Meg Stewart: Aleutian Islands, Bald Eagles, Wildflowers, and Bunkers, July 8, 2019

Bunker Hill bald eagles

NOAA Teacher at Sea

Meg Stewart

Aboard NOAA Ship Fairweather

July 8 – 19, 2019

Mission: Cape Newenham Hydrographic Survey

Geographic Area of Cruise: Aleutian Islands, Bering Sea

Date: July 8, 2019

Weather Data from the Bridge
Latitude: 54° 59.104 N
Longitude: 166° 28.938 W
Wind: 21 knots SE
Barometer: 1006.6 mb
Visibility: 10 nautical miles
Temperature: 53° F or 11.5° C
Weather: Partly cloudy, no precipitation

Science and Technology Log

Today, we left the port at Dutch Harbor, Unalaska, Alaska and headed toward Cape Newenham. The mission for the Cape Newenham project is to gather detailed ocean depth data in order to knit together a comprehensive and highly detailed surface chart of the seafloor near Cape Newenham. I will talk about that process in my next post.

view of Dutch Harbor
A view of Dutch Harbor, Unalaska. The surrounding hills are volcanic, with just a thin layer of soil, and not a tree to be seen.

Dutch Harbor is a small town with a relatively deep port. The Ship Fairweather has a draft of 15.5 feet. “Draft” is the vertical length between the surface of the water and the bottom of the ship, which is called the hull. A ship’s draft determines the minimum depth of water a vessel can safely navigate and dock at a port. However, though the Fairweather has a 15.5 foot draft, the crew prefers a 20 foot depth of water at a port.

Map of Bering Sea
This overview map shows where Dutch Harbor is in relation to Alaska, the Pacific Ocean, the Aleutian Islands, the Aleutian Trench and Russia. The A-B line is shown for the cross sectional line in the next figure. Cape Newenham is out next destination.

Dutch Harbor is part of Unalaska Island, which is one of the string of Aleutian Islands. The Aleutian Islands are part of the notorious Ring of Fire that marks the edge of the Pacific tectonic plate. As the Pacific Plate moves and grinds past some plates (like along the North American Plate at the San Andreas Fault) or pulls away from other plates (like the Antarctic and Nazca plates, creating the East Pacific Ridge) or plunges beneath other plates (like the Philippine and Indian-Australian plates, where we get deep ocean depressions called the Mariana Trench and Tonga Trench, respectively), we see active volcanism (which is the “fire”) but also lots of earthquakes. The Aleutian Islands are volcanic in origin – the island chain is a volcanic arc – and are a result of oceanic crust of the Pacific Plate being subducted under the oceanic crust of the North American plate. The deep depression at this tectonic boundary – also called a subduction zone – is called the Aleutian Trench.

Aleutian Trench
Referring to the A-B line shown in the overview map above, this cross section shows the mechanics of the subduction zone at the Aleutian Trench at Unalaska Island.
Aleutian Trench tectonic map
This is a tectonic map of the Aleutian Trench area (the symbol shown as a dark black curved line indicates a subduction zone). The map shows the relative motion of the Pacific and North American plates. It is clipped from the New York State Earth Science Reference Table

Looking at a schematic drawing of the side-view, or cross section, of the Aleutian subduction zone, we can visualize what this looks like beneath the surface. The older and more dense oceanic crust of the Pacific Plate is plunging under the younger oceanic crust of the North American Plate – the more dense material sinks down or subducts – and the less dense material stays floating on top, and this process is all due to gravity. With time, as the oceanic material is drawn deeper into the subduction zone, it becomes hotter, starts to melt and then comes back up to the surface as volcanic material and a string of volcanoes forming parallel – and in this case, forming an arc – to the boundary between the Pacific Plate and the North American Plate.

Personal Log

Arriving at NOAA Ship Fairweather
Arriving at NOAA Ship Fairweather

I arrived at Dutch Harbor on July 6, after 14 hours and three legs of air travel. Fortunately, I made all my connections and my luggage arrived at the tiny Dutch Harbor airport. I was picked up by welcome smile for a nice person from the Ship Fairweather, got to the port and settled in to my stateroom. The “stateroom” is my sleeping quarters or room. I have it all to myself, it is very comfortable with a sink, a small bed, drawers and a closet to fit all my stuff, and there’s a TV that I haven’t yet figured out how to work.

My stateroom
My stateroom or sleeping quarters. Caution: panoramic photos make everything look larger than they really are.

Did You Know?

On my second day in Dutch Harbor, I went out with some new friends from the ship on a lovely hike on nearby Bunker Hill. I saw so many beautiful wildflowers along the trek and an enormous number of bald eagles. I had no idea that bald eagles would be so plentiful here, but they were everywhere. It was amazing! But the other interesting thing about this hike were the bunkers.  In June 1942, Dutch Harbor was bombed by the Japanese Navy (six months after Pearl Harbor) during World War II. At the time of the raid, Alaska was a U.S. territory, and following the bombing, the bunkers of the now-known-as Bunker Hill were built to help defend not only Alaska but the west coast of mainland U.S. And here I thought Dutch Harbor was only known for Deadliest Catch!

Quote of the Day

“Even if you never have the chance to see or touch the ocean, the ocean touches you with every breath you take, every drop of water you drink, every bite you consume. Everyone, everywhere is inextricably connected to and utterly dependent upon the existence of the sea.” Sylvia Earle

Meg Stewart: Getting Ready for an Adventure in Alaska

NOAA Teacher at Sea

Meg Stewart

Aboard NOAA Ship Fairweather

July 8 – 19, 2019

Mission: Cape Newenham Hydrographic Survey
Geographic Area of Cruise: Bering Sea, Alaska
Date: June 25, 2019


I am so excited about my upcoming experience as a NOAA Teacher at Sea. I will be on the NOAA Ship Fairweather from July 8 to 19 and will be participating on a hydrographic research cruise, one that is mapping the sea-floor in detail; more about that soon. We will embark from and return to Dutch Harbor, Alaska, which is part of the Aleutian Islands. If you are my current or former student, or you are a friend or colleague of mine, or you are an admirer of the Teacher at Sea program, I hope you will follow along on this ocean adventure as I post about my experiences while at sea.

Meg on catamaran
This is me on a catamaran off the coast of Barbados.

A little about me

I am originally from California. I went to the beach often to body surf and splash around, maybe sunbathe (I don’t do THAT anymore).   It was in California where I got interested in geology. I was pretty young when I experienced the 1971 San Fernando 6.5M earthquake and after that, earthquakes were a regular occurrence for me. When I moved to Hayward, California, in early 1989 to complete my bachelor’s degree in geology at California State University East Bay, I was living off-campus and had the “pleasure” of rocking and rolling through one of the longest earthquakes I every felt when the 6.9M Loma Prieta earthquake hit.  I moved on from there to the desert of Las Vegas, Nevada, to earn my Master’s in Structural Geology at the University of Nevada, Las Vegas. I didn’t feel any earthquakes in Nevada, but I did do my research on an active fault in southwestern Utah. I like to think of myself as a “boots-on-the-ground” kind of scientist-educator.

