Download File - Vagabond Geology

University of Texas, Life Long Learning
SAGE: Winter 2011
Vagabonds tramping geology
in Iberia, France, UK, & Germany
Don Beaumont, Sandi Phillips, & Rocky Romero
Sessions 1 and 2
Iberian Peninsula
Portugal and Spain
Civilization exists by geologic consent, subject to change without notice.
Will Durant
Senior University Georgetown
Winter 2011
Vagabonds tramping geology
Don Beaumont, Sandi Phillips, & Rocky Romero
Sessions 1 and 2
Iberian Peninsula
Portugal and Spain
Civilization exists by geologic consent, subject to change without notice.
Will Durant
Senior University Travels
GEOLOGY WITH DON BEAUMONT
Thursday, March 10, 2011
8 a.m. - 5:30 p.m.
Tracing the 65 million year old Balcones Fault and 100 million year
old Edwards Limestone Aquifer from Georgetown to Austin,Texas
Join us as we follow the Balcones Fault and Edwards Aquifer from the Georgetown
Airport where the fault begins and shallow water wells can be drilled to the Edwards
limestone. Then we visit the Buie Ranch where we learn how unpredictable drilling
for water can be. At nearby Berry Springs Park we will explore one of five major
Edwards springs that attracted early settlers to the Georgetown area. Driving south
on IH-35 we will learn why Inner Space Cavern and the Texas Crushed Stone
Quarry are located here and what caused the prominent ridge on which LaFrontera
shopping mall is built. Driving down Route 1 we will follow the fault to its greatest
vertical displacement at Mount Bonnell. Then it is lunch at the Oasis Restaurant on
the upthrown side of the fault followed by a river cruise viewing the river gorge
landscape created by the fault.
$78 per person
Includes motor coach, lunch, boat, refreshments, all gratuities,
Hosted by Babs Cape
Class has priority for reservations through February 4;
Open to membership February 5
EMAIL: [email protected] checks to POB 488, 78627
Geology in the News
Humans left Africa earlier than once thought
Austin American Statesman, January 28, 2011
It might have been like this
125,000 years ago to eastern Arabia rather than 100,000 years ago
into Palestine
Suggests new route directly from East Africa to Arabia rather than
up the Nile River and then through the Sinai.
Now to BP and Arctic Russia
BP to spend billions exploring for
oil & gas in the Kara Sea of
Arctic Russia
Kara Sea
Now to Western Europe and Iberia
North Sea
Countries of Western Europe
Iberia
Topographic Provinces
Topographic Provinces
Mountains, Plateaus, and River Low Lands
Geologic Map of
Western Europe
Colors relate provinces of the same age
Geologic Map
Colors show rocks of different:
1. ages
2. types
What are the earth’s rock types?
http://certmapper.cr.usgs.gov/data/envision/index.html?widgets=geologymaps&mapservice=ge
ology_europe&xmin=-35.79&xmax=55.75&ymin=27.96&ymax=74.57
Three Types of Rocks make up the Earth’s Crust
1. Sedimentary Rocks
2. Metamorphic Rocks
3. Igneous Rocks
Let’s look at sedimentary rocks
Portugal and Spain have all three rock types in a very complex pattern
Rocks: Types & Cycles
Sediments
Burial:
heat
pressure
Sedimentary Rocks
Common Sedimentary Rock Types
Common Sedimentary Rock Types
Limestones = sea shells & shell debris
Sandstones = sand
Shales = clay (mud)
Most sedimentary rocks are formed:
1. in the oceans
2. at the edge of the continents
Next: Metamorphic Rocks
Rocks: Classes & Cycles
Sediments
to
Sedimentary Rocks
Sedimentary Rocks
to
Metamorphic Rocks
Partial Melting
Common Metamorphic Rocks
Common Metamorphic Rocks
Limestone: partially melted = marble
Sandstone: partially melted = quartzite
Shale: partial melting = slate
Shale & Sand partial melting = schist = gneiss
Finally, igneous rocks
Rocks: Classes & Cycles
At the surface
molten Lava
Complete
Melting
At depth
molten
Magmas
Metamorphic Rocks
to
Igneous Rocks
Sedimentary Rocks
to
Metamorphic Rocks
Igneous Activity
Volcanic: At or near the surface of the earth
Plutonic: Well below the surface of the earth
(visible by deep erosion)
Now, at quick look at volcanic igneous rocks
Igneous Rocks
Volcanoes
From melted
oceanic crust
or shales
From melted
continental Crust
or sandstone & shale
Next: the Plutonic Igneous rocks
Basalt
Rhyolite
Dark color
Heavy
No “grains”
Light color
Medium weight
No “grains”
Plutonic (deeply buried)
Igneous Rocks
Mantle rock
Original rock below
the earth’s crust
Original Continental Crust
or
melted sandstone & shale
Putting it all together; our solid earth
Gabbro
Granite
The Solid Earth
The Rocky Igneous Crust
Continental
Granite: 20 to
50 miles thick
The Earth’s
Rocky Crust
Oceanic
Basalt
5 miles thick
5 to 50 miles thick
The Solid Earth
Continental
Granite
The Mantle
Composed of rock called gabbro
Where are sedimentary rocks created?
