GWSL3PY metadata
Metadata Entry Template
Version 1.0.4 - July 1, 1997
A State Version of the FGDC Content Standards for Geospatial Metadata
***
Description of data created for
The Stearns County Geologic Atlas
by
DNR Waters, Groundwater Mapping Unit
Data Set Name: GWSL3PY
Metadata Entered By: Randy McGregor
Date: 8/18/99
Section 1 | Identification Information | |
Originator | Hua Zhang, DNR Waters | |
Title | GWSL3PY | |
Minnesota Clearinghouse ID | ||
Abstract | Sensitivity to pollution of groundwater | |
Purpose | County Geologic Atlas Program: Atlas C-10 Part B, Plate 10, Sensitivity of Ground Water Systems to Pollution | |
Time Period of Content Date | 1997 - 1999 | |
Currentness Reference | Complete | |
Progress | Complete | |
Maintenance and Update Frequency | None planned | |
Spatial Extent of Data | Stearns County, Minnesota | |
West Bounding Coordinate | 333,072 | |
East Bounding Coordinate | 418,103 | |
North Bounding Coordinate | 5,071,100 | |
South Bounding Coordinate | 5,015,216 | |
Place Keywords | Stearns County, Minnesota, Midwestern United States | |
Theme Keywords | Ground Water, Pollution Sensitivity | |
Theme Keyword Thesaurus | ||
Access Constraints | ||
Use Constraints | Users may wish to verify critical information; sources include both the references here and information on file in the offices of the Minnesota Geological Survey and the Department of Natural Resources. Every effort has been made to ensure the interpretation shown conforms to sound geologic and cartographic principles. This map should not be used to establish legal title, boundaries, or locations of improvements. | |
Contact Person | See METADATA CONTACT PERSON (below) | |
Contact Organization | " | |
Contact Person Position | " | |
Contact Address | " | |
Contact City | " | |
Contact State or Province | " | |
Contact Postal Code | " | |
Contact Voice Phone | " | |
Contact Fax Phone | " | |
Contact E-mail Address | " | |
Browse Graphic File Name | ||
Browse Graphic File Description | ||
Associated Data Sets | County Geologic Atlas Program: C-10 Part A, Produced by the Minnesota Geologic Survey |
Section 2 | Data Quality Information |
Attribute Accuracy | |
Logical Consistency | Data are topologically correct using ARC/INFO 7.1.1 |
Completeness | Complete |
Horizontal Positional Accuracy | N.A. |
Vertical Positional Accuracy | N.A. |
Lineage | Four coverages - 1) depth to water table, 2) subsurface permeability, 3) outline of till areas, and 4) surficial geology from MGS - were combined, using the ARC command, 'union.' DESCRIPTION OF EACH LAYER Depth to Water Table
A 1:100,000 scale manuscript showing selected CWI points colored according to 'score' value ranges was prepared in ARCVIEW and plotted on paper. 'Score' values are numbers indicating the estimated thickness of the subsurface impermeable layer. These cumulative scores were calculated by Hua Zhang from CWI Well Log data of about 4100 wells in Stearns County. Each well log was examined by a computer program written by Hua Zhang that assigned a permeability unit score based on the thickness and types of geologic materials in the upper 50 feet. The unit scores range from 0 to 1, with 0 indicating highest permeability (i.e, gravel or sand)., and 1 lowest (i.e., clay or shale). Then, a cumulative score was calculated by summation of the unit scores of all individual layers within 50 feet of the land surface. The calculated cumulative score ranges from 0 to 50. A well with clay material in the whole upper 50 feet, for example has a cumulative score of 50. A well with gravel or sand in the whole upper 50 feet has a cumulative score of 0. The cumulative scores of all wells were plotted on paper at a scale of 1:100,000. Hua Zhang drew contour lines around groups of points having:
Outline of till areas This coverage was made in order to create a geographic area of till so that peat over till could be differentiated from peat that is NOT over till. It was derived from the MGS surficial geology coverage. Map units 'dc' 'P' 'st' 'stp' 'stt' 'dsc' 'dst' 'drt' 'dlt' 'thd' 'dt' 'wt' (till areas) were selected and put (ARCEDIT command 'put') into a new coverage. A dissolve was performed to eliminate all interior lines, resulting in a coverage that shows an outline of till areas, rather than each till polygon. This process creates polygons within which many peat areas fall when a union that includes MGS surficial geology is performed. These peat areas can then be delineated by selecting those which fall "within" till areas and those which do not. However, many peat polygons are on "edges" of till areas, and would therefore not have ended up "inside" the till area outline created by this processes. In fact, it is difficult to know whether or not a given peat polygon on the "edge" of a till area should be considered 'peat over till,' or 'peat not over till.' Hua Zhang selected several "edge" peat polygons