Meg teaching
Teaching graduate students about digital mapping.

My work and life experiences are such that for five years after grad school, I was a staff geologist at a large environmental consulting company. I loved that job and it took me all around the U.S.  One of the assignments I had was to manage a mapping project involving data from New York and New Jersey harbor area. From that experience I became interested in digital mapping (known as Geographic Information Systems or GIS) and switched careers. I went to work at a small liberal arts college as the GIS support person within the instructional technology group. In addition to helping teach professors and college students how to work with the GIS software, I helped teach about use of social media in teaching, use a mobile devices for data collection, integrating alternative assessments like using of audio and video, and I maintained two computer labs. While I was involved in those two different careers, I gained some adjunct teaching experiences at several different colleges and grad schools, teaching geology, environmental science and GIS.

Meg at University of the West Indies
At the University of the West Indies, Centre for Resource Management and Environmental Studies

Another professional experience that I’ve had that I am most proud of is I was a Fulbright Scholar in 2009-2010 to Barbados. My family and I lived in Barbados for a year while I was worked with the University of the West Indies, Centre for Resource Management and Environmental Studies (CERMES) I taught GIS to graduate students, I worked with some of the students on research projects, I traveled to Belize as a field assistant on a field studies trip with faculty members and CERMES students, and I had the privilege of working on a marine-based, community-driven mapping research project with a then PhD student (who has since earned her degree). My part of the project was to take the spatial data, organize it and create a user-friendly Google Earth KML file. She and I got to travel around St Vincent and the Grenadines and Grenada, teaching community members about the work, the available data, and how to access the Google Earth project file. 

New York state fossil
Behind the scenes at the American Museum of Natural History, checking out the official state fossil of New York, Eurypterus Remipes.

In 2015, I re-tooled yet again and was accepted into a challenging yet rewarding education program at the American Museum of Natural History in New York City. In 15 months, I learned how to teach with artifacts, took graduate courses in all manner or earth and space subjects, of course, had classes in pedagogical approaches, had two in-residence teaching experiences at area schools, all the while in the amazing AMNH, home of Night at the Museum. 

Meg and students at AMNH
These are two of my ninth graders checking out a piece of kimberlite with a diamond sticking out. We’re at AMNH in the Hall of Planet Earth.

Now as a public high school educator, teaching Earth Science to 9-12 graders in the Bronx, I have a strong foundation in the solid earth topics like plate tectonics, rocks and minerals, and geologic time. But Regents Earth Science class in New York also involves oceanography, meteorology, climate science and astronomy. 

Meg snorkeling
Yes, this is me, actually in the sea at Salt Whistle Bay, Mayreau Island in the Grenadines.

What compelled me to apply for the NOAA Teacher at Sea program is what motivates me throughout my other life decisions: I wanted to push against my boundaries and my limitations. I have always had a healthy respect for the sea, which was mixed in with a little fear. I saw the movie Jaws when I was young and impressionable, so I never really wanted to venture too far into the water beyond the waves. I didn’t even want to swim in lakes for fear of what might be traversing through the murky unknown. As I’ve aged, I’ve certainly grown less fearful of the water. I’ve traveled on sailboats and catamarans, I’ve snorkeled in the Caribbean, I’ve jumped into waters with nurse sharks and stingrays! But as a teacher who feels like she’s missing some key knowledge of her curriculum – oceanography – I want to challenge myself to learn-while-doing as I have the privilege of being selected to be a Teacher at Sea. I cannot wait!

Tom Savage: The Physical Geography of the Aleutian Islands, August 16, 2015

NOAA Teacher at Sea

Tom Savage

Aboard NOAA Ship Fairweather

August 6 – 23, 2018



Mission: Arctic Access Hydrographic Survey

Geographic Area of Cruise: Point Hope, northwest Alaska

Date: August 16, 2018

Weather Data from the Bridge

Latitude  68   38.8 N
Longitude – 166  23.8  W
Air temperature: 10 C
Dry bulb   10 C
Wet bulb  8.9 C
Visibility: 8 Nautical Miles   (8.8 miles)
Wind speed: 26 knots
Wind direction: east
Barometer: 1007  millibars
Cloud Height: 2 K feet
Waves: 6 feet

Sunrise: 6:33 am
Sunset: 11:51 pm

Physical Geography of Aleutian Islands

The Aleutian Islands are a product of a subduction zone between the North American and the Pacific Plate and known as the Aleutian Arc. Along this boundary, the Pacific Plate is being subducted underneath the North American Plate due to the difference in density.  As a result, the plate heats up, melts and forms volcanoes.  In this case the islands are classified as volcanic arcs.  As a result of this collision, along the boundary the Aleutian Trench was formed and the deepest section measures 25,663 ft!  For comparison purposes, the deepest point in the ocean is located in the Mariana’s Trench at 36,070 feet (6.8 miles)! Through the use of radioisotopic dating of basalt rocks throughout the Aleutians, geologists have concluded the formation of the island chain occurred 35 million years ago. (USGS). Today, there are 14 volcanic islands and an additional 55 smaller islands making up the island chain.

The Aleutian Islands – yellow line indicates subduction boundary (Courtesy of US Geologic Survey)

On the map above, the Aleutian Islands appear small. However, they extend an area of 6,821 sq mi and extend out to 1,200 miles!  In comparison, North Carolina from the westernmost point to the Outer Banks is 560 miles, half of the Aleutian Islands.  It takes roughly ten hours to drive from Murphy NC (western NC)  to the Outer Banks of North Carolina. Since this region of the North American plate and the Pacific Plate are both oceanic plates, Island Arcs are formed.  This is the same classification as the Bahamas, located southeast of Florida.

North American and Pacific Plates
Convergence of North American and Pacific Plates – Image courtesy of US Geologic Survey


Convergence of two Oceanic Plate – Image courtesy of US Geologic Survey

The image above depicts a cross section of the geological forces that shaped the Aleutian Islands.  As the two plates collide, the oceanic crust is subducted under the lithosphere further offshore thus generating the island arcs.  Unlike the west coasts of Washington, Oregon and California,  there is an oceanic/continental collision of plates resulting in the formation of volcanoes further on the continental crust, hundreds of miles inland.  Examples are Mount Rainier, Mount Hood, and Mount St. Helen’s which erupted in 1980.

Alpine Glaciers are prevalent throughout the mountainous region of Alaska. What about the Aleutians Islands? Today there are a few small alpine glaciers existing on Aleutian Islands. Alpine glacier on the Attu Island is one example, which is the western most island.


