Section 10-4Igneous rock features

Batholith

Batholith Large intrusive rock

body Hundreds kilometers

wide Magma cools

underground Old magma chamber

laccolith

Laccoliths are somewhat large intrusions that result in uplift and folding of the preexisting rocks above the intrusion.  They are also concordant types of intrusions.

Dike – Vertical intrusion that

cuts across rock layers

                                                                    

        Shiprock volcanic neck and dike, symbols of

New Mexico geology,west of Farmington, NM.

sill

Sill Horizontal intrusion of

magma between vertical layers or cracks

http://epod.usra.edu/archive/images/volcanic_sill_4.jpg

Volcanic neck

Volcanic neck – Hardened magma

inside of the vent Volcanic cone is

eroded away leaving the neck exposed

caldera

Top/crater of volcano collapses in on itself leaving a larger crater.

Caldera lake – Sometimes the crater

fills in with water creating a lake