Instructions: Follow the instructions in this exercise and answer all questions either on a blank sheet of paper or directly on the question sheet, which you must print out. To access the Web sites listed below, click on the links given in this exercise. NOTE: Clicking a link opens the page in a new window. The purpose of this exercise is to explore the topic of mineral resources including hydrothermal vents, which represent a model for sulfide mineral ore deposits produced by black smokers and borate minerals.
The purpose of this part is to learn about hydrothermal vents in
the ocean floor at the Dive and Discover Web site, sponsored by
Woods Hole Oceanographic Institution, a private, independent,
not-for-profit corporation dedicated to ocean science research.
Hydrothermal vents commonly contain rich concentrations of sulfide
ore minerals (Fe-, Cu-, Zn-, and Mn-sulfides that can be
economically valuable) and they are considered a model for the
origin of ancient massive sulfide ore deposits found on
Go to the Dive and Discover: Hydrothermal Vents Web site at: <http://divediscover.whoi.edu/vents/index.html>
on this page. Then, click on the link Vent Basics located
on the left side in the blue column area under the heading The
Basics. The direct URL is <http://divediscover.whoi.edu/vents/basics.html>.
Read the information on this page including the text that
appears on the black smoker figure when you click on active
links, especially the circled numbers 1 - 4 and the
terms Black smoker and Chimney.
Next, click on the link Videos located on the left side
in the blue column area under the heading Extras. The
direct URL is <http://divediscover.whoi.edu/vents/video.html>.
this page; one shows a black smoker and the other shows vent
Finally, to see where hydrothermal vents have been found around
the world, click on the link Vents around the World
located on the left side in the blue column area under the heading
The Basics. The direct URL is <http://divediscover.whoi.edu/vents/world.html>.
this page and then answer the first question.
(1) Summarize the basics of hydrothermal vents as well as black
smokers and chimneys by answering the three questions below.
(a) Define hydrothermal vents, black smokers, and chimneys. (1.5
(b) Where and how do hydrothermal vents, black smokers and
chimneys form? (1 pt)
(c) What is the source of the smoke in black smokers? (0.5 pts)
Next, click on the link Vent Boiling Points located on the left side in the blue column area under the heading The Basics. The direct URL is <http://divediscover.whoi.edu/vents/boiling.html>. Read the information on this page including the water boiling temperatures that appear on the figure when you click on the six question marks in red circles at different ocean depths.
Also, go the the following Web pages and read about the different
depths that underwater research vessels can go as well as the
pressure at several depths in the ocean.
You will need to click on the different depth values to get specific information about that ocean depth. All of this information is relevant to the extraordinary temperatures of the fluids at hydrothermal vents.
(2) (a) What happens to the pressure of water with increasing depth in the ocean? (0.5 pts)
(b) What happens to the boiling point of water with increasing depth in the ocean? Explain your answer. (0.5 pts)
Next, click on the following link:
Read the information on this page including the information that appears below the hydrothermal vent figure when you click on the circled numbers 1 - 8.
(3) How do hydrothermal vents affect the chemical composition of
seawater? Give specific examples of elements that are affected by
processes at hydrothermal vents. (1 pt)
Next, learn about Vent Biology by clicking on the links Vent Life, Tubeworm Anatomy, and Chemosynthesis located on the left side in the blue column area under the heading Vent Biology. The direct URLs are:
Read the information on these pages including information that
appears when you click on the active links on each page.
(4) Explain the term chemosynthesis and why it is important to
organisms that live near vents, i.e., vent biology. (1 pt)
Boron is one of the lightest elements (atomic number = 5) and in nature always occurs with oxygen as borate (one or more boron atoms with two or more oxygen atoms). There are more than 150 known borate minerals but only 4 or 5 are economically important.
Rio Tinto is the parent company for Rio Tinto Borates and Borax,
which are the world's largest supplier of refined borate minerals.
Rio Tinto Borates operates one of the world's largest borate mine
in the Mojave Desert near Boron, CA. View pictures of this borate
deposit and read about its geologic origin at:
(5) Describe how the borate deposits in the Mojave Desert formed. In particular, make sure to state whether the borate deposits are in sedimentary, igneous or metamorphic rock; in what specific rock the borate deposits are located; and how the rock became rich in Boron. (1 pt)
Now, go to the homepage of 20 Mule Team Borax (part of Rio Tinto Borates): <http://www.borax.com>. Under the pull-down menu Borates, select Borates by function and read the information on this page. The direct URL is <http://www.borax.com/borates-2/borates-by-function/>
(6) List and give a brief (few word) description of the twelve
functions of borates, which make them useful to society. (2 pts)
Under the same pull-down menu Borates, select Borates
in use and read the information on this page. The direct URL
(7) List the top four uses of borate minerals as well as three other uses. (0.5 pts)
Now, go to a Wikipedia site on borate minerals to view the most
common borate minerals listed at the top of the page:
(8) The five borate minerals at the top of this page are the
major borate ore minerals. List these 5 minerals giving both the
borate mineral name and its structural formula. (0.5 pts)
NOTE: One of these borate minerals (Ulexite) is also nicknamed "TV rock" because it can transmit light similar to fiber optics (transmitting an image from one side of the mineral specimen to the other!). Check out the links showing this property!!