Personal Log 

One truth about being at sea is don’t trust the wall, floor or ceiling. Sometimes, the wall will become the floor or the ceiling will become the wall 🙂 Lately, the seas have become this ongoing amusement park ride.  Although the weather has been a bit rough, data collection continues with the ship.  The weather outside is more reflective of fall and winter back in North Carolina, though we have not seen any snow flakes.  After surfing the waves yesterday while collecting data, today the hydrographers are processing data collected over the past few days.

Yesterday was whale day!  Early afternoon, humpbacks were spotted from the port side of the ship (left side).   As the afternoon went on, humpbacks were spotted all around the Fairweather, at distances of 0.5 miles to 5 miles.  Humpbacks are considered the “Clowns of the Seas” according to many marine biologists.  Identifying whales can be tricky especially if they are distances greater than a few miles. Humpbacks are famous for breaching the water and putting on a show,  Yesterday we did not witness this behavior, however they were showing off their beautiful flukes.

Humpback whale fluke
Humpback whale fluke, photo courtesy of NOAA


Question of the Day:    Which whale species, when surfacing, generates a v shape blow?

Until next time, happy sailing!

Heather O’Connell: Misty Eyed for Misty Fjords, June 12, 2018


NOAA Teacher at Sea

Heather O’Connell

NOAA Ship Rainier

June 7 – 21, 2018

Mission: Hydrographic Survey

Geographic Area of Cruise: Seattle, Washington to Southeast, Alaska

Date: 6/12/18

Weather Data from the Bridge

Latitude and Longitude: 55°33.1’ N, 133 °16.1’ W
Sky Condition: Overcast
Visibility: 10+ nautical miles
Wind Speed: 23 knots
Sea Level Pressure: 1008 millibars
Sea Wave Height: 2 feet
Sea Water Temperature: 8.9°C
Air Temperature: Dry bulb: 12.8°C, Wet bulb: 9.6°C

Science and Technology Log

After discussing geology with resident expert Amanda Finn, I developed the following understanding of the geology of Alaska. Alaska accreted, or merged with the larger continent, from the Pacific Plate colliding with the North American plate. These shifting tectonic plates created catastrophic earthquakes and many of the rock formations that you see in Alaska today. The three thousand foot metamorphic rock mountains in Misty Fjords were most likely formed from these collisions. Initially, there were sedimentary rocks that were changed from heat and pressure into metamorphic rocks. Because the sedimentary rocks were altered, the original age of these rock structures cannot be determined.

While tectonic plates created the landmass, glaciers contributed to the structure of the mountains in Southeast Alaska, creating fjords. A fjord is a narrow inlet of the sea created by a glacial valley with steep cliffs. Seventeen thousand years ago, Misty Fjord was covered in ice. As the ice melted, long narrow inlets were created that filled with ocean water. Mineral springs and volcanic activity still exist around these areas where they are closer to fault lines. It was determined by NOAA scientists in 2013 that Misty Fjord has a sunken cinder cone volcano that must have formed after the glaciers created the fjords thirteen thousand years ago. As Amanda explains, “The disappearance of all the pressure from the overlying ice caused Earth’s crust to bounce back in the area, uplifting rock and carrying magma chambers closer to the surface, causing the volcano to form. This added traces of igneous rocks to the metamorphosed sedimentary rock in the form of quartz deposits. As more ice melted and the water level rose, the cinder cone was eventually submerged underwater.”



Alaska Geology

Connor, Cathy. Roadside Geology of Alaska.

Adjusting a Compass

I met a compass adjuster who was picked up in a launch from San Juan islands who learned his skill from an apprentice. He carried a wooden box with his equipment and seemed like he arrived from another time period. I was fortunate to witness this annual ritual that compares the direction of the ship according to the magnetic compass with true magnetic North in a process known as swinging the compass  A compass adjuster observes the difference between the ship’s compass and the four cardinal and four intercardinal directions to determine the difference. Since North and South were only one degree off, the magnets on the compass did not need to be adjusted. If there were a larger discrepancy between the two values, then magnets would be moved around until the directions came into alignment.

Captain Keith Sternberg swinging the compass from the flying bridge
Captain Keith Sternberg swinging the compass from the flying bridge

A compass functions based on the Earth’s inner molten iron core which generates a magnetic field around the Earth. The needle in a compass points towards the magnetic pole, which is not necessarily the same as the geographic pole. This difference between magnetic North and true North is known as magnetic variation. In addition to magnetic variation, each ship has a magnetic fingerprint that alters the magnetic compass slightly. If welding were done with metal, especially iron, this would change the magnetic signature of the ship. The combination of compass deviation and magnetic variation alters the true bearing of the ship and must be considered when viewing the bearing of the compass.

Since a magnetic compass differs from a true bearing, NOAA Ship Rainier has two gyrocompassses that are actually used for navigation. Each of these have a wheel spinning a gyroscope which is parallel to the Earth’s center of rotation, and do not rely on magnetism but depend on the Earth’s rotation and gravity. The spinning gyroscope, based on inertia, will always maintain its plane of rotation. Since these gyrocompasses are not altered by the magnetic signature of the ship and provide a true North reading, they are utilized in navigation. The NOAA Corps navigator plans the track lines of the course of the ship based on the true North reading of the gyroscope compass and is the bearing that is observed from the bridge of Rainier. The magnetic compass acts as a backup if the vessel were to lose power.

Gyrocompass on Rainier


Personal Log

As I was relaxing in the lounge about to watch Black Panther yesterday evening, a call came in requesting my presence on the Bridge. When I entered the fresh air, granite mountains with ridges full of melting snow waterfalls and a breathtaking view welcomed me. To say I was awe inspired would be an understatement. We were in Misty Fjords within the Tongass National Forest, part of the nation’s largest forest about 22 miles west of Ketchikan. Observing a sliver of this almost 17 million acre temperate rainforest with evergreen trees amongst misty clouds for a brief period of time includes a moment that I will treasure. I was happy to share this experience with other crew, survey technicians and NOAA Corps members who weren’t currently on shift. While appreciating  this beauty, I thought of a Japanese saying, “Iche-go Ich-e,” which means this moment only happens now. Observing the still glassy water reflecting the cloudy sky against green islands and three thousand foot mountains touched my soul. The enormity of the steep granite humbled me as I appreciated it in its untouched state. This pristine environment existed from a landscape formed ten thousand years ago by a massive glacier that created this geological phenomenon. Luckily, this Tongass National Forest was claimed to be a protected zone in 1978 by the president. I’m grateful for this natural beauty that invites a tranquil, peaceful feeling. When a blow spout of a whale appeared off the port side of the vessel, my elation couldn’t be contained and I was overwhelmed with gratitude.

Observing Misty Fjords in the Inner Passage
Misty Fjords in the Inner Passage


Did You Know?

Lookouts use a coordinate plane-like reference for directions. If you are standing at the center of the Bridge, similar to the origin of a coordinate plane, then the y-axis would be dead ahead. The x-axis, or 90 degrees to the right would be beam starboard, while to the left would be beam port. To the right forty five degrees would be broad off starboard, while to the left forty degrees would be broad port. If you count the three equidistant points leading up to forty five degrees on the right hand side of the ship, you would command one off, two off or three off starboard respectively.

