Download presentation
Presentation is loading. Please wait.
Published byClemence Marsh Modified over 5 years ago
1
Bellringer Complete #5 on page 70 in your book. You do not have to write the question.
2
Sedimentary Rocks Science 7 Study Pack #4
3
Today’s Goals… I can explain how sedimentary rocks form from sediments
I can classify sedimentary rocks as detrital, chemical, or organic in origin.
4
Sedimentary Rocks 75% of rocks exposed at the surface of the earth are sedimentary Sediments are loose materials such as: rock fragments mineral grains remains of organisms bits of shell Carried to new locations by wind, water, ice, or gravity
5
Sedimentary Rocks Sediments come from already existing rocks that are weathered and eroded Rock forms when sediments are pressed and cemented together
6
Sedimentary Rocks Form as layers Older layers at the bottom
They were deposited first
7
Sedimentary Rocks Classified by their composition and how they form
Detrital Chemical Organic
8
Detrital Sedimentary Rocks
Made from pieces of other rocks Rock is first weathered (broken up) and then eroded (carried away) Sediments are then deposited (laid down) Pressure from layers of rock cause the pieces to become stuck together or compacted
9
Detrital Sedimentary Rock
Sometimes water and minerals flow between sediments and act as a natural cement to hold the sediments together Examples: Conglomerate: rounded sediments Breccia: sharp edged sediments
10
Conglomerate and Breccia
Animation
11
Chemical Sedimentary Rocks
Form when dissolved minerals come out of a solution Imagine a glass of salt water Examples: Limestone, rock salt (Halite) Many uses – page 75
12
Organic Sedimentary Rocks
Made up of the remains of once living things May contain fossils Examples: chalk, coal, some limestone
13
Coal Forms when pieces of dead plants are buried under sediments in swamps Compacted for millions of years Most coal formed during the Carboniferous period
Similar presentations
© 2024 SlidePlayer.com. Inc.
All rights reserved.