Lamont Doherty Observatory Essays - Columbia University,

Lamont Doherty Observatory Every year the Lamont ? Doherty Earth Observatory holds an open house in which scientists share their studies and really let the public see what and how they do what they do. Scientists at this research center are working together studying different fields of the Geologic sciences ranging from Oceanography, Geochemistry, Seismology, and even Marine Biology share their findings with the public. This year like every other year, they set up deferent exhibits and share the current research, studies and illustrations of the different Geologic processes along with their findings with anybody who is interested. For this assignment, we were asked to describe five of the exhibits from the LDEO open house. The five exhibits that called my attention the most were the Seismology, Geochemistry, Oceanography, Demonstration of Hard and Soft behavior of the surface of our, and the "Water Current Exhibit". 1- Seismology in simple terms is the study of earthquakes; it involves observations of natural ground vibrations and artificial vibrations. In this exhibit, the scientists were explaining how and earthquake forms and how it can be detected even hundreds of miles away via a Seismograph. Someone asked the question what is an earthquake. And the response was "well, it's a trembling or shaking of the ground causes by a sudden release of energy, energy that is stored in the rocks beneath the surface". I thought that was great so then, I asked how is this energy stored? And his explanation was very well illustrated by a simple demonstration. There sere two bricks joined together by a rubber band, at the end of the first brick there was a nylon thread which was being pulled slowly. He said imagine these two bricks are two plates floating on the mantle, as one moves slowly, it is"pulling" the rubber band that is attached to the other brick and tension is building over time then very sudden and quickly the rubber band pulls the brick behind it, and this is how the energy builds up and then it is released quickly. (Drawing of bricks) Then he had a Seismograph, a device that measures seismic waves on a table and he was explaining how to read the intensity of the vibrations. He had first one kid jumping in front of he seismograph, then two, then three, then four and so one and one could see the intensity of the vibrations being recorded by the seismograph. He also talked about the use of seismic stations all over to monitors earthquakes and artificial vibrations like explosions, etc. The Seismology department at LDEO monitors seismic activity in the Northeast region of the US; here is a map of the location of those seismographic stations. 2- Geochemistry is the applications of chemical principles and techniques to geologic studies to help us understand how chemical elements are distributed in the crust mantle and core of the earth. Geologists have many ways of gathering data for this kind of study, one of them is of course by taking samples and analyzing them, but in one of the labs at LDEO I saw something I thought was very interesting. Scientists want to know how a mineral of a given chemical composition behaves under extreme heat and pressure such as those found deep within the earth, but because they can not drill that deep to take samples, they came up with the idea of building a press that could replicate specific pressures and temperatures pretty much like those found deep within the earth. The press is relatively simple; it uses hydraulic power to generate the pressure and a special heater to generate tremendous amounts of heat, as much as 3000 degrees centigrade. This press uses anvels that press the sample from eight different directions thus increasing and redirecting the pressure exherted by the hydraulic press. By heating and pressuring the samples, they are able to study the chemical and crystal structure of different samples. The demonstration he gave was with a brass ball which he put inside the press, put the amvels on top and then pressured it just for a brief moment and the result was a ball with eight flat surfaces. I thought this was so interesting that I had to have the brass ball. 3- Deep Sea Sample Repository. The LDEO has an archive of sediment and rock from the beneath the ocean floor. This material is used for studies in oceanography, and marine geology. Most of the core samples are from the Atlantic Ocean, and during the open house, scientists took the