Page 12 - Drilling Technology in Nontechnical Language

Chapter 1 – DRILLING GEOLOGY 3

Earth, with Proofs and Illustrations. Starting at the bottom of the diagram
(the square marked as “Magma” or molten rock), move clockwise and
upwards around the cycle. Magma cools and solidifies, creating igneous

rock. These rocks may be changed into metamorphic rock (branch going
to the right) or, continuing around the cycle, may eventually reach the
surface and are eroded.

Fig. 1–2. The rock cycle

The rock particles released by erosion (weathering) are transported
by wind, ice, or water. These are deposited to form sediments, which
become converted to sedimentary rock (now at the right-hand side of the
cycle). From here, the sedimentary rock could be eroded again, or buried

deeper. If buried at sufficient depth, the pressure and temperature will
metamorphose the sedimentary rock.
Metamorphic rock can be uplifted and eroded, or buried deeper and
melted.

Apart from these “physical” sediments, chemical sediments also
occur. Salt beds formed from the drying of salty lakes can be very thick

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