COUNTY WELL INDEX (CWI) - GEOLOGICAL DESCRIPTIONS

DODGE COUNTY, MINNESOTA

 

Field

Description

Main ID Information

Metadata Updated 2007

Title

Dodge County Aggregate Evaluation -CWI Geological Descriptions Table

Filename

Cwistrat (DataBase File)

Abstract

This dataset consists of a subset of the geological description attributes listed within the CWI database from the Minnesota Geological Survey.  It lists the unique identifier, the depth to the top of interval and the driller’s description of the material encountered.

Place Keywords

Dodge County, Minnesota

Theme Keywords

CWI, County Well Index, Geological Descriptions

Time Period of Content

Downloaded in 2000

Parent Theme

NA

Spatial Extent of the Data

Dodge County, Minnesota

Contact Person

Aggregate Resources Mapping Program

Contact Person Organization/Division

Department of Natural Resources, Division of Lands and Minerals

Contact Person Position

Geologist or GIS Specialist

Contact Address

500 Lafayette Road, Box 45

Contact City

St. Paul

Contact Zip Code

55155-4045

Contact Voice Phone

651-259-5959

Contact Fax Phone

651-296-5939

Additional ID Information

 

Originator

Minnesota Geological Survey

Purpose

This data set was used to help interpret the aggregate resources, surficial geology, and geological history of Dodge County.  This dataset consists of the geological description used within the CWI database.  It lists the unique identifier, the depth to the top of interval and the drillers description of the material encountered.

Progress

Complete

Currentness Reference

2000

Maintenance Frequency

None planned

Access Constraints

NA

Use Constraints

NA

Associated Data Sets

Cwiwells - one-to-many (cwiwells-to-cwistrat) - relate on relateid.

Data Quality

 

Attribute Accuracy

Descriptions were made by several different drillers and geologists.  The information within them ranges from very good to very poor.  The thickness are generally estimated to within a few feet and the descriptions may vary from hole to hole due to many different individuals completing the logging.

Logical Consistency

NA

Completeness

Some of the geological descriptions are very complete, while others are very vague.  Ex: the detailed descriptions may be broken down every 5 to 10 feet describing the glacial material and bedrock formations; others may just say 0-240 glacial drift, 240-360 sandstone.

Horizontal Positional Accuracy

NA

Vertical Positional Accuracy

NA

Lineage

Descriptions were made by several different drillers and geologists.  The information within them ranges from very good to very poor.  The thickness is generally estimated to within a few feet and the descriptions may vary from hole to hole due to many different individuals completing the logging.

Source Scale Denominator

NA

Spatial Reference

 

Horizontal Coordinate Scheme

NA

Ellipsoid

NA

Horizontal Datum

NA

Horizontal Units

NA

Distance Resolution

NA

Altitude Datum

NA

Altitude Units

NA

Depth Datum

Drilled and logged wells.

Depth Units

Feet

UTM Zone Number

NA

Raster only

 

Cell Width

NA

Cell Height

NA

Spatial Data Organization

 

Geographic Reference for Tabular Data

These points are located throughout Dodge County (usually near farms).

Native Dataset Environment

ArcView 3.1 / ArcInfo 8.0.2

Vendor Specific Object Type

NA

Tiling Scheme

County

Spatial Object Type

Point

Transfer Size

268 kb

Entities -- Attributes

 

Entity-Attribute Overview

This dataset consists of the geological description used within the CWI database.  It lists the unique identifier, the depth to the top of interval, and the driller’s description of the material encountered.

Entity-Attribute Detailed Citation

See table below:

 

 

Table Name

Field Name

Begin Column

Definition

Valid Values

Descriptions

Cwistrat.dbf

Relateid

 

Text, 10

Ex: 000101209

This is the unique well identifier used by the MGS to reference the well (Relate item with cwistrat).

 

Depth_top

 

Number, 6, 0

Ex:  2, 4, 8, 240

Depth to the top of interval in feet.

 

Depth_bot

 

Number, 6, 0

Ex:  2, 4, 8, 240

Depth to the bottom of interval in feet.

 

Drllr_desc

 

Text, 34

Ex: Clay, Sand, Limestone

Material that drillers encountered while drilling the well.

 

Color

 

Text, 8

Ex: Yellow, Blue, Gray

Color of rock