41 Chapter 5: Time to Apply
Below are materials to support teaching and learning about scientific ocean drilling that connect to the content in this chapter. We also encourage you to explore the Resources for Educators page in this OER for links to additional exercises and assessments.
Time to Apply: Part A
Exercise 5.1
What is an Operations Superintendent?
View this video below about the roles and responsibilities of one the JOIDES Resolution’s operations superintendents, and respond to the questions.
(a) What were the unique challenges faced by the operations superintendent and crew during deep-sea drilling expeditions?
(b) How did these challenges vary depending on the location and type of material being drilled?
(c) How did working on the JOIDES Resolution foster cultural exchange and collaboration among an international team, and what could this teach us about global scientific endeavors?
Exercise 5.2
Based on what you learned about Coring in this chapter, there are differences in the drilling process when one is coring in soft, hard, and hardest formations. Look at the data table below, which was pulled from a Daily Operations Report sent out to expedition crew members and scientists during their time at sea, and answer the questions below.
Expedition 393 Core Data
| Site | Holes | Cored (m) | Recovered (m) | Recovery | Drilled (m) |
| U1559 | U1559 B | 12 | 49 | 26.2% | 0 |
| U1558 | U1558 E | 1 | 9.5 | 104.9% | 0 |
| U1558 F | 23 | 174.2 | 94.3% | 3 | |
| U1558 D | 38 | 220.2 | 45.8% | 0 | |
| U1583 | U1583 A | 1 | 9.1 | 100.4% | 0 |
| U1583 B | 1 | 9.4 | 99.8% | 0 | |
| U1583 C | 13 | 107.5 | 102.5% | 0 | |
| U1583 D | 1 | 9.5 | 105.7% | 0 | |
| U1583 E | 12 | 105.2 | 100.0% | 0 | |
| U1583 F | 28 | 138.5 | 33.1% | 101 | |
| U1560 | U1560 B | 32 | 153.4 | 39.7% | 0 |
| Expedition 393 Totals | 162 | 985.5 | 64.8% | 104 |
(a) What kind of formations do you interpret the expedition crew was drilling into at sites: U1559B, U1558D, and U1583C?
(b) For the boreholes where recovery was less than 100% (which means that there are parts of the core that are missing), what kind of information do you think is lost as the scientists try to understand the seafloor formation?
Exercises 5.3
150,000 Pounds of Stuck
In this chapter, you learned how the drilling substrate determines the type of corer used. Sometimes, certain sediment types, like soft-yet-sticky material, complicated the coring choice —just as IODP Expedition 392 experienced on the volcanic Agulhas Plateau.
Read the following excerpt from the JOIDES Resolution Onboard Outreach Officer about this situation, then answer the questions below.
Imagine shoving a straw through a peanut butter layer cake. When the substrate is sticky or hard, piston coring can become impossible. That’s when we resort to extended core barrel (XCB) rotary coring, which is not unlike corkscrewing into a fine cabernet—if you can envision the corkscrew with a hole in the middle, and the prize being not a sip of wine, but a long, lovely bit of cork. At any rate, I was watching while an enviously agile rig floor crew switched the system from piston coring to XCB rotary coring. Coming out of the drill string was a shiny stainless steel half-length advanced piston corer(HLAPC). Going into the hole, a black XCB rotary coring system.
Why make this switch, which eats up valuable hours of the 11 days we plan to be at this particular site? Not because of any trouble shooting the piston into the formation, but rather because of stickiness, according to Bill Rhinehart, who directs the drilling operation. The deeper we drilled, the more challenging it was to pull the core barrel back out. The marshmallowy substrate at shallower depths below the sea floor was now glue-like at 142 meters down.
We hadn’t yet hit rock, so we kept piston coring as long as possible, because the quality of core is so much better versus the more disturbed material recovered during rotary coring, Bill explained. It’s a delicate weighing of risks and benefits. The upside of piston coring is you get a relatively pristine sample. It has an orientation. Scientists can tell how it was situated in the ground, which is key for magnetic analyses, among other things.
“We may be stuck,” Bill remarked, not seeming alarmed. “It happens.” What happened next was unusual, however. And unfortunate.
When an assembly gets stuck, the rig floor crew tries to fish it out, essentially drilling over it to wiggle it free. If that fails, the only option is to pull. And then pull harder.
Most often, it pops free. But not always.
“We were 150,000 pounds of stuck,” Bill said, referring to having pulled to the tune of 68 tons—until something broke. The short, sad story is that the core and core barrel are still down in Hole U1579A, 76 meters below the sea floor. Since then, having moved just 20 meters to the north, with the JR’s dynamic positioning system holding us steady, we tripped all of the pipe back down to the seafloor to begin Hole U1579B—a 20-plus hour process. Not only expensive and labor intensive, it makes for bleak downtime when scientists are hungry for core.
But soon enough, the welcome words, “Core on deck!”
-Maryalice Yakutchik, Expedition 392, February 17, 2022
(a) Why do scientists prefer piston coring over rotary coring when possible, and what trade-offs must they consider when switching to XCB rotary coring?
(b) How does the changing consistency of the seafloor sediment impact the coring process, and what challenges does this pose for obtaining high-quality samples?
Time To Apply: Part B
The lessons posted on Educational Resources Using Ocean Coring Data are based on activities developed by educators and scientists who worked aboard JOIDES Resolution. These lessons have been revised by the Ameircan Geosciences Institute (AGI) to connect to NGSS and to include additional support for student learning. Here in Part B, we call attention to the high school-level materials that relate to the content of this chapter.
1. Certain properties of rocks and sediments are distinctive and can be used to help identify them. Some properties are also relatively easy to determine. Density is one such property. Students will measure and calculate the density of rock samples to compare the densities of oceanic and continental rocks, explore the relationship between density and depth in a given core and explain how density affects the movement of the mantle to predict interactions of tectonic plates at convergent boundaries.
2. After coring is complete at a site, the borehole itself becomes a laboratory. Instruments are sent down and data on the formation is collected continuous as the instruments are retrieved. Students will interpret data from this process, called downhole logging to explain why it is done and what it allows scientists to learn about the ocean floor.
The JOIDES Resolution website has an entire collection of Classroom Activities that include lesson plans, data exercises, digital interactives, posters, and career information. Here in Part B, we call attention to materials that relate to the content of this chapter.
3. Composition, structure, fracturing, and other factors may influence the length of time required for drilling through oceanic crust. Students will be able to calculate drilling rates over a three-day period during Expedition 309 by using the data provided.
4. Several sites on the Juan de Fuca Ridge axis and flanks have now been drilled and sealed by CORKS equipped with long-term pressure and other data collecting instruments. In September 2007, a party of about a dozen scientists, graduate students, and teachers from the United States and Canada traveled aboard RV Atlantis to the sites where they recovered long-term data, installed new equipment, and serviced CORK observatories. Students use CORK data to investigate the causes, effects, and relationships between fluid pressure measurements at the seafloor and the oceanic crust below.
