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Answers to Problems
Chapter 1
Answer 1
Deep-sea or red clay covers the deep ocean
basins below CCD. Calcareous sediments cover
topographic highs like ocean ridges above CCD.
Siliceous sediments occur in the Southern Ocean
around Antarctica, along the equator in the
Indian and Pacific oceans. Terrigenous sediments
drape the continental margins.
Answer 2
Because of chemical tropical weathering, Kaolinite
is considered the “clay mineral of low latitudes”.
As a product of continental weathering Illite
shows high concentration at mid-latitudes of the
northern oceans surrounded by great land masses. Chlorite as a product of physical weathering
is essentially inversely related to kaolinite and
referred to as the “high latitude mineral”. Smectite
showing a very variable distribution in the oceans
is generally considered as an indicator of a “volcanic regime”.
Answer 3
Large quantities of sediment are provided by
rivers and directly from land and deposited on the
shelf and/or directly beyond the shelf edge on
the continental slope. The youngest crust occurs
along the mid-Atlantic ridge and increases with
distance from the ridge to the margin where more
time is available to accumulate greater sediment
thicknesses.
Answer 4
Basically, sedimentation rate decreases with
increasing distance from the sediment source.
Since for terrigenous sediments fluvial input is the
major source sedimentation rate decreases with
distance from river mouth and/or coast. The
lowest values are reached in the oceanic basins
far offshore where red clay accumulates extremely
slowly. Sedimentation rate for biogenic sediments
– calcareous as well siliceous – depends on high
biogenic production, on carbonate compensation
depth CCD) and dilution by terrigenous sediments
is low.
Answer 5
Deep sea sediments are generally best described
by composition according to particle origin, e.g.
non-biogenic (terrigenic, volcanic) versus biogenic and can further be differentiated according to
mineralogy (carbonate or opal) and/or texture
(mud, ooze, clay).
With respect to relative distance from shore or
continents sediments are called “pelagic sediments” consisting of biogenic oozes (carbonate
and/or siliceous) and only very little admixtures of
extremely fine-grained land derived material. They
are distinguished from “hemipelagic sediments”
typically deposited along continental margins and
containing a substantial portion of land or shallow
water derived components.
Chapter 2
Answer 1
Bulk parameters are based on a volume-oriented
model which only depends on the total amount of
pore fluid and sediment grains. Acoustic/elastic
parameters like P- and S-wave velocity and attenuation are based on a micro-structure oriented
model which considers both the amount and
distribution of pore fluid and sediment grains.
Answer 2
A direct method is the analysis by weight and
volume, indirect methods are gamma ray attenuation and electrical resistivity measurements.
Answers to Problems
Chapter 1
Answer 1
Deep-sea or red clay covers the deep ocean
basins below CCD. Calcareous sediments cover
topographic highs like ocean ridges above CCD.
Siliceous sediments occur in the Southern Ocean
around Antarctica, along the equator in the
Indian and Pacific oceans. Terrigenous sediments
drape the continental margins.
Answer 2
Because of chemical tropical weathering, Kaolinite
is considered the “clay mineral of low latitudes”.
As a product of continental weathering Illite
shows high concentration at mid-latitudes of the
northern oceans surrounded by great land masses. Chlorite as a product of physical weathering
is essentially inversely related to kaolinite and
referred to as the “high latitude mineral”. Smectite
showing a very variable distribution in the oceans
is generally considered as an indicator of a “volcanic regime”.
Answer 3
Large quantities of sediment are provided by
rivers and directly from land and deposited on the
shelf and/or directly beyond the shelf edge on
the continental slope. The youngest crust occurs
along the mid-Atlantic ridge and increases with
distance from the ridge to the margin where more
time is available to accumulate greater sediment
thicknesses.
Answer 4
Basically, sedimentation rate decreases with
increasing distance from the sediment source.
Since for terrigenous sediments fluvial input is the
major source sedimentation rate decreases with
distance from river mouth and/or coast. The
lowest values are reached in the oceanic basins
far offshore where red clay accumulates extremely
slowly. Sedimentation rate for biogenic sediments
– calcareous as well siliceous – depends on high
biogenic production, on carbonate compensation
depth CCD) and dilution by terrigenous sediments
is low.
Answer 5
Deep sea sediments are generally best described
by composition according to particle origin, e.g.
non-biogenic (terrigenic, volcanic) versus biogenic and can further be differentiated according to
mineralogy (carbonate or opal) and/or texture
(mud, ooze, clay).
With respect to relative distance from shore or
continents sediments are called “pelagic sediments” consisting of biogenic oozes (carbonate
and/or siliceous) and only very little admixtures of
extremely fine-grained land derived material. They
are distinguished from “hemipelagic sediments”
typically deposited along continental margins and
containing a substantial portion of land or shallow
water derived components.
Chapter 2
Answer 1
Bulk parameters are based on a volume-oriented
model which only depends on the total amount of
pore fluid and sediment grains. Acoustic/elastic
parameters like P- and S-wave velocity and attenuation are based on a micro-structure oriented
model which considers both the amount and
distribution of pore fluid and sediment grains.
Answer 2
A direct method is the analysis by weight and
volume, indirect methods are gamma ray attenuation and electrical resistivity measurements.