Formation of Rocks


Rocks are made from minerals. A rock can be generally defined as a group of minerals bound together in some way. The study of rocks is an important part of understanding Earth processes.

This lava is magma that poured onto Earth's surface during a volcanic eruption on the Big Island of Hawaii.

Homework:
Due Tuesday, 12-09-08

In textbook: read pages 104-107; do questions 1-5, on page 107.

Due Friday, 12-12-08

In textbook, read pages 118-126; do questions 1-2, 4-6

Comments

Post a Comment

Popular posts from this blog

Rock Cycle

Image
The rock cycle is a model of the natural changes that occur in rocks and rock materials on the earth. The diagram to the right distinguishes between those processes that take primarily at Earth's (external processes) and those that take place within the Earth (internal processes).  Internal processes, such as compression and heating require the conditions of extreme temperature and pressure that occur deep within the Earth. The rock cycle illustrates several important principals of geology. First, nearly all rocks are made from the remains of other rocks (coal and other organic sedimentary rocks are important exceptions).  Second, rocks are classified on the basis of their origin.  Finally, there are a variety of ways that rocks can change in response to changing conditions at the surface or within Earth. Homework  due Wednesday, April 6, 2011 Review Book:  read pages 55-56; do questions 54-60 on pages 56-57, and questions 1-10 on pages 59-60.
Read more

Phases of the Moon

Image
As moon orbits Earth, the Sun always illuminates one-half of the moon surface.  Viewed from Earth, the moon's phases are seen as different portions of the illuminated sphere. No other object in the night sky is as spectacular as Earth's moon.  For almost all of recorded human history, the moon has inspired myths, songs, poems, and superstitions. Phases of the Moon The moon completes one revolution around the Earth in 27.3 days. During this orbit, the illuminated area of the moon increases and then decreases. This effect makes the moon appear to change shape. These phases (apparent changes in shape) of the moon are caused by the constant changes in relative positions of Earth, the Sun, and the moon.  When the moon and the Sun are on the same side as the Earth, the moon's dark side faces Earth. At this time, the moon's illuminated side is not visible from Earth.  This is the new moon phase.  The above figure illustrates the way light and shadow on the orb...
Read more

Igneous Rock Classification

Image
The most common igneous rocks are classified using just two characteristics: Crystal size and color. For example, basalt is relatively dark in color (gray to black) and usually contains crystals to small to see without the aid of an optical lens.  On the other hand, granites are lighter in color (pink to gray) and have crystals that can be seen by the naked eye.  Igneous rocks are the only kind of rock that forms from hot magma, and all rock that crystallize from melted rock are igneous.  
Read more