Identification Features of the Transition and Intermediate Layers in the Polygonal Peatlands in Northwestern Siberia

Doklady Earth Sciences - The upper part of the subsurface component of the Earth’s cryosphere—polygonal peatlands—are considered in this paper. The polygonal peatlands are...     

Exploration of magnetic anomalies of the Baikal rift zone

The paper presents the results of an experimental study of natural magnetic field anomalies in the Baikal rift zone.     

Seasonal Thawing Local Changes Indicators for UAV-Based Cryolithozone Mapping

Doklady Earth Sciences - Remote sensing methods make it possible to evaluate the reaction of the cryolithozone and tundra landscapes in hard-to-reach Arctic areas based on the indicators of modern...     

Geomagnetically induced currents in power lines according to data on geomagnetic variations

The time derivative (d H/dt) of the geomagnetic field horizontal component (H) for seven intervals of high geomagnetic activity in 2003–2005 has been calculated