Monday, December 17, 2012
Tuesday, January 17, 2012
This has been Dhiman’s first experience working with hard rock because Bangladesh only has loose, young sedimentary rocks. In Meghalaya, India we find extremely old metamorphic rocks - rocks that have been altered under high heat and pressure. We also find igneous rock called basalt that formed from molten rock (magma and lava), and sedimentary rocks such as sandstone and limestone. The sandstone here had millions of years to get compacted and cemented, and it’s so strong that it forms cliffs and giant waterfalls. Limestone is made of shells that have turned into rock.
What secrets can we learn from these rocks?
You remember one: we can learn how the Earth has folded using our compasses to measure the strike and dip! Once we put all our measurements on a map we can learn about the 3-D shape.
Antje’s also been collecting lots of samples of basalt (igneous rock), and she’ll process them in a paleomagnetics laboratory in order to learn about how the rocks have moved (remember that the Earth’s crust is made of plates that move around!). If you’ve ever used a compass, you probably know that Earth has a magnetic field. Magnetic minerals in rocks align with the magnetic field when they form, kind of like little compass needles. Since the Earth’s magnetic field doesn’t vary that much, we can figure out how the rock has moved and rotated since it formed by determining where the magnetic minerals point.
Unlike Bangladesh, Meghalaya has plenty of rocks exposed at the surface. The problem here is that the jungle makes them hard to find! We find the best outcrops along new roads and rivers. We have spent many days hiking through the canyons, climbing our way over huge boulders and getting our feet wet in search of outcrops. The rivers are at the bottom of deep canyons, so we often have to hike many thousands of steps to reach the water.
Friday, January 13, 2012
Thursday, January 12, 2012
The Sundarbans is the world’s largest mangrove forest. Literally, Sundarban means “beautifull forest”. The name is believed to be derived from a kind of tree which is said to be the main tree of this forest. Some believe that the name the name might come from “Somundor Bon” which is in English “Sea forest” because it lies beside the sea.
First of all, this is the land of the Royal Bengal Tiger. When we work in the forest, we usually do not want to meet a tiger though we have three forest guards with us. You probably know why. We are used to seeing the footprints and the skulls and bones of deer because tigers love deer for dinner. When they catch any deer they eat some meat, and then keep the deer in a secret place to be rotten, which is their favorite. As deer are available in the Bangladesh part of the forest, most of the 300 remaining tigers live in this part. About 60% of the total 10,000 sq.km of forest lies in Bangladesh, and the other 40% lies in India.
So, one question for you, “Do you want to see a Royal Bengal Tiger?” Write me why and why not.
Dhiman Ranjan Mondal
Senior Research Scientist
Dhaka University Earth Observatory
Department of Geology
University of Dhaka
Tuesday, January 10, 2012
Bangladesh is an extremely fertile land –the sediment from the Himalayas and the rain from the summer monsoon make food abundant. They can grow two crops of rice a year and grow vegetables like potatoes, beans, carrots, cabbage and squash during the winter. The rivers and ponds provide lots and lots of fish! The population of Bangladesh is growing rapidly and the Bangladeshi way of life is changing. People are leaving the rice paddies and fishing boats of their native villages behind and becoming business men, shopkeepers and cycle-rickshaw wallahs (see photo) in the city. These are hard-working people trying to find a better life for their families – a sentiment near and dear to our hearts in the USA!
What Bangladesh lacks is rock! The bedrock is many miles below the city so the buildings lack a firm foundation. Bangladeshi houses used to be made from straw and mud – which wouldn’t hurt you in an earthquake – but now they’re made of brick and concrete, which can crush you in an earthquake if they’re not reinforced enough!
Bricks are made from sand and mud (Bangladesh has plenty!) but need to be cooked. They burn coal to cook the bricks, but Bangladesh must import this coal from India. Limestone is a key ingredient for cement, and Bangladesh must also import this from India. The photo shows girls walking to school near a cement factory. This is leading to destruction of the environment in the highlands of Meghalaya, India and the rivers that carry rocks into Bangladesh. The beautiful landscape is being torn apart to provide limestone, coal and hard rock for construction in Bangladesh. This provides jobs for people, but they require back-breaking labor for very little pay. A man working in a quarry told us that hundreds of people have been killed by falling rock. We’ve seen many children doing work like hauling rocks on their heads and shoveling coal into trucks when they should be in school.
