SAGE Fall 2010 Session 3 Vagabonds Tramping Geology: Austin to Arctic Alaska Carlsbad to the Rio Grande Rift

The impatient thrust for scholarship is the secret of youthfulness: the undying flame that lights the human spirit

Senior University Fall 2010 Session 3 Vagabonds Tramping Geology: Austin to Arctic Alaska Carlsbad to the Rio Grande Rift

Senior University Fall 2010 Vagabonds Tramping Geology: Austin to Arctic Alaska Geologist: Don BeaumontVagabonds: Sandi Phillips & Rocky Romero From the Rio Grande Rift to the Mountain Ranges of Coastal California Session 2 Rio Grand Rift Western Horst

Rare earth metals are a collection of seventeen chemical elements in the periodic table, namely scandium, yttrium, and the fifteen lanthanides Uses: hybrid cars, superconductors, television sets, welding, munitions, etc Geology in the News

Large area of interior drainage due to glacier melting 12,000 years ago

Geology in the News From the minute to the sublime

Putting It All Together Last Glacial Maximum: 16,000 years ago

Geology in the News Carrizo Sandstone outcrop

Deposition and Burial before Uplift and Erosion Younger Cretaceous Older Cretaceous Carrizo Sandstone Area for Water wells

Geology in the News Carrizo Sandstone outcrop Giddings 290 Giddings Gas Fields

Geology in the News USA Territorial waters

Putting It All Together The Earth’s Amazing Living Crust Living: it reproduces itself Continental Crust: Periodically Renewed Oceanic Crust: Continuously Recycled

Granites first Foundation rocks of the continents Basalts & Gabbros next Foundation rocks below the deep oceans AND below the continental crust. After the atmosphere and oceans were formed: 4.8 billion years ago cooling of hot gases and dust created igneous rocks of the continents & oceanic crust Then the oceans and the atmosphere

After the atmosphere and oceans were formed: The granites at the surface of the continents were weathered and eroded into: Clay and Sand The clay & sand were carried by rivers to the oceans and deposited at the continental margins Burial of the clay and sand produced sedimentary rocks of shale and sandstone and

Mountain building along the continental margins melted the sedimentary rocks producing: Metamorphic rocks (partially melted) and Igneous rocks (completely melted) Rocky & Cordillera mountains Deformed sedimentary rocks Metamorphic rocks Igneous granites and basalts Deformation of Continents: Two Types

Rocky Mountains Deformation of Continents: Two Types 1. Mountain building: collision of two or more crustal plates 2. Continent warping creating major rivers that deposit erosional debris along the coast The history of the Oceanic Crust Result: Major rivers concentrate erosional debris in the oceans at the continental margins And plate collisions weld that debris back into the continent as mountains

Oceanic Crust: Basalt 5 miles thick Continuously Re-cycled Oceanic crust is melted as it is over-ridden by continental crust New oceanic crust is created in oceanic ridges Resulting in: Oceanic crust is 0 to 250 million years old Continental crust is 0 to 4.8 billion years old The North American Pacific Example

Earth’s Crust: Plates Pacific and North America

Earth’s Crust: Pacific and North American Plates Back to our route to New Mexico Pacific Plate under North America

Recent Rocky Mt Debris From: Roadside Geology of Texas How far did this river debris extend? “Recent River debris from the rising Rocky Mountains on top of older rocks A Closer Look on Our Way to New Mexico Cretaceous Limestones

Gravels & Sands Sands & Muds Recent Erosional Debris in Texas from the Mountains of New Mexico Recent Rising Rocky Mountains Recent Debris in New Mexico

Recent Debris in New Mexico Mountains shedding debris eastward Recent gravels & sands from rising Rocky Mts Pecos River Now the big picture in North America

Pacific Plate under North America Cordilleran & Rocky Mountains Hypothesis: Yellow: recent debris from the rising mountains that might have provided the access to the Americas for early humans migrating out of Siberia A quick look at the advent of humans Melting Continental Glacier Earth’s Crust: Plates Pacific and North America

Homo erectus Homo Antecessor/ mauritanicus Homo ergaster The Current Geological Record on the Advent of Humans Focus on the last 80,000 years Homo rhodesiensis Homo neanderthalensis Homo sapiens Times of Continental Glaciation: Northern Hemisphere

Missing Link? Uniquely human characteristics? 1. Reason 2. Conscience (right & wrong) 3. Adapt to any climate Time of Written World History Now, a look at the human migration route Last ice age

Rift Valleys Location of earliest human fossils Nile River

Possible Migration Route of Humans I t ’ s a 1 5, m i l e w a l k f r o m K e n y a t o A u s t i n, T e x a s ! ! ! Back to our journey to New Mexico

Appalachian Mountains Rocks of Central & West Texas Permian Rocks 260 million years old Permian rocks at the surface Thick Permian Reef Limestones Cretaceous Limestones The big Permian picture

Thickness Map: Permian Period Permian Basin

P B King; The Evolution of North America, 1959 A Cross Section of the Permian Basin Reefs The oil fields of the Permian Basin Permian Reef at the surface

The oil fields of the Permian Basin Delaware Basin Permian Basin Midland Basin Central Basin Platform Now, into New Mexico

Two drainage systems

Natural Resources Only copper and coal no tin or iron Little farming land But the geology is fantastic!

