Stratigraphy

Start Depth
End Depth
Stratigraphic Unit
Start Depth: 0.00 ft
End Depth: 15.00 ft
Unit: Quaternary 
System
Quaternary 
Series
 
Group
 
Formation
 
Member
 
Submember
 
Start Depth
0.00 ft
End Depth
15.00 ft
Contact Accuracy
Contacts Poorly Defined Or Complete Gap 
Penetration
Complete Gap 
Primary Lithology
Unknown 
Percent
Secondary Lithology
Unknown 
Percent
Tertiary Lithology
Unknown 
Percent
Comments
Start Depth: 15.00 ft
End Depth: 40.00 ft
Unit: Pre-Illinoian 
System
Quaternary 
Series
Pleistocene Series 
Group
Pre-Illinoian 
Formation
 
Member
 
Submember
 
Start Depth
15.00 ft
End Depth
40.00 ft
Contact Accuracy
Base Accurate, Top Less Accurate - (Poor Samples, Gap At Contact) 
Penetration
Complete Penetration, Gap At Top 
Primary Lithology
Till - Unoxidized And Unleached 
Percent
100 
Secondary Lithology
Unknown 
Percent
Tertiary Lithology
Unknown 
Percent
Comments
Start Depth: 40.00 ft
End Depth: 45.00 ft
Unit: Pre-Illinoian 
System
Quaternary 
Series
Pleistocene Series 
Group
Pre-Illinoian 
Formation
 
Member
 
Submember
 
Start Depth
40.00 ft
End Depth
45.00 ft
Contact Accuracy
Top & Base Accurate For Sample 
Penetration
Complete Penetration, No Gaps 
Primary Lithology
Till - Oxidized And Unleached 
Percent
100 
Secondary Lithology
 
Percent
Tertiary Lithology
 
Percent
Comments
Start Depth: 45.00 ft
End Depth: 120.00 ft
Unit: Pre-Illinoian 
System
Quaternary 
Series
Pleistocene Series 
Group
Pre-Illinoian 
Formation
 
Member
 
Submember
 
Start Depth
45.00 ft
End Depth
120.00 ft
Contact Accuracy
Top & Base Accurate For Sample 
Penetration
Complete Penetration, No Gaps 
Primary Lithology
Till - Unoxidized And Unleached 
Percent
100 
Secondary Lithology
 
Percent
Tertiary Lithology
 
Percent
Comments
Start Depth: 120.00 ft
End Depth: 125.00 ft
Unit: Pre-Illinoian 
System
Quaternary 
Series
Pleistocene Series 
Group
Pre-Illinoian 
Formation
 
Member
 
Submember
 
Start Depth
120.00 ft
End Depth
125.00 ft
Contact Accuracy
Top & Base Accurate For Sample 
Penetration
Complete Penetration, No Gaps 
Primary Lithology
Sand And Gravel 
Percent
100 
Secondary Lithology
 
Percent
Tertiary Lithology
 
Percent
Comments
Start Depth: 125.00 ft
End Depth: 180.00 ft
Unit: Pre-Illinoian 
System
Quaternary 
Series
Pleistocene Series 
Group
Pre-Illinoian 
Formation
 
Member
 
Submember
 
Start Depth
125.00 ft
End Depth
180.00 ft
Contact Accuracy
Top & Base Accurate For Sample 
Penetration
Complete Penetration, No Gaps 
Primary Lithology
Till - Unoxidized And Unleached 
Percent
100 
Secondary Lithology
 
Percent
Tertiary Lithology
 
Percent
Comments
Start Depth: 180.00 ft
End Depth: 305.00 ft
Unit: Woodbury 
System
Cretaceous 
Series
 
Group
Fort Benton ("Lower Colorado ") 
Formation
Dakota 
Member
Woodbury 
Submember
 
Start Depth
180.00 ft
End Depth
305.00 ft
Contact Accuracy
Top & Base Accurate For Sample 
Penetration
Bedrock Surface - Partial Penetration (Base Not Met), No Gap At Top 
Primary Lithology
Shale 
Percent
Secondary Lithology
Siltstone 
Percent
Tertiary Lithology
Sandstone 
Percent
Comments
Start Depth: 278.00 ft
End Depth: 305.00 ft
Unit: Nishnabotna 
System
Cretaceous 
Series
 
Group
Fort Benton ("Lower Colorado ") 
Formation
Dakota 
Member
Nishnabotna 
Submember
 
Start Depth
278.00 ft
End Depth
305.00 ft
Contact Accuracy
Base Accurate, Top Less Accurate - (Indistinct Lithologic Contact) 
Penetration
Bedrock Surface - Partial Penetration (Base Not Met), No Gap At Top 
Primary Lithology
Sandstone 
Percent
100 
Secondary Lithology
 
Percent
Tertiary Lithology
 
Percent
Comments