15SEDIMENTARY ROCKSSedimentary rocks are formed when bits of fragments of earth called sediments, are pressed together.
16SEDIMENTARY ROCKSSedimentary rocks form when bits or fragments of earth called sediments, are pressed or cemented together by earth’s processes. 75% of earth’s visual rocks are sedimentary rocks.
17LAYERS OF SEDIMENTARY ROCKS Sedimentary rocks are usually formed as layers. Layers are formed when trash is discomposed and when loses energy and deposits sand and other materials.
18HOW DIFFERENT LAYERS ARE FORMED Older layers of rocks are at the bottom from hundreds of thousands of years ago. Younger layers of rocks at the top are things that we deposit yesterday and today.
19CLASSICATION OF SEDIMENTARY ROCKS Sedimentary rocks are classified by their composition and by the manner in which they are formed. Sediments come from weathered and eroded igneous, metamorphic, and sedimentary rocks.
20EXAMPLES OF SEDIMENTARY ROCKS Sandstone SiltClay SandCoal GravelLimestone (chalk) Rock Salt
22They morph!! Metamorphic rocks are rocks that form from exiting rocks.
23THREE WAYS ROCKS MORPH!Rocks change when they are subjected to the intense heat associated with volcanoes or with bodies of magma.
24THREE WAYS ROCKS MORPH!Cont.Rocks morph when they are exposed to intense pressures from overlying rocks and sediments.
25THREE WAYS ROCKS MORPH!Cont.Rocks morph when hot, mineral- rich waters come into contact with rocks.
26FOLIATED METAMORPHIC ROCKS Foliated rocks form when mineral grains flatten and line up in parallel layers. Two examples are slate and gneiss.
27EXAMPLES OF METAMORPHIC ROCKS GneissMarbleSlateSchist
28NONFOLIATED METAMORPHIC ROCKS Layering does always occur in metamorphic rocks. The minerals grains grow and rearrange, however they do not form layers. The grains grow and interlockl like a jigsaw puzzle.