Cindy Byers: Mud Volcanoes at Sea? May 6, 2018

NOAA Teacher at Sea

Cindy Byers

Aboard NOAA Ship Fairweather

April 29 – May 13, 2018


Mission: Southeast Alaska Hydrographic Survey

Geographic Area of Cruise: Southeast Alaska

Date: May 6, 2018

Weather from the Bridge

Latitude: 57 43.3 N
Longitude: 133 43.3
Sea Wave Height: 0
Wind Speed: 2 knots
Wind Direction: 202
Visibility: 8 Nautical Mines
Air Temperature: 14 C
Sky: High Cirrus Clouds   


Science and Technology Log

When I first learned that I would be on NOAA Ship Fairweather, one of the possible sites, I was told, was a survey including a mud volcano.  I did not know anything about mud volcanoes.  I knew about ice volcanoes on moons in our solar system,  but not about mud volcanoes. NOAA Ship Fairweather found evidence of the methane seeps coming from mud volcanoes, while surveying the Queen Charlotte fault last season.  A seep is where gases from below the surface comes out. The area surveyed the first week I was on the ship was just north of the seeps. I wanted to know more so I could share this information. Here is a little background.

Cindy Byers from the ship’s deck in Southeast, Alaska

In 2015 geologists found a 700 foot gas plume and a couple other active mud cones along the Queen Charlotte – Fairweather fault. Although this fault is not in a highly populated area, it is very active. In the area where the geologists were surveying, liquid natural gas plants and a busy port were close by.  They already knew of earthquakes along the fault and that an earthquake in the area today could cause a landslide and generate tsunamis on shore.  Older mapping done in the area showed past landslides. But the 2015 survey was looking for the “seeps.”

Scientists first noticed the methane plume coming from the area near the fault.  The seep was from an underwater mud volcano. A mud volcano does not have to be made of igneous rock like a traditional volcano.  It is formed from gases and mud creating a volcano shaped cone.

Geologists have questioned whether these mud volcanoes may provide a lubricant that could actually lessen the friction on the fault in the area. It would cause the tectonic plates of area to slowly creep along.

NOAA Ship Fairweather also found these seeps during a mapping of the ocean floor along the fault.  Below on the right are the plumes of gas rising from the sea floor. Look how high they are rising.  Also notice the fan shape on the right. That shows the width of the multibeam sonar at this depth. The colored area on the left are also from NOAA Ship Fairweather’s multibeam sonar with the blues being deeper areas of the seafloor and green to yellow to red getting more shallow.  The circled areas show where the seeps were found while the fault line was being mapped.

Soundings from the Multibeam Sonar over a mud volcano.


Datum from NOAA Ship Fairweather showing a seep.

Life under the sea?

At these seeps, geologists have also found animals that live off of the nutrients of chemosynthetic bacteria.  This is bacteria that, instead using the energy of the sun (photosynthesis,) to make energy, they use the materials that come from thermal vents in the ocean floor.

Mud vulcano
Mud Volcano Photo credit NOAA


What are other geologic wonders of the area?

First of all there are hot springs! I learned about these hot springs from several of the people on NOAA Ship Fairweather.  They report it to be a fun place to visit for a little well deserved time off. There are many hot springs in other areas of Southeast Alaska too.  It is a draw for tourists to the area. The hot springs are produced because water seeps down a crack in the Earth’s surface and gets heated, then the super-heated water rises to the surface.

The geology of rock types of the area are also a wonder.  It is actually quite complicated, the landscape and seafloor features have been influenced by glaciation, volcanism and plate tectonics, and these geologic influences are still present today. The surveying on NOAA Ship Fairweather is vital to the understanding of the geology that shaped the area.  The clues that are beneath the sea help geologist begin to understand southeast Alaska’s dynamic past, and help to predict the geologic future.


Personal Log

After one week on the ship I feel like I just might have to stay!  The surveying is really interesting and the views are amazing. When I first arrived I was confused by the passageways and ladder wells on the ship, but now it seems so easy!  

This is my room on NOAA Ship Fairweather

This is the” Mess” (where we eat.)

I have discovered a few of my favorite places!  I love my small room with its own port hole. I really enjoy all of the meals and having time to talk to everyone onboard.  People come from all over the US and do a variety of jobs on the ship.

Member of NOAA Corps marking our location on a chart.


Tomorrow I will have a chance to go off the ship on the small boats. That sounds like great fun!


small boat
These are the small boats used for mapping in places that the ship can not do safely.


Did you know?

We just got to a new area with glaciers.  The one we could photograph today is Sumdum Glacier.  It sounds like a really funny name. It is a Native American word meaning, the sound glaciers make when they are calving, which is what it is called when ice falls off of them.

Sumdum Glacier
Sumdum Glacier


View from the ship
This is the view from the place the ship is anchored

Some information from:

“Active Mud Volcano Field Discovered off Southeast Alaska.” Eos, 30 Nov. 2015,

Kelly Dilliard: Introduction, May 3, 2015

NOAA Teacher at Sea
Kelly Dilliard
(Almost) Onboard NOAA Ship Gordon Gunter

May 14 – June 5, 2015

Mission: Right Whale Survey
Geographical area of cruise: Northeast Atlantic Ocean
Date: May 3, 2015

Personal Log

Hello from South Dakota! My name is Kelly Dilliard and I am a college professor at Wayne State College (WSC) in Wayne, NE. Wayne State College is one of three schools with the Nebraska State College System and it is located in northeast Nebraska. I actually live in Vermillion, South Dakota, due north of Wayne and commute to school every day. My husband, Mark Sweeney, is an Earth Science Professor at the University of South Dakota in Vermillion. We are located about 45 minutes northwest from Sioux City, Iowa and about an hour south of South Falls, South Dakota.

Map of locations.
Map of eastern Nebraska and parts of Iowa and South Dakota showing locations of where I am coming from.

Photo of me at Malibu Beach.
Me at a cove beach near Malibu, California in July of 2014. Taking lots of photographs and videos to use in my teaching.

I teach all sorts of Earth Science courses at WSC including Introduction to Geology, Environmental Geology, Historical Geology, Rocks and Minerals, Oceanography, and Introduction to Meteorology. I try to create a hands-on experience for my students, but teaching in Nebraska has its drawbacks. We are far from some of the best geology sites and from the ocean, so instead of taking my students to the rocks or the ocean, I try to bring the rocks to my students in the form of specimens, photographs, and videos.  I believe that my students benefit from exposure to these samples and from the experiences that I bring into the classroom.  I hope this experience out at sea will help me bring more of the ocean to them.  As I teach mostly to future science teachers, I also hope this experience will open them up to taking similar opportunities to gain useful experiences to use in their own classroom.

