The Dynamic Earth
The Rock Cycle
History of the Earth
Black Science History
Nature of Science
100
The heat from the Earth's core conducts to the mantle to become hot, but the heating is uneven. This causes the rock in the mantle to churn, rising up and falling down in the mantle.
What kind of currents are these?
Convection Currents
100
Igneous rock can be formed in one of two ways. When molten rock breaches the surface, the lava cools to form these kinds of igneous rock, like obsidian.
What kind of igneous rock is being described above?
Extrusive Igneous Rock
100
Very rarely, remains of organisms can be preserved if they are quickly buried after death by sand or mud. As the organism decays, hard tissue like bones can be replaced by hardened sediment, preserving their shape and creating these artifacts of their existence.
What kind of artifact is being described above?
Fossils
100
Dr. Mae Jemison, the first black woman in space, flew on the Endeavor on September 12, 1992. This kind of craft has enabled scientists like Jemison to regularly conduct experiments in space and safely return home on the same craft that brought them up.
What kind of space craft did Mae Jemison take?
Space Shuttle
100
Fill in the Blank: The _____ of Plate Tectonics is an EXPLANATION of WHY there are so many earthquakes on the West Coast of the US, WHY volcanic island chains like Hawaii exist, and WHY entire mountain ranges exist like the Himalayas. Of course, this explanation required lots of different kinds evidence from scientists to support it.
Scientific Theory
200
No scientist has ever observed the layers of the Earth directly. Our knowledge of Earth's structure is based on collecting and analyzing data indirectly, using waves caused by earthquakes.
What kinds of waves are these?
Seismic Waves
200
Rock that gets buried deeper into the Earth gets closer to the mantle, experiencing increased heat from below and increased pressure from the above. These two key forces create this chemically distinct rock from other types of rock.
Which kind of rock is made from high heat and pressure?
Metamorphic Rock
200
These kinds of rocks are formed by stacking sheets of sediment on top of one another. Over millions of years, it hardens, creating a timeline of events that scientists use to learn more about Earth's history and changes.
Which type of rock is being described above?
Sedimentary Rocks
200
Thanks to the mathematician Gladys Brown West (1930 - 2026), we now understand the Earth is not a perfect sphere, but is actually wider at the equator due to this movement by the Earth. This discovery was used to improve the effectiveness of Global Position Systems (GPS).
What movement of the Earth causes it to be wider at the equator?
The Earth's Rotation
200
Fill in the Blank: The _____ of Superposition is a RULE that states in WHAT order rock layers are formed as long as they remain undisturbed. This RULE is supported by lots of evidence like certain fossils like trilobites frequently being found deeper than other fossils like giant ammonites.
Scientific Law/Principle
300
When two plates collide, the denser plate always sinks below the other. This phenomenon most clearly occurs when an oceanic plate collides and sinks below a continental plate, and is a major cause for the creation of volcanic mountain ranges.
What is it called when a dense tectonic plate slides under another plate?
Subduction
300
Water is a force that cuts rock and spreads it out, but it does so in two ways. One way is the physical trauma of constantly hitting it or chipping away for millions of years. The other way is represented by carbonic acid, which is made when water in the atmosphere mixes with carbon dioxide and comes down as acid rain.
What kind of weathering is caused by carbonic acid?
Chemical Weathering
300
According to the Principle of Cross-Cutting Relationships, which feature is the youngest?
Intrusion T
300
Dr. Maguerite Williams, the first black woman geologist in the US, studied the Anacostia Drainage Basin in Maryland. Her work was among the first to investigate the impact of deforestation and agriculture on increasing the rate of this process in the rock cycle.
Which rock cycle process is increased by deforestation and agriculture?
Erosion
300
Fill in the Blank: Models are only as effective as the data used to make them. The potential of a model is also based on whether it can be modified or improved upon when new ____ is discovered.
Evidence/Data/Information
400
The Atlantic Ocean is getting bigger! As South America and Africa move away from each other, the seafloor spreads at this type of plate boundary. We also know this because of the Mid Atlantic Ridge, an enormous mountain chain of volcanic rock that stretches across the Atlantic Ocean from the North to the South.
What kind of boundary is depicted above?
Divergent Boundary
400
The Rock Cycle isn't a perfect circle, but there is an order to the chaos. For instance, sedimentary rock forms from other rocks, but not before those other rocks are broken down and moved by these processes.
Which two processes MUST occur before sedimentary rock is made?
Weathering and Erosion
400
Relative dating of rock layers and fossils is not very precise. Scientists eventually discovered that rocks and organic tissue contain small amounts of these radioactive atoms that decay at a consistent rate called a Half-Life. They act as clocks to help scientists measure in years how long ago a fossil or rock was formed.
Which kind of atom is described above?
Parent/Radioactive Isotope
400
Dr. Randolph Wilson Bromery (1926 - 2013) was the first black geophysicist in the US Geological Survey. He was recognised for his work in magnetometry, which uses the Earth's magnetic field.
Which layer of the Earth is responsible for the magnetic field?
The Outer Core
400
Experiments can be complicated, but scientists are not perfect supercomputers. We want to simplify our work so it is easier to understand.
In an experiment, which variable should we keep as close to ONE as possible?
Independent Variable
500
Which layer consists of the crust and the upper part of the mantle?
Lithosphere
500
The layers of sedimentary rock above have experienced millions of years of change. What process could have caused all of layer T and most of layer S to disappear?
Erosion
500
Fill in the Blank: Radiometric dating is a very useful tool that can be used on practically any rock regardless of where it came from originally. The oldest rocks discovered on Earth came from meteorites and the Moon, and these rocks are evidence that the Earth is currently estimated to be about ______ years old!
4.6 billion
500
This deadly skin disease has been a major threat to people throughout history, and it is still largely unknown how it spreads to people. Thanks to the work of chemist Alice Augusta Ball (1892 - 1916), thousands of patients in Hawaii with this disease were able to receive the first effective treatment and return home.
Which disease did she create a treatment for?
Leprosy (Hansen's disease)
500
Most of science isn't based on experimentation, but is often based on paying attention to details, attempting to categorize different phenomenon, and analyze data with the intent of facilitating further investigations. These kinds of investigations are key to any and every topic in the sciences.
What kind of investigation is described above?
Observational Studies