lake tahoe basin
TRANSCRIPT
T H E G E O L O G Y O F T H E L A K E TA H O E B A S I N
F I E L D A S S I G N M E N T P R O J E C T B Y J O H N Q U I N N
G E O L O G Y 1 0 3
Satellite photo courtesy of NASA
O B S E R VAT I O N S
• In June of 2014 I made two observation trips in the South Lake Tahoe area.
• One observation trip was made along the southern edge of Lake Tahoe on the Rubicon Trail between D.L. Bliss State Park and Emerald Bay.
• One observation trip was made from the Eagle Falls trailhead to Eagle Lake in Desolation Wilderness.
• I was able to observe numerous rocks and rock formations, several plants, bushes, trees, and few birds and animals.
• All observations and findings were made by me.
• All photos take were by Hailey Quinn unless otherwise noted.
F O R M AT I O N O F T H E TA H O E B A S I N
1. Plate Movement
2. Volcanic Activity
3. Glaciation
4. Glacier Melt
H O W W A S L A K E TA H O E F O R M E D ?
“ A B O U T 2 4 M I L L I O N Y E A R S A G O T H E S I E R R A N E VA D A B L O C K
WA S F O R M E D B Y T R E M E N D O U S U P L I F T I N G . T W O P R I N C I PA L
FA U LT S E V O LV E D : T H E E A S T E R N M A R G I N C R E AT E D T H E C A R S O N
R A N G E , W H I L E T H E S I E R R A N E VA D A D E V E L O P E D O N T H E
W E S T E R N S I D E . F R O M T H E " U P T H R O W N " FA U LT B L O C K S , T H E
H I G H E S T P E A K S I N T H E R E G I O N O R I G I N AT E D W H I L E T H E ‘ D O W N
T H R O W N ’ B L O C K S A N K C R E AT I N G A L A R G E VA L L E Y. ”
- ( U S D A N . D . ) !
U S G S . M AY 2 1 , 2 0 1 4
H O W W A S L A K E TA H O E F O R M E D ?
“ L AVA F L O W I N G F R O M M T. P L U T O O N T H E N O R T H S H O R E , T H E N F O R M E D A B A R R I E R O R
D A M A C R O S S T H E B A S I N ' S A N C E S T R A L O U T L E T, T H E
T R U C K E E R I V E R . WAT E R F R O M S N O W FA L L A N D S T R E A M S
F L O W I N T O T H E B A S I N , G R A D U A L LY C R E AT I N G A L A K E
S E V E R A L H U N D R E D F E E T H I G H E R T H A N T H E P R E S E N T L A K E . E V E N T U A L LY A N E W
O U T L E T WA S E R O D E D F R O M T H E L AVA D A M C R E AT I N G T H E P R E S E N T PAT H O F T H E L O W E R
T R U C K E E R I V E R . ” - ( U S D A N . D . )
Seasonal stream running into
the Lake Tahoe Basin
H O W W A S L A K E TA H O E F O R M E D ?
“ F O L L O W I N G T H E FA U LT I N G A N D V O L C A N I C P E R I O D O F T H E B A S I N ,
A N I C E A G E D E V E L O P E D . H U G E G L A C I E R S F O R M E D A N D M O V E D
D O W N T H E V- S H A P E D C A N Y O N S O N T H E W E S T E R N S I D E O F T H E L A K E . T H E S E G L A C I E R S S C O U R E D AWAY L O O S E R O C K A N D R E S H A P E D T H E C A N Y O N S I N T O B R O A D U - S H A P E D VA L L E Y S . T H E R O C K A N D G R AV E L
L E F T B E H I N D AT T H E S I D E S A N D E N D O F T H E S E M E LT I N G G L A C I E R S A R E C A L L E D M O R A I N E S . A S T H E S E
G L A C I E R S M E LT E D AWAY, T H E Y A L S O L E F T B E H I N D B R I L L I A N T
B AY S , J A G G E D P E A K S , G L A C I A L P O L I S H E D R I D G E S A N D C R Y S TA L
C L E A R L A K E S . ” - ( U S D A N . D . )
E V I D E N C E O F G L A C I AT I O N
I N T H E A R E A .
L A R G E G R A N I T E S L A B P O L I S H E D F L A T B Y G L A C I A T I O N
S E D I M E N TA R Y R O C K
• Breccia
• Piled up pieces of broken rock held together by quartz and compressed together.
S E D I M E N TA R Y R O C K
• Sandstone
• Eroded rock particles into sand.
• The sand is accumulated and compressed.
S U G A R P I N E T R E E
• P I N U S L A M B E R T I A N A !
• M E M B E R O F T H E W H I T E P I N E G R O U P !
• K N O W N F O R I T S L O N G D O W N WA R D G R O W I N G C O N E S
L A R G E M A N Z A N I TA F I E L D
• Manzanita (species)
• Arctostahpylos (genus)
• “There are 106 species of manzanita, 95 of which are found in the Mediterranean climate and colder mountainous regions of California, ranging from ground-hugging coastal and mountain species to small trees up to 20 feet (6m) tall. Manzanitas bloom in the winter to early spring and carry berries in spring and summer.[1] The berries and flowers of most species are edible.” (wiki, june. 8. 2014)
R E F E R E N C E S
• Tahoe Adventure Sports (2000). D.L. Bliss Rubicon Trail. Retrieved from http://www.tahoeadventuresports.com/hikeindex/west/rubiconmapandprofile.htm
• USDA (no date). Geology of the Lake Tahoe Basin. Retrieved from http://www.fs.usda.gov/detail/ltbmu/learning/?cid=stelprdb5109570
• USGS (May 22, 2014). Lake Tahoe Faults, Shaded Relief Map. Retrieved from http://gallery.usgs.gov/photos/05_21_2012_dhx3Bnm00U_05_21_2012_1#.U6TL2BboYb2
• en.wikipedia (May 3, 2014). Pinus Lambertiana Retrieved from http://en.wikipedia.org/wiki/Pinus_lambertiana
• en.wikipedia (June 8, 2014). Manzanita Retrieved from http://en.wikipedia.org/wiki/Manzanita