Academic Integrity: tutoring, explanations, and feedback — we don’t complete graded work or submit on a student’s behalf.

Use the geologic map in figure 13.12 in your lab manual to help answer a series

ID: 284565 • Letter: U

Question

Use the geologic map in figure 13.12 in your lab manual to help answer a series of questions regarding this map

Which of the following Paleozoic ad Mesozoic time periods are represented in the map area?

Triassic

Jurassic

Cretaceous

Tertiary

All of the above

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

Which of the following Paleozoic time periods is NOT represented in the map area?

Cambrian

Silurian

Carboniferous

Permian

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

The contact between Precambrian rocks and the Cambrian Deadwood Formation is a strongly curved line on this map because of many small valleys cut into the contact that dip consistently to the east. What is the nature of this contact?

A fault that has thrust Precambrian rocks over Cambrian rocks

An unconformity (nonconformity) where Cambrian rocks were deposited over Precambrian rocks

A normal fault that dips to the west.

An intrusive contact between the metamorphic rocks and the sandstone.

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

What is the nature of the contact between the Deadwood Formation and the Englewood Limestone?

A fault that has thrust the Deadwood Formation over the Englewood Limestone.

disconformity between the two east-dipping units

A normal fault that dips to the west

The two units are not in contact.

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

In following the contact between the Skull Creek Shale and the Sundance Formation from south to north across the map, which of the following is observed?

The Morrison Formation is locally preserved between the two units.

The Spearfish Formation locally crosses the Sundance Formation to contact the Skull Creek Shale.

The two units are not in contact.

The two units are everywhere in direct contact across the map.

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

Which of the following units are in contact with the base of the White River Group?

The Greenhorn limestone

Mowri shale

Sundance Fornation

The Minnelusa SandStone

All of These

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

What is the nature of the contact between the White River Group with the underlying formations?

conformable contact.

intrusive contact.

angular unconformity

thrust fault.

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

The east-dipping units are part of the Black Hills uplift. Based on relationships in the map area, what is the age of this tilting?

Between the Precambrian and Cambrian.

Between the Permian and Triassic

Between the Triassic and Jurassic

Between the Jurassic and Cretaceous.

Between the Cretaceous and Tertiary.

Use the geologic map in figure 13.12 in your lab manual to help answer a series of questions regarding this map

peg p Esq p Eg 45 FIGURE 13.12 TERTIARY Tw p Esq White River Group CRETACEOUS Tw LT Kg 41 17 Greenhorn Limestone Kbm Mowry Shale Ks. 45 Skull Creek Shale JURASSIC Ed Jm Jm Cm Morrison Formation US A Tw RS Sundance Formation Pm TRIASSIC Ks Rs Spearfish Formation PERMIAN Tw Kbma p Eg Pm Minnekahta Formation CARBONIFEROUS 43 38 Cm Minnelusa Sandstone Englewood Limestone CAMBRIAN R35 Tw Deadwood Formation Cm PRECAMBRIAN bm p Eg granite and pegmatite p Esq miles metamorphic rocks Colored geological map of the southeastern portion of the Black Hills, South Dakota

Explanation / Answer

1) Triassic, Jurassic and Cretaceous are represented in the map area

2) Silurian

3) An unconformity (nonconformity) where Cambrian rocks were deposited over Precambrian rocks

4) disconformity between the two east-dipping units

5) The Morrison Formation is locally preserved between the two units.

6) All of these- the base of the White River Group is contact with The Greenhorn limestone, Mowri shale, Sundance Fornation, The Minnelusa SandStone and Minnekahta formation

7)angular unconformity

8) Between the Precambrian and Cambrian.

Hire Me For All Your Tutoring Needs
Integrity-first tutoring: clear explanations, guidance, and feedback.
Drop an Email at
drjack9650@gmail.com
Chat Now And Get Quote