Magnetic anomalies and the features of geodynamic development of the Antarctic Peninsula continental margin structures
Journal Title: Геофизический журнал - Year 2017, Vol 39, Issue 3
Abstract
New geophysical models of the Earth's crust were used to study the possible nature of the Pacific Margin Anomaly (PMA) near the Antarctic Peninsula (AP). The data have been presented, which permitted analyzing spatial distribution of PMA and its deep sources on the continental margin of AP. Western and Eastern PMA-branches may correspond to different crustal blocks associated with predominantly Cretaceous magmatic intrusions of basic rocks. These branches of PMA were formed in the Early Cretaceous in structures, separated by a fault zone. Spatial heterogeneity of different segments of РМА may also be connected with different depth, thickness and magnetic susceptibility of separate bodies, which form the sources of regional anomalies. Active tectonic processes in the Mesozoic—Cenozoic resulted in the complex evolution of the structures of the region and appearance of vast deep magnetic sources of PMA along the AP margin formed during the phases of magmatic activity. Formation of separate segments of PMA can be connected with processes of tectonic movements near the border of the plates (Antarctica and Scotia) as well as in the areas of paleorifts formation. New geophysical results for different PMA-segments (from the Palmer Land to Powell Basin) replenish current ideas on the sources and origin of this big positive magnetic anomaly of the Pacific coast and show the necessity of searching new mechanisms of forming the structures of continental margin of AP.
Authors and Affiliations
V. D. Soloviev, I. N. Korchagin
East-European microplate as an indentor and its orogenic margin
A problem of modern orogenesis in the northern margin of the East-Black Sea micro-plate has been considered based on numerical modeling. It has been shown that only the upper part (up to 40 km) of its sub-oceanic lithosp...
Designed accelerograms for the direct dynamic method of determining seismic loads
To calculate the seismic stability of objects by the direct dynamic method of seismic loads, computed accelerograms for specified constructing site are required. The article shows that the use of accelerograms, which do...
Occurrence of metal iron inside the planets
Comparison of thermomagnetic and microprobe data on metal iron in terrestrial rocks (xeno- lithes, Siberian trap and oceanic basalt) has been conducted with the data on extraterrestrial metal iron (in sediments, lunar ba...
The structure of the Earth’s crust of the central part of the Holovanivsk suture zone according to the reinterpretation of materials of IV geotraverse of DSS (PK 295—400)
The paper presents the results of reinterpretation of the materials obtained as a result of studies using the DSS method along the IV geotraverse at the site PK 295—400. The reinterpretation was carried out purposefully...
Problems of Precambrian paleomagnetism on the territory of Ukraine
Some problems of paleomagnetic research of the Precambrian rocks of Ukraine are considered. The results of paleomagnetic researches of the Proterozoic rocks of the Ukrainian Shield, Ediacaran traps of Volyn and sedimenta...