Oceanic
Basalt
Sedimentary Rocks
Where are they formed?
Continent being
Destroyed by
Weathering &
Erosion
Rivers move the
Continental Debris to the
Continental Margins
Where it is accumulates
as layers of sediments
Modern sediments of Iberia
Sediments (sands, muds, & shells) are buried
and squeezed into Sedimentary Rocks
Modern sediments of Iberia
Where & how are sedimentary rocks
converted to metamorphic rocks?
Where & how are sedimentary rocks
converted to metamorphic rocks?
Ocean
Rivers carry erosional debris to the
ocean at the continental margins
But first a word about the earth’s crust
Oceanic Crust:
Under all of the deep seas
About 5 miles thick
Continental Crust:
Comprises all continents
About 20 to 50 miles thick
Where & how are sedimentary rocks
converted to metamorphic rocks?
Sediments in ocean at the
margin of the continent
Building a new mountain range
by crushing & melting the
sedimentary rocks creating
metamorphic rocks
Where have sedimentary rocks in North America
been converted to metamorphic rocks?
Where are
Metamorphic & Igneous Rocks Made?
Note: Iberia has Appalachian age mountains!
How do we explain this?
Debris along continental margins
is crushed and melted when crustal plates collide
forming Metamorphic and Igneous Rocks
Appalachian age mountains
Alpine (“recent”)
age mountains
Where and how did this happen?
The Crushing and Melting
when Africa collided with
North America to produce
Metamorphic & Igneous Rocks
of the Appalachian Mountains
Before we continue with the history
of Appalachia and Iberia:
Geologic Time
Iberia
On a collision course
Geologic Time: The Last 570 Million Years
Collision!! Mountains in Appalachia, Iberia, France, Scotland & Norway
North America & Africa (Iberia, etc) on a collision
course
Last
slide
The Crushing and Melting when
Africa collided with North America
creating Metamorphic & Igneous rocks
in Appalachia, Iberia, France, Scotland & Norway
Crunch!!!!
Mountain ranges created by
collision of earth plates
Crust broken into PLATES
North American Plate
Eurasian Plate
African Plate
Plate motion: Continental Drift
Plates move (drift) slowly
colliding & shearing each other
Continental (plate) Drift
Appalachian Mountains
North America & NW Europe
Focusing on western Europe
Super continent
Pangaea
South America, Florida,
Africa & SW Europe
Continental (plate) Drift
European “Appalachians”
Modern World
Mountain Ranges
From Blakey
Modern World
Mountain Ranges
From Blakey
North Atlantic: Close Up
Modern World
Mountain Ranges (blue)
From Blakey
Back to Iberia: The Geologic Map
Iberia: The Geologic Map
Colors show rocks of differen
1. ages
2. types
Iberia: The Geologic Map
This map shows the present day rock surface produced by the
weathering & erosion of the complex continental crust of Iberia
Why is this important?
Weathering & Erosion of different rocks
produces different topographies & soils
Different topographies & soils determine
where humans live and flourish
Colors show rocks of different:
1. ages
2. types
Weathering & Erosion
Topography and Soils
Geologic Map
Rock Types at the surface
Natural Resources Map
Farming & Mining (Ores)
Weathering and Erosion also exposes
different ores at or near the surface
The mineral resources of Iberia
Human history has been shaped by
Proposition:
Rocks of different typesof
weather
& erode
the
possession
ore
Why are ore occurrencesdeposits
important?
producing different soilsBeaumont,
that determine
agriculture
Univ type
PennofSPP
paper 203, 2010