The Brothers
The hills that make up The Brothers are among the Monaro’s most significant landmarks. The Brothers are significant from a number of standpoints. They are three ancient volcanoes and responsible for much of the geography of the Monaro we now see.
What makes the brothers?
The Brother peaks are volcanic plugs, that is, they are the remains of the internal cores of the volcanoes that have since weathered/ eroded over time. The highest peak of the brothers is South Brother at 1120m.
Approximately 65 eruptive volcanic sites have been mapped in the Monaro region ranging in age from 54 to 34 million years old. The lava that flowed from around 35 eruptive events filled the surrounding valleys. The basalt plains visible today are the remains of the valley floor lavas as the slopes and peaks of the original volcanoes have been largely eroded.
The Monaro basalts are Paleogene volcanic basalts formed between 23 and 56 million years ago.
Mt Mary - A new little brother?
Recent Urban Development on the Monaro has see the installation of a new baby brother. Read more here...
Sources:
https://www.elevatedsurveys.com.au/client_gallery/mountmary/