BLM 2002 Quads12 (Quarter quads) vector digital data Portland, OR OR BLM This theme depicts the 1:12,000 quadrangles for Oregon and Washington as defined in North American Datum 1927 (NAD27). These quads show the approximate extent of and align with the NAD27 corner ticks as displayed on USGS Topoquads. Resource Management Planning BLM (Bureau of Land Management) As described in the process steps these data were created on a regular grid of latitude/longitude to depict the 1:12,000 quadrangles covering Oregon and Washington and the surrounding areas as defined in North American Datum 1927 (NAD27). Due to the fact the dataset was originally created in NAD27 the values of coordinates defining the corners of the quads will only be those of the definition in the original datum. Once data is projected to a different datum the values will be correctly modified mathematically to reflect the change to the new projection. These quads show the approximate extent of the USGS topographic quadrangles. Since this data is constructed from corner points with straight lines connecting the corners, it does not take into account the curve between corner points introduced by the use of the UTM projection used to produce the topoquad maps. Thus this dataset is only a depiction of the extent of the topoquad. The corners of each of these quadrangles should align with the NAD27 ticks displayed on USGS topoquads in any projection used. 2002 publication date Complete Unknown -125 -116 49 41 None Base Data Lands Quadrangles index ISO 19115 boundaries None Oregon Washington Discretionary, contains no sensitive information - generally considered releasable. None. Mary Hartel Bureau of Land Management, OR/WA State Office Chief - Branch of Geographic Sciences mailing address
P.O. Box 2965
Portland OR 97208 USA (503) 808-6131 503-808-6190 mhartel@blm.gov 8am - 5pm Arc/Info, AIX/UNIX The Ohio codes were generated based on the latitude/longitude of the SE corner of the 7.5 minute (1:24,000) polygon, while the quarter quad codes were calculated from the quarter section that the polygon represents of the 7.5 Minute quad. The qqohio was calculated by adding the Ohio code and the quarter quad (QQ) code together. The results were visually checked for accuracy. This theme was created by generating the lines at a .0625 degree interval. There are no node errors or open polygons. This theme was built with polygon topology. The original defined datum is NAD27 This theme covers all lands in Oregon and Washington as well as parts of California, Nevada, Idaho, British Columbia, Alberta and the Pacific Ocean. Unknown Unknown This coverage was generated in Arc/Info using a computer program that created the polygons at 3.75-minute intervals of latitude and longitude. Another computer program used the latitude/longitude of the SE corner of the polygons to calculate their Ohio codes and quarter quad label (QQOHIO), as well as the parsed Ohio code (OHIO), first 5 digits, and Quarter quad (QQ), last two digits, code. 200007 000000 Unknown Oregon Washington Vector G-polygon 20736 0.000000001 0.000000001 Decimal degrees North American Datum of 1983 Geodetic Reference System 80 6378137 298.257 3.75-minute Quad Polygons Polygons at intervals of 3.75 minutes of latitude and longitude BLM objectid Internal feature number. ESRI Sequential unique whole numbers that are automatically generated. ohio The USGS Ohio code for the 24k (7.5-minute) quad, with the row/column coding listed first. BLM Ohio Code for the quad, with the row/column coding listed first; for example, A244117 (in which the 44 is the latitude, 117 the longitude of the southeast corner of a one degree by one degree block; 'A' refers to the first 7.5' row and '2' refers to the second 7.5' column, as measured from the southeast corner). qq The cardinal directive portion of the 7.5 minute quad. BLM The section of the 7.5 minute quad where the quad is broken in to four equal portions. A name up to 2 characters long. A value of one of four NE, NW, SE, SW. qqohio The USGS Ohio code for the 24K (7.5 minute X 7.5 minute) quad, plus the quarter quad delineation (NE, NW, SE, SW) BLM Quarter quad code is comprised of the Ohio code and the Quarter section. Ohio Code for the quad, with the row/column coding listed first; for example, A244117NE (in which the 44 is the latitude, 117 the longitude of the southeast corner of a one degree by one degree block; 'A' refers to the first 7.5' row and '2' refers to the second 7.5' column, as measured from the southeast corner). The section of the 7.5 minute quad. Where the quad is broken in to four equal portions. A name up to 2 characters long. A value of one of four NE, NW, SE, SW. shape Feature geometry. ESRI Coordinates defining the features. There are three attributes and descriptions, for the most part two attributes that are part of one, the Ohio code of a quad and the Quarter section of the quad. The attributes Ohio code and Quarter quad are portions of the QQOHIO code attribute. The format of the quad code is translated from the format typically provided by USGS. Translation is required for use in many database programs (e.g. Informix, Oracle) because often, when dealing with a character field, the database program will not accept a numeral in the first space. Eric Hiebenthal Bureau of Land Management/Northrop Grumman Data Administration Supervisor mailing address
P.O. Box 2965
Portland OR 97208 USA 503-808-6565 503-808-6374 ehiebent@blm.gov 7:30 a.m. to 4:00 p.m. Downloadable Data No warranty is made by the Bureau of Land Management as to the accuracy, reliability, or completeness of these data for individual use or aggregate use with other data. Contact distributor. Data are only available through the Oregon/Washington State office of the Bureau of Land Management. 20030101 20080206 Stanley Frazier Bureau of Land Management, Oregon State Office State Data Administrator mailing address
P.O. Box 2965
Portland OR 97208 USA (503)808-6009 (503)808-6419 sfrazier@blm.gov FGDC Content Standards for Digital Geospatial Metadata FGDC-STD-001-1998 local time