The document summarizes geological features and flora and fauna found along the Cold Creek Trail near Lake Tahoe, California. It describes the trail's location and methodology used for the study. Key points include that the Sierra Nevada mountains formed from uplift starting in the Late Cretaceous period. Lake Tahoe was created by block faulting around 2-3 million years ago. Rocks in the area include granite, basalt, schist, and quartz. Plants like mountain mule ears, rosy sedum, and snow plant grow in the region. Black bears and introduced dogs have also been spotted. High meadows form over time as sediment fills bodies of water.

1. Cold Creek Trail & High
Meadow
Lake Tahoe, California
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Patrick Rulo
Professor Mark Lawler
Geology 103
June 18,2015
Photo by P. Rulo
High Meadow

2. Location
Cold Creek Trail is located in South Lake Tahoe and
is a popular mountain biking trail. The trail starts up a
moderate grade through a pine forest and goes
through different zones as elevation changes. At the
top of the trail is High Meadow and then the trail
follows Cold Creek back to the start.
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3. Methodology
• During May and June I hiked and rode Cold
Creek trail a couple of times, taking pictures and
collecting samples, while familiarizing myself with
the area.
• Plant ID was performed with Wildflowers of the
Tahoe Sierra
• Rock ID was performed with Rocks & Minerals
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4. 4
Off to Collect Samples on
Cold Creek Trail
Photo P. Rulo Collection

5. Overview of Geological History of Lake
Tahoe & Sierra Nevada Mountain Range.
• According to the Geological Society of America,
evidence suggest that the Sierra Nevada are a result
of an uplift from the crust becoming thicker during the
Late Cretaceous or Early Cenozoic Period.(GSA)
• A rain shadow east of the Sierra Nevada has been
around since the middle Miocene Period. (GSA)
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6. Overview of Geological History of Lake
Tahoe & Sierra Nevada Mountain Range.
• Lake Tahoe Basin was the result of block faulting
2-3 million years ago. (USGS)
• Around 2.5 years ago glaciation eroded many
parts of the Sierra Nevada. (Wikipedia)
• Uplifting of the Sierra Nevada is on ongoing
process that is still occurring.

7. Rocks found around Cold
Creek Trail & Lake Tahoe
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Photo by P. Rulo

8. Rocks found around Cold
Creek Trail & Lake Tahoe
• The oldest rocks in the Sierra Nevada are
metamorphic rocks such as schists and
slates.(wikipedia)
• Granite was formed as early as the Jurassic Period.
• Much of the course soil and rocks are a result of
glaciation and erosion.
• Quartz is common in surface rocks and igneous
rocks such as granite.
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9. Granite
Igneous Rock
Sialic- Silica Rich
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10. Basalt
Igneous Rock
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11. Schist
Metamorphic Rock
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12. Milky Quartz
Silicate
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13. Rose Quartz
Silicate
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14. Flora & Fauna
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15. Mountain Mule Ears
Wythea mollis
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Photo By P.Rulo

16. Mountain Mule Ears
Wythea mollis
• Member of the Sunflower Family
• Common in Lake Tahoe from 6250’ to 8500
• Broad leaves covered with white silky hairs to
lessen evaporation.
• One plant can be reproduced if only one flower is
pollinated.
• Range:Sierra Nevada to Oregon.
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17. Rosy Sedum
Sedum roseum
17 Photo by P.Rulo

18. Rosy Sedum
Sedum roseum
• Member of Stonecrop family
• Found in Rocky areas
• Range in Tahoe: 7,000’ to 10,500’
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19. Snow Plant
Sarcodes sanguinea
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20. Snow Plant
Sarcodes sanguinea
• Member of the Wintergreen Family
• Resembles an asparagus and is edible, although,
it is protected.
• Does not photosynthesize, but is mycotrophic.
• Found on forest floors up to 8,000’.
• Appears in spring in shaded areas.
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21. Black Bear
Ursus Americanus
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Photo from Google

22. Black Bear
Ursus Americanus
• The American Black Bear is the most common bear species in the
world.
• Despite being called black bears, they can have brown, blonde and
cinnamon colored coats.
• Black bears are omnivorous.
• Bears live in various habitats and can be found from elevations at
1,300’ to 9,800’.
• Black Bears are highly efficient at hibernating through the lean
months of the year.
• Bears live from 18 to 23 years.
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23. Invasive Species
Canis Familiarus Daisy
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24. Invasive Species
Canis Familiarus Daisy
• Introduced to Tahoe in 2012.
• Member of Canis rulo family.
• Likes to run in packs with mountain bikes.
• Omnivore, prefers kibble and cookies.
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25. High Meadow
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26. High Meadow and how
meadows form
• Meadows form when sediment fills lakes and ponds and
over a long period of time,water becomes earth. Grasses
and other sun dependent plants form the meadow. An
example of this process is Mirror Lake in Yosemite Valley.
• Meadows serve as a wetland for the mountains by filtering
water.
• As time goes by, the meadow is invaded by various pine
trees.
• The pine trees eventually block the sunlight making the
meadow disappear.
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27. High Meadow
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28. High Meadow
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29. High Meadow
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30. Cold Creek Trail
Riparian Area
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31. Cold Creek
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32. Cold Creek
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33. Cold Creek
• Boulders have the appearance of being pushed
into a pile, like a moraine at the snout of a glacier
that I have seen from mountaineering.
• This appears to be evidence of glaciation from
the last ice age, when the Sierra Nevada’s had
significant glaciers.
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34. Conclusion
• Geologic Processes have formed the mountains
that we love and those processes will constantly
change them.
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35. References
• Baker, Elna, An Island Called California, University of California
Press, Berkeley, 1972
• Blackwell, Laird R. Wildflowers of the Tahoe Sierra, Lone Pine
Publishing, 1997
• Unknown, Rocks & Minerals, St Martins Press,1973
• wikipedia.org Black Bear & Geology of the Sierra Nevada
• USGS.Gov Lake Tahoe Geology overview
• geology.gsapubs.org Henry, Christopher,Uplift of the Sierra
Nevada, Viewed on June 19, 2015
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