In grade school, everyone is taught that a meteorite killed the dinosaurs. The “Alvarez Hypothesis” posits that a large asteroid hit the Earth 65 million years ago. Its impact caused a large tsunami and threw dust into the atmosphere that blocked the Sun for an extended period of time. This caused photosynthetic failure, and the food chain collapsed.
It all began in the late 1970s when geologist Walter Alvarez sampled a layer at the Cretaceous-Paleogene (K-Pg) boundary. His father Luis Alvarez — a Nobel Prize winning physicist — helped him analyze the samples for various metals. They found a spike in iridium at the time of the K-Pg extinction. Iridium is rare in the Earth’s crust but abundant in meteorites. In 1980, they proposed their hypothesis that a meteorite was responsible for the dinosaurs’ demise. Ten years later, geologists found an impact crater in Chixulub, Mexico that matched the description of the hypothesized rock.
But many scientists at that time were skeptical of their findings. Another plausible hypothesis was that the Deccan Traps — a series of large volcanoes in India — erupted shortly before the K-Pg boundary, causing climatic changes that ultimately created a mass extinction. The evidence at that time for this hypothesis consisted of the facts that various species had already been in decline for thousands of years prior to the K-Pg boundary and carbon-13 isotopes indicated global warming that shifted to abrupt cooling at the start of the Paleogene.
My professor — Gerta Keller — started her research in this field nearly thirty years ago. As the number of supporters for Deccan volcanism dwindled from new evidence and bullying from other scientists, she stood firm in her belief that volcanism killed the dinosaurs. One of her biggest contributions to the debate was finding glass spherules several meters below the K-Pg boundary at an outcrop in Mexico. Supporters of the Alvarez hypothesis claim that these spherules are crystallized ejecta that rained down shortly after the meteorite’s impact. Their newfound placement means that the asteroid impact may have preceded the boundary by as much as 300,000 years. Additionally, recent research spearheaded by Keller and another Princeton geologist shows that Deccan volcanism correlates more closely in time to the K-Pg boundary than previously thought.
This debate — along with the study of Earth’s other four mass extinctions — is the topic for my class GEO 365. Last week, we traveled to Morocco to learn more about mass extinctions and the planet’s natural history.
Day 1— I lined up with my class on Ivy Lane at 14:00 to wait for our bus to the JFK airport. Once onboard, we rocketed to New York City. By 21:00, our flight had departed for Casablanca, Morocco.
Day 2— I could hardly sleep on the airplane, but I awoke to see Morocco’s brown desert. We landed in a thick fog that prevented us from seeing further than twenty feet. As we stepped off of the airplane, the air was hardly 60ºF. But the Sun quickly warmed it. Our guides — Khalid and Thierry Adatte— loaded our luggage into a van, and we traveled southward. Thierry was a Swiss member of Professor Keller’s original K-Pg research team.
The land was barren with brown soil covering rolling hills. But even the soil disappeared and was replaced by rocks the further south we went. There were few trees. Everyone fell asleep. I briefly awoke during the drive through the Meseta — a plain between the Atlantic coast and Atlas Mountains — to see the flat desert pavement stretch to the horizon in all directions.
We stopped at an outcrop near Marrakech, one of Morocco’s largest cities. Thierry gave us an hourlong overview of the Atlas Mountains’ formation. In short, they are the product of failed rifting (Liassic), Africa colliding with Iberian peninsula (Early Cretaceous), Africa pulling away from South America (Mid-Cretaceous), continental uplifting from moving towards Eurasia (Santonian), and three compressional events with Africa-Europe convergence (Eocene).
As I scanned the area, I noticed a mesa in the distance. The landscape reminded me of the American southwest. Throughout the day, we continued to stop on the roadside to look at rocks. We slept in between the stops. Many of the roads have steep plunges with no guardrails along their sides as they wind up the mountainsides.
The Atlas Mountains were barren. They were colored with a variety of dark reds, yellows, and browns. We never crossed a river while driving through them.
The bus passed several villages. All of the buildings are square, and the mosque’s minaret is the tallest structure in each locale.
We stopped for the night at a hotel in Ouarzazate.
Dinner: chicken tajine dish (chicken and steamed vegetables)
Day 3 — We left the hotel and took pictures at a pyramidal building. Ouarzazate is known as the “door of the desert.” Directors frequently use it to cast desert scenes because of its convenient location. These include: Lawrence of Arabia, Gladiator, Kingdom of Heaven, and Game of Thrones.
