Database for the preliminary geologic map of the Mount Hood 30- by 60-minute quadrangle, northern Cascade Range, Oregon

Frequently anticipated questions:

• What does this data set describe?
  1. How should this data set be cited?
  2. What geographic area does the data set cover?
  3. What does it look like?
  4. Does the data set describe conditions during a particular time period?
  5. What is the general form of this data set?
  6. How does the data set represent geographic features?
  7. How does the data set describe geographic features?
• Who produced the data set?
  1. Who are the originators of the data set?
  2. Who also contributed to the data set?
  3. To whom should users address questions about the data?
• Why was the data set created?
• How was the data set created?
  1. From what previous works were the data drawn?
  2. How were the data generated, processed, and modified?
  3. What similar or related data should the user be aware of?
• How reliable are the data; what problems remain in the data set?
  1. How well have the observations been checked?
  2. How accurate are the geographic locations?
  3. How accurate are the heights or depths?
  4. Where are the gaps in the data? What is missing?
  5. How consistent are the relationships among the data, including topology?
• How can someone get a copy of the data set?
  1. Are there legal restrictions on access or use of the data?
  2. Who distributes the data?
  3. What's the catalog number I need to order this data set?
  4. What legal disclaimers am I supposed to read?
  5. How can I download or order the data?
• Who wrote the metadata?

What does this data set describe?

1. How should this data set be cited?
   Ma, Lina, Sherrod, David R., and Scott, William E., 2014, Database for the preliminary geologic map of the Mount Hood 30- by 60-minute quadrangle, northern Cascade Range, Oregon:.

   Online Links:

   • https://pubs.usgs.gov/ds/906/

   This is part of the following larger work.
   Sherrod, David R., and Scott, William E., 1995, Preliminary geologic map of the Mount Hood 30- by 60-minute quadrangle, northern Cascade Range, Oregon: Open-File Report 95-219, United States Geological Survey, Menlo Park.

   Online Links:

   • https://pubs.usgs.gov/of/1995/of95-219/

2. What geographic area does the data set cover?

   West_Bounding_Coordinate: -122

   East_Bounding_Coordinate: -121

   North_Bounding_Coordinate: 45.5

   South_Bounding_Coordinate: 45

3. What does it look like?

   MH_geology_plotfile.pdf (pdf)

   GIS data layers for viewing

4. Does the data set describe conditions during a particular time period?

   Beginning_Date: 1985

   Ending_Date: 1994

   Currentness_Reference:

   The information in this report is the most up-to-date available at the time of 1995 publication.

5. What is the general form of this data set?

   Geospatial_Data_Presentation_Form: vector digital data

6. How does the data set represent geographic features?
   1. How are geographic features stored in the data set?

      This is a Vector data set. It contains the following vector data types (SDTS terminology):

      • G-Polygon (954)
      • G-Polygon (8)
      • String (2509)
      • String (125)
      • String (6)

   2. What coordinate system is used to represent geographic features?

7. How does the data set describe geographic features?

   MH_Geopoly.shp

   Polygon attribute table of geologic map units (Source: MapInfo translation)

   ID

   Row number (Source: MapInfo)

   Sequential unique positive integers generated automatically

   Unit_Label

   Text string for map-unit label (derived from age and stratigraphic name), listed here with corresponding strat_code (unique integer value), stratigraphic name, and age (from metadata table 1, xls format) (Source: Authors)