Rio Grande Rift (trench) Rocky Mountain Arch

Rio Grande Rift Rio Grande Rift near Alamogordo Alamogordo

/home.html#canyon What’s a rift or Graben? Rocky Mountain Arch

A Rift or Graben A Horst and Graben (rift) Structure Horst Graben (rift)

A Rift or Graben formed by Uplift, Stretching, & Collapse of the Crest Uplift, Stretching And then

Collapse of the Crest Horst Graben (rift)

Pacific Crust North American Crust Two Types of Rifts (Grabens ) Large Uplift Rio Grande Rift Salton Sea Rift Back to the Rio Grande Rift, NM

Present day surface Continental Crust Continental Crust Continental Crust Mantle rock (hot!) A cross section of the Rio Grande Rift Horst Rift Graben Trench Arch

From Roadside Geology of New Mexico, Chronic, Halka, 1987 The Rio Grande Rift (graben) Graben partially filled with debris from bounding horsts Western Horst Eastern Horst

Rio Grande Graben Eastern Horst Western Horst Focus: Eastern Horst Carlsbad to Roswell to Alamogordo

R i o G r a n d e R i f t Geologic Map: Southeast, NM Mountains on the East Horst Orange= non volcanic red = volcanic

R i o G r a n d e R i f t

R i o G r a n d e R i f t Sierra Blanca Igneous Mountains

Sierra Blanca Igneous Mountains Igneous Rocks and Rifts

Present day surface Continental Crust Continental Crust Continental Crust Mantle rock (hot!) Horst Graben Sierra Blanca Igneous Mountains

Sierra Blanca Mountains Volcanic Igneous rocks: Tertiary Age

Cloudcroft Geologic Map: Sacramento Mountains Alamagordo S a c r a m e n t o M o u n t a i n s

Cloudcroft Alamogordo Recent Rift Valley fill debris Down Rocks at the surface Permian Pennsylvanian Lower Paleozoic Pre-Cambrian Geologic Map: Sacramento Mountains Up How thick are these pre-Permian Rocks?

R e c e n t M o u n t a i n d e b r i s P e r m i a n a g e r o c k s P e n n s y l v a n i a n a g e r o c k s L o w e r P a l e o z o i c a g e r o c k s Pre-Cambrian continental foundation rocks Recent fill Now, going west across the Rio Grande Rift Cross Section of Eastern Horst

R i o G r a n d e R i f t Road Map: New Mexico

Crossing the Rio Grande Rift White Sands

Modified Space Photo

White Sands National Monument

Crossing the Rio Grande Rift San Andres Mountains

White Sands

ntains

San Andres Mountains Complex Up-thrown Fault Block in middle of Rio Grande Rift Involves Permian & Tertiary sedimentary rocks Contains rhyolites & granites (continental crust melted)

Present day surface Continental Crust Continental Crust Mantle rock (hot!) Horst Graben Continental Crust

Crossing the Rio Grande Rift The Western Horst San Andres Mountains Plains of St. Augustine

Datil-Mogollon Volcanic highlands Rio Grande Rift Western Horst

What is a Caldera? Answer: A “granitic”** volcano that has blown off its top **Granitic = melted continental crust

Caldera Explosion!!!! Collapse !!

The Yellowstone Caldera & Drainage Systems Grand Canyon Of the Yellowstone River Old Faithful

Yellowstone Volcanic Explosion Extent of Ash Deposits!!

Volcanic Explosions: Mt. St. Helens Tambora in Indonesia Tambora 36 cubic miles of ash!!!! Mt. St. Helens.25 cubic miles of ash!!! Largest known Volcanic explosion In human history!! Earth Volcano Volcanic Ash

Indonesia, Island of Sumbawa Indonesia

Indonesia Sumbawa Island Tambora Volcano Sumbawa Island

Rio Grande Rift Rocky Mountain Arch Colorado Plateau

Tambora Volcano, Indonesia Largest in Human History Tambora 36 cubic Miles! Mt St Helens.25 cubic Miles

Two of Three Volcanic Explosions at Yellowstone Huckleberry Ridge Volcanic Explosion 600 cubic miles of ash!!!!! Lava Creek Volcanic Explosion

Yellowstone Volcanic Explosion Calderas!!! Tambora 36 cubic miles Lava Creek & Huckleberry Ridge, 600 cubic miles!!! Mt. St. Helens

Yellowstone’s Three Explosion Calderas!!!

Yellowstone Explosion Calderas!!!

Caldera Complex volcanic interior

Arizona and California Next Week

Rio Grande Rift Rocky Mountain Arch Colorado Plateau