Transitional Zone

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Transitional Zone


a major global morphostructure located between the underwater continental margin and the ocean floor. Typical transitional zones are encountered along the northern and western margins of the Pacific Ocean, in parts of the Caribbean and Scotia seas, and in the northeastern part of the Indian Ocean. They consist of the basins of marginal seas, island arcs, and deep trenches. Such zones are characterized by the most varied types of relief, ranging from trenches with depths of 11 km to volcanic peaks with elevations to 5–7 km on the island arcs.

Transitional zones are marked by sharp differences between the values of the magnetic and gravitational fields and heat flow values (greater values on the island arcs and values below the norm in the trenches) and by rapid and sharp differentiation in vertical movement of the earth’s crust. Under the basins of the deep-water seas the crust is suboceanic, whereas under the island arcs it is subcontinental and sometimes continental. In the oceanic trenches, the crust may be subcontinental, suboceanic, or oceanic. The transitional zone is an area of volcanic activity, intense seismic activity, and mountain formation.


References in periodicals archive ?
3] performed multivariate analyses using a large multicentre cohort of patients treated with TURP, and concluded that high PSA and low transitional zone volume could be used as predictive factors of incidental prostate cancer.
Study communities in the Forest-Savannah Transitional zone served as an important food hub for the country; hence there was a wide range of ASF in the markets including many varieties of bush meats [4].
In Figure 5 the oxide and transitional zones are shown as green from 0 to 38 metres downhole.
When intruding into the main metal (cast iron) in the transitional zone (the heat affect zone) the crack meets inside defects: pores, nonmetallic insertions (Fig.
The proposed advantages/ disadvantages of transitional zone and seminal vesicle biopsies were also summarized.
On the figure changes in the transitional zone are visible.
Lying south of the Sahara, the Sahel is a vast, semi-arid region that forms a transitional zone between the desert and dry tropical climates.
In the course of numerous investigations of quality of the transitional zone metal and branch pipes, melted on bodies of NPP equipment from 22K steel, it was registered that on this steel as well full restoration of the metal properties in the overheating zone is achieved after normalization with tempering.
In 2001, YF cases were detected in the transitional zone of Minas Gerais and further east.
For this reason, the term "treeline" represents a transitional zone rather than an exact altitudinal line (Holtmeier, 1985).
The clayey plasma of the primary peds, defined as microporosity, and the interpedal pore space defined as macroporosity, are in contact through a transitional zone that is assimilated to the surface of the primary peds.