As the full horror of the Asian tsunami sinks in, the reactions
of scientists echo those of the population as a whole. These
range from a sense of hopelessness in the face of nature’s
power to concern for the victims and a determination that their
suffering should be addressed.
Earth as an Evolving Planetary System presents the key topics and questions relating to the evolution of the Earth's crust and mantle over the last four billion years. It examines the role of plate tectonics in the geological past via geological evidence and proposed plate reconstruction.
Kent Condie synthesizes data from the fields of oceanography, geophysics, planetology, and geochemistry to examine the key topics and questions relating to the evolution of the Earth's crust and mantle.
Asthenosphere A region of the earth’s upper mantle at a
depth of approximately 75–150 km, characterized by
low mechanical strength, attenuation of seismic shear
waves, and partial melting. The term was coined in
the 1910s by geologist Joseph Barrell to describe the
zone in which isostatic adjustment occurs and basaltic
magmas are generated. With the development of plate
tectonics in the 1960s, the asthenosphere is now un-
derstood as the plastic zone over which the rigid plates
Many have endeavored to make our outdoor environment cleaner and safer. The learning
process that occurred showed us the limitations of our planet and also the sustainability
of our ecosystem if given a chance. As a community, we learned about the water, the soil,
and the air. We learned about the underground river that flowed to the surface lake. We
learned about air currents that transported airstreams around our globe. We discovered the
reality of plate tectonics and the ever-changing hydrogeological system.
In a classic paper by the late Yale historian of
science, Derek De Solla Price (1965), based
mainly on the study of citations in a single scientific
research field, it was shown how citations in
a developing research area have a strong
'immediacy effect'.1 Citation was found to be at
a maximum for papers about two-and-a-half
years old, and the 'major work of a paper ... [is]
finished after 10 years', as judged by citations.
Earth Science is made up of many diﬀerent areas of geological study. Since
the Earth contains everything from clouds (meteorology) and oceans (marine
biology) to fossils (paleontology) and earthquakes (geology/plate tectonics),
there is a lot to choose from!
Alfred Wegener -1912 large “supercontinent” (Pangea) existed and then split into pieces fossil & glacial deposit evidence
Wegener not able to provide MECHANISM for his theory Major mechanism later found in the OCEANS Harry Hess - 1960s new ocean basins form from volcanism ocean floor forms IN BETWEEN pieces that have split SEAFLOOR SPREADING
The first version of this text was written to serve as lecture notes for a first term geology course in “Minerals and Rocks” at Aarhus Universityin Denmarkin 2003. In Aarhus this course is accompanied by a general “Introduction to Geology” course that presents, for example, the structure of the Earth, plate tectonics and paleontology. These topics are therefore not treated here, and some knowledge of the Earth´s structure and plate tectonicsis assumed.
Earth’s ecosystems, earth’s land and water, heat energy, energy in the earth system, plate tectonics and earth’s structure, shaping earth’s surface, earth’s resources,... is the main content of the book "Reading and writing in science". Invite you to consult the text book for more documents serving the academic needs and research.