- Las Positas College
- Geology Program
- Display case 2420
Geology Program
Display case outside 2420
The skull in the display case is 1/10 size. Actual size of a real skull of this animal features 6 inch teeth and is 4 1/2 feet from back of skull to front of jaw. It is a Tyrannosaurus Rex, T. Rex for short.
- Whelks are carniverous marine gastropods that can drill through the shells of potential
prey. The live in the midlittoral zone along side barnacles and anemones. There is
also an abalone shell on this table.
- For more information http://animals.howstuffworks.com/marine-life/whelk-info.htm
- Chambered nautilus are cephalopods like the octopus and cuttlefish. They are related to an ancient group of species, the ammonites( see below #7). Chambered nautilus detect food by smelling the ocean currents.
- Gypsum is a common mineral, chemical formula CaSO4; Calcium Sulfate. The sheetrock
in your house is made of gypsum because it is light, strong, and won't burn.Gypsum
is mined in California in several desert locations. Gypsum is also used to correct
soil pH and improve soil texture for crops.
- For more information http://www.geo.msu.edu/geogmich/gypsummining.html
- Halite is common table salt. Halite is composed of sodium and chlorine atoms arranged
in a molecular structure that forms natural cubes. Because halite is a lighter than
average mineral, it tends to move upward in rock formations, creating 'salt domes'.
Halite is often mined at the seashore by creating salt retention ponds.
- For more information http://www.minerals.net/mineral/halite.aspx
- Quartz is a hard, glassy mineral, common in many rocks including granite. Quartz is
used in industry for guages, heat lamps, prisms and lenses. Some forms such as amethyst
and tiger eye are commonly used in jewelry. Quartz is estimated to comprise 12% of
the Earth's crust.
- For more information http://www.minerals.net/mineral/quartz.aspx
- Brachiopods are a marine bivalve that are also called lampshells.They wre the most
abundant and diverse invertebrates of the Paleozoic.They have had a wide variety of
shell shapes over the eons, and continue to live today, even though most people have
never heard of them. They are truly a living fossil.
- For more information http://www.ucmp.berkeley.edu/brachiopoda/brachiopoda.html
- Ammonites are the earliest cephalopods, first found in the Cambrian. They ranged in
size from less than an inch across to over 4 feet across. They swam much like a chambered
nautilus does today. There have been hundreds of different ammonite species, sadly
all are extinct today.
- For more information http://www.ucmp.berkeley.edu/taxa/inverts/mollusca/cephalopoda.php
- Trilobites lived only in the Paleozoic. They were marine creatures that lived on the
sea floor, similar to the horse shoe crab of today. They had a hard carapace similar
to the horse shoe crab of today. They burrowed in the soft sediments seeking anything
small and edible.They molted, shedding their shells as they grew, which probably helped
give them such a large representation in the fossil record; each animal might leave
behind 20 shells.
- For more information http://www.ucmp.berkeley.edu/arthropoda/trilobita/trilobita.html
- WHAT IS NUMBER 9? Email me your answer cedson@laspositascollege.edu Could be extra credit if you figure it out....Here are a few hints. These creatures live in colonies up to two feet across.Some of the species have been around for over 500 million years. They are still found in oceans today but are most common in tropical seas.
- Sharks are a great design- they have been successfully cruising the oceans for over
420 million years. The greatest threat to living shark species is over- fishing. Sharks
mature late and reproduce on a small scale, plus their world wide numbers are not
known. Megalodon is an extinct shark species that was the largest known. Teeth of
shark species through geologic time have varied from tiny to almost 6 inches long.
Megalodon was over 60 feet long!
- For more information on the largest shark that ever lived go to http://www.flmnh.ufl.edu/fish/sharks/fossils/megalodon.html
- Sand dollars are frisbee shaped shells that are purple while the animal is alive.
Sand dollars eat detritus in the soft marine sediments in the lower tidal zone. They
are closely related to the spiny sea urchin, and move slowly across the sand the same
way.
- For more information http://animals.howstuffworks.com/marine-life/sand-dollar-info.htm
- Sea scorpions are an extinct species of aquatic creatures that lived in both fresh
and salt water. They resembled land scorpions in some ways, but the largest marine
varieties were over 7 feet long! These were among the largest marine predators during
the Ordovician and Devonian time periods.Called Eurypterids, these animals died out
in the Permian extinction.
- For more information http://www.ucmp.berkeley.edu/arthropoda/chelicerata/eurypterida.html
- Geodes are also called 'Thunder Eggs'. They are spherical rock formations that are
sedimentary in origin. Most have layers of quartz or calcite crystals in their hollow
centers, forming a beautiful inner sphere. One must break or cut them in half to find
out what is inside.
- For more information http://www.igsb.uiowa.edu/browse/geodes/geodes.htm
- Phyllite is a slaty metamorphic rock with sheen. It is commonly found in places like
the Appalachian mountians. If you smash mudstone into slate and continue to smash
it, the grains will become more aligned and the sheen characteristic will develop.
If the rock is flattened even more it may progress to schist, where the sheen becomes
actual spangles or sparkles of mica grains.
- For more information http://geology.about.com/od/rocks/ig/metrockindex/rocpicphyllite.htm
- Glossopteris is an extinct plant group, with 'tongue shaped' leaves, hence the name.
It was common in the Permian, and died out completely in the Permian Extinction.
- For more information http://www.ucmp.berkeley.edu/seedplants/pteridosperms/glossopterids.html
- Horn coral are an extinct group that ranged from a centimeter to a meter in length!
They were solitary not colonial in most cases.
- For more information http://www.ucmp.berkeley.edu/cnidaria/anthozoafr.html
- Sandstone is a common California rock, made of sand particles glued together by chemical
cement like calcite or quartz, and compaction. Cliffs in California made of sandstone
are often very soft and suffer lots of landslides and mass wasting during winter storms.
Sandstone can be banded in color like this sample, and be called Rainbow sandstone.
- For more information on the beautiful formations sandstone can form http://www.artinnaturephotography.com/wordpress/2012/the-navajo-rainbow-sandstone-slot-canyon/
- Fuchite mica is a sparkly green form of mica. It looks 'fake' to many students but
is in fact a naturally occuring mineral. This form of mica is very soft, and can be
scratched with your fingernail.
- For more information http://www.galleries.com/Fuchsite
- Pumice is volcanic foam; it actually floats in water. Near Crater Lake is a huge area
covered in Pumice called the Pumice Plain. Pumice can come in a number of colors;
red, grey, tan, cream and brown.
- For more information http://geology.com/rocks/pumice.shtml
- Pyrite is iron sulfide and is commonly called Fool's gold. It is harder than gold,
and has a grey streak. Pyrite forms in metamorphic processes where pressure is changing
mudstone into slate.
- For more information http://geology.com/minerals/pyrite.shtml
- This granite stream cobble is an example of spheroidal weathering and abrasion. Its
rounded shape is due to saltation in the stream bed, gradually wearing away all the
corners. The eroded corners become the light colored sand so common on California
beaches.
- For more information http://en.wikipedia.org/wiki/Granite
For more details on specific varieties email me (see above)
For more information please contact:
Ruth Hanna
Geology Faculty
Office 1829 / 1824
(925) 424-1319
rhanna@laspositascollege.edu
Christina Flora
Geology Lab Technician
Room 1824
(925) 424-1336
cflora@laspositascollege.edu