   Value	Definition
   ow	ow, 1, Open water, Holocene
   g	g, 2, Glacier, Holocene and Pleistocene
   Qabl	Qabl, 252, Andesite of Boulder Lake, Pleistocene
   Qac	Qac, 302, Andesite of Cabin Creek, Pleistocene
   Qacl	Qacl, 308, Andesite west of Clear Lake, Pleistocene
   Qae	Qae, 224, Andesite of Enola Hill, Pleistocene
   Qah	Qah, 233, Andesite of Hiyu Mountain, Pleistocene
   Qahr	Qahr, 221, Andesite of Horseshoe Ridge, Pleistocene
   Qal	Qal, 31, Alluvium, Holocene and Pleistocene
   Qall	Qall, 226, Andesite of Laurance Lake, Pleistocene
   Qam	Qam, 251, Andesite of McCubbins Gulch, Pleistocene
   Qap	Qap, 222, Andesite of Perry Lake, Pleistocene
   Qas	Qas, 303, Andesite of Skyline Road, Pleistocene
   Qaw	Qaw, 306, Andesite of Wapinitia Pass, Pleistocene
   Qbaa	Qbaa, 202, Basaltic andesite of Aschoff Buttes, Pleistocene
   Qbac	Qbac, 206, Basaltic andesite of Cloud Cap, Pleistocene
   Qbac?	Qbac?, 207, Basaltic andesite of Cloud Cap, Pleistocene
   Qbal	Qbal, 203, Basaltic andesite of Lost Lake Butte, Pleistocene
   Qbap	Qbap, 205, Basaltic andesite of The Pinnacle, Pleistocene
   Qbas	Qbas, 204, Basaltic andesite of Stump Creek, Pleistocene
   Qbc	Qbc, 208, Basalt of Crutcher Bench, Pleistocene
   Qbdc	Qbdc, 209, Basaltic andesite of Devil Canyon, Pleistocene
   Qbdr	Qbdr, 241, Basaltic andesite of Dog River, Pleistocene
   Qbp	Qbp, 201, Basaltic andesite of Parkdale, Holocene
   Qbr	Qbr, 223, Basaltic andesite of Blue Ridge, Pleistocene
   Qca	Qca, 32, Colluvial and alluvial slope deposits, Holocene and Pleistocene
   Qdf	Qdf, 307, Dacite of Frog Lake Buttes, Pleistocene
   Qg	Qg, 41, Glacial deposits, Holocene and Pleistocene
   Qget	Qget, 43, Glacial deposits, till of Evans Creek age, Pleistocene
   Qgnt	Qgnt, 42, Glacial deposits, till of neoglacial age, Holocene
   Qha	Qha, 133, Pre-Polallie rocks of Mount Hood, andesite and dacite lava, Pleistocene
   Qhc	Qhc, 131, Pre-Polallie rocks of Mount Hood, pyroclastic-flow and debris-flow deposits, Pleistocene
   Qhc?	Qhc?, 132, Pre-Polallie rocks of Mount Hood, pyroclastic-flow and debris-flow deposits, Pleistocene
   Qhdl	Qhdl, 111, Debris-avalanche deposit of Ladd Creek, Holocene
   Qhoc	Qhoc, 102, Old Maid eruptive period, pyroclastic-flow and debris-flow deposits, Holocene
   Qhol	Qhol, 101, Old Maid eruptive period, lava flows, Holocene
   Qhoc	Qhpc, 122, Polallie eruptive period, pyroclastic-flow and debris-flow deposits, Pleistocene
   Qhpl	Qhpl, 121, Polallie eruptive period, lava, Pleistocene
   Qhtc	Qhtc, 108, Timberline eruptive period, pyroclastic-flow and debris-flow deposits, Holocene
   Qiba	Qiba, 62, Intrusive basalt and basaltic andesite, Pleistocene