Family at Black Canyon of the Gunnison.
My husband, Mark, myself, and our puggle, Penny Lane, at Black Canyon of the Gunnison National Park, Colorado, July of 2014.

As a youngster I had an interest in two sciences… geology and oceanography. I spent time in Hawaii when I was in fourth grade and fell in love with volcanoes and humpback whales. When it came to deciding on a major in college, I decided on geology and I have been actively engaged in researching and teaching about the Earth for the past 20 years. I am originally from eastern Pennsylvania, but through my graduate and professional career have lived in various states across the United States. I have three degrees in Geology, including a PhD from Washington State University.

Me and my brother in front of sign
My brother and I in April of 1986 standing by the map of the “Save the Whales” walk we took part in.

While I have an interest in oceanography and teach an oceanography class, I have never actually taken a formal oceanography course. I applied to the NOAA (National Oceanic and Atmospheric Administration) Teacher at Sea (TAS) program to gain some ocean research experience and to bring that experience back into my classroom. The Teacher at Sea program is celebrating it’s 25th Anniversary this year and is, as I am finding out, a wonderful program (link to TAS program)! I was selected to take part in a Right Whale Survey off the Northeast Coast on board the NOAA ship the Gordon Gunter (see the ship’s website for information and photographs). I never dreamed that I would also be getting exposed to a “what could have been” experience, that is, if I had decided to study oceanography and whales 20 years ago as an undergraduate.

So let me tell you a little about what I have learned so far about the North Atlantic Right Whale.  The North Atlantic Right Whale (Eubalaena glacialis) is an endangered species and is protected under both the U.S Endangered Species Act and the Marine Mammal Protection Act. Right whales were heavily targeted by whale hunters, being prized for their high blubber content, the fact that they float when killed, and their relative sluggishness. They were the “right” whale to hunt. Right whales are baleen whales like the humpback whale, but feed mainly by skimming through prey at or near the surface of the ocean. Right whales are recognized by their callosities, or rough skin (white in color due to whale lice!), on their heads. For more information on Right Whales check out the NOAA Fisheries article on them.

Right Whales
North Atlantic Right Whales. You can see their callosities. Photo credit: NOAA Fisheries

Next week I will be flying to Boston, Massachusetts and meeting up with the Gordon Gunter at the Woods Hole Oceanographic Institute. But before then, I have to finish off the semester, participate at the WSC graduation, put in my garden (hopefully), and pack for my trip. The next time you should hear from me, I should be aboard the Gordon Gunter.

Map of home and WHOI
Map indicating where I live/work and where I will be leaving from for the Right Whale Survey.

Jessie Soder: Geology on Georges, August 17, 2011

NOAA Teacher at Sea
Jessie Soder
Aboard NOAA Ship Delaware II
August 8 – 19, 2011 

Mission: Atlantic Surfclam and Ocean Quahog Survey
Geographical Area of Cruise:  Northern Atlantic
Date: Wednesday, August 17, 2011

Weather Data
Time: 12:00
Location:  41°19.095 N, 71°03.261
Air Temp:  22°C (°F)
Water Temp:  21°C (°F)
Wind Direction: South
Wind Speed: 7 knots
Sea Wave height:  0
Sea Swell:  0

Science and Technology Log

Gulf of Maine: Including Georges Bank

So far, we have spent this entire trip on Georges Bank.  This famous geographical location off the east coast of the United States is something that I had only heard about before this trip.  After several tows over the past week I have been able to see a variety of materials brought up from the ocean floor of Georges Bank.  I have seen loads of clams, empty shells, sand, mud and clay, and smooth polished rocks.  We have even pulled up a few boulders that must have weighed a couple of hundred pounds.  It was the smooth polished rocks that caught my attention. How would a rock from the bottom of the ocean become smooth and rounded?  It probably meant that Georges Bank must not have always been the bottom of the ocean.

During the Wisconsin Glaciation the ice reached its maximum around 18,000 years ago.  The Laurentide ice sheet paused in the area of Georges Bank and Cape Cod and left behind a recessional moraine that created these landforms.  This ice also had several meltwater streams flowing from it and these streams were responsible for the polishing the rocks and cutting some of the canyons found on the seafloor today.  The Northeast Channel off the northeast side of Georges Bank was the principle water gap for most of the meltwater.

Smooth Polished Rocks From the Ocean Floor

Georges Bank is a huge oval-shaped shoal bigger than Massachusetts that starts about 62 miles offshore.  It is part of the continental shelf and its shallowest areas are approximately 13 feet deep and its deepest areas 200 feet.  In fact, thousands of years ago Georges Bank used to be above water and an extension of Cape Cod.  About 14,000 years ago the sea rose enough to isolate this area and it was home to many prehistoric animals such as mastodons and giant sloths.  Today, traces of these animals are sometimes found in fishing nets!  These animals died out about 11,500 years ago when the sea level rose further and submerged the area.

Georges Bank is a very productive fishing area in the North Atlantic.  (The Grand Banks is more productive, but not as geographically accessible as Georges Banks.)  Why is Georges Bank a prime feeding and breeding area for cod, haddock, herring, flounder, lobsters, and clams?  It has to do with ocean currents.  Cold, nutrient rich water from the Labrador Current sweeps over the bank and mixes with warmer water from the Gulf Stream on the eastern edges of Georges Bank.  The mingling of these two currents, plus sunlight, creates an ideal environment for phytoplankton, which is food for the zooplankton.  In fact, the phytoplankton grow three times faster here than on any other continental shelf.  All of this plankton feeds the ecosystem of fish, birds, marine mammals, and shellfish that flourish on Georges Banks.

Personal Log

Yesterday we left Georges Bank for stations off the coast of Rhode Island.  After dark, I stepped out on the back deck and Jimmy pointed out the lights of Nantucket and Martha’s Vineyard.  We were in sight of land for the first time in a week.  It wasn’t long before people had their cell phones out and were making calls.

A few times during this trip I have thought about sailors in the past and how they would leave for months, and even years, at a time and not have contact with their families and loved ones until they returned.  I have had email contact this entire time, yet I am really excited to go home to see those that I miss.  I can hardly imagine what it would be like to be gone for a year with no contact at all.

Throughout this trip I have been getting to know others on this cruise.  I have learned that several of them have families and young children at home.  Many of them are at sea for many weeks, or months, a year.  After being on this cruise, I have gained a lot of respect for people who choose to work on the ocean for a living.  It takes a certain type of person who can work hard, maintain a positive attitude, and live away from their home and loved ones for extended periods of time.  It has been an honor to work with these people.

