Dear visitor,
Welcome to my personal website. On this site you
will find some information on my PhD research, which I started on 1 november 2005. The site also is meant to
be readable by non-geologists, and thus contains some general
information on geology. Of course there is already a great number of websites
(and books) containing this kind of information, however to obtain this
information one needs to get interested, search for, and read
these web pages or books. I often meet people (e.g. friends,
family, etc.) who do not know what geology is about. So, this general
information is primarily meant to reach those people (who know me) who
otherwise probably would not look into the subject.
Introduction
Geology is the science that deals with how the earth is
formed. By looking at the rocks geologists try to unravel the history
of the earth. My opinion is that geology concerns us all.
Why? If we think
carefully, we need material to build houses and to warm them, to build
cars and to drive them, to build phones and to call with them. As far
as I know all this material comes from the earth. I have never heard of
houses build of meteorites and I also do not see (yet?) trucks driving
to and from Mars to get material to build houses. Of course we can
build and warm our houses with trees. But trees have their roots in the
earth. Vegetation is partly determined by the earth in which it grows.
Processes in the earth are all interconnected which makes it very
interesting, I think.
To continue, we use coal, gas, oil, metals for all our basic needs.
Yes, for food you need to hunt, to hunt you need weapons, for weapons
you need material from the earth. Remember in prehistoric times they
used flintstones, because they could be made very sharp due to their
hardness. This is already basic application of geology. If you turn the
first few pages in an introductionary geology textbook you will find
almost always information about hardness of minerals and rocks, which
are basic properties of rock.
We do not only want to understand how our planet works to make better
use of our reserves, but we also want to understand volcanic and
earthquake hazards to better protect ourselves against it.
Geology
Geology has a very wide range of subjects. Some geologists study the
processes that shape the earth's surface, others study rocks that cover
the first kilometers of the earth. There are also geologists that study
processes that take place deeper in the earth, for example underneath
mountains chains, volcanic islands, oceans and interiors of continents.
One might ask how geologists can study the rocks and processes at
depths that go beyond what we can drill. One answer is simply because
we can find rocks that have been at these depths at the
surface.
How do we know that rocks have been formed deep in the earth and not
always have been lying at the surface? This is what geologists have
been studying for years.
By carefully looking at what rocks are
composed of we can have a general idea about where they must have been
formed. Rocks are composed of components which are called minerals.
From
these minerals and the structure and textures in which the minerals
occur in the rock we can already tell a lot about their origin.
Experiments in laboratories have shown that minerals form at
specific pressures and temperatures and this tells us that rocks now
lying at the surface once have been deep in the earth. The fact that
these rocks at the surface still contain evidence of their early
evolution enables geologists to study or determine the
processes that were acting deep in the earth.
(to be continued)
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Strongly deformed metamorphic
rocks, at the coast north of Bud (Norway). Rocks that have been
deep in the earth, ready to study
at the surface.
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