On the outskirts of town, we stopped to learn about foreland basins. As Thierry was delivering a lecture, a herd of goats walked around us. Next, we made an excursion to the Dadès Gorge where we studied the emplacement of conglomerates.
Our following stop was at a small valley. To get there, two thirds of the class piled into a small SUV. The other six, including myself, had to stand on the car’s running boards. After driving two kilometers, we stopped to look at dinosaur tracks. They were over two feet long. The valley looked like a set for Tatooine from Star Wars. I was waiting for some Tusken Raiders to jump out from behind a rock.
We then went to another section of the Dadès Gorge. To reach it, we drove up steep switchbacks. Its step-like walls plunged three thousand feet into a river below. A hotel sat on the precipice’s edge at the top. It looked like it would teeter over the edge at any minute.
While continuing southward, we observed a conglomerate rock formation. It was exotic. The red rock had a bubble pattern that made it look like the remnant of some big splash. In reality, it was created as a result of the conglomerate’s unique erosion pattern in wind and rain.
Our final stop was in Todra Gorge. Professor Keller told us that there was an old hotel in the canyon that previous classes had stayed in. She stopped going to it because a boulder from the canyon wall crushed its dining pavilion.
As the sun set, Thierry instructed our class to measure rock layers in the canyons. We worked into the dark and presented our results upon arrival at the hotel “Chez Aïche.” Following dinner, several of us went onto the hotel roof to look at the stars.
A dog barked at the Moon.
Breakfast: khobz, butter, yogurt
Lunch: khobz, peppers, onions, cheese
Dinner: beef tajine, dates
Day 4— The golden morning light basked the orange mountaintops against the cerulean sky. I hadn’t realized this at night, but the hotel was surrounded by mountains on all sides.
After breakfast, we drove to Jbel Ouarkziz (“jbel” means mountain). Thierry told us to look at the rocks and determine the area’s paleoenvironment. Although I worked on the marine layers at Zumaia, Spain this spring, I had forgotten a few things. As I was studying the rocks, I overlooked the turbidites cutting through the ridge. They indicated that the area was once on the submarine continental slope.
From the top of the hill, I saw the Anti-Atlas Mountains in the distance. Some of its closer hills appeared as though their sides were sheered off, exposing their complex folds. Everything was brown.
Back on the road, we stopped to look at a series of ten-foot tall mounds. They were holes into the ground that were used to dig tunnels. In Medieval times, townspeople created them to transport water from the Anti-Atlas Mountains. People had been using them until thirty years ago.
Our last stop of the day was at an outcrop outside of a town. We searched for the black shale that denoted the end-Devonian mass extinction. Each shale layer represented one Kellwasser Event, an extinction pulse. Nobody could find them, so Thierry finally showed us.
Some kids were fishing at a nearby stream. They tried to sell us a fish that they had caught and put in a water bottle.
We ended the day at a hotel near Merzouga. There was a large sand desert, called Erg Chebbi, adjacent to it. It was the first desert that I saw that looked like what I had pictured. Classical orange Saharan sand dunes towered over the dry pavement around them. Some Berbers mounted us on camels, and we rode into the desert.
As the Sun set over the Anti-Atlas Mountains, the dunes blazed brightly. When it finally disappeared behind the parks, the sky turned a deep azure. The novelty of riding a camel wore off in ten minutes; it hurt to ride bow-legged.
We arrived at a prearranged camp and moved into nomad tents, which were made of thick green and red cloths. Dinner was not served for two hours. In the meantime, a classmate played the drums and another told a joke story.
After dinner, I went with another student to the top of a nearby dune to take night pictures. Others soon joined us. The Moon was a spotlight. I could practically read a book under it. Stars blazed fiercely into the black sky. We returned to camp where the Berbers had built a campfire. They taught us some of their traditional dances.
I, along with a few others, slept out under the stars with only a mat and blanket. The cool desert air descended onto the camp.
Breakfast: eggs, bread, butter, jelly, tea
Lunch: khobz, tuna, cheese, avocado
Dinner: tomato and chickpea salad, chicken tajine, dates, tea.
I have never really like tea. But I started drinking the Moroccan tea on this trip out of courtesy. It was served with almost every meal. Eventually, I came to like it.
Day 5— I became cold in the night and woke up around 4:00. The Moon had set, so the sky was darker. But I could still see even without a flashlight. I realized my good fortune and decided to take pictures of the night sky. Everyone else arose at 5:30, departing at 6:00 to watch the Sun rise.