Christine Hedge, September 14, 2009

NOAA Teacher at Sea
Christine Hedge
Onboard USCGC Healy
August 7 – September 16, 2009 

Mission: U.S.-Canada 2009 Arctic Seafloor Continental Shelf Survey
Location: Chukchi Sea, north of the arctic circle
Date: September 14, 2009

Dr. Hall standing by the hovercraft before it is inflated
Dr. Hall standing by the hovercraft before it is inflated

Weather Data from the Bridge 
Latitude: 720 46’N
Longitude: 1580 24’W
Temperature: 350F

Science and Technology Log 

Doing science in the Arctic is challenging.  The weather is difficult, the ice is ever changing, and the expense of operating an icebreaker, aircraft, or helicopter is quite high.  So, how else can people get out onto the ice to study the ocean and the geology of the seafloor? One interesting project uses a hovercraft (think air hockey), which skims over the ice on a cushion of air. Using a hovercraft to study the most inaccessible places in the Arctic is not a new idea. But, Dr. John K. Hall, a member of our science party has taken this idea and run with it.   John has a long history of polar exploration under his belt. Including 13.5 months floating around the Arctic on a 90 square kilometer, 60-meter thick ice sheet known as Fletcher’s Ice Island (T-3) during the 1960’s. His latest project has been to purchase and equip a hovercraft to go where icebreakers cannot (areas of VERY thick ice).

Norwegian students parked on the ice doing research. The white tent protects the scientists while they collect data through a drill hole in the ice.
Norwegian students parked on the ice doing research. The white tent protects the scientists while they collect data through a drill hole in the ice.

The hovercraft was completed in 2007.  She is called the R/H Sabvabaa, which is the Inupiaq word for “flows swiftly over it.”  This hovercraft was designed specifically for doing science in Arctic conditions. It is equipped with all the comforts of home and all the latest technology.  From this research platform scientists have access to echosounding and seismic equipment to study the sea floor.  They can also park the Sabvabaa easily on a floe, get out on the ice to drill, photograph, and collect samples from under the ice.  This small 40-foot vessel (it fits in a semi-truck container) has great potential as a way for scientists to collect data in heavy ice conditions.  For more information about the Sabvabaa check out this website.

Classroom on the Ice 

Could you imagine being one of the first people to ride the hovercraft over the pack ice?  Since 2008, 16 lucky Norwegian high-school students have had that honor.  A competition was held as part of the Norwegian International Polar Year (IPY) program.  This competition set out to find Norwegian students ages 14-18 who are interested in careers in polar geophysics. A pair of students and a pair of researchers worked from the Sabavaa for one-week intervals. During their time on the Sabvabaa, the winning students participated in geophysical, geological, and oceanographic studies on drifting ice. They also had 4 encounters with polar bears!  What a great opportunity for these students. If you are interested in the student blogs from these trips (which are written in Norwegian) do a Google search for Sabavaa and have Google translate them.

FOR MY STUDENTS: Remember, not all scientists work in labs wearing white lab coats!  Many researchers lead exciting and adventurous lives. 

Paul Henkart teaching Nikki Kuenzel and Christina Lacerda.
Paul Henkart teaching Nikki Kuenzel and Christina Lacerda.

Personal Log 

As an educator, one of the best parts of this expedition has been to watch the mentoring that goes on. The scientists and professors in the science party have decades of research experience to share. It is not unusual to find one of these veteran Arctic explorers sharing their expertise with graduate students from the University of New Hampshire. Not only do these “mentor scientists” have great technical expertise. They are also really good at explaining complex ideas in a very simple way.   This has been wonderful for me since my background is in biology – so geophysics has been a challenge. The graduate students on board are not only learning science from the masters – they are hearing great adventure stories about past polar adventures before we had helpful technologies such as GPS and multibeam echosounders. Everyone on the Healy is in “learning mode”.  The Coast Guard crew, teachers at sea, scientists, and students are constantly asking questions and sharing expertise.

Christine Hedge, September 9-11, 2009

NOAA Teacher at Sea
Christine Hedge
Onboard USCGC Healy
August 7 – September 16, 2009 

Mission: U.S.-Canada 2009 Arctic Seafloor Continental Shelf Survey
Location: Chukchi Sea, north of the arctic circle
Date: September 9-11, 2009

From Latitude: 790 6’N/ Longitude: 1550 47’W
To Latitude: 780 3’N/ Longitude: 1590 41’W

Alex Andronikov labels and bags rock samples for further study.
Alex Andronikov labels and bags rock samples for further study.

Science and Technology Log 

Exploring the Unknown 
Geologically speaking, parts of the Arctic Ocean are some of the least explored areas on earth because they are often covered with thick ice. Geologists know there is an ultra-slow spreading center (where seafloor pulls apart) called the Gakkel Ridge.  They know where major features such as abyssal plains, plateaus, and ridges are, but the story of how this area formed is still the subject of much discussion. Where exactly are the plate boundaries in the Arctic?  Which direction are they moving?  Which forces formed the Arctic Basin?  These are great questions that geologists continue to investigate. In 7th grade we study plate tectonics.  Our textbooks contain maps showing where the plates are pulling apart (divergent boundaries), pushing together (convergent boundaries), and sliding past one another (transform boundaries). I had never noticed before this trip that clear plate boundaries are not shown under the Arctic Ocean.

FOR MY STUDENTS: There are some great animations showing plate movements at this site.

Looking Back in Time with Rock Samples 

Kelley Brumley and Alex Andronikov are geologists on board the Healy. They have been analyzing the data collected by the echosounding instruments to better understand the forces at work here. But what they have really been looking forward to is seeing what type of rock the seamounts, ridges, and plateaus below the Arctic Ocean are made of, and how these features were created.

Our first 2 dredge sites brought up muddy sediment and lots of:

  • Ice rafted debris: These are rocks that are frozen into ice that breaks from shore and carried out to sea. They can come from glaciers, or river deltas or any shoreline.  Some show glacial striations (scratches left behind by glaciers).
  • Coated sediments: These are crumbly, compressed mounds of sediment coated with a dark precipitate.

Dredge #2 was a muddy affair.  Using the hose, I helped separate the sediment from the rocks.  That’s me in the turquoise gloves!
Dredge #2 was a muddy affair. Using the hose, I helped separate the sediment from the rocks. That’s me in the turquoise gloves!

The next 3 dredges broke off rock samples from the steep slopes over which they were dragged. This was what the geologists were hoping for – samples of bedrock.  The rock samples that were dredged up show us that the geological history of the region is very complex.  Analyzing the chemistry and mineral composition of these rocks will help to answer some of the questions Kelley, Alex, and other Arctic geologists have about this part of the Arctic Ocean.  The rocks are cleaned, carefully labeled, and shipped to Stanford University, the University of Michigan, and the USGS (United States Geological Survey) for further study. Who knows, maybe the rocks that were collected today will help to clarify models for the geologic history of this part of the Arctic Ocean.

Personal Log 

On September 11, I was able to call my students in Indiana. Jon Pazol, (ARMADA teacher at sea) has an Iridium satellite phone that he graciously allowed me to borrow.  How fun to stand on the helicopter pad of the Healy and field questions from Carmel, Indiana.

