AGGREGATE RESOURCE POTENTIAL

ISANTI COUNTY, MINNESOTA



Field

Description

Main ID Information

Metadata Updated 2007

Title

Aggregate Resources and Quaternary Geology of Isanti County, Minnesota. This layer is part of Minnesota Department of Natural Resources, Minerals Division, Report 304, from 1992.

Filename

sg92xpy3, sg92xln3, and sym92ln3

Abstract

This dataset consists of information about surficial geology and aggregate resource potential, based on geological factors. This work is authorized by Minnesota Statute 84.94.

Place Keywords

Isanti County, MN

Theme Keywords

Aggregate resource potential, geological characteristics

Time Period of Content

1990-1991

Parent Theme

 

Spatial Extent of the Data

Isanti County, Minnesota

Contact Person

Aggregate Resources Mapping Program

Contact Person Organization/Division

Minnesota 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, MN

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 aggregate resource potential of the various mapping units.

Progress

Complete

Currentness Reference

Air photo interpretation 1990-1991, field work summers of 1990 and 1991.

Maintenance Frequency

None planned

Access Constraints

NA

Use Constraints

NA

Associated Data Sets

shapefiles: sg92xln3, sym92ln3, gp92apt3, gp92bpt3

Access database: isanapot.mdb

Data Quality

 

Attribute Accuracy

The mapping units were compiled onto 1:24,000 USGS topographic maps. These delineations and unit descriptions were field checked and revised. The coverage was created by digitizing the delineations after registering the USGS maps on a digitizing table.

Logical Consistency

NA

Completeness

The units were delineated by aerial photograph interpretations. The potential of deposits is based on geologic factors, not economic factors. Generalizations were made, resulting in a product that should be considered reconnaissance level and accurate to a scale of 1:70,000.

Horizontal Positional Accuracy

1:70,000

Vertical Positional Accuracy

NA

Lineage

These shapefiles are part of Minnesota Department of Natural Resources, Minerals Division, Report 304, Aggregate Resources and Quaternary Geology, 1992, by JD Lehr.

The data were compiled in a multi-step process. The first step developed a preliminary Quaternary geology legend after a review of the literature of glacial geology in east-central Minnesota. The map units were based on the principle that glacial depositional environments can be mapped based upon their landform expression. Additional map units were included to provide detail within potential aggregate units.

Next, subsurface data were added to the compilation maps to supplement the geologic inferences, including well logs, stored in a database at the Minnesota Geological Survey entitled County Well Index (i.e., CWI) and Minnesota Department of Transportation gravel pit sheets, including shallow (10-40') test-hole logs, sieve, and quality test data.

Gravel pit locations were also added to the compilation maps and were gathered from a number of sources, including the Soil Survey of Isanti County (from the Soil Conservation Service), 15-minute USGS topographic maps, Minnesota Department of Transportation Isanti County Highway Map, Isanti County Highway Department, and field observations by the author, JD Lehr.

At this point, mapping units were delineated on 1:24000 USGS topographic maps using stereographic photo pairs at a scale of 1:90000.

During the summers of 1990 and 1991, the author made observations of the landform expression and surficial sediment, as exposed in gravel pits, road cuts, natural exposures, and excavations. Where exposures were lacking, sediment from shallow, hand-augured holes were described.

After the field work, the compilation maps were reexamined in relation to the air photos, scholarly review, and the plotted subsurface data, and adjustments were made to the mapping units as necessary.

Source Scale Denominator

1:62,500

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

15, extended

Raster only

 

Cell Width

NA

Cell Height

NA

Spatial Data Organization

 

Geographic Reference for Tabular Data

NA

Native Dataset Environment

ArcView 3.1 / Arc/INFO 7.2.1

Vendor Specific Object Type

NA

Tiling Scheme

County/township

Spatial Object Type

Vector-polygon

Transfer Size



Entities -- Attributes

 

Entity-Attribute Overview

Quaternary geology mapping units, aggregate resource potential units based on geological factors

Entity-Attribute Detailed Citation

The basic relationships among the attributes are as follows:

Geo_unit Geo_label Lobe Deposit Aggregate Mantle

-------------------------------------------------------------------------------------------------------------------------

10 O Organic

15 Al Alluvium

20 Dlc Grantsburg Lacustrine deposits - coarse

21 Dlf Grantsburg Lacustrine deposits - fine

23 Doc Grantsburg Collapsed outwash Y

24 Di Grantsburg Ice-contact stratified deposits Y

25 Docm Grantsburg Mantled collapsed outwash Y M

27 Dt Grantsburg Till

28 Dotl Grantsburg Lake-modified till

32 Som Superior Mantled outwash Y M

33 Soml Superior Mantled outwash Y ML

34 Si Superior Ice-contact stratified deposits Y

35 Sim Superior Mantled ice-contact stratified deposits Y M

36 Siml Superior Mantled ice-contact stratified deposits Y ML

37 St Superior Till

39 Stml Superior Mantled till ML

89 W Water (River)

99 W Water (Lake)



Table Name

Field Name

Begin Column

Definition

Valid Values

Descriptions

sg92xpy3 shapefile

 