Back at the hotel, we ate breakfast and then left to continue our geological tour. The first stop was Hamar Lackhad Ridge. We had to ride on the outside of the SUV again to reach it. We hiked up a valley that had a strange set of mounds that were ~100 feet tall scattered around it. The ridge was composed of seafloor from the Ordovician period. Thierry explained that scientists had determined that the mounds were once underwater mud volcanoes driven by geothermal heat. We hiked to the top of one of these mounds, called a “kess-kess.” At the summit, I saw the expansive plain. There was nothing but brown desert.
We descended to study a fault line. Then, we looked for fossils near the ridge’s base. After lunch, we stopped in a trilobite fossil shop. Next, we looked for our own trilobites near Jbel Mani as the Moon rose over its peaks. I found a few pieces but nothing spectacular.
Breakfast: khobz, muffin, yogurt
Lunch: khobz, tuna, avocado, cheese
Dinner: khobz, lentil soup, chicken tagine, banana
Day 6— We left our hotel to eat breakfast in a nearby restaurant. Our first stop after that was at a wide gorge. Its walls were composed of alternating limestone and shale layers. While driving to the next location, we traveled to a mining district to see ophiolites. Foreigners were not permitted to see the mine. Thierry explained that the people were unhealthy, and there were reports of children being used for dangerous work.
After lunch, we observed a spectacular volcanic dyke that was part of the Central Atlantic Magmatic Province, the likely cause of the end-Triassic mass extinction. As we drove closer to it, I watched dust devils dance around the valley. Some of them were 100 meters wide.
We ended the day near a small town that was adjacent to a river oasis. The river had cut a canyon in as little as 8,000 years. To my back, the Moon rose over an ancient Ordovician ridge.
That night, we stayed in the hotel La Renaissance at the edge of the Saharan Desert. Thierry told us that the next major town was Timbuktu, over 1,500 kilometers to the south in Mali.
Breakfast— khobz, butter, orange juice
Lunch: khobz, onions, tuna, cheese, avocado
Dinner: beef tajine, lentil soup, khobz, orange soda
Day 7— Two students were sick from dinner. Everyone else was fine. The first stop was at an Ordovician range several miles from town. We hiked back into a valley to study Cambrian-aged alternating limestone and shale layers. Thierry said that they were deposits from extreme tides and storms. One student did not believe it and fiercely questioned him. Thierry then explained that the layers’ alternations showed Milankovitch cyclicality. I remained skeptical of this considering my group’s findings in Zumaia.
While we were in the valley, a man approached us from the direction that we had just came. I have no idea how he got there. It was a long walk from the town. He asked several times if we had marijuana. We said no. Then he walked up into the mountains.
The rest of our day comprised primarily of driving westward to the coast by Tiznit. Western Morocco is more verdant than its interior. It looked like the Mediterranean coast. Once at the ocean, we walked along the beach and under a sea arch. Later that night, I went back to the beach to take sky pictures.
Breakfast: khobz, butter, orange juice
Lunch: khobz, cheese
Dinner: khobz, chickpea soup, grilled fish, rice, boiled vegetables, apple slices, cake
Day 8— I walked around the beach in the morning. When I approached a rock outcrop jutting into the ocean, I saw a stray puppy jumping around. It spotted me, and, yipping from the cold, followed me back to the steps of the hotel, Club Auberge. The parent dogs spotted me and then ran over to care for the puppy. But it followed me up the hotel steps and stayed under the table as we ate breakfast.
The road northward snaked along the coast with spectacular ocean overlooks. After traveling for a week through the desert, it was good to see water. By midday, we stopped onto of a big hill near Agadir. The city is a big tourist destination. Thierry taught us about an earthquake that struck Agadir in 1960. For decades, people didn’t build on top of the fault. But a construction project recently placed condominiums on it. The fault is still active. Another earthquake could strike Agadir any day.
Just north of the city, we passed a white walled compound on the coast. Thierry explained that it was owned by a brother of the King of Saudi Arabia. One of the other brothers became jealous and built an even larger tan walled vacation compound a mere 200 meters north of it. There used to be a cement factory near the compounds, but they forced it to close and move 100 kilometers inland.
Next, we walked along a cliff on a beach to look at a past oceanic anoxic event — meaning that oxygen levels in the ocean were low — from the Cretaceous. It reminded me of Zumaia because of its alternating limestone and marl layers. When Thierry finished his final lesson, everyone applauded. As we walked back to the car, the Sun lowered towards the horizon.