Rock samples from a successful dredge operation
Rock samples from a successful dredge operation

Dredges sometimes bring up more than rocks and sediment. This arthropod came up with one of the dredge samples.
Dredges sometimes bring up more than rocks and sediment. This arthropod came up with one of the dredge samples.

Calling my students.  You can see in the background that there is much more ice than a few days ago.
Calling my students. You can see in the background that there is much more ice than a few days ago.

Christine Hedge, September 5, 2009

NOAA Teacher at Sea
Christine Hedge
Onboard USCGC Healy
August 7 – September 16, 2009 

Mission: U.S.-Canada 2009 Arctic Seafloor Continental Shelf Survey
Location: Beaufort Sea, north of the arctic circle
Date: September 5, 2009

Weather Data from the Bridge  
Latitude: 770 13’N
Longitude: 1370 41’W
Temperature: 290F

Science and Technology Log 

The two icebreakers are tying up side-by-side so that we can visit each other.
The two icebreakers are tying up side-by-side so that we can visit each other.

More Ways to Use Sound to See Beneath the Sea Floor 

Today we “rafted” with the Louis (the ships tied together side by side). I have been eager to see the science instruments that the Canadian ship is carrying. Once the ships were securely tied together we could just walk back and forth between them and tour the Canadian vessel.

The Healy has been breaking ice so that the Louis can have an easier time collecting data using seismic reflection profiling.  The goal is for the Canadian scientists to determine how deep the sediments are in this part of the Arctic Basin.  The sound waves their instrument sends out can penetrate about 1500 meters below the seafloor. Using sound they can “see” inside the earth – amazing!

FOR MY STUDENTS:  Remember your Latin/Greek word parts?  Look up “seism”. 

Seismic sled being hauled out of the water on the Louis. (Photo courtesy of Ethan Roth)
Seismic sled being hauled out of the water on the Louis. (Photo courtesy of Ethan Roth)

Here is how it works. The Louis steams forward at a low speed following in the path that the Healy has created through the ice. The Louis tows behind a weighted sled with 3 airguns suspended from the bottom.  This sinks about 10 meters below the water. Attached to the sled is a long tube filled with hydrophones (underwater microphones) called a streamer.  This streamer is about 400 meters long and stretches out behind the ship. It is best for the ship to move continuously so that the streamer will not sink or float to the surface.

FOR MY STUDENTS: Try to picture a 400-meter long “tail” on a ship. That is longer than 4 football fields. 

The airguns create a huge air bubble in the water.  When it collapses, it creates a sound pulse.  Two of the guns use a low frequency, which will penetrate deep into the sea floor but will create a low-resolution image.  The other gun uses a high frequency, which does not penetrate as deep but gives a high-resolution image.  The 16 sound recorders in the streamer record the echo created by these sounds reflecting from the sediment layers below the sea floor. The final product this instrument creates is an image of a cross section through the Earth. Scientists can look at these by observing this geologic history, the scientists are looking back in time. You can imagine that ice can cause lots of problems when a ship is towing a 400-meter long streamer behind it.  This is why we are working on collecting this data together.  One ship breaks, the other collects the seismic reflection data.

Steamer on deck of Louis. The blue steamer is out of the water and lying on deck when we visit the Louis.
Steamer on deck of Louis. The blue steamer is out of the water and lying on deck when we visit the Louis.

Personal Log 

The crew has been looking forward to the two ships tying up together for the entire cruise.  Everyone is curious about the other ship. What are the staterooms like?  What is the food like? How is their bridge different from our bridge? And of course there is shopping!! Both of the ship stores had their best Louis and Healy gear ready for the eager shoppers.

After learning about the science instruments aboard the Louis, it was nice to finally see the seismic sled, streamers, and the computer nerve center where the seismic images are received. The ships are pretty different in their appearance.  The Louis is an older vessel and has wooden handrails, panels cover the wires in the ceiling, and there are some larger windows with actual curtains.  The Healy was built to be a science research icebreaker and so has many large spaces for science and looks generally more industrial. The Louis was an icebreaker first and some of their science spaces have been added later and are less spacious.

The bubble created by the airguns on the Louis. (Photo Courtesy Pat Kelley USCG)
The bubble created by the airguns on the Louis. (Photo Courtesy
Pat Kelley USCG)

Shopping and tours were fun but the most anticipated events of the day were the evening meal, contests and games.  The ship’s officers exchanged gifts in a formal presentation and then we had an amazing buffet together.  Personnel from both ships enjoyed scallops, halibut, salmon, shrimp, lobster, pork, beef, cheese, salads, and desserts. This was an exceptional meal and a great social event.  The idea of having Teachers at Sea (TAS) was a new one for most Canadians I spoke with and as we talked they seemed to think this TAS would be a great idea to stimulate interest in young Canadians about maritime careers.  The evening concluded with some friendly competitions between the crews and the science parties.  This entire event was a lot of work for the Coast Guard crews.  The science party really appreciates all the hours they put into planning this event!

Behind the wheel on the bridge of the Louis S. St. Laurent.
Behind the wheel on the bridge of the Louis S. St. Laurent.

Jacquelyn Hams, August 9, 2006

NOAA Teacher at Sea
Jacquelyn Hams
Onboard NOAA Ship Rainier
July 24 – August 11, 2006

Mission: Hydrographic Survey
Geographical Area: Shumagin Islands, Alaska
Date: August 9, 2006

ENS Meghan McGovern on left, and ENS Olivia Hauser on right, RAINIER Junior Officers, looking at unmarked buoy sighted by officers on bridge of the RAINIER
ENS Meghan McGovern and ENS Olivia Hauser, Jr Officers, looking at unmarked buoy sighted on the bridge

Weather: Foggy, cloudy
Visibility: 1.5 nm
Wind direction: 130
Wind speed: 6 knots
Swell Waves direction: 260
Swell height: 1-2 ft
Seawater temperature: 11.7 degrees C
Sea level pressure: 1014,9 mb
Temperature dry bulb: 12.8 degrees C
Temperature wet bulb: 12.2 degrees C

Personal Log 

I continue to work on activities that can be incorporated into my classes.  The RAINIER is underway to Seward, Alaska. There is some excitement on the bridge after lunch, when an unmarked buoy is sighted on the port side of the ship. Several officers come to the bridge to observe and the buoy is marked on the chart.  As it turns out, this is not a “find” and was updated on the Notice to Mariners put out by NOAA.

After dinner, fog moves in and the RAINIER sounds the fog horn.  As a sailor, I don’t like fog. I am comforted by the fact that I am aboard a large ship with good radar system to detect approaching ships. The fog begins to lift a little and the last day of the cruise, like the first day, is marked by seeing humpback whales.

If this had truly been a “find”, the buoy would have been penciled in and added by NOAA.
If this had truly been a “find”, the buoy would have been penciled in and added by NOAA.

