what is volcanic glass occurring in different colors but often black it forms from lava that cools so quickly that crystals have no time to form.
obsidian
100
What is today on the time line
0.0
100
to discover the creature or plant it came form
why are fossils important to geology
100
limestone What is at the bottom of the grand canyon
limestones
100
What is inner core is solid 4700'c to 4800'c 3 to 4 millions .at the center of the earth solid iron and nickel
inner core
200
What is dark -colored, coarse grained crystalline contains little if any quartz mostly composed of feldspar , olivine and pyroxene minerals.
What is gabbro
200
2 million years ago ice age was ruled by mammals like mammoths, saber tooth tigers and others
What is ice age
300
composed of volcanic ash and glass particles could be considered a sedimentary often light color and not very dense
What is tuff
300
66 million years ago meteor destroy the plants and water so the herbivore dinosaur's die and carnivores have no food
What was dinosaur's extinction
400
composed of large rounded pieces of rocks the grains are larger the those that makes up sandstone.
What is conglomerate
500
may be composed of the remains of sea creatures or form minerals precipitated from water calcium carbonate is the main ingredient fizzes when acid dropped on it