1
زمینشناسی و معدن::
پوسته اقیانوسی
Basaltic extru- sions at intra-ocean hot spots can thicken the basalt /gabbro oceanic crust to thicknesses up to
This confirms that low degrees of partial melting prevailed in the equato- rial Atlantic (therefore, the oceanic crust at the Vema Transform Fault is of low thickness; Fig. 5.12) whereas around the Azores, a high degree of partial melting is assumed.
Shown are rates of formation of ocean crust (at hot spots and mid-ocean ridges), high-latitude temperatures, and sea level eleva- tion, each compared to the present.
As a consequence of the strong magmatic activity within the plates, as well as at the mid-ocean ridges, new oceanic crust, highly elevated oceanic plateaus, oceanic islands, and seamounts were rapidly formed.
Approximately 125 Ma, the total production of oceanic crust increased, within a time interval of only a few million years, from around 20 km3 per year (this corresponds more or less to the present value) to about 35 km3 per year (Fig. 6.20).
واژگان شبکه مترجمین ایران