Jacquelyn Hams, August 8, 2006

NOAA Teacher at Sea
Jacquelyn Hams
Onboard NOAA Ship Rainier
July 24 – August 11, 2006

Mission: Hydrographic Survey
Geographical Area: Shumagin Islands, Alaska
Date: August 8, 2006

Cloudy Visibility: 6 nm
Wind direction: Light
Wind speed: AIRS
Wave direction: 200
Swell height: 2-3ft.
Seawater temperature: 8.9 degrees C
Sea level pressure: 1018.0 mb
Temperature dry bulb: 12.2 degrees C
Temperature wet bulb: 12.2 degrees C

Personal Log

We are anchored in East Bight and I continue to work on lesson plans. We are scheduled to get underway today for Seward. I am excited because I can spend two days in Seward seeing glaciers and fjords. Although, the weather has changed and it is cloudy and overcast, there is an up side to the weather. Geologic features that are often obscure when the sun is shining show up when the weather is overcast and more contrast is provided. I take the opportunity to showcase another basic geologic feature that is well exposed.

Here is a scenic view of part of the Shumagin Islands.  The Haystacks formation is in the center of the photograph.
A scenic view of part of the Shumagin Islands and the Haystacks formation

This is a type of drainage pattern is known as radial.  The drainage originates from a central point and occurs on elevated features such as volcanoes.
This is a type of drainage pattern is known as radial. The drainage originates from a central point and occurs on elevated features such as volcanoes.

Jacquelyn Hams, August 7, 2006

NOAA Teacher at Sea
Jacquelyn Hams
Onboard NOAA Ship Rainier
July 24 – August 11, 2006

Mission: Hydrographic Survey
Geographical Area: Shumagin Islands, Alaska
Date: August 7, 2006

TAS Jacquelyn Hams using a sextant
TAS Jacquelyn Hams using a sextant

Clear Visibility: 10 nm
Wind direction: 290
Wind speed: 6 knots
Seawater temperature: 10.6 degrees C
Sea level pressure: 1020.5 mb
Temperature dry bulb: 15.6 degrees C
Temperature wet bulb: 12.8 degrees C

Personal Log 

We are anchored in East Bight and I continue to work on lesson plans.  It is a beautiful clear day with many great photo opportunities.  I take advantage of the expertise of Intern Umeko Foster, who gives me a crash course in using the sextant.  I reluctantly admit to owning a sextant for many years and not using it to navigate. Umeko is an excellent teacher and for the first time I am able successfully move the sun to the correct position on the horizon! As a bonus, Umeko demonstrates the correct way to read degrees and minutes.  After dinner, Able Seaman Leslie Abramson drives the liberty boat to and from the beach so crew members can enjoy a little r and r. I ask Leslie to take me on a cruise to a nearby outcrop of rocks with many geologic structures.

Geologic structures are everywhere in this outcrop.  Save this picture to your desktop and enlarge it.  How many faults, dikes, sills, and folds do see?
Geologic structures are everywhere in this outcrop. Save this picture to your desktop and enlarge it. How many faults, dikes, sills, and folds do see?

Jacquelyn Hams, August 6, 2006

NOAA Teacher at Sea
Jacquelyn Hams
Onboard NOAA Ship Rainier
July 24 – August 11, 2006

Mission: Hydrographic Survey
Geographical Area: Shumagin Islands, Alaska
Date: August 6, 2006

TAS Jacquelyn Hams uses a lead line to determine depth during a shoreline survey
TAS Jacquelyn Hams uses a lead line to determine depth during a shoreline survey

Cloudy Visibility: 10 nm
Wind direction: Light
Wind speed: AIRS
Swell Waves direction: 350
Swell height: 0-1
Seawater temperature: 10.0 degrees C
Sea level pressure: 1018.5 mb
Temperature dry bulb: 15.0 degrees C
Temperature wet bulb: 12.2 degrees C

Science and Technology Log 

Today I go out on a small boat with Jim Jacobson, Chief Survey Technician, ENS Megan McGovern, RAINIER Junior Officer, Erin Campbell, Survey Technician, and Corey Muzzy, Seaman Surveyor and Coxswain to conduct a shoreline survey in Porpoise Harbor.  The objective of the shoreline survey is to verify some points which were identified by LIDAR (Airborne laser mapping) which may or may not be rocks along the shoreline. LIDAR is an emerging remote sensing technology that integrates the following three subsystems in to a single instrument mounted in a small airplane to rapidly produce accurate maps of the terrain beneath the flight path of the aircraft.

  • LIDAR (LIght Detection And Ranging) is similar to radar or sonar in that it transmits laser pulses to a target and records the time it takes for the pulse to return to the sensor receiver
  • Fixed reference systems
  • Global positioning satellite system (GPS).

Bathymetric chart reflecting points for investigation during shoreline survey
Bathymetric chart reflecting points for investigation during shoreline survey

LIDAR utilizes a pulsed laser rangefinder mounted in the aircraft.  While most LIDAR systems are designed to measure land elevations (“topographic LIDAR”), the technology can also measure water depths if designed with a light wavelength which will pass through water (“bathymetric LIDAR”).  Bathymetric LIDAR accurately measures the travel time for both the laser return from the sea surface and the return from the seabed.   If the speed of light is known and one corrects for angle, scattering, absorption at the water surface and other biases, the distance to the sea surface and seabed can be computed from these times.  The difference between these distances is the water depth.  In general, bathymetric LIDAR is less accurate and lower resolution than the multibeam sonar systems on RAINIER’s launches, but it can be much faster and safer in some areas.

This is a picture of a sonar image taken on the boat during shoreline survey. The spike on the image represents a rock.
This is a picture of a sonar image taken on the boat. The spike on the image represents a rock.

We have several LIDAR points to verify. RAINIER has been asked to investigate these points because they are around kelp which LIDAR cannot penetrate.  The boat is equipped with vertical beam echo sounders so that the bottom depth is known.  Once the boat reaches the point of investigation, the coxswain drives a star pattern around the point to make sure that all sides of the potential obstacle have been covered.  Lead lines are used to confirm depths close to the shoreline.

The presence of a rock is indicated by the peak in the sonar image on the left.  Depth of the recorder is 32.4 feet. We are able to survey all but three of our points until we have engine problems after crossing on the edge of a thick patch of kelp. Unfortunately, the engine will not start and we have to call for a tow. On the way back to the ship, I have yet another photo opportunity for some geology pictures.  Nagai Island lies within a major fault zone of the Aleutian Islands so many of the rocks are folded and uplifted into spectacular structures. The beds pictured in the photograph below were deposited according to the Principle of Original Horizontality; therefore they should be stacked on top of each other in a horizontal position. Look at them now!

ENS Megan McGovern, RAINIER Junior Office and Leslie Abramson, Able Seaman.
ENS Megan McGovern, RAINIER Junior Office and Leslie Abramson, Able Seaman.

Imagine the stress that tilted these beds to the current position.
Imagine the stress that tilted these beds to the current position.