Texas, Our Texas Station Lab
Station 1
What changes did you observe in the limestone rock after adding acid drops?
Bubbling and rock dissolving
If limestone pieces represent rocks in nature, what do the acid drops represent?
Acid rain
What kind of weathering does this resemble?
Chemical
In nature, where would the acid come from?
Pollution
How is the action of chemicals like the action of wind and water?
Breaks the rock apart
What human activities may cause chemical weathering?
Too much pollution can be caused by factories, cars, etc.
Define Karst topography and tell which ecoregion(s) of Texas have this kind of landform. (Answer: Caves, caverns, and sinkholes)(Breaking down of bedrock such as limestone).
Answer: Karst topographyis a landscape shaped by the dissolution of a layer or layers of soluble bedrock, usually carbonate rock such as limestone. Mostly the EdwardsPlateau, Llano Uplift and part of the Trans Pecos region.
Extra information (Just to read): Karst landforms are generally the result of mildly acidic water acting on weakly soluble bedrock such as limestone. The mildly acidic water begins to dissolve the surface along fractures or bedding planes in the limestone bedrock. Over time, these fractures enlarge as the bedrock continues to dissolve. Openings in the rock increase in size, and an underground drainage system begins to develop, allowing more water to pass through the area, and accelerating the formation of underground Karst features.
Station 2
What was the effect of the waves on the sand?
The sand eroded (moved) to the other side of the pan.
Define weathering.
The breaking down of rock
Define erosion.
The moving of that sediment
Define deposition.
When the sediment settles somewhere
How does this activity relate to weathering, erosion and deposition?
Waves weather the rocks or shells over time into smaller pebbles and sand. The sand from the beach is eroded from one shoreline and deposited somewhere else.
How do weathering, erosion, and deposition by waves affect Texas? Which ecoregion(s)?
Texas has a large coastal area where there is a lot of erosion. There are sections of the coastline that are receding due to erosion while there are other sections of the coastline that are extending due to deposition. Homes and businesses are affected due to these changes.
How do hurricanes affect weathering, erosion, and deposition in Texas?
Hurricanes increase the speed with which rocks and other earth materials weather, erode and deposit.
Station 3
Which rocks/sediment are you able to move by blowing through the straw?
The smaller rocks or pebbles and the sand.
Which rocks/sediments represent weathered rocks? Why?
The sand and smaller rocks because they are broken down into smaller pieces.
Where are the rocks/sediments deposited when you stop blowing?
The rocks are deposited at the other end of the tray.
How does this activity model weathering, erosion, and deposition?
The wind weathers rock by constantly pounding on its surface. The weathered rock is carried (eroded), then put down (deposited) at another location.
How do tornadoes affect weathering, erosion, and deposition due to wind in Texas?
Tornadoes create high-speed winds that can weather, erode, and deposit rocks very quickly.
Station 4
In your model, what did pouring water through the funnel represent?
Flowing water from the source of the river
What are some limitations of this model?
This is on a much smaller scale, the pan needs to be tilted just right, you have to make sure to pour the water evenly, not too fast, etc.
When water was added, what happened?
Flooding and eroded the sides of the river.
How does the river act as an erosion agent?
The river carries and moves rocks and sediment.
How do rivers and streams affect weathering, erosion, and deposition due to water in Texas?
Rivers carry rocks downstream and weather them, then they are deposited at a different location in the river.
Why does Galveston have such brown water when other parts of the Gulf of Mexico have clear, blue waters?
The wave action churns up more sand and sediment than on other beaches. Also, it has runoff coming from other rivers, such as the Trinity River.
Station 5
What was the appearance of the marbles prior to being heated and dropped into ice water?
The marble was whole and smooth.
What was the appearance of the marbles after being heated and dropped into the water?
The marble cracked and broke apart.
What caused the change in the marbles?
Extreme temperature changes from hot to cold.
What might happen to the cracked marble?
More pieces of the marble may break off since it has fractures running through it.
How does the cracking of marble relate to the weathering of rocks?
Rocks will also crack and break down over time due to hot to cold changes.
Is weathering of rocks due to temperature changes, physical weathering, or chemical weathering? How do you know?
Cracking of rock due to temperature changes is physical weathering because there is no chemical change. It is only a sudden contraction or expansion of rock due to temperature changes.
Complete the graphic organizer below using words from this lab.
Texas is divided into ecoregions that include
Which show the natural effects of
Most likely caused by
and