Clastic Sedimentary Rocks
Chemical Sedimentary Rocks
Sedimentary Structures
Volcano/Magma
Misc
100
What is the definition of clastic sedimentary rock?
rocks made up of sediments clasts of other older rock
100
What is an example of a chemically weathered rock
Limestone, Chert, Evaporites, or Coal
100
What is this?
Mudcracks
100
What type of volcano is this?
Shield Volcano
100
What is the smallest and largest pyroclast formed from a volcano
Ash and Blocks/Bombs
200
What sets mechanical weathering apart from chemical weathering?
Mechanical weathering is making new rocks from preexisting rocks by breaking them down but not altering their original composition.
200
Give an example of a chemical sed rock that forms by non-biologic chemical processes
Evaporites or chert
200
What is this?
Ripples
200
what kind of lava is this?
A'a
200
Name the texture that occurs when cooling rate is especially fast
aphanitic texture
300
What kind of environment would you expect to find well rounded pebble sized stones that are well sorted?
High energy i.e. a fast moving river
300
Give an example of a chemical sed rock that forms by biologic processes
Coal, Limestone, or chert
300
Which direction was the current flowing?
Right
300
Define a pyroclastic flow
A fast-moving, extremely hot current of volcanic ash, gases, and rock fragments that rushes down a volcano's slopes during an explosive eruption.
300
What is the relationship between crystal size and cooling rate?
Faster the cooling rate the smaller the crystal size
400
List the following in order of largest to smallest grain size
(sand, clay, silt, boulder, and pebble
Boulder, Pebble, Sand, Silt, Clay
400
Explain each of the three processes of chemical weathering
Dissolution: mineral dissolved by water and/or acid
Oxidation: Rusting, when iron atoms in minerals bond with oxygen
Hydrolysis: Water or acid reacts with feldspar
minerals to form soft clay minerals and dissolved ions
400
When would you be able to tell that cross-bedding was formed by wind instead of water
When the size of the bed exceeds 1m in thickness
400
What type of eruption would you expect from a volcano with viscous magma, high gas content, and containing a lots of silica?
Explosive or violent eruption
400
Given the list of minerals and silica compositions what order will they begin to melt in:
Mineral A: 39% Silica
Mineral B: 90% Silica
Mineral C: 12% Silica
B, A, C
500
What are the 5 process of mechanical weathering?
Frost wedging, Salt wedging, Jointing due to decompression, biological agents, and abrasion
500
Name the 2 naturally occurring acids discussed in class and how they form
Carbonic Acid: CO2 + H2O
Sulfuric Acid: SO2 + H2O
500
What are the 8 sed structures?
Ripples, Dunes, Cross-bedding, Imbrication, Graded bedding, Mud cracks, Scour marks, Trace fossils
500
List each of the 4 volcanoes talked about in class and their respective eruption style
Shield: Effusive
Cinder Cone: Erupt pyroclasts that build up its cone
Stratovolcano: alternating effusive and explosive
Caldera: Explosive
500
What kind of rock type would you expect to find if you had a mafic lava that was allowed to cool very slow?
Gabbro