Aquifer transmissivity is greatest near the Paradise Valley-Joes Valley fault system where permeability has been increased by fracturing. Storage coefficient ranges from about 10 .6 to 10 -3 where the Ferron sandstone aquifer is confined and probably averages 5 x 10 -2 where it is unconfined.

Utah↗
USGS1980

Use of altered volcanic ash falls in stratigraphic studies of coal-bearing sequences: an example from the Upper Cretaceous Ferron Sandstone Member of the Mancos Shale in central Utah.

The Ferron consists of 5 delta cycles, each of which includes one coal zone which contains at least one, and usually several, laterally persistent kaolinitic claystone partings. Laboratory study of the partings demonstrates that they represent altered volcanic ash falls. These partings have proven particularly useful in reconstructing the depositional history of the C coal bed of the Emery coal field which accumulated in a basin that developed concurrently with subsidence of the delta plain during both the constructive and destructive phases of the third delta cycle.-from Authors

Geological Society of America Bulletin↗
USGS1980

Thickness change involved in the peat-to- coal transformation for a bituminous coal of Cretaceous age in central Utah

The ratio of the thicknesses of a layer of peat and the coal bed formed from that peat has been calculated for a bituminous coal bed in central Utah. The method used involves comparison of the thickness of peat eroded by a laterally migrating channel system with the thickness of coal now absent from the outcrop. The peat:coal thickness ratio calculated by this method is approximately 11:1.

Journal of Sedimentary Petrology↗
USGS1977

Geology and coal resources of the Foidel Creek EMRIA site and surrounding area, Routt County, Colorado

Terrigenous clastic sediments of the Upper Cretaceous Mesaverde Group (Campanian) in the southeastern part of the Yampa coal field in Routt County, northwestern Colorado, contain many beds of bituminous coal. Lower, middle, and upper coal groups are recognized. The middle coal group, in the lower coal-bearing member of the Williams Fork Formation, contains two thick, persistent coal beds in the Foidel Creek area. The Wadge coal bed, stratigraphically the higher of the two, reaches thicknesses of 3.7 meters, and is strippable beneath large areas on the south slope of Eckman Park. Coal resources of the Wadge bed in the Foidel Creek area--an area of 134 square kilometers, as defined in this study--are estimated to be 317 million metric tons. The Foidel Creek EMRIA reclamation study site--an area of 10.9 square kilometers--contains about 36.1 million metric tons of Wadge coal, as much as 28.1 million metric tons of which occur beneath overburden 61 meters or less in thickness. About 52 meters lower in the section, the Wolf Creek coal bed locally exceeds 6.1 meters in thickness. Coal resources of the Wolf Creek bed in the Foidel Creek area are estimated to be 434 million metric tons. The Foidel Creek EMRIA reclamation study site contains an estimated 49.7 million metric tons of Wolf Creek coal.

Open-File Report↗