 

 

 

Quaternary geology polygons

 

geo_unit

 

Number,2,0

10,15,

20,21,

23,25,24,

27,28,

32,33,

34,35,36,

37,39,

89,99

Quaternary (i.e., surficial) geology units, given as a number

 

geo_label

 

Text,4

O,Al,

Dlc,Dlf,

Doc,Docm,Di,

Dt,Dtl,

Som,Soml,

Si,Sim,Siml,

St,Stml,

W,W

Quaternary (i.e., surficial) geology units, given as a character string (presented in the same order as above, for geo_unit)

 

lobe

 

Text,10

Superior, Grantsburg

Age of material in the mapping unit, based on lobe or sublobe

 

deposit

 

Text,40

e.g., Organic, Alluvium, Outwash, Ice-contact stratified deposits, Till, Water

Type of deposit. Refer to the "Entity-Attribute Detailed Citation" listed prior to this table for the relationships among the various attributes.

 

aggregate

 

Text,1

 

Flagged with a Y if the mapping unit has aggregate resource potential; flagged with a N if it does not.

 

 

 

 

Y

Those geologic units that are inferred to contain potentially significant aggregate deposits. Gravel pits and aggregate sources (from gp92xpt3) indicate identified resources.

 

 

 

 

N

Those geologic units that generally have little or no potential for aggregate resources. In places, includes aggregate deposits either too small or too difficult to map.

 

mantle

 

Text,2

M = mantled by another mapping unit, ML = mantled by Dlf (i.e., Lacustrine deposits - fine) unit

The mapping unit is mantled by another mapping unit

 

major_lith

 

Text,30

O-peat, Al-sand, Dlc-fine sand, Dlf-silt, Doc-sand and gravel, Docm-sand and gravel, Di-sand and gravel, Dt-till, Dtl-till, Som-sand and gravel, Soml-sand and gravel, Si-sand and gravel, Sim-sand and gravel, Siml-sand and gravel, St-till, Stml-till

Major lithology of mapping unit, presented here in relation to geo_label. That is, geo_label-major_lithology description

 

minor_lith

 

Text,30

O-organic-rich silt, Al-organic-rich silt, Dlc-silt, Dlf-clay,

Di-silty sand, Dtl-silt, Som-silt, Soml-silt, Si-till, Sim-till, Siml-till

Minor lithology of mapping unit, presented here in relation to geo_label. That is, geo_label-minor_lithology description.

 

mantl_lith

 

Text,35

O-none, Al-none, Dlc-none, Dlf-none, Doc-none, Docm-undiff. Grantsburg sublobe deposits, Di-none, Dt-in places, fine sand, Dtl-in places, silt, Som-undiff. Grantsburg sublobe deposits, Soml-silt, Si-none, Sim-undiff. Grantsburg sublobe deposits, Siml-silt, St-none, Stml-silt

Lithology of the mantle unit found in this mapping unit, presented here in relation to geo_label. That is, geo_label-mantl_lithology description.

sg92xln3 shapefile

 

 

 

 

Quaternary geology polygon boundaries, stored as an arc coverage

 

contact

 

Number,3,0

12,14,42,60,70,89,99,131

Polygon boundary, given as a number, when layer digitized

 

conttype

 

Text,70

Meltwater channel; Meltwater channel; Ice-contact face; Geologic contact; Geologic contact - inferred, gradational, or approximately located; River boundary; Lake boundary; County boundary

Polygon boundary, given as a text description, when digitized (presented in the same order as above, for contact)

 

cont4map

 

Number,3

60,60,60,60,70,99,99,131

Polygon boundary, given as a number, used when mapped (given in same order as above, for contact)

 

c4maptype

 

Text,70

Geologic contact; Geologic contact; Geologic contact; Geologic contact; Geologic contact - inferred, gradational, or approximately located; Water boundary; Water boundary; County boundary

Polygon boundary, given as text, used when mapped (given in same order as above, for contact)

sym92ln3 - associated geology line shapefile

 

 

 

 

Geologic landforms, stored as lines

 

landform

 

Number,2,0

11,13,20,30,41,60,70,75

Type of landform, stored as a number

 

lformtype

 

Text,30

Meltwater channel (right side as look downstream), Meltwater channel (left side as look downstream), Meltwater flow direction, Crests of ridges (formed parallel to the margin of the Grantsburg sublobe), Ice-contact face, Esker (direction of line points in direction of meltwater flow), Drumlin (Long axis of Superior lobe drumlin, direction of line points in direction of ice flow), Drumlin - buried (Long axis of buried Superior lobe drumlin, direction of line points in direction of ice flow)

Description of the landform type (presented in the same order as above, for landform)