9 Paleoceanography - the Deep-Sea Record
9.1 Background
Paleoceanography, the study of ocean history, emerged in the 1930s and 1940s, when
cores became available that provided data from which history could be reconstructed.
Initial efforts by W. Schott (1935) using short cores taken by the German research
vessel Meteor have been mentioned (Sect. 8.2.3). In essence, the Swedish Deep Sea
Expedition (1947-1948) played the same role in launching the new science of his torical oceanography that the Challenger Expedition had played 70 years earlier, for
physical and biological oceanography. The research vessel Albatross set out from
Gothenburg in 1947, to begin the circumnavigation of the world's tropical environment, under the leadership of Hans Petterson. The expedition used a new device, the
piston corer, developed by B. Kullenberg in Copenhagen. This technique typically
recovered cores of a length of 7 m or so, with the oldest sediment being from 0.3 to
1 million years in age. Kullenberg's device, with modifications, is still used today
(Fig. 9.1).
The scientists reporting on these cores became the founders of paleoceanograpy.
They defined the fundamental questions about the Pleistocene history of the ocean:
regarding changes in productivity (G. Arrhenius), in plankton distributions and surface currents (F. B. Phleger, F. L. Parker), in surface water temperature and ice
volume (c. Emiliani), and in deep circulation patterns (E. Olausson). Since then,
these questions, and related ones, have been pursued vigorously.
Beginning in 1968, when the drilling vessel GLOMAR Challenger (Fig. 0.6) left
port in Galveston (Texas) to initiate scientific drilling in the deep ocean, many new
dimensions have emerged in paleoceanography: the length of time available for detailed study increased from about 1 million years to the past 100 million years! Since
1985, the JOIDES Resolution (Fig. 0.7) has been employed for deep ocean drilling.
In unconsolidated ooze and mud nearly undistrubed sequences can be recovered by
this ship, using hydraulic piston coring. Recovery of several kilometers of core material, from a single 2-month leg, is not unusual. The study of these materials is
time-consuming and labor-intensive. It requires the coordination and cooperation of
marine geologists from many institutions, in the USA and abroad. The harvest of
these efforts has not yet been wholly reaped, and new findings are constantly being
reported.
The following summary illustrates some of the highlights of the various discoveries that resulted from coring and drilling. It it as much a survey of questions as
9.1 Background
Paleoceanography, the study of ocean history, emerged in the 1930s and 1940s, when
cores became available that provided data from which history could be reconstructed.
Initial efforts by W. Schott (1935) using short cores taken by the German research
vessel Meteor have been mentioned (Sect. 8.2.3). In essence, the Swedish Deep Sea
Expedition (1947-1948) played the same role in launching the new science of his torical oceanography that the Challenger Expedition had played 70 years earlier, for
physical and biological oceanography. The research vessel Albatross set out from
Gothenburg in 1947, to begin the circumnavigation of the world's tropical environment, under the leadership of Hans Petterson. The expedition used a new device, the
piston corer, developed by B. Kullenberg in Copenhagen. This technique typically
recovered cores of a length of 7 m or so, with the oldest sediment being from 0.3 to
1 million years in age. Kullenberg's device, with modifications, is still used today
(Fig. 9.1).
The scientists reporting on these cores became the founders of paleoceanograpy.
They defined the fundamental questions about the Pleistocene history of the ocean:
regarding changes in productivity (G. Arrhenius), in plankton distributions and surface currents (F. B. Phleger, F. L. Parker), in surface water temperature and ice
volume (c. Emiliani), and in deep circulation patterns (E. Olausson). Since then,
these questions, and related ones, have been pursued vigorously.
Beginning in 1968, when the drilling vessel GLOMAR Challenger (Fig. 0.6) left
port in Galveston (Texas) to initiate scientific drilling in the deep ocean, many new
dimensions have emerged in paleoceanography: the length of time available for detailed study increased from about 1 million years to the past 100 million years! Since
1985, the JOIDES Resolution (Fig. 0.7) has been employed for deep ocean drilling.
In unconsolidated ooze and mud nearly undistrubed sequences can be recovered by
this ship, using hydraulic piston coring. Recovery of several kilometers of core material, from a single 2-month leg, is not unusual. The study of these materials is
time-consuming and labor-intensive. It requires the coordination and cooperation of
marine geologists from many institutions, in the USA and abroad. The harvest of
these efforts has not yet been wholly reaped, and new findings are constantly being
reported.
The following summary illustrates some of the highlights of the various discoveries that resulted from coring and drilling. It it as much a survey of questions as