which were subsequently added to the till outline coverage, in effect broadening the geographic scope of this (till) coverage so that it subsumes those polygons after the union is performed. Other "edge" peat polygons were considered 'peat NOT over till, along with the peat polygons that are completely outside of till areas. Surficial Geology from the Minnesota Geological Survey (SGPG) This polygon coverage was created by the MGS, and is displayed on Plate 3 of The Stearns County Geologic Atlas, Part A. Relative permeability of different geologic types was estimated by Hua Zhang, and used in assessing pollution sensitivity values. See Ratings Matrix on Stearns County Geologic Atlas, Part B, Plate 10 for more detailed information. COMBINING, DISSOLVING, SIMPLIFYING, AND ADDING ITEMS The above four layers were combined using the ARC command 'union.' The item 'senrating' was added (See Enity and Attribute information below), and was calculated using an ARC AML based on criteria outlined in Plate 10 of The Stearns County Geologic Atlas, Part B. The coverage was dissolved on the item 'senrating, and polygons 20,000 sq meters or smaller were removed with the ARC command 'eliminate.' Finally, the item 'sensymbol' was added and calculated as shown in 'Entity and Attribute Information' (below). |
Source Scale Denominator | 1:100,000 |
Section 3 | Spatial Data Organization Information |
Native Data Set Environment | ARC/INFO 7.1.1 |
Geographic Reference for Tabular Data | |
Spatial Object Type | Vector |
Vendor Specific Object Types | Polygon |
Tiling Scheme | County |
Section 4 | Spatial Reference Information |
Horizontal Coordi651te Scheme | UTM |
Ellipsoid | GRS 1980 |
Horizontal Datum | NAD83 |
Horizontal Units | N.A. |
Altitude Datum | N.A. |
Altitude Units | N.A. |
Depth Datum | N.A. |
Depth Units | N.A. |
Cell Width | N.A. |
Cell Height | N.A. |
UTM Zone Number | 15 |
Coordinate Offsets or Adjustments | None |
Distance Resolution |
Section 5 | Entity and Attribute Information | ||||
Entity and Attribute Overview | |||||
Entity and Attribute Detailed Citation | |||||
Table Name | Field Name | Begin Column | Definition | Description | |
gwsl3py.pat | Polygon Attribute Table | ||||
SENRATING | 25 | Pollution sensitivity rating based on estimated vertical travel time for water-borne surface contaminants to reach the aquifer. | |||
'NR' | Not rated (Mostly open water) | ||||
'VH' | Very high - Hours to months | ||||
'H' | High - Weeks to years | ||||
'M' | Medium - Years to decades | ||||
'L' | Low - More than a century | ||||
SENSYMBOL | 27 | 2,2,i | Pollution sensitivity rating as a number | ||
0 | Not rated | ||||
1 | Very high | ||||
2 | High | ||||
3 | Medium | ||||
4 | Low |
Section 6 | Distribution Information |
Publisher | Minnesota Department of Natural Resources |
Publication Date | 1999 |
Online Linkage | |
Distributor Contact Person | See METADATA CONTACT PERSON (below) |
Distributor Organization | " |
Distributor Position | " |
Distributor Address | " |
Distributor City | " |
Distributor State or Province | " |
Distributor Postal Code | " |
Distributor Voice Phone | " |
Distributor Fax Phone | " |
Distributor E-mail Address | " |
Distributor's Data Set Identifier | |
Distribution Liability | This map was prepared from publicly available information only. Every reasonable effort has been made to ensure the accuracy of the factual data on which this map is based. However, the Department of Natural Resources does not warrant the accuracy, completeness, or any implied uses of these data. Users may wish to verify critical information; sources include both the references here and information on file in the offices of the Minnesota Geological Survey and the Department of Natural Resources. Every effort has been made to ensure the interpretation shown conforms to sound geologic and cartographic principles. This map should not be used to establish legal title, boundaries, or locations of improvements. |
Transfer Format Name | ARC/INFO, ArcExport, INFO |
Transfer Format Version Number | 7.1.1 |
Transfer Size | |
Ordering Instructions | Download Arc/INFO export file or ARCVIEW shapefile from Stearns County Geologic Atlas, Part B: Metadata for GIS and Digital Data |
Section 7 | Metadata Reference Information |
Metadata Date | |
Metadata Contact Person | Randy McGregor |
Metadata Contact Organization | Minnesota Department of Natural Resources |
Metadata Contact Position | GIS Specialist |
Metadata Contact Address | 500 Lafayette Road |
Metadata Contact City | St. Paul |
Metadata Contact State or Province | MN |
Metadata Contact Postal Code | 55155 - 4032 |
Metadata Contact Voice Phone | (651) 297 - 4591 |
Metadata Contact Fax Phone | (651) 296 - 0445 |
Metadata Contact E-mail Address | [email protected] |
Metadata Standard Name | Minnesota geographic Metadata Guidelines |
Metadata Standard Version | 1.0.4 |
Metadata Standard Online Linkage |