   Qls	Qls, 34, Landslide deposits, Holocene and Pleistocene
   Qo	Qo, 44, Outwash, Pleistocene
   Qob	Qob, 304, Olivine basalt, Pleistocene
   Qoba	Qoba, 305, Older basaltic andesite, Pleistocene
   Qoe	Qoe, 45, Outwash of Evans Creek age, Pleistocene
   Qsg	Qsg, 231, Rocks of Sandy Glacier volcano, Pleistocene
   Qt	Qt, 33, Talus, Holocene and Pleistocene
   QTa	QTa, 242, Andesite, Pleistocene or Pliocene
   QTab	QTab, 243, Andesite of Badger Butte, Pleistocene or Pliocene
   QTat	QTat, 227, Andesite of Tom Dick and Harry Mountain, Pleistocene or Pliocene
   QTat?	QTat?, 228, Andesite of Tom Dick and Harry Mountain, Pleistocene or Pliocene
   QTb	QTb, 225, Basalt, Pleistocene or Pliocene(?
   QTba	QTba, 421, Basaltic andesite, Pleistocene or Pliocene(?)
   QTbg	QTbg, 256, Basaltic andesite of Grasshopper Point, Pleistocene or Pliocene
   QTbme	QTbme, 234, Basaltic andesite of Mirror Lake and Eureka Peak, Pleistocene or Pliocene
   QTs	QTs, 601, Sedimentary rocks and deposits, Pleistocene and Pliocene(?)
   QTtla2	QTtla2, 321, Volcanic rocks in Trillium Lake area, andesite, Pleistocene or Pliocene
   QTtlb	QTtlb, 322, Volcanic rocks in Trillium Lake area, basalt, Pleistocene or Pliocene
   Qv	Qv, 61, Cinder cone or small volcano, Quaternary
   Qyba	Qyba, 301, Younger basaltic andesite, Pleistocene
   Ta	Ta, 427, Andesite, Pliocene
   Taef	Taef, 482, Andesite of East Fork Hood River, Miocene
   Taft	Taft, 435, Andesite of Fifteenmile Creek, Pliocene
   Tafv	Tafv, 483, Andesite of Fivemile Butte, Miocene
   Taj	Taj, 438, Andesite of Jordan Butte, Pliocene and Miocene
   Talb	Talb, 437, Andesite of Little Badger Creek, Pliocene
   Taop	Taop, 561, Andesite of Lolo Pass, Pliocene(?) and Miocene
   Taop?	Taop?, 562, Andesite of Lolo Pass, Pliocene(?) and Miocene
   Tar	Tar, 428, Andesite of Rocky Point, Pliocene
   Tas	Tas, 593, Andesite of Salmon Butte, Miocene
   Tatc	Tatc, 547, Andesite of Tumble Creek, Pliocene
   Tazm	Tazm, 581, Andesite of Zigzag Mountain, Miocene
   Tb	Tb, 548, Basalt, Pliocene and (or) Miocene
   Tba	Tba, 426, Basaltic andesite, Pliocene
   Tbah	Tbah, 436, Basaltic andesite of Happy Ridge, Pliocene
   Tbam	Tbam, 595, Basaltic andesite of Mack Hall Creek, Miocene
   Tbao	Tbao, 423, Basaltic andesite of the Oak Grove Fork, Pliocene
   Tbas	Tbas, 439, Basaltic andesite of Sunset Spring, Miocene
   Tbbu	Tbbu, 235, Basalt of Bull Run Watershed and other ridge-capping basalt, Pliocene and Miocene(?)
   Tbg	Tbg, 422, Basalt near Ghost Creek, Pliocene or Miocene
   Tbj	Tbj, 549, Basalt of Juniper Flat, Pliocene
   Tcgn2	Tcgn2, 1003, CRBG, Grande Ronde Basalt, normal-polarity unit 2, Miocene