The photos above show a lime kiln where they cook the limestone before making cement; a boy who works all day shoveling coal; trucks transporting coal from India to Bangladesh.
There is no easy solution to these environmental and social issues, but birth control would help. Some families have 10 or more children, and it becomes impossible for the mother and father to feed them all with only one or two incomes. Planned urban development would make construction safer and improve city services like garbage collection. The cities are not equipped to deal with the garbage produced by the now-massive population. People throw rubbish in the street and it makes the cities very dirty. Industries like tourism can provide jobs without so much damage to the environment, but few people will want to visit the country if they can’t get the garbage under control!
Can you think of any other solutions to these problems?
We flew into Dhaka (the capital of Bangladesh) and drove through the city but didn’t stay there this time. I spent a few days there last year. It’s the 9th largest city in the world, with more than 16 million people. It’s also the fastest growing city in the world, with people from the countryside flocking to the city for work. There is no urban planning and no earthquake construction regulations, so we are very worried that an earthquake will be absolutely catastrophic (and you remember that Bangladesh sits between two big plate boundaries where major earthquakes happen!). Dhaka is very crowded and the traffic is unbelievably bad! This picture shows a pretty normal looking bus in Dhaka – all beaten up because nobody obeys any lane markings.
Very pleasant, 50-70 degrees. At night it’s comfortable with a light blanket and the ceiling fan on low. It rained one day which made us a little soggy, but it cleared the dust from the air!
7. Do you get homesick or miss the life back here in NYC? –Joanna
Since I went away to boarding school when I was 14, I had to learn how to cope with homesickness. I immerse myself in the moment and do not give myself time to dwell on sad or lonely thoughts. I do miss my boyfriend and our cats!
8. Where are you finding internet connection? –Bielka
9. Do you bring food with you in the field or is it provided? –Saratt
We usually eat a big breakfast and have some snacks in the afternoon. Sometimes we sit down for lunch at a small restaurant if we’re feeling hungry, but that takes time so we try to keep working! For breakfast we eat a type of flat bread called “Roti”, eggs made into a ‘momlette (as they call it in Bangladesh), and mixed vegetable curry. It is very, very tasty!
4- How long before your research is complete? –James
Well, this fieldwork will be done on the Jan 31st. I hope to be done with my PhD in 4 years. I have a lot more work to do in the field and in the lab, as well as writing papers and my dissertation.
5- How will your research change the scientific community? –RandyStudying the Shillong Plateau will improve our understanding of how the Dauki fault deforms the earth and what sort of earthquakes it can generate. It will also add to our knowledge about how rock folds at shallow depths where it’s not very hot. I really hope my research can help raise awareness about the earthquake hazards facing Bangladesh.
Sunday, January 8, 2012
On Sunday while Nano, Antje and I were collecting some samples of grey mudstone, Cecilia and Khaled went to explore around the other side of the hill. They found a wall of crumbly sandstone that had been cut to make room for a driveway. Khaled scraped away some of the grime covering the surface and what he found was amazing: bright orange sandstone with mudstone layers – it looked like tiger stripes!
But even more exciting was a diagonal band with broken up pieces of the mudstone that cuts straight through the flat layers – this might have been caused by violent shaking in an ancient earthquake!
We took lots of measurements, collected samples and took many, many photos so we can try to understand how an earthquake causes this kind of damage. Cecilia and Khaled will be heading to southern Bangladesh tomorrow to continue looking for damage caused by ancient earthquakes. We’ll miss them, but can’t wait to hear about what they find!
Later in the day on Sunday, we found some good rock outcrops near the Cricket stadium, and we climbed up to the top to get a good view. We found that the rocks lay flat, so we knew were standing on top of the middle of the anticline.
There were some little boys playing outside and they saw us way up on top of the hill and came to investigate. You can probably imagine how much we stand out – such strange foreign girls, dressed like men! We rarely see people here with closed shoes, let alone boots! As we continued working, more and more young children kept coming up the hill to join their friends.
Oh, and I almost forgot to mention we saw an elephant! (not wild, though.)