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Geologic Map of the White Hills West 7 ½' Quadrangle, Mohave County

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Geologic Map of the White Hills West 7 ½' Quadrangle, Mohave County Arizona Geological Survey DGM-97 (White Hills West) 114°30' 114°27'30" 114°25' 114°22'30" 18 18 18 18 18 18 18 19 19 19 19 19 19 Description of Map Units 0 3000 4000 5000 6000 7000 8000 9000 0000 1000 2000 3000 4000 5000 0 0 0 0 0 2 2 ' 6 6 5 9 9 3 3 4 GEOLOGIC MAP OF THE ° 5 3 Qi2 Other units Qya Qi Qi WHITE HILLS WEST 7 ½' 2 2 Qya Qya Qys Qi2 Qy2r Qya Qi2 ' Qi3 Qiy 5 Disturbed ground (Holocene) - Heavily disturbed ground due to mining, extensive excavation, 4 Qi3 Qi3 ° d Qy3 Qi3 5 construction of earth dams, and highways. Qiy Qi2 3 QUADRANGLE, Qi2 Qi3 Qiy Qi2 Qya Qi2 Qya Qya Qi3 Qys Qy3 Qi Quaternary talus and colluvium (Holocene) - Unconsolidated to weakly consolidated very poorly sorted Qi2 3 Qtc Qi3 Qya MOHAVE COUNTY, ARIZONA Qi2 Qya Qi2 Qi3 angular rock debris deposited on and at the base of bedrock slopes and mantling highly eroded Qi Qya Qi3 0 Qya 2 0 bedrock hills. 0 Qi3 Qy3r Qi2 Qy 0 0 Qya 3 0 1 1 6 Qy2r Qi2 6 9 9 3 Qi2 3 Qi2 Qi3 Arizona Geological Survey Digital Geologic Map DGM-97, version 1.0 Qi2 Qi2 Qya Qya Qi3 Qiy Holocene debris flow deposits (Holocene) - Snouts, levees, scoured debris flow channels, and debris Qi3 Qy3 Qi Qyd 2 flow-deposited fans. Qyd deposits are located on or at the base of steep bedrock slopes along the Qi4 Qiy Qi2 Xgn Scale 1:24,000 White Hills and along some channels within and near the mountain front. Unit Qyd also includes areas Qya Qya Qi2 Qi2 Qi1 of erosion (debris flow scars) on hillslopes that are spatially associated with debris flow deposits. Qi3 Qy1 Qi2 Coarse cobble and boulder lag forms linear levees parallel to steep hillslope channels or irregularly Qiy Qi2 Qi2 Qy Qya Qya 3 By shaped piles representing debris flow snouts. Older Qyd deposits are predominantly composed of Qy2r Qya darkly varnished coarse cobble to boulder lag while younger deposits are less darkly varnished to Qya Qiy Qi2 Qy2 Qya Qy3 Qi Qi2 unvarnished and retain a greater portion of finer grained (silty to pebbly) matrix. Qya 2 Charles A. Ferguson, Joseph P. Cook, and Philip A. Qy3r Qya Qiy Qy2 Qi2 Qy3r Qy3 Qy3 Qiy Qi Qi2 Qy3 Qya Qya Qi2 Qi 2 Detrital Wash deposits Qys 3 Xgn Pearthree 0 Qiy Qya 0 0 Qi2 Qi2 0 0 Qy2 Qi2 Qi3 0 0 Qiy 0 6 Qys 6 October 2012 9 Qi Qi2 9 3 Qi 3 3 Active river channel deposits (Present day) - Deposits are dominantly unconsolidated, very poorly sorted Qy4r Qiy 3 Qycr Qi2 sandy to cobbly beds exhibiting bar and swale microtopography but can range from fine silty beds to Qy2 Qy3 Qy2 Qi2 Qiy Qy3 Qi3 Qi3 coarse gravelly bars in meandering reaches based on position within the channel. Clasts are typically Qy3 Qy3 sub rounded but may be angular to sub angular. Qycr deposits are typically unvegetated and exhibit no Qiy Qi3 Qy3 Qiy soil development. Qycr deposits are entrenched from 30 cm to 2 meters or more below adjacent Qy2r Qi3 Qi2 Qi2 Qi3 d floodplain deposits depending on location, geomorphic relationship, and local channel conditions. Qi Qy2 Citation for this map: Qy r Qiy 4 Qi Qy r 4 Qi3 Qiy 3 d Detrital Wash is dry at the surface throughout much of the year and only flows in response to local or 2 Qiy Qy2 Qya Qiy Qy3 Ferguson, C.A., Cook, J.P., Pearthree, P.A., 2012, Geologic map of the White upstream rainfall. These deposits are the first to become submerged during flow events and can be Qiy Qy2 Qyc subject to deep, high velocity flow and lateral bank erosion. The distribution and extent of Qycr deposits Qya Qya Hills West 7 ½' Quadrangle, Mohave County, Arizona: Arizona Geological Qya Qya Qi3 Qi2 can vary dramatically following heavy rainstorms especially in relatively unconfined, shallow reaches of Qi3 Qya Qi2 Survey Digital Geologic Map DGM-97, version 1.0, scale 1:24,000. Qya Qi3 the channel system. Qy3r Qi3 Qi3 0 Qya 0 Qi Qy2 0 Qi 2 Qi3 0 0 3 0 9 Qya Td 9 5 Qya d 5 Research supported by the U.S. Geological Survey, National Cooperative Geologic Mapping Progr am, under 9 9 Flood channel and low terrace deposits (Historical to present day) - Deposits are found adjacent to active 3 Qy2 3 Qi3 Qya Qya Qya USGS award number G10AC00428. The views and conclusions contained in this document are those of the Qy4r Qi3 Qi3 channels in the form of lightly vegetated in-channel bars, small planar fluvial terraces within 60 cm of Qy4r Qy3 Qya Qy3 Qy Qi3 authors and should not be interpreted as necessarily representing the official policies, either expressed or river elevation, and recent erosional meanders outside the modern