Discoveries In Warthan CreekDallas Chastain

Geology 3

Background/Research

• I made two trips to Warthan Creek: Once in October to study the area after rainfall, and again in November to observe the dried-up creek. • All rock and plant samples were photographed/collected

in and around the creek. • I took most rock samples home for further observation.• Rock/plant identification was done with the help of

Wikipedia and other digital sources.

About Warthan Creek

• Located In Coalinga, California.• Largely dry; eastern portion

seems to hold more water.• Runs several miles throughout

the outskirts of Coalinga.• Little variation in wildlife (more

on that later). • Dryness reveals water-based

erosion. • Likely formed at a faster rate

once the area became populated.

Earth’s Forces At Work• Following the creek led me

out of town, where I was able to observe these hills, which exhibit a nonconformity pattern. If you look at the hill on the right, you can see where the addition of sedimentary rock has eroded the metamorphic or igneous rock that was originally placed there. This would be the result of a long period of erosion caused by the sedimentary deposits.

Lateral Continuity• This separation in the ground, while

small, could be considered lateral continuity. The features on both sides of the gap are nearly identical, save for the gap separating them. My guess is that the gap was a result of the 1983 earthquake that destroyed much of Coalinga. The gap did indeed widen considerably, but it was in a restricted area that I had no access to.

• While this may not be an complete example of lateral continuity, this could be the process in its early stages, as water from the creek may continue to erode this area over time until there is a gap separating the two sides.

Plant Life: Geraea Canescens

• Geraea canescens, or the “Desert Sunflower”.

• Dicot (seed contains two embryonic leaves)

• “Geraea” is derived from the Greek geraios, or “old man”.

• Blooms after rainfall. • Few fossils have been

found, although the earliest dates back to about 50 million years ago.

Geraea Canescens:Classification • Kingdom: Plantae• Subkingdom: Tracheobionta • Superdivision: Spermatophyta• Division: Magnoliophyta• Class: Magnoliopsida• Subclass: Asteridae • Order: Asterales• Family: Asteraceae• Genus: Geraea • Species: Geraea Canescens

Plant Life: Hordeum Murinum

• Hordeum murinum, also known as “wall barley” or “false barley”. • Subspecies of grass. • Earliest fossil record dates

back 65 million years ago• Common source of

“foxtails”.

Hordeum Murinum: Classification • Kingdom: Plantae• Subkingdom: Tracheobionta• Superdivision: Spermatophyta • Division: Magnoliophyta • Class: Liliopsida• Subclass: Commelinidae• Order: Cyperales • Family: Poaceae• Genus: Hordeum L.• Species: Hordeum murinum L.• Subspecies: Hordeum murinum L. ssp. Glaucum Tzvelev

Animal Life: Theraphosidae

Animal life in Warthan Creek is few and far between. And with my luck, it’s no surprise that I ran into one of these! And yes, I did get that close! Let’s just say I’m lucky that the first picture turned out so well…

• Theraphosidae, better known as the “Tarantula”.

• 113 genera, and 897 species.• The largest specimen can

kills animals such as mice, lizards, and birds.

• Oldest fossil record dates back to the Triassic-200 to 250 million years ago.

• Primarily brown, although less common blue and even orange species have been discovered internationally.

Theraphosidae: Classification

• Kingdom: Animalia• Phylum: Arthropoda • Class: Arachnida • Order: Araneae• Superfamily: Theraphosoidea• Family: Theraphosidae

Rocks• This rock was somewhat tough

to identify, although I believe it to be sandstone.

• Sandstone is a sedimentary rock.

• Composition is primarily debris the size of sand(2 millimeters), more specifically quartz and feldspar.

• Can eliminate pollutants by storing water and other liquids.

• Color varies largely by what region it is found in.

Rocks Cont.

• This is a granite rock, which is used to create many objects that we come in contact with everyday.

• Granite is a very common igneous rock.

• Forms from crystallized magma beneath Earth’s surface.

• Main components are quartz and feldspar.

• Perhaps the most common rock found in Earth’s crust.

Rocks Cont.• I believe this rock is a sample of

quartzite, with its color affected by mineral impurities.

• Quartzite is a metamorphic rock that was originally sandstone. Tectonic compression is the cause for the transformation.

• Metamorphosis eliminates nearly every aspect of the sandstone.

• Comprised almost entirely of quartz and silica.

• Often used to create various silicone products.

Sources• http://www.geology.com/rocks• http://maps.google.com/maps?hl=en&tab=wl• http://plants.usda.gov/java/profile?symbol=GECA2• http://plants.usda.gov/java/profile?symbol=HOMUM• http://en.wikipedia.org/wiki/Geraea_canescens• http://en.wikipedia.org/wiki/Principle_of_lateral_continuity• http://en.wikipedia.org/wiki/Quartzite• http://en.wikipedia.org/wiki/Sandstone• http://en.wikipedia.org/wiki/Tarantula• http://en.wikipedia.org/wiki/Unconformity