-
Date submitted2018-06-27
-
Date accepted2018-09-18
-
Date published2018-12-21
Migration forms of chemical elements in the intrusive rocks of the Eastern Desert (El Sela area, Egypt)
- Authors:
- M. M. Ghoneim
- E. G. Panova
In the Egypt's Eastern Desert intrusive rocks with U-REE mineralization (two-mica granites, microgranites, dolerites, and bostonites) are developed. We estimated the content of chemical elements in reference samples of intrusive rocks and also in their water-soluble (colloid-salt) fraction. This fraction is water-extracted from the rock under certain conditions. The rock sample and its colloid-salt fraction are analyzed using ICP-MS. The chemical characteristic of the extracted fraction reflects the mobile migrating part of the chemical elements in the composition of the rocks. Comparison of the obtained data allows us to estimate the share of migrating and weakly migrating elements.
-
Date submitted2015-07-21
-
Date accepted2015-09-24
-
Date published2016-02-24
Tectonic development and granitoid magmatism of Northeast Asia in the late mesozoic
- Authors:
- V. I. Alekseev
The history of tectonic development and granitoid magmatism of Northeast Asia in the late Mesozoic is considered. The variety of tectonic situations and granitoid magmatism are favorable circumstances for the solution of many fundamental problems in geology, but tectono-magmatic division into districts is complicated owing to variability of the composition and the structure of the Earth’s crust. A rational approach to the tectonic division into districts of a region by the research of granitoid magmatism based on determining consolidated crust blocks with various tectonic history is offered. Pre-mesozoic and mesozoic structures of the Far East, among which primary and superimposed on the Precambrian and Paleozoic base Verkhoyansk orogeny prevails, are determined. The conclusion on the important role of middle massifs and passive margins with a thin Riphean-Paleozoic cover in geodynamic development of the Far East is drawn. The mesozoic activization of ancient structures along with young granitoid magmatism is established. The driving force of the Pacific ore belt granitization was the interaction of the Paleo-Pacific Plate and plates in Northeast Asia in the middle-late Mesozoic. The history of regional tectogenesis and granitoid magmatism in the late Triassic–Eocene (230-33,7 million years) taking into account the latest geodynamic concepts is tracked. The place in tectonic history of the Asian continental margin of plutonic and volcanic-plutonic belts is determined. Four stages of tectonomagmatic development of the Far East are established: the Jurassic and the early Cretaceous collisional, the early Cretaceous upsubduction, the late Cretaceous upsubduction-transform and the late Cretaceous–Paleogene rift-related.
-
Date submitted2008-10-10
-
Date accepted2008-12-23
-
Date published2009-12-11
Modern methods of hydrogeological investigations in terms of prospecting of titanium-magnetic iron deposit «South-East Gremiakha»
The paper considers the contemporary level of hydrogeological investigations during prospecting of deposits. It is suggested to use numerical modeling, sensors, computer programs for pumping tests. These methods are illustrated by prospecting of the South-East Gremiakha deposit.