CHEMICAL OCEANOGRAPHY

SID

• Chemical oceanography is the study of ocean chemistry: the behavior of the chemical elements within the Earth's oceans. The ocean is unique in that it contains - in greater or lesser quantities - nearly every element in the periodic table.

• Much of chemical oceanography describes the cycling of these elements both within the ocean and with the other spheres of the Earth system

• Another important area of study in chemical oceanography is the behaviour of isotopes and how they can be used as tracers of past and present oceanographic and climatic processes.

• Also Oceans are a potential source .Extraction of these elements from the oceans is a challenge to the chemical engineers

THE OCEANIC PROPERTIES

COMPONENTS OF SEAWATER

VARIATION OF PROPERTIES

• Because of the intricate buffering relationships in the oceans combined with mixing and currents over long geological time periods, the major constituents (ions) of seawater have very constant ratios to one another, and are therefore, also termed conservative constituents.

PRINCIPLE OF CONSTANT PROPORTIONS

DENSITY OF SEAWATER

DISSOLVED GASES

PH OF SEAWATER

ACID BASE BALANCE

MANIFESTATIONS OF THE SEAWATERNVK

SEA ICE

ICEBERG

BIOGEOCHEMICAL CYCLE

• In Earth science, a biogeochemical cycle or substance turnover or cycling of substances is a pathway by which a chemical substance moves through both biotic (biosphere) and abiotic (lithosphere, atmosphere, and hydrosphere) compartments of Earth. A cycle is a series of change which comes back to the starting point and which can be repeated

• The term "biogeochemical" tells us that biological, geological and chemical factors are all involved. The circulation of chemical nutrients like carbon, oxygen, nitrogen, phosphorus, calcium, and water etc. through the biological and physical world are known as biogeochemical cycles. In effect, the element is recycled, although in some cycles there may be places (called reservoirs) where the element is accumulated or held for a long period of time (such as an ocean or lake for water)

SOME COMMON CYCLE

•The carbon cycle, •the nitrogen cycle, •the oxygen cycle, •the phosphorus cycle, •the sulphur cycle, •the water cycle, •and the rock cycle.

ISOTOPE GEOCHEMISTRY

• Isotope geochemistry is an aspect of geology based upon study of the natural variations in the relative abundances of isotopes of various elements. Variations in isotopic abundance are measured by isotope ratio mass spectrometry, and can reveal information about the ages and origins of rock, air or water bodies, or processes of mixing between them.

• Stable isotope geochemistry is largely concerned with isotopic variations arising from mass-dependent isotope fractionation, whereas radiogenic isotope geochemistry is concerned with the products of natural radioactivity.