   Tcgr2	Tcgr2, 1004, CRBG, Grande Ronde Basalt, reversed-polarity unit 2, Miocene
   Tcwf	Tcwf, 1002, CRBG, Wanapum Basalt, Frenchman Springs Member, Miocene
   Tcwpr	Tcwpr, 1001, CRBG, Wanapum Basalt, Priest Rapids Member, Miocene
   Td	Td, 583, Dalles Formation, Miocene
   Tdb	Tdb, 425, Dacite of Beaver Butte, Pliocene
   Tdgb	Tdgb, 491, Dacite of Graveyard Butte, Pliocene(?) or Miocene
   Tdl	Tdl, 429, Dacite north of Long Ridge, Pliocene
   Tdm	Tdm, 481, Dacite of Mill Creek Buttes, Miocene
   Tdp	Tdp, 594, Dacite of Plaza Lake, Miocene
   Tfa	Tfa, 592, Fine-grained andesite, Miocene
   Tha	Tha, 424, Hornblende-bearing andesite, Pliocene
   Tia	Tia, 533, Intrusive andesite, Pliocene and Miocene
   Tiba	Tiba, 532, Intrusive basalt or basaltic andesite, Pliocene
   Tilh	Tilh, 571, Intrusive rocks of Laurel Hill, Miocene
   Tlma	Tlma, 541, Lookout Mountain volcanic sequence, andesite, Pliocene
   Tlma?	Tlma?, 542, Lookout Mountain volcanic sequence, andesite, Pliocene
   Tlmb	Tlmb, 543, Lookout Mountain volcanic sequence, basalt, Pliocene
   Tlmd	Tlmd, 544, Lookout Mountain volcanic sequence, dacite, Pliocene
   Tlmd?	Tlmd?, 545, Lookout Mountain volcanic sequence, dacite, Pliocene
   Tma	Tma, 591, Andesite of middle and late Miocene age, Miocene
   Toa	Toa, 431, Older andesite, Miocene
   Toma	Toma, 1112, Volcanic rocks of the Mutton Mountains, andesite, Miocene and Oligocene
   Tomr	Tomr, 1113, Volcanic rocks of the Mutton Mountains, rhyolite, Miocene and Oligocene
   101	Tomt, 1111, Volcanic rocks of the Mutton Mountains, tuff and tuffaceous sedimentary rocks, Miocene and Oligocene
   Tos	Tos, 604, Older sedimentary rocks, Miocene
   Tr	Tr, 449, Rhyolite, Pliocene or Miocene
   Trbg	Trbg, 546, Rocks of Barlow Ridge and Gunsight Butte, Pliocene and Miocene
   Trgd	Trgd, 442, Rhyodacite of Gordon Butte, domes and flows, Pliocene
   Trgx	Trgx, 441, Rhyodacite of Gordon Butte, tuff breccia, Pliocene
   Trh	Trh, 582, Rhododendron Formation, Miocene
   Ts	Ts, 602, Sedimentary rocks, Miocene
   Ttla1	Ttla1, 323, Volcanic rocks in Trillium Lake area, andesite, Pliocene and (or) Miocene
   Ttv	Ttv, 451, Tygh Valley Formation, Pliocene and Miocene(?)
   Ttvp	Ttvp, 452, Tygh Valley Formation, pyroclastic and sedimentary rocks, Pliocene and Miocene(?)
   Tv	Tv, 531, Cinder cone or small volcano, Tertiary
   Tvmf	Tvmf, 563, Volcaniclastic rocks of Middle Fork of Hood River, Miocene
   Tvmf?	Tvmf?, 564, Volcaniclastic rocks of Middle Fork of Hood River, Miocene
   Tvs	Tvs, 484, Volcaniclastic rocks, Miocene
   Tys	Tys, 603, Younger sedimentary rocks, Pliocene and Miocene(?)
   u	u, 2001, Unmapped, Holocene and Pleistocene

