Intrusive igneous rock

The powerpoint goes into detail about the different intrusive rock structures and includes an activity for the learners.

1. Intrusive igneous activity and landforms

2. Intrusion Is molten rock that forms slowly under Earths surface. Magma under the surface is pushed up slowly from deep in the Earth into any cracks or spaces. Sometimes pushes existing rocks out the way. Rock cools slowly into solid, different parts of magma crystalize into minerals.

3. Occur when magma fails to reach the surface. Magma moves from one part of crust to another. Features (On the next page) formed and were exposed after millions of years of erosion. Formed from volcanic activity. Intrusive igneous activity and associated features

4. 1) Batholith Huge dome shaped mass of igneous rock Largest intrusive rock. Can occupy an area as large as 100Km squared.

5. Laccolith Formed when magma intrudes into more or less horizontal sedimentary strata and strata is domed upwards in mushroom shape.

6. Lopoliths Magma intrudes sedimentary strata, underlying rock can’t support weight of newly formed landform. Floor subsides resulting in saucer like intrusive forms.

7. Monoliths Is a geological feature, such as mountain. Consist of single massive rock. Erosion exposes geological features and is made of hard and solid metamorphic or igneous rock.

8. Dyke Formed where magma forces way through rocks and solidifies to form vertical structure.

9. Sill Magma intrudes horizontally between rock layers.

10. What happens when magma reaches the earths surface?

11. Answer Lava explodes out of volcano, with solid particles and gas. 3 main types of materials ejected by volcanoes: 1) Gases Nitrogen, Co2, steam and sulfur oxide. 2) Fluid material Molten rock and water 3) Solid material Ash, pieces of rock and various lava forms

12. Please redraw and label and discuss the intrusive igneous rocks.