edHelper.com
Earth Science
When the Earth Hiccups



When the Earth Hiccups
Reading Level
     edHelper's suggested reading level:   grades 8 to 9
     Flesch-Kincaid grade level:   8.19

Vocabulary
     challenging words:    hiccupping, rayleigh, slippage, undeformed, determined, subducting, subducts, epicenter, mesosphere, seismologists, seismic, better, intermediate, divergent, mid-ocean, subduction
     content words:    Andrija Mohorovicic, New Madrid, South Carolina, Mississippi River, North America


Print When the Earth Hiccups
     Print When the Earth Hiccups  (font options, pick words for additional puzzles, and more)


Quickly Print
     Quickly print reading comprehension


Proofreading Activity
     Print a proofreading activity


Feedback on When the Earth Hiccups
     Leave your feedback on When the Earth Hiccups  (use this link if you found an error in the story)



When the Earth Hiccups
By Trista L. Pollard
  

1     Occasionally the Earth moves right underneath our feet. In some areas of our world, it moves enough to cause major damage. In other areas, the Earth merely hiccups. Earthquakes, according to seismologists, are movements of the ground caused by bursts of released energy. This energy is released when rocks move along faults. It is when these rocks are under stress that they suddenly move. Remember, faults are breaks in the bodies of rocks. Within these faults, the rocks slide in relation to other rocks.
 
2     So why do we have earthquakes? As rocks are positioned along faults, they are pressed together very tightly. In this situation, the friction between the rocks keeps them from moving past each other. This occurs when there is a locked fault. The fault remains locked until the stress becomes too great and slippage occurs. The newly unlocked rocks move past each other suddenly. Earthquakes occur because the slippage causes trembling and vibrating.
 
3     When you think of rocks, the word "elastic" does not come to mind. However, elastic rebound may also be a reason for earthquakes. Elastic rebound occurs when elastically deformed rocks suddenly return to their undeformed shape. On each side of the fault, rocks move slowly, and once the fault becomes locked, the stress increases. Eventually the stress reaches a point where the rocks cannot remain locked. At the point of stress, the rocks fracture; at their weakest points the rocks separate and rebound to their undeformed shapes.
 
4     Scientists have defined different parts of an earthquake. The focus of an earthquake is the point located below the Earth's surface along a fault. This is the point where an earthquake's first motion occurs. An epicenter is the point on the surface that is directly above the focus. As you can imagine, the depth of an earthquake's focus can vary. However, scientists have found that about 90% of continental earthquakes contain foci that are shallow. A shallow focus occurs within 70 kilometers of the surface. Intermediate foci earthquakes occur from 70 kilometers to 300 kilometers below the surface. Shallow and intermediate foci earthquakes usually occur away from subduction zones and closer to plate boundaries. Unlike earthquakes with shallow foci, intermediate and deep earthquakes tend to cause less damage once the energy reaches the surface. This is due to the greater distance the energy travels before reaching the surface. As it travels, it radiates outward and dissipates.

Paragraphs 5 to 13:
For the complete story with questions: click here for printable



Weekly Reading Books

          Create Weekly Reading Books

Prepare for an entire week at once!


Earth Science
             Earth Science


More Lessons
             High School Reading Comprehensions and High School Reading Lessons


More Activities, Lesson Plans, and Worksheets


Back to School
Graphic Organizers
Alphabet Worksheets
Sight Words
Math Worksheets
Mazes
50 States

Monthly Themes
January
February
March
April
May
June
July
August
September
October
November
December

Fractions
Place Value
Time and Calendar
Money
Earth Day
Solar System
Analogies
Nouns
Following Directions
Listening
Capitalization
Cursive Writing
Patterns and Sequencing
Dinosaurs
All About Me

Kindergarten
First Grade
Second Grade
Third Grade
Fourth Grade
Fifth Grade
Sixth Grade

Multiplication
Division
Main Idea
Cause and Effect
Measurement
Decimals
Rounding
Order of Operations
Verbs
Community Helpers
Adjectives
Plants
Grammar
Addition and Subtraction
Contractions
Bulletin Board Ideas
Word Searches
Crossword Puzzles
Printable Puzzles

Reading Comprehension
Reading Skills
English Language Arts





Copyright © 2011 edHelper