   MH_Patterns.shp

   Polygon attribute table of alteration or lithology (Source: MapInfo translation)

   ID

   Row number (Source: MapInfo)

   Sequential unique positive integers generated automatically

   Feature

   Text string describing lithologic characteristic of patterned map unit (Source: Authors)

   Value	Definition
   Propylitic alteration	Area of propylitic clay alteration (shown patterned) in west-central part of map area between Still Creek and Salmon River, as mapped by Wise (1969)
   Hanging-wall breccia	Crushed rock derived from sole of reverse or thrust fault
   Dacite scoria	Dacitic cinder conde that underlies Graveyard Butte and adjacent area
   Near-vent scoria	Near-vent deposits of Rocky Point volcano (unit Tar)
   Volcaniclastic deposits	Fragmental deposits, likely dome-collapse, within unit Tdm (dacite of Mill Creek Buttes)
   Tuff breccia (block-and-ash and lahar deposits)	Fragmental deposits within unit Trbg, found in limited outcrop area at south end of Barlow Ridge

   Unit

   Text string for map-unit symbol that underlies patterned area (Source: Authors)

   From Description of Map Units (map pamphlet)

   Pattern

   Text string describing pattern used on printed version of 1995 map publication or this version (Source: Authors)

   Value	Definition
   Hachured	Regularly patterned discrete line elements
   Stipple	Random-pattern dots
   Coarse stipple	Random-pattern and randomly sized dots

   MH_Contacts.shp

   Arc attribute table of mapped contacts (Source: MapInfo translation)

   ID

   Row number (Source: MapInfo)

   Sequential unique positive integers generated automatically

   Line_code

   Positive integer as numeric descriptor corresponding to contact characteristic (Source: Authors)

   Value	Definition
   10	Contact precisely or approximately located; boundary between adjacent stratigraphic units sufficiently close that position has been determined by field work to within 100 m on the ground (1.0 mm at 1:100,000 scale)
   11	Contact inferred, approximately located; boundary drawn arbitrarily using aerial photography to demarcate geologic or volcanic feature with confidence that position lies within 200 m on the ground (2.0 mm at 1:100,000 scale)
   12	Contact internal; separates sequentially younger deposits within Polallie eruptive episode
   13	Limit of propylitic alteration; encloses an area of propylitic clay alteration (shown patterned) in west-central part of map area between Still Creek and Salmon River, as mapped by Wise (1969)
   15	Contact figurative; boundary of areas unmapped or poorly mapped
   16	Neatline; edge of geologic unit owing to position of map neatline
   19	Contact, scratch; marks uncertain limit of tuff breccia (area shown patterned) within unit Trbg at south end of Barlow Ridge where traverses were limited
   41	Moraine crest; shows approximate location for crestlines of ridges that formed as lateral moraines, as drawn from air photos and topographic maps

   MH_structure.shp

   Arc attribute table of faults, fold axes, and lineaments (Source: MapInfo translation)

   ID

   Row number (Source: MapInfo)

   Sequential unique positive integers generated automatically

   Line_code

   Positive integer as numeric descriptor corresponding to fault characteristic (Source: Authors)

   Value	Definition
   21	Normal fault, approximately or well located; fault exposed or displaced stratigraphic units sufficiently close that position has been determined by field work to within 100 m on the ground (1.0 mm at 1:100,000 scale)
   22	Normal fault, inferred; geologic relations or ground surface morphology suggest fault present but not exposed and too uncertain to determine position closer than 100 m with confidence
   24	Normal fault, concealed; trace of fault concealed by younger stratigraphic unit; positional accuracy uncertain but within 200 m on the ground (2 mm at 1:100,000) and commonly within 100 m (1.0 mm at 1:100,000)
   25	Reverse or thrust fault
   26	Reverse or thrust fault, concealed
   28	Fault, type not reported; may be oblique, reverse, or normal
   31	Anticline, showing crestline and locally showing plunge
   32	Syncline, showing troughline
   33	Monocline lower hinge, abrupt decrease of bedding dip in downslope topographic direction
   34	Monocline upper hinge; abrupt increase of bedding dip in downslope topographic direction
   35	Lineament, as mapped from air photos; origin most likely by faulting or now-obscure ground cracks

   Struc_type

   Short word phrase summarizing structural type, with one-to-one correspondence to Line_code definitions (Source: Authors)

   Value	Definition
   text string	50 or fewer characters comprising known words

   Position

   Text string indicating positional certainty as certain, approximate, or concealed (Source: Authors)

