Over the last 24 hours, drilling has progressed slowly because of the unconsolidated nature of most of the rock we've been drilling through. This does not come as a complete surprise, since the PTA area of the saddle where the drill rig is located can be viewed as a basin that collects erosional products from Mauna Kea. In addition, the post-shield stage cones of this volcano (see below for an example) have erupted and deposited loose cinder that we have to drill through as well. The best drilling has been through solid lava rock, but so far we haven't encountered much of it.
Last night it was necessary to trip out and change the bit, because unconsolidated material eats away at drill bits much faster than hard rock does. As of about 3:00 pm today, we have progressed to 98 feet below the surface. The goal is to keep drilling slowly through this section until we encounter solid rock in which to set casing. At that point, we will attempt to widen the hole with a rotary bit and set casing on the solid rock formation at the bottom. The casing will extend to the surface and keep loose material from caving into the top of the hole as we continue to drill downward. Stay tuned for further updates on our attempts to stabilize the hole for better drilling penetration and recovery.
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