By Kristin Lynch

•This is an igneous rock.•Granite is cooled intrusively (beneath the surface of the Earth).•The composition of granite is Sialicwith coarse grains and flecks of quartz and potassium feldspar.

I was fairly sure this rock was granite, but decided to break it open with a hammer and see the inside to be sure. Once broken, I could see the signature salt-and-pepper look of granite along with the shimmery flecks of quartz and potassium feldspar!

I found this chunk of granite rock in a field in Hanford, California, near my workplace. There are many fields around the area and a variety of rocks can be found there. Yosemite National Park’s bedrock is formed mostly of granite. There are many formations (El Capitan, Cathedral Rocks, etc.) that are formed from this granite (Time). This chunk of granite is fairly large and I believe most likely came down from the Yosemite area.

Studying this rock in low light, one can see the few shimmery flecks in the surface of the rock. The texture of the rock is not gritty, like the sedimentary rock sandstone, but instead is extremely smooth. I assumed this may be either from long exposure to wind or water. Some of the layers in the rock look like they are etched in and possibly disintegrating. This leads me to the conclusion that some layers of the sediment were not held together as strongly as the others due to the material they are made up of.

I first identified this rock as a sedimentary rock, identified by its several strata from compressed layers of sediment and brownish-gray color. It is also very smooth in texture, most likely from water. Further identified, I believe this rock may be basalt.

This rock is extremely hard and would not break with a hammer. I had to use a sledge hammer to break it open. Once broken open, the layers that were so apparent on the outside of the rock became almost non-existent on the inside. The entire rock is extremely fine-grained and the inside is a dark grey and very shimmery. Because the shimmers are so many and so tiny, I would guess that they may be flecks of mica. There are flecks of mica in basalt. I also did the scratch test with this rock, and was not able to scratch it with a nail. Using a knife, I was able to scratch thin, shallow lines into the surface of the rock. Further testing with vinegar, I dropped a couple of drops onto the exterior surface, as well as the inside, and nothing happened. This is common for basalt rocks, unless there are patches or bands of calcite, which there weren’t in my rock.

Outward appearance, this rock looks sedimentary, but the inside makes me think metamorphic. Due to the physical properties and the tests that I did on this rock, I concluded that this rock is the igneous rock, basalt.

I found this intriguing and perplexing rock on a country road in Hanford, California while out taking photographs. If I correctly identified this rock as basalt, then it may be from the Lovejoy basalt, the largest eruptive unit in California. The Lovejoy flowed to the Sacramento Valley, which is very near to our Central Valley, where Hanford, California is located (A Mantle Plume).

I deduced that this rock was marble due to the color, shape, shining flecks, and scratch and vinegar tests. Marble is a metamorphic rock that was once limestone. Limestone is a sedimentary rock, but once exposed to high heat and pressure underground, it morphs into marble (Neighborhood Rocks: White Marble).

This rock is white with semi-translucent high-shine flecks in it. In this piece, there are a small amount of gray streaks and many medium-sized crystals that glitter when light is shined on it. I scratched this rock with a knife and white powder came off easily. I also tried the white vinegar test, which produced slight bubbling.

I found this chunk of marble in another field between my house and work in Hanford, California. It really is a beautiful rock and it stood out in the field because of its stark white color and reflective flecks throughout the rock. I deduced that this rock probably came from someone’s garden/landscaping project because, after researching, I found that there aren’t any large marble areas around here. Marble chips are sold at home improvement stores and nurseries and are commonly found in landscaping.

Kingdom: Animalia (animals)

Phylum: Anthropoda (crustaceans, spiders, insects, and relatives)

Class: Arachnida (arachnids)

Order: Solpugida ( solpugids and sun spiders) (ADW)

Sun spiders are otherwise known as camel spiders or wind scorpions. The names come from the color, humped back, or speed of the spider-like insect. These creatures are commonly found in the desert but they do not like the sun. It looks like a scorpion mixed with a spider, but it is not a spider. It uses its front legs (which are sticky) to grab its prey and pull it towards its pincers, which work like tiny saws to liquefy it before consuming it. They are not venomous and usually go near humans merely to stand in the shade of their shadow (Cranshaw).This sun spider was found in Hanford,

CA, in a home improvement store. Since these insects are desert dwellers,

I’m guessing this guy hitched a ride from one of the seamen that came back

from Navy business in Fallon, CA.