   Value	Definition
   text string	25 or fewer characters comprising known words

   Side_down

   Abbreviation as compass quadrant directions showing structurally lower side of fault or plunge direction of anticline if known (Source: Authors)

   Value	Definition
   text string	20 or fewer characters comprising known words

   Handedness

   4 or fewer characters to indicate line-tracing rule if applicable (Source: Authors)

   Value	Definition
   RH	Line digitized to follow right-hand rule for ornamentation
   none	Structural feature is symmetrical so line convention is unimportant

   Struc_name

   Text string providing geologic-geographic name for the few structural features so classified (Source: Authors)

   Free text

   MH_dikes.shp

   Arc attribute table of vertical sheet-forming intrusive bodies (Source: MapInfo translation)

   ID

   Row number (Source: MapInfo)

   Sequential unique positive integers generated automatically

   Composition

   Text string describing chemical composition estimated from hand sample (Source: Authors)

   Value	Definition
   Basalt or basaltic andesite	Composition broadly mafic
   Andesite-dacite	Composition broadly intermediate

   Strike

   Positive integer showing bearing, 360-degree clockwise compass, north as zero, and following right-hand rule so that dip is to the right when viewed along bearing (Source: Authors)

   0-360 degrees

   Dip

   Positive integer showing dip angle from horizontal (Source: Authors)

   0-90 degrees

   MH_Strikedip.xls

   Point attribute table of locations and values of bedding orientation (Source: MapInfo translation)

   ID

   Row number (Source: MapInfo)

   Sequential unique positive integers generated automatically

   Type

   Text string describing feature (Source: Authors)

   Value	Definition
   Bedding	Strike and dip of bedding plane
   App dip	Bearing and plunge of apparent dip
   Fault plane	Strike and dip of fault plane

   Attitude

   Text string describing feature orientation relative to original horizontality (Source: Authors)

   Value	Definition
   Up	Dip measured on upright bedding or fault plane
   Horiz	Feature is horizontal, top of bed upright, dip zero
   Over	Feature is overturned

   Strike_bearing

   Integer value showing orientation, in degrees, of strike line along azimuthal trend, north = zero and dip to right (right-hand rule) or of bearing, in degrees, downplunge (Source: Authors)

   0-360 degrees

   Dip_plunge

   Integer value showing dip, in degrees or plunge (angle down from horizontal) (Source: Authors)

   0-90 degrees

   Dip_quadrant

   Alphabetical abbreviation as text string indicating compass quadrant in which dip lies (Source: Authors)

   Value	Definition
   NE	Northeast
   SE	Southeast
   SW	Southwest
   NW	Northwest
   flat	flat-lying bed, strike reported as 000

   Long_NAD83

   Decimal-degree value for longitudinal position, North American datum 1983 (Source: From map digitization)

   -121 to -122 degrees longitude

   Lat_NAD83

   Decimal-degree value for latitudinal position, North American datum 1983 (Source: From map digitization)

   45.0 to 45.5 degrees latitude

   MH_Ventsymbols.xls

   Point attribute table showing locations and names of small shield volcanoes (Source: MapInfo translation)

   ID

   Row number (Source: MapInfo)

   Sequential unique positive integers generated automatically

   Vent

   Text string describing type of vent (Source: Authors)

   Value	Definition
   shield	Summit of small shield volcano, basalt or basaltic andesite in composition
   scoria cone	Summit of scoria cone, basalt or basaltic andesite in composition, and not mapped separately (as polygon in units Qv or Tv)

   Feature

   Text string listing geographic name or lack thereof (Source: Authors)

   From topographic map sheets

   Erupted unit

   Text string for the map-label code of lava flows erupted from vent (Source: Authors)

   From Description of Map Units (map pamphlet)

   Long_NAD83

   Decimal-degree value for longitudinal position, North American datum 1983 (Source: From map digitization)

   -121 to -122 degrees longitude

   Lat_NAD83

   Decimal-degree value for latitudinal position, North American datum 1983 (Source: From map digitization)

