Monitoring the Rift: Sundered Chasm

Objectives
Garren at Amber Ledge wants you to use the Arcanometer at the Sundered Chasm anomaly and return to him with the readings.
 * Sundered Chasm Reading Taken

Description
Did you feel that?! That was just an aftershock... you should've been here a few minutes ago!

I'm afraid I must call upon your services again. My instruments indicate that there is an immense disruption just west of here, far beneath the water's surface.

Just as before, I need you to take the arcanometer and capture the anomaly's data.

I'll cast a spell that will enable you to breathe underwater. If it wears off before you find it, come let me know and I'll renew its effects.

Rewards
You will receive:

Progress
Well, ?

Were you able to locate the anomaly?

Completion
It was how big?

That's impossible! I need to report to Dalaran at once!