channel. Terrace deposits are inset 3 Qi3 Qya Qy2r Qi3 implied, of the U.S. Government. into older river alluvium and are generally narrow, rarely exceeding 100 meters across. Qy4r deposits Qya Qy2 Xgn Qi3 Qi are composed of poorly sorted unconsolidated sediments ranging from fine silts to gravel bars Qya Qiy 3 42 Qtc depending on location in the channel at the time of deposition. Well preserved bar and swale Qya Qya Tdf Qya Qi2 microtopography is common. Flotsam, flood debris wrapped around shrubs and small trees, and flow Qya Xgn patterns from the most recent flow event large enough to inundate Qy4r deposits may be present on Qya Qy3 Qtc Qy4r Qya Qi3 48 part or all of the surface. Pebbles and cobbles are sub-rounded to sub-angular and include clast Qi2 d Qya Qi3 42 lithologies not present in local piedmont fan deposits. Qy4r surfaces may become inundated under Qya Qya Qy3 Qys Qy2 moderate to extreme flow events and can be subject to deep, high velocity flow and lateral bank Qi2 Qys Qys Qtc Qtc erosion. These deposits do not exhibit soil development but may exhibit a light vegetation cover of 0 0 0 Qi3 37 0 0 Qi3 0 Introduction weeds, small shrubs, creosote, and desert broom. Striated bands of mesquite and acacia mark former 8 Qy1 Qi3 Qy3 Qtc 8 5 Qy2 5 9 9 3 Qyd 3 Detrital Wash meanders. Qya Qi3 Qy3r Qi2 Qi Qiy 4 45 The White Hills West 7½' Quadrangle encompasses part of Detrital Valley, the western flank of the White Hills, Qya Qya Qi4 Low terrace and floodplain deposits (Historical) - Terrace deposits that occupy elevations from 3 to 6 feet Qi2 Qi3 Qtc Tb Tb and small part of the Black Mountains in northwestern Arizona. This map depicts the Precambrian and Qy3r Qy3 Qya above Qycr or Qy4r deposits and are inset below the pre-incision historical floodplain. Qy3r surfaces Qy1 Qy2r Qy3 Qi1 Qya Cenozoic bedrock in the mountains and late Cenozoic surficial deposits in the valley. Production of this new are generally planar but exhibit bar and swale microtopography. No soil development is present but Qya Qi2 Qi2 Qy2 medium creosote, small shrubs, and weeds sparsely inhabit the surface. Fine grained vegetation Qy1 Qtc geologic map continues the Arizona Geological Survey mapping program in northwestern Arizona that includes Qi2 Qi2 Qy2r Qi2 mounds or small nebkhas are present beneath many of the creosote and desert broom present on the " Qtc Qy2r Qi2 the Grasshopper Junction 7½' Quadrangle (Ferguson et al., 2009), Dolan Springs 7 ½’ Quadrangle (Ferguson 0 Qy3 Qy2r surface. Sediments composing these deposits are poorly sorted silt, sand, pebbles and cobbles. 3 ' Qi3 Qi3 Qtc 2 Qiy Qyd 4 et al, 2010), Middle Water Spring Quadrangle 7 ½’ Quadrangle (Johnson et al, 2012), and several 7½' Pebbles and cobbles are well-rounded to sub-angular. Trough crossbedding, ripple marks, and stacked ° 5 Qi3 39 3 Qi3 21 channel deposits observable in modern channel walls indicate deposition in a low to moderate energy Qy3r Qy3 Qi2 Qi3 Qi4 quadrangles farther southwest in the Colorado River Valley. This mapping was done under the joint State - braided to meandering stream environment with some episodes of rapid flood erosion and depostiion. Qya Qi Qtc 38 0 3 0 0 Qi2 Qiy Qtc 0 0 0 Federal STATEMAP program, as specified in the National Geologic Mapping Act of 1992, and was jointly 7 Qya 7 5 Tb 5 9 9 Qi3 " 3 Qi3 3 Young terrace and valley floor deposits (Late Holocene to Historical) - Broadly planar surfaces that stand Qiy 0 funded by the Arizona Geological Survey and the U.S. Geological Survey under STATEMAP Program Contract Qya 3 Qi3 ' 2 Tb Qy r 2 up to 2-3 meters above modern Qycr deposits. Qy2r surfaces appear predominantly fine grained at the 4 56 ° award number G10AC00428. Mapping was compiled digitally using ESRI ArcGIS software. Qyd 5 surface due in part to windblown dust deposition but are largely composed of interfingering coarse Qi3 Qi2 3 Qiy Qi4 sandy to pebbly braided channel and fine silty to sandy river channel and floodplain deposits. Little to Qi2 Qi2 Qy3r Qys Qi2 Qi2 no soil development is evident in cross section however incipient calcium carbonate accumulation is Qya Qy2r Tb The map area is located in Detrital Valley in the Basin and Range Province of northwestern Arizona. Most of the Qy3 Qtc 30 Tb present in some pebbly beds and lenses. Creosote is the dominant vegetation over the majority of the Qya Qya Qya Qi1 White Hills West Quadrangle is underlain by late Cenozoic clastic sedimentary deposits that are very thin surface however stands of mesquite and acacia line the edges of Qy2r surfaces near Detrital Wash Qi Qy3 Qi2 2 and some smaller tributary fan channels.
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