   45 to 45.5 degrees latitude

   MH_Drillholes.xls

   Point attribute table of locations and descriptions for holes deeper than 1 km (Source: MapInfo translation)

   ID

   Row number (Source: MapInfo)

   Sequential unique positive integers generated automatically

   Drill_hole

   Text string of drillhole code name (Source: Priest and others, 1982; Hook, 1982)

   Three shown, OMF-7A, OMF-1, Pucci

   Depth_ft

   Integer value showing total depth, in feet (Source: Priest and others, 1982; Hook, 1982)

   Depths range from 4002 to 6027 ft

   Year_drilled

   Text string showing year of drilling (Source: Priest and others, 1982; Hook, 1982)

   Holes drilled 1978-1980

   Long_NAD83

   Decimal-degree value for longitudinal position, North American datum 1983 (Source: From map digitization)

   -121 to -122 degrees longitude

   Lat_NAD83

   Decimal-degree value for latitudinal position, North American datum 1983 (Source: From map digitization)

   45 to 45.5 degrees latitude

   MH_Magpolarity.xls

   Point attribute table of locations for field-based determination of rock polarity using fluxgate magnetometer (Source: MapInfo translation)

   ID

   Row number (Source: MapInfo)

   Sequential unique positive integers generated automatically

   Polarity

   Alphabetic value (N, R) showing normal- or reversed-polarity magnetization measured by fluxgate magnetometer (Source: Authors)

   N or R

Who produced the data set?

1. Who are the originators of the data set? (may include formal authors, digital compilers, and editors)
   • Lina Ma
   • David R. Sherrod
   • William E. Scott

2. Who also contributed to the data set?

   The database was assembled into GIS format, with metadata, by Lina Ma and David Sherrod in 2013 from original geologic mapping compiled by David R. Sherrod and William E. Scott (Sherrod and Scott, 1995). Acknowledgment of other data is found in the map's description of map units and explanatory pamphlet.

3. To whom should users address questions about the data?
   U.S. Geological Survey

   Attn: David R. Sherrod

   Geologist

   Cascades Volcano Observatory

   Vancouver, WA
   

   USA

   360 993 8915 (voice)

   dsherrod@usgs.gov

   Contact_Instructions: preferred contact by e-mail

Why was the data set created?

This database was constructed in order to present legacy geologic-map linework in digital format.

How was the data set created?

1. From what previous works were the data drawn?

   none (source 1 of 1)

   Ma, Lina, Sherrod, David R., and Scott, William E., 2014, Database for the preliminary geologic map of the Mount Hood 30- by 60-minute quadrangle, northern Cascade Range, Oregon: Data Series, U.S. Geological Survey, Reston, Va..

   Type_of_Source_Media: Online

   Source_Scale_Denominator: 100,000

   Source_Contribution: none

2. How were the data generated, processed, and modified?

   Date: 18-Dec-2014 (process 1 of 1)

   none

   Data sources used in this process:

   • none

3. What similar or related data should the user be aware of?

How reliable are the data; what problems remain in the data set?

1. How well have the observations been checked?

   See Entity_Attribute_Information

2. How accurate are the geographic locations?

   Well located data items are intended to have a horizontal positional accuracy better than 0.5 mm at 100,000 scale, or within plus/minus 50 meters on the ground. The position of each data item is derived from USGS 1:62,500- and 1:24,000-scale topographic maps, and therefore additional inaccuracies may also be encountered that are within National Map Accuracy Standards.

3. How accurate are the heights or depths?

   No vertical positional data recorded

4. Where are the gaps in the data? What is missing?

   The digital dataset is intended to describe completely, at reconnaissance scale, the volcanic and sedimentary products and structural features of the Mount Hood 30- by 60-minute quadrangle, northern Cascade Range of Oregon at 1:100,000 scale.

