Virginia’s Physiographic Provinces

Area defined by geologic activity, rock type, and age

Provinces

12

3

4

5

1. Coastal Plain (flat)2. Piedmont (rolling hills)

3. Blue Ridge (mountains)

4. Valley and Ridge (mountains)

5. Appalachian Plateau (elevated flat land)

Fall line rapid change in elevation

1. Coastal Plain

Rock / Age Resources TopographySedimentary

1-140 myoClayOil and gas (offshore) Sand and gravel

Geologic Activity:CP = product of erosion of the Appalachian Mountains and oceanic sedimentary deposits.

1

•Flat (less than 50 m)• bordering the Chesapeake Bay and the Atlantic Ocean

2. Piedmont2

This area is the product of convergence

(plates moving together)

RockMetamorphicIgneousSedimentary

ResourcesSoapstone Slate GoldPyrite VermiculiteIron ZincCopper Coal

TopographyRolling hills

Geologic Activity•Folding•Faulting (earthquakes)•Intrusions (magma)

3. Blue Ridge 3

Rock / Age Resources Topography

MetamorphicIgneous1.2 byo

Copper Tin Iron GraniteTurquoiseQuartzite

The Blue Ridge is a high ridge separating the Piedmont and the Valley. It is a result of convergence.

Mountains

Ridges

Geologic Activity:•Folding•Faulting (earthquakes)•intrusions

4. Valley and Ridge 4

Rock and Age Resources Topography

Sedimentary300-550myo

Lime Zinc Gypsum Lead Iron Limestone

Mountains

*This area is the result of convergence between Africa and North America.

Geologic Activity:

•Folding

•Faulting (earthquakes)

•Karst

5. Appalachian Plateau

5

Rock and Age Resources Geologic Activity

Sedimentary280-320myo

Coal OilNatural gas

FoldingFaulting

(earthquakes)

*This area is the result of uplift from the convergence of plates. It is no longer a flat-topped area due to weathering and erosion.

Topography:

Used to be high, flat area, now hills

Watershed

Virginia has nine major river systems. •The New, Tennessee and Big Sandy empty (shed) into the Gulf of Mexico. •The Chowan and Roanoke empty (shed) into the Albemarle Sound. •The Potomac-Shenandoah, Rappahannock, York, and James empty (shed) into the Chesapeake Bay.

The area of land where all of the water that is under it or falls on it drains into the same place.

Chesapeake Bay Watershed

15 MILLION people live in this watershed!

Chesapeake Bay Watershed• Major Sources of Pollution

– Runoff (non point source!)• Fertilizers, pesticides, oil, other chemicals from

roadways, animal wastes

• The Solution?– Reduce chemical use– Natural filters

Consolidation and Water Quality

Virginia is underlain by igneous, metamorphic and sedimentary rocks. Throughout the five provinces sedimentary is the dominant rock type.

When the rock sediments have enough space for water and air to move through (porous), the water is naturally filtered. As the rock becomes more consolidated (less pore space for water movement), the water is not able to filter naturally.

Rock type and consolidation (how tightly packed the grains are within the sediment or bedrock), and age all contribute to the quality of groundwater.

As compaction increases water quality decreases.

Space No Space

As compaction increases,Water Quality decreases.

*Best*Worst