FIELD OBSERVATIONS

DODGE COUNTY, MINNESOTA

 

Field

Description

Main ID Information

Metadata Updated 2007

Title

Dodge County Aggregate Resource Evaluation - Field Observations

Filename

Fieldobs  (ArcView Shapefile)

Abstract

This dataset includes information gathered in the field.  Fieldwork was completed in the fall of 2001 and spring of 2002.  It includes approximately 420 field observation sites within Dodge County and contains a field description of each site, the dominant type of material encountered, the source of information, type of site, unit thickness, and overburden thickness.

Place Keywords

Dodge County, Minnesota

Theme Keywords

Field Observations, Aggregate Resources, Surficial Geology

Time Period of Content

2001

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

Department of Natural Resources, Division of Lands and Minerals, Mineral Potential Section

Purpose

To summarize the field observations.  These observations were made to confirm air photo interpretations that identified potential aggregate bearing landforms.

Progress

Complete

Currentness Reference

All field observations were completed in the fall of 2001 and spring 2002

Maintenance Frequency

None Planned

Access Constraints

NA

Use Constraints

NA

Associated Data Sets

County Aggregate Mapping Program datasets for various counties, including data on sand and gravel potential, crushed stone potential, field observations, rock piles, and test pit quality data.

Data Quality

 

Attribute Accuracy

 

Logical Consistency

NA

Completeness

The data points were gathered at the location where field observations took place.  Additional information is given in the lineage section.

Horizontal Positional Accuracy

The differential correction of the GPS unit for GPS located sites is +/- 2 meters.  Some points were located on 1:24000 USGS topographic maps.

Vertical Positional Accuracy

 

Lineage

A GPS unit was used to determine some of the locations of the data points.  These points were then downloaded and slightly revised based on field observations, topographic maps, and aerial photographs.  The GPS unit (with differential correction) is accurate to approximately a few meters.  Other points were located on 1:24000 USGS topographic maps and 1:40000 aerial photographs.  These coordinates were then checked with field notes and topographic maps to assure accuracy.

Source Scale Denominator

24000

Spatial Reference

 

Horizontal Coordinate Scheme

UTM

Ellipsoid

GRS80

Horizontal Datum

NAD83

Horizontal Units

Meters

Distance Resolution

NA

Altitude Datum

NA

Altitude Units

NA

Depth Datum

NA

Depth Units

NA

UTM Zone Number

15E

Raster only

 

Cell Width

NA

Cell Height

NA

Spatial Data Organization

 

Geographic Reference for Tabular Data

NA

Native Dataset Environment

ArcView 3.1 and ArcInfo 8.0.2

Vendor Specific Object Type

Point

Tiling Scheme

County

Spatial Object Type

Point

Transfer Size

123 kb

Entities -- Attributes

 

Entity-Attribute Overview

This dataset consists of field observation site locations, type of site, unit thickness, and overburden thickness.  ArcView specific fields include shape (i.e., feature type = point), area (0 for points), perimeter (0 for points), fieldobs_ (unique id for point, assigned by software), fieldobs_id (an id usually assigned during theme creation.

Entity-Attribute Detailed Citation

The field observation specific attributes are described in the table below.

 

 

Table Name

Field Name

Begin Column

Definition

Valid Values

Descriptions

fieldobs.dbf

Ident

 

Text, 24

Ex: 001, A-1, B-3, etc…

Unique Identifiers used in the field, letters have no significance. 

 

Lat

 

Number, 12, 8

44.0610976

Latitude locations identified by a GPS unit.

 

Long

 

Number, 12, 8

-92.75199481

Longitude locations identified by a GPS unit.

 

Site_type1

 

Text, 16

Drill Hole

Test hole drilled with a Giddings Soil Probe.

 

 

 

 

Excavation

Badger Holes, Trenches, Construction Areas, or Foundations

 

 

 

 

Exposure

Bedrock exposures.

 

 

 

 

Gravel Pit

Gravel Pits Exposing Sand and Gravel Material.

 

 

 

 

Outcrop

Stream, Road-Cut, Bank, Judicial Ditch, or Slump.