5. How consistent are the relationships among the observations, including topology?

   Polygon and arc (chain-node) topology present in native MapInfo files and export shapefiles. Other shapefiles are point or annotation; neither they nor any supplied raster images require topologic relations. Polygon shapefiles were tested topologically using Mapinfo software, with no errors found for duplicate nodes, overlaps, or gaps.

How can someone get a copy of the data set?

Are there legal restrictions on access or use of the data?

Access_Constraints: none

Use_Constraints:

Uses of this digital geologic map should not violate the spatial resolution of the data. Although the digital form of the data removes the constraint imposed by the scale of a paper map, the detail and accuracy inherent in map scale are also present in the digital data. The fact that this database was edited for a scale of 1:100,000 means that higher resolution information is not present in the dataset. Plotting at scales larger than 1:100,000 will not yield greater real detail, although it may reveal fine-scale irregularities below the intended resolution of the database. Similarly, where this database is used in combination with other data of higher resolution, the resolution of the combined output will be limited by the lower resolution of these data. Acknowlegdement of the U.S. Geological Survey would be appreciated in products derived from these data.

1. Who distributes the data set? (Distributor 1 of 1)
   U.S. Geological Survey

   Attn: USGS Information Services

   GIS Planning Program Manager

   P.O. Box 25286

   Denver, CO
   

   USA

   (303) 202-4200 (voice)

   (303) 202-4695 (FAX)

   infoservices@usgs.gov

   Hours_of_Service: 7:45 a.m. to 4:30 p.m.

2. What's the catalog number I need to order this data set?

   U.S. Geological Survey Data Series 906

3. What legal disclaimers am I supposed to read?

   This database has been approved for release and publication by the Director of the U.S. Geological Survey (USGS). Although this database has been subjected to some review and is substantially complete, the USGS reserves the right to revise the data pursuant to further analysis and review. Furthermore, it is released on condition that neither the USGS nor the United States Government may be held liable for any damages resulting from its authorized or unauthorized use. Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government.

4. How can I download or order the data?
   • Availability in digital form:

     Data format:	MapInfo native files (TAB files) in format tab (version MapInfo version 8.5) Size: 1.0
     Network links:	https://pubs.usgs.gov/ds/906/
     Media you can order:	None (Density 1 none) (format none)

     Data format:	Export-format (shp) files and related geologic-map descriptive data and files for generating plots. in format "ARCE" ARC/INFO Export format (version MapInfo version 8.5) Size: 1.8
     Network links:	https://pubs.usgs.gov/ds/906/
     Media you can order:	None (Density 1 none) (format none)

     Data format:	Images of the geologic map sheet produced using this digital database and explanatory information. in format PDF (version Adobe Acrobat 5.0) Size: 9.3
     Network links:	https://pubs.usgs.gov/ds/906/
     Media you can order:	None (Density 1 none) (format none)

     Data format:	Point-location data in format Excel spreadsheet files Size: 0.03
     Network links:	https://pubs.usgs.gov/ds/906/
     Media you can order:	None (Density 1 none) (format none)

     Data format:	Readme and metadata files and PostScript plot files in format ASCII text files Size: 0.03
     Network links:	https://pubs.usgs.gov/ds/906/
     Media you can order:	None (Density 1 none) (format none)

   • Cost to order the data: No fees for digital files

Who wrote the metadata?

Dates:

Last modified: 18-Dec-2014
Last Reviewed: 30-Sep-2014

Metadata author:

David R. Sherrod

U.S. Geological Survey Volcano Science Centers

Geologist

1300 SE Cardinal Court

Vancouver, WA

USA

(360) 993-8900 (voice)

(360) 993-8980 (FAX)

dsherrod@usgs.gov

Hours_of_Service: Typically M-F 07:00 AM - 5:00 PM PST or PDT

Contact_Instructions: Preferred contact by any method

Metadata standard:

FGDC Content Standards for Digital Geospatial Metadata (FGDC-STD-001-1998)