Kingdom: Plantae

Subkingdom: Tracheobionta

Division: Magnoliophyta

Class: Magnoliopsida

Subclass: Magnoliidae

Order: Papaverales

Family: Papaveraceae

Genus: Eschscholzia

Species: Eschscholzia Californica

(Biogeography)

The California Poppy is the state flower for California and grows wild throughout the state. They flourish on hillsides and in grassy, sandy, or rocky areas that are dry. They grow primarily in Southern California, but are also common up the coast through Oregon and into Washington, as well as in Nevada, New Mexico, and the northern part of Baja, Mexico (Biogeography).

This poppy is growing in Hanford, CA, located in the Central Valley,

which is a very dry area.

The Kings River that runs through Kings County, Fresno County, and Kings Canyon National Park in California begins in the Sierra Nevada. Some parts of the river are dammed and much of the river is utilized for its agricultural/irrigation purposes. It has also carved one of the deepest canyons in North America, beginning in the Sierra Nevada and dropping more than 13,000ft to the upper limit to the Pine Flat Reservoir! (Friends of the River)

This is a picture of what the part of Kings River looks like that runs near Lemoore, Ca. It is commonly utilized during the warmer months for rafting, floating, boating, and fishing. This part of the river is far from the Middle and North Forks that are more commonly known for its rafting opportunities.

References

A mantle plume beneath California? The mid-Miocene Lovejoy flood basalt, northern California . (n.d.). Geological Society of America Special Papers . Retrieved November 15, 2011, from http://specialpapers.gsapubs.org/content/438/551.abstract

ADW: Eremobatidae: Classification. (n.d.). Animal Diversity Web. Retrieved November 18, 2011, from http://animaldiversity.ummz.umich.edu/site/accounts/classification/path/Eremobatidae.html#Eremobatidae

Biogeography of the California Poppy. (n.d.). redirect. Retrieved November 18, from http://bss.sfsu.edu/holzman/courses/Fall02%20projects/calpoppy.html

Cranshaw, W. (n.d.). Sunspiders (Windscorpions). Colorado State University Extension. Retrieved November 18, 2011, from http://www.ext.colostate.edu/pubs/insect/05589.html

Friends of the River: California Rivers - Kings River. (n.d.). Friends of the River: Home Preserve Restore Sustain California Rivers. Retrieved November 18, 2011, from http://www.friendsoftheriver.org/site/PageServer?pagename=FORCalRiversKingsRiver

Neighborhood Rocks: Gray Slate. (n.d.). Salt the Sandbox: Home Page. Retrieved November 18, 2011, from http://saltthesandbox.org/rocks/grayslate.htm

Neighborhood Rocks: Scoria Basalt. (n.d.). Salt the Sandbox: Home Page. Retrieved November 12, 2011, from http://saltthesandbox.org/rocks/basalt.htm

Neighborhood Rocks: White Marble. (n.d.). Salt the Sandbox: Home Page. Retrieved November 12, 2011, from http://saltthesandbox.org/rocks/whitemarble.htm#HowFormed

claystone (geology) -- Britannica Online Encyclopedia. (n.d.). Encyclopedia - Britannica Online Encyclopedia. Retrieved December 1, 2011, from http://www.britannica.com/EBchecked/topic/120751/claystone

time, m. C., & ago, a. f. (n.d.). CVO Menu - America's Volcanic Past - Yosemite. USGS Cascades Volcano Observatory (CVO). Retrieved December 1, 2011, from http://vulcan.wr.usgs.gov/LivingWith/VolcanicPast/Places/volcanic_past_yosemite.html