By nautical twilight, we were at another beach, looking a small set of dinosaur tracks. Our hotel for the night, Hotel Littoral, was fantastic. We were placed in a small apartment. After dinner, Khalid brought us three homemade cakes.
Breakfast: khobz, butter, pan au chocolat, orange juice
Lunch: khobz, avocado, cheese
Dinner: sausage, couscous, chicken, khobz, and chocolate, coconut, and apple cakes
Day 9— Our trek continued northward from Agadir after breakfast. The black tarmac followed the coast, passing a tall white lighthouse. Then, it headed inland. At one point, we stopped along the road to look at some goats in a tree. They eat their Argania fruits. Then, shepherds harvest the fruit’s seeds from the goats’ droppings, and it is turned into argan oil.
At noon, we rested in Essaouira and walked around. The old part of the city is in an old Portuguese trading fort. It’s very touristy with a lot of Europeans. I walked around with some friends for some time before eating lunch on a restaurant’s balcony. Around 14:30, we continued onward to Marrakech.
Before arriving in the city, we stopped in a cooperative where divorced women make argan oil. They showed us all of the steps to making it and the oil’s various uses.
As we entered Marrakech, there was a well-developed strip of high end hotels and resorts. We didn’t stay there. Instead, we stayed in the Grand Hotel Taziz near the city’s center. Professor Keller said that it was a dive hotel from her backpacking trip across northern Africa in the 1970s.
“Dive” was an accurate description. All of the guys stayed in a single room with five mattresses. Located on the roof, our room had half inch deep holes in the wall, light pink blankets, lightbulbs hanging out of the walls, red and white striped drapes, black and white checkerboard flooring, a loop of wire hanging out of the ceiling, a moldy shower, and vomit in the toilet when we first arrived. The rooms’ door handle was barely hanging by a screw. Instead of having a glass peephole, our door had a one-inch diameter hole drilled into it. Morocco doesn’t have too much gun crime due to strict ownership laws, but one of the country’s few shootings occurred in the area during the previous week.
Our group then went to Morocco’s largest open air market, called a “souk.” The streets were swarmed with people. It was intense. After dinner, we went shopping in the market. Most of the goods were cheap Chinese junk. I went with a friend to the souk’s center to watch him buy a pair of fake Nike shoes. I noticed that the store owner was not very interested in negotiating. At that moment, I noticed that several people were glued to a television screen. Casablanca’s soccer team was playing Cairo for the African championship. Two minutes later, the square erupted into cheering. Casablanca won.
Later that night, I went onto the hotel’s roof to take pictures with another student. Cars drove through the square while honking horns and waving Moroccan flags to celebrate the soccer victory. A horde of 50 motorcycles even crowded the intersection as they drove around town in their quasi-victory parade.
Breakfast: khobz, jam, butter, cake
Lunch: cheese omelette
Dinner: chicken kabob, fries
Dessert: crêpe with Nutella
Day 10— We awoke at 5:00 to leave for our flight. The streets — which had been filled by an open air market only a few hours earlier — were dead. Everyone slept on the drive to Casablanca. I stayed awake to watch the sun rise over the horizon of the Meseta.
Our bus stopped at a gas station for breakfast. While we were eating, one student said that there was a rat under the table. A gray rodent scrambled out into the aisle. Then, a worker punted it into the air, stomped on it, and kicked it out the door like a soccer ball.
We arrived at the airport and departed on time. The class arrived at Princeton by 20:30. I raced up to Nassau Street before the restaurants closed at 21:00 and ate at PJ’s. When I returned to my dorm, I immediately went to bed.
Breakfast: pan au chocolat, flatbread with Nutella
Lunch: grilled chicken sandwich, fries, chicken and rice, cake, bread
Dinner: hamburger, fries, chocolate milkshake
* * * * *
Morocco was a fascinating country. Its barren landscape was simple yet stunning. Its natural history goes back over a billion years, but people have just started to understand it during the past century. Our trip was a mere overview of its known record over the course of a week, barely a window of its entire story. One day, I hope to return and study it at greater depth.
A Typical Daily Schedule
- 6:30: Wake up
- 7:00-7:45: Breakfast
- 8:30-13:00: Geology touring
- 13:00: Lunch
- 13:30-19:00: Geology touring
- 19:00: Arrive at hotel
- 20:30: Dinner
- 21:30-0:00: Talk, play games, take pictures