Earth Science Flashcards
The process by which rocks are broken down into smaller rocks by natural events is called:
Weathering
What is deposition
Sediment, soil and rocks are added to landmass and form horizontal layers
Erosion is best described as
The movement of weathered materials from one place to another
What is chemical weathering?
caused by rain water reacting with the mineral grains in rocks to form new minerals (clay). These reactions occur particularly when the water is slightly acidic.
Shale is formed
From fine grains deposited in calm water
What rocks are often used as external walls of buildings?
Sandstone and Limestone
What rock is formed from living things?
Limestone (shells and bones compressed)
What are 4 metamorphic rocks?
Marble, Quartzite, Slate, Gneiss
What are 5 igneous rocks?
Andesite, Basalt, Dacite, Obsidian, Pumice
What are 3 sedimentary rocks?
Sandstone, Limestone, and Shale
Rocks transformed from one type of rock into another by heat or large amounts of pressure are called
Metamorphic rocks
What are sedimentary rocks?
Sedimentary rocks are formed from pre-existing rocks or pieces of once-living organisms. They form from deposits that accumulate on the Earth’s surface. Sedimentary rocks often have distinctive layering or bedding.
Rocks which form from volcanic lava flows are classified as
Igneous rocks
A palaeontologist studies
Fossils
What are some fossil items?
Dinosaur footprints, Impressions of the skin of an ancient fish, An impression of the leaf of an ancient plant, Dinosaur bones
The half life of an element
The time it takes for half the radioactive atoms to decay
Radiometric dating is used to determine
The absolute age of rocks
A dinosaur footprint is an example of a
Trace fossil
What does ectothermic mean
Body temperature that fluctuates (varies) with the environment
Describe two causes of weathering
Wind, Water, Acid rain
What is the difference between sandstone and conglomerate rock?
Sandstone is pure sand, Conglomerate contains pebbles
Give uses for 3 sedimentary rocks
Limestone is used to make cement, Coal is used for fuel, Sandstone and Basalt are used for buildings
Give two factors that affect the formation of metamorphic rocks
Type of rock, Pressure, Amount of heat
Describe two ways that fossils may be formed
Deposition, Petrification (replaces original material by filling pore spaces with minerals)
Why may we have not found a fossil of every living creature that has existed on earth?
Fossils might’ve broken down, Too deep to be found, Has to be particular conditions for fossils to form
How might we find fossil remains of an organism that include soft tissue parts as well as hard structures like wood and bone?
Sudden Flood/Burial
How could an asteroid wipe out all the dinosaurs if it hit only a very small section (overall) of the Earth’s surface
Because of the dust it creates
What is unique about preserved fossils?
Preserved fossils are plants or animals that still have their inner and outer flesh intact
What type of fossil’s bone is replaced by minerals, forming a replica pf the bone that was once there?
Mold fossil
What can fossils tell us about past animals and life?
Information about the past environment, Where animals came from, What animals from the past looked like
