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G. R. Byerly

Publications and source records attributed to G. R. Byerly.

9 recordsLinked to original sources
USGS2006

Database for the geologic map of the Chelan 30-minute by 60-minute quadrangle, Washington (I-1661)

This digital map database has been prepared by R. W. Tabor from the published Geologic map of the Chelan 30-Minute Quadrangle, Washington. Together with the accompanying text files as PDF, it provides information on the geologic structure and stratigraphy of the area covered. The database delineates map units that are identified by general age and lithology following the stratigraphic nomenclature of the U.S. Geological Survey. The authors mapped most of the bedrock geology at 1:100,000 scale, but compiled Quaternary units at 1:24,000 scale. The Quaternary contacts and structural data have been much simplified for the 1:100,000-scale map and database. The spatial resolution (scale) of the database is 1:100,000 or smaller. This database depicts the distribution of geologic materials and structures at a regional (1:100,000) scale. The report is intended to provide geologic information for the regional study of materials properties, earthquake shaking, landslide potential, mineral hazards, seismic velocity, and earthquake faults. In addition, the report contains information and interpretations about the regional geologic history and framework. However, the regional scale of this report does not provide sufficient detail for site development purposes.

Washington↗
USGS2005

Geologic map of the Wenatchee 1:100,000 quadrangle, central Washington: A digital database

This digital map database has been prepared by R.W. Tabor from the published Geologic map of the Wenatchee 1:100,000 Quadrangle, Central Washington. Together with the accompanying text files as PDF, it provides information on the geologic structure and stratigraphy of the area covered. The database delineates map units that are identified by general age and lithology following the stratigraphic nomenclature of the U.S. Geological Survey. The authors mapped most of the bedrock geology at 1:100,000 scale, but compiled Quaternary units at 1:24,000 scale. The Quaternary contacts and structural data have been much simplified for the 1:100,000-scale map and database. The spatial resolution (scale) of the database is 1:100,000 or smaller. This database depicts the distribution of geologic materials and structures at a regional (1:100,000) scale. The report is intended to provide geologic information for the regional study of materials properties, earthquake shaking, landslide potential, mineral hazards, seismic velocity, and earthquake faults. In addition, the report contains information and interpretations about the regional geologic history and framework. However, the regional scale of this report does not provide sufficient detail for site development purposes.

Washington↗
USGS1987

Geologic map of the Chelan 30-minute by 60-minute quadrangle, Washington

Summary -- The Chelan quadrangle hosts a wide variety of rocks and deposits and display a long geologic history ranging from possible Precambrian to Recent. Two major structures, the Leavenworth and Entiat faults divide cross the quadrangle from southeast to northwest and bound the Chiwaukum 'graben', a structural low preserving Tertiary sedimentary rocks between blocks of older, metamorphic and igneous rocks. Pre-Tertiary metamorphic rocks in the quadrangle are subdivided into five major tectonostratigraphic terranes: (1) the Ingalls terrane, equivalent to the Jurassic Ingalls Tectonic Complex of probable mantle and deep oceanic rocks origin, (2) the Nason terrane, composed of the Chiwaukum Schist and related gneiss, (3) the Swakane terrane, made up entirely of the Swakane Biotite Gneiss, a metamorphosed, possibly Precambrian, sedimentary and/or volcanic rock, (4) the Mad River terrane composed mostly of the rocks of the Napeequa River area (Napeequa Schist), a unit of oceanic protolith now considered part of the Chelan Mountains terrane (the Mad River terrane has been abandoned, 2001), and (5) the Chelan Mountains terrane, dominated by the Chelan Complex of Hopson and Mattinson (1971) which is composed of migmatite and gneissic to tonalite of deep-seated igneous and metamorphic origin.During an episode of Late Cretaceous regional metamorphism, all the terranes were intruded by deepseated tonalite to granodiorite plutons, including the Mount Stuart batholith, Ten Peak and Dirty Face plutons, and the Entiat pluton and massive granitoid rocks of the Chelan Complex. The Duncan Hill pluton intruded rocks of the Chelan Mountains terrane in the Middle Eocene. At about the same time fluvial arkosic sediment of the Chumstick Formation was deposited in a depression. The outpouring of basalt lavas to the southeast of the quadrangle during the Miocene built up the Columbia River Basalt Group. These now slightly warped lavas lapped onto the uplifted older rocks. Deformation, uplift, and erosion recorded in the rocks and deposits of the quadrangle continued into post-Miocene time. Quaternary deposits reflect advances of glaciers down the major valleys, a complicated history of catastrophic glacial floods down the Columbia River, the formation of lakes in the Columbia and Wenatchee river valleys by landslides and flood backwaters, and hillslope erosion by large and small landslides and debris flows.

IMAP↗
USGS1986

Regional correlation of Grande Ronde basalt flows, Columbia River basalt group, Washington, Oregon, and Idaho (USA)

The tholeiitic flood basalts of the Columbia River Basalt Group of middle and late Miocene age cover more than 200,000 km 2 in Washington, Oregon, and Idaho. The most voluminous formation of the Group, the Grande Ronde Basalt, erupted for 2 m.y. from north-northwest-trending fissure systems concentrated in southeast Washington and adjacent Oregon and Idaho. Four magnetostratigraphic units (designated R 1 , N 1 , R 2 , and N 2 from oldest to youngest) are recognized on the basis of polarity in the Grande Ronde and provide the broad stratigraphic framework for the formation. In this study, major-element chemistry and relative stratigraphic position within the polarity intervals are used to identify and correlate individual flows and sequences of flows within the Grande Ronde Basalt on a regional scale. Systematic examination of more than 350 analyses from 47 stratigraphic sections show that most flows fall into one of five major chemical groupings, which are distinguished primarily by small but significant variations in MgO, TiO 2 , and P 2 O 5 content. In addition, four minor chemical types local to the eastern part of the province have been identified. Feeder dikes of each chemical type have also been located. Flows or packets of flows of each chemical type can be correlated between field sections to define specific chemical-stratigraphic subunits. These subunits consist of several flows collectively 30–150 m thick. Subunits of most chemical types are repeated at irregular intervals throughout the formation; no progressive chemical trend occurs within the Grande Ronde. Many of the chemical-stratigraphic subunits extend to the margins of the province, although most are confined to the source region in eastern Washington. Although the total number of subunits is less in the west away from the fissure systems, the total thicknesses of the N 2 and R 2 magnetostratigraphic units are each as thick or thicker than the corresponding units in eastern Washington. The greatest thicknesses occur in the central part of the province within the Pasco basin. The distribution of basalt relative to the location of vents, as well as the relative east-west thicknesses, suggests that basalt flowed hundreds of kilometres westward during the most voluminous Grande Ronde eruptions, ponding against the irregular margin of the Cascade Range and being diverted through the ancestral Columbia Gorge toward the Washington-Oregon coast. Between these huge sheetflood events, smaller eruptions blanketed areas within the source region, and ongoing regional subsidence created a shallow westward-draining basin in the center of the province.

Idaho, Oregon, Washington↗
USGS1982

Geologic map of the Wenatchee 1:100,000 Quadrangle, central Washington

The rocks and deposits within the Wenatchee quadrangle can be grouped into six generalized units: (1) Precambrian(?) Swakane Biotite Gneiss in the northeastern part of the quadrangle and the probable Jurassic low-grade metamorphic suite, mostly composed of the Easton Schist, in the southwestern part; (2) the Mesozoic Ingalls Tectonic Complex; (3) the Mesozoic Mount Stuart batholith; (4) lower and middle Tertiary nonmarine sedimentary and volcanic rocks; (5) Miocene basalt flows and interbedded epiclastic rocks constituting part of the Columbia River Basalt Group and interbedded silicic volcaniclastic rocks of the Ellensburg Formation; and (6) Pliocene to Holocene alluvium, glacial, flood, and mass-wastage deposits.

IMAP↗