# Blog Posts Tagged "deep sea drilling"

## Intro to seafloor drilling

Topics:

Seafloor drilling is quite a technological feat, as I can now attest from first hand experience.  In today's blog, I will show you a bit of the technology employed to collect samples for the scientists on Leg 330.

## Retrieving the CORK

Hole 395A was first drilled in 1975, and on Friday, we successfully retrieved the CORK observatory that was installed in 1997 on ODP Leg 174B (14 years ago). Here’s a look at part of that process.

## Animals on the JR?

Who knew that there were so many animals onboard with us? Not real animals, of course, but machines and tools that help the drillers do their work. Lots of them have animals in their names…I guess drillers like animals. Listed below are just a few!

## What’s the story?

When we entered the Hole U1383B with the 14.75-inch bit, Charlie, the driller, found cement extending up from the casing shoe inside the 16-inch casing. This was a good sign that we likely had cement extending up on the outside of the casing as well. We need this to get a good seal for the experiment and to help support the entire seafloor structure.  We drilled through the cement, then lowered to the base of the 18.5-inch rat hole and started drilling. At that point, it was drilling slow and steady at ~2 m/hr. Our operations superintendent had about 32 hrs in the plan to drill ~69-194 mbsf—but this was calculated at 4 m/hr. We decided to drill a fair amount, but perhaps not that far. A lot would depend on penetration rate and hole conditions. Another issue was how long the bit will last. Bits typically last 40-60 rotating hours. However, in a hole like this, we will tend to not go too far past the lower limit—the last thing we want is to have a roller cone fall off!

## Imagining Deep-Sea Drilling

In this activity that combines math and art, students will learn about the process of deep-sea drilling by making their own reentry cone and simulating drilling activities. Students can color and construct their own reentry cone using the pattern provided, then use scale ratios to calculate drilling distances and measurements.

## Bit by Bit

RCB CORING, BIT #1: Although the penetration rates are relatively slow (with some faster intervals) and recovery is about what is expected, hole conditions appear to be reasonably good. The hole conditions are absolutely critical for us to be able to penetrate deeply, continue coring, and have a good hole for logging, packer tests, and CORKing. The next decision will be to determine when to stop coring with this Bit #1. A basic guideline based on a fair amount of experience (i.e., several decades of scientific ocean drilling) is that RCB bits typically last 40-60 rotating hours in hard rock. Although it’s always possible for a bit to last longer (or shorter!), the potential exists for it to have a cone fall off after too many hours—we all know too well what that does!

## JOIDES Resolution Playing Cards

They're here!  These JOIDES Resolution playing cards depict images from the JOIDES Resolution drill ship, and can be used in a variety of different ways. There are four groups of cards: People, Places, Drilling, and Recreation, and each group has eight pairs of images. In addition, there is one card without a match.