 

 

 

 

Quarry

An existing quarry exposing bedrock.

 

 

 

 

Other

Observed Vegetative trends, story of a land owner, etc...

 

Site_type2

 

Text, 16

Back Hoe

A hole dug by a back hoe.

 

 

 

 

Basement

Excavation of a basement.

 

 

 

 

Bees Nest

Mound in earth occupied by bees/ flying insects.

 

 

 

 

Burrow Pit

A mined pit for construction material

 

 

 

 

Construction

Mining for fill material and/or other construction.

 

 

 

 

Ditch

Material exposed in a ditch due to a slump or landscaping that has removed vegetation.

 

 

 

 

Drill Hole

Test hole drilled with an 8 inch auger.

 

 

 

 

Foundation

Material exposed in the digging of a basement/foundation.

 

 

 

 

Gravel Pit

Materials exposed in gravel pit.

 

 

 

 

Gully

Material exposed in a gully.

 

 

 

 

Hill Cut

Material exposed on a cow path.

 

 

 

 

Judicial Ditch

Materials exposed in manmade ditch.

 

 

 

 

Large Trench

Material exposed by trenching with bulldozer.

 

 

 

 

Ledge

Bedrock exposure as a ledge in a stream.

 

 

 

 

Quarry

Bedrock units exposed in a quarry.

 

 

 

 

Retaining Wall

Material exposed in a erosion of a retaining wall.

 

 

 

 

River Cut

Stream exposed an area.

 

 

 

 

Road Cut

Materials exposed in a road cut

 

 

 

 

Stream Sediment

Exposure of sediment in stream

 

 

 

 

Surface

Exposures of bedrock/material  on the ground surface.

 

 

 

 

Tiling Trench

Trenches for pipelines, tiling, cables, etc.

 

 

 

 

Tree Tip

Bedrock material exposed in the roots of a tree tip.

 

 

 

 

Trench

Any trench exposure of material.

 

 

 

 

Vegetation

Noting material by type of vegetation that grows on surface.

 

Field_stop

 

Number, 3, 0

0, 1, 2, 3, 4, 5, etc…

Unique identifiers for each field point.

 

Material_1

 

Text, 16

Ex: Sand, Gravel, Clay, Silt, Limestone, Sandstone.

Describes the primary type of material encountered at each observation site.

 

Material_2

 

Text, 16

Ex: Sand, Gravel, Clay, Silt, Limestone, Sandstone.

Describes the secondary (not primary) type of material at each observation site.

 

Fielddesc

 

Text, 80

Ex: Drill Hole (0-9 ft)  0-6 Till, 6-9 Gravel.

A short field description of the observation site.

 

Unitthick

 

Text, 8

Ex:0, 4, 5, 8, 12, >3, >5, >10, etc...

A description of the thickness of the unit in feet, with “<“ or “>” modifiers.

 

Overthick

 

Text, 8

Ex: <3, 6, <5, >5, >20, etc...

A description of the thickness of the overburden covering the unit, with “<“ or “>” modifiers.

 

Unitsamp

 

Text, 4

Yes or No

Indicates whether the material was sampled.  Not all sampled material was tested.

 

Gravelpct

 

Number, 11, 0

40, 30, 20

The estimated amount of gravel in the sample taken.

 

Thickmod

 

Text, 4

>

Modifies the Thick (i.e., Thickness field).  Greater Than

 

 

 

 

<

Less Than.

 

 

 

 

~

Approximately.

 

Thick

 

Number, 11, 0

Ex: 10, 15, 30, 40

Describes the thickness of the unit at the observation site in feet.

 

Overmod

 

Text, 4

>

Modifies the Over (Overburden Field). Greater Than.

 

 

 

 

<

Less Than.

 

 

 

 

~

Approximately.

 

Over

 

Number, 11, 0

Ex: 5, 10, 15, 20

The thickness of the overburden observed and estimated in feet.

 

Sampleid

 

Number,3,0

Ex:  23, 51

Sampleid is used to relate this shapefile to sieve.dbf.  These records are drill holes, which were sampled and tested for textural characteristics based on a sieve analysis.