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If you want to find out more specific information about the Ocean Drilling Program (ODP) or the JOIDES Resolution go to: |
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1. In the journal entries it said that you sometimes worked 17-20 hours a day. I was just wondering how you stayed awake that long and stayed focused on your job and your goals that you had to accomplish? Hayes, A 17-hour day means that I get to sleep approximately 7 hours a day, which it is not too bad when you consider that you are on a ship and there are not too many distractions there. After a while, your body gets used to staying up and working more. Also, it helps when you have deadlines or some difficulties because the adrenaline is pumping and you do not feel as tired. Days when I worked 20 or more hours were not the norm so it means that I would work for a long time (up to 30 hours) and then get to rest for a while until I got back to a more normal shift. To answer your second question, this was my 7th cruise on the JOIDES Resolution and my 11th cruise overall on an oceanographic vessel. |
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1. What kind of rocks did you find and how were they made? Leo, Most of the rocks that we found were altered igneous rocks of continental origin. These are also called felsic volcanic sequences and their associated intrusive rocks. They are presumed to have erupted in a convergent margin (collision of two tectonic plates) or what is more commonly called an island arc setting. In this type of setting you are likely to find a variety of valuable hydrothermal ore deposits. These deposits range usually consist of massive sulfide deposits rich in both base and precious metals such as copper, silver, and gold. Understanding how such ore bodies were created in the past was one of the main scientific objectives of Leg 193. The deepest hole that we drilled was 387 meters below seafloor. The core recovery throughout most of the holes we drilled was low, but the all recovered rocks are important if you want to understand the geologic history of the area and determine what is currently going on in this active hydrothermal system. The high temperatures that we encountered were expected but the rate at which these temperatures rebounded from the point when we stopped drilling (and circulating cold water) to a week later was very interesting. Also, we encountered a lot of a sulfate mineral call anhydrite (CaSO4). This is not the first time that this type of mineral has been found in these environments. However, we thought that we were going to encounter more barite (BaSO4) than anhydrite because in this area. There is an abundance of barite on the seafloor and not much evidence for the presence of anhydrite was encountered in any of the previous studies that were made in the Manus basin. Anhydrite also contributed to some of the challenges that we encountered while drilling the holes because anhydrite tends to dissolve in fresh water. Since we use circulate fresh water to flush out the drill cuttings, the borehole walls became unstable when the anhydrite dissolved. The end result was that many of the borehole walls collapsed and these conditions made the situation extremely difficult for making deep holes without using some type of casing. If you want to know more details about the geology of the area or some of the preliminary results of the leg go to: http://www-odp.tamu.edu/publications/prelim/193_prel/193toc.html |
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1. What effect did the earthquake have on your drilling project? Jessica, The earthquake did not have any effect on our drilling efforts or at least none that we are aware of. Increased seismic activity could have caused increase fluid discharge on the vents, movement along local faults, or even a tsunami that may had affected our operations, but we did not observe any of these. As for the equator crossing, there were no apparent changes except that the pollywogs (people that had never crossed the equator on a ship) became shellbacks (veteran equator crossing people). The cores that we brought back are helping us to reconstruct the geologic history of the area and learn how these systems form and evolve through time. They are also allowing us to investigate how newly discovered life forms thrive in these hostile conditions. |
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1. Do the cores have to be stored in large refrigerators? If so why, and what would happen if they weren't? Michelle, The cores are kept refrigerated to keep them at temperature conditions that are close to their original temperatures and to prevent them from drying out. This is done to try to preserve the cores as best as possible for future studies. In most drilling legs, the scientists and crew stay onboard approximately 56 days. The drilling operations on each hole depend on the rate of penetration (how quickly you can drill through those particular rocks) which is highly dependent on the type of rock that we are trying to drill. For the most part, sediments tend to be softer than igneous rocks therefore the softer the rock the faster the penetration rate is going to be. The amount of time between drilling legs is highly dependent on the person and their association with the drilling program. For example, the crew sails 2 months on and two months off, meaning that they spend about 6 months a year at sea. The scientists sail once in a while depending on whether they apply to a specific leg and if they get invited. Some of the people in my group sail about once a year or once every two years. |
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1. How long were you away from home? Dave, I left New York on November 7th, 2000 and I returned on January 10th, 2001. That was a total of 64 days away from home. Out of that total, I spent approximately 54 days at sea. Estimating the time that I spent working is a little bit harder but taking into consideration that the last 10 days at sea were very hectic, I would say that I spent about 18 hours a day working on my duties as a Logging Staff Scientist. |
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1. What do you do if a storm hits you while drilling the hole? Jose, If the weather gets bad, we generally cease drilling operations until conditions get better. It can be dangerous to continue drilling in bad weather. This is especially true when drilling in shallow water because the ship’s response time to the heave (the up and down motion due to the waves) is much shorter. Drilling takes place on the rig floor, which is a platform about four feet above the bridge deck in the center of the ship. If we need to change a bit or the drill string fails, we do what is commonly called "pipe tripping". This is done in the following way:
Finally, regarding your questions about tsunamis, they are not necessarily bigger in the Pacific Ocean but they are most common there and this is why. Tsunamis are usually caused by a fault movement (a displacement in the Earth’s crust along a fracture) that creates a sudden change in water level at the ocean surface. Secondary events, such as underwater avalanches, produced by faulting may also produce a tsunami. The Pacific Ocean is the most common place for tsunamis because it surrounded by a series of trenches (long, narrow, and deep depressions on the ocean floor with relatively steep sides) that represent unstable margins between tectonic plates. The tsunamis are highly dependent on wavelength (the distance between wave crests), wave velocity (how fast is moving) and water depth. They typically move with velocities well in excess of 700 km/hr (435 mi/hr) and with wave heights of approximately 0.5 m (1.6 ft) in the open ocean so they are not easily observable until they reach the shore. Once the wave reaches the shore, the shape of the bottom slope slows them down, and the water begins to pile up to form crests that may exceed 30 m (close to 100 ft). Again, the big factors here are the wave velocity, the shape of the slope (how steep or shallow), and the water depth. |
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Gerry - When the volcanoes were erupting did the vents show any rise in discharge of the black cloud stuff, or were their any changes of the vents at all? Sam, This is an excellent question because this is something that many scientists have been trying to figure out for quite a while now. Unfortunately, at the time that the earthquakes occurred we were not monitoring the vent discharge. The only way to determine if there is an increase in fluid discharge during a seismic event is to monitor the vents at the same time that such an even occurs by having instruments at either the seafloor or in a borehole. During the last decade, ODP has invested considerable time and money installing long-term instruments in boreholes in order answer questions just like yours. Some of these instruments measure changes in temperature and pressure as a function of time so you can correlate the variations to significant seismic or tidal events. If you want to know more about these long-term instruments go to: |
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How much did the whole trip cost? Conor, The Ocean Drilling Program is a multi million-dollar program sponsored by approximately 22 different countries (http://www.oceandrilling.org/ODP/Members.html). The U.S.A. is the main contributor with a 2/3 partnership. Every year there are 6 different legs scheduled with different scientific objectives in different parts of the world. The program pays for complex operational (http://www.oceandrilling.org/ODP/ODPorg.html) and advisory structures (http://www.oceandrilling.org/ODP/SciAdv.html). Some of these costs include the lease of the ship, all drilling equipment, tools, personnel, salaries, food, and all the meetings and panel discussions that are necessary prior to a leg being scheduled or even departing from a foreign port. |
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1. What do the temperatures at the bottom of the holes indicate? Jessica, On the ship's surface the temperatures ranged from 60° F at night to low 90° F during the day. Sometimes the deck temperature was well above 100° F because of the heat reflection from the deck. In one of the boreholes we found that the temperatures rebounded from 60° C to slightly above 300° C, which is above 500° F. This rapid increase in borehole temperatures is telling us that there is hydrothermal fluid flow in borehole. This means that hot fluids are from the system are coming into the borehole through probably some fractures. |
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1. How do you get the ship to stay still when you're drilling in rough seas. Mike, The ship stays in position by using a dynamic positioning system, which is supported by 12 powerful thrusters. This system uses computers to maintain the ship over a specific target while drilling in water depths up to 8,200 meters, which is approximately 5 miles. In rough weather, the system usually works harder than when we have calm weather. If the weather gets to be too rough, we then pull out of the hole and terminate all drilling operations until the conditions improve. There are different criteria for terminating drilling operations due to rough weather conditions. These criteria are most critical in shallow water because the ship can be subjected to the greatest risk in shallow water. Some of the criteria used for stopping drilling operations in shallow water is the following: Drilling in 76 to 300 m water depth Coring operations will be terminated if:
Drilling in 301 to 650 m of water depth Same limitations as 76 to 300 m water depth, except:
In water depths greater than 650 m, the ship can withstand heave exceeding than 2 m but operations will be terminated if the conditions are expected to deteriorate. All the equipment onboard the ship is tied down to prevent things from rolling or injuring someone. Most tables also have edges that rise above the counter top to avoid this problem especially in the galley where you would not want you food to spill all over you or the person sitting next to you. When we loose either a drill bit or part of the drill string, we put together a new one by using a process called tripping pipe. This process means that we bring the entire drill string back onboard to replace the bit or the section of drill pipe that was lost. Each piece of pipe is threaded with a male and female end. That way they can screw into each other and make a long continuous string all the way to the seafloor and beyond. The process of changing bits usually takes several hours and it is dependent on how much drill string is in the water (water depth). |
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1. How can the drills lift fossils and rocks? Justin, Pieces of drill pipe are threaded together and lowered from the steel derrick through the moon pool (a seven-meter-wide hole in the bottom of the ship). As the pipe rotates, a heave compensator in the derrick acts as a giant shock absorber, so that the up and down movements of the ship are not transferred to the drill pipe. Then the cores can be cut and lifted smoothly. Techniques vary depending on what kinds of rocks are being drilled. For example, to drill through soft sediment or mud, a hydraulic piston corer is used. This mechanism uses seawater to drive a steel barrel through the sediment. To penetrate into harder sediment and rock, drill bits with cutting heads are used. As the hydraulic piston corer or drill bit cuts through layers of sediment and rock, cores are collected in tubes and brought up to the surface in segments as long as 9.5 meters (approximately 31 ft). The tubes are attached to a wire cable allowing the crew to pull the core up through the drill pipe. The amount and kind of drill bits that we have onboard the ship depend on the type of rocks that are expected to be drilled (sediments vs. igneous). However, there are usually more than 25 drill bits onboard. The ship has accommodations for approximately 115 persons with most of the accommodations being either two- or four-person rooms. |
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To ask a question, send it to iturrino@ldeo.columbia.edu |