Re: How does intrusive volcanism change the shape of the earth's crust?

The intrusive volcanism can change the shape of the earth's crust because 
it will bring a different mass into the affected region, and this mass is 
hotter than the previous existing rocks, causing dilatation and a thermal 
anomaly in the region, with uplift. 

There are many kinds of intrusive volcanism structures. One that is 
frequent is what we call sill, that has a tabular form, and can be 
observed in many regions. A great example of a sill can be found in the 
Roosevelt reservatory, Phoenix, Arizona, and another one that is classical 
is the Palisades, USA, 300 m thick.

Best regards

Eder C. Molina

eder@iag.usp.br
Dept. of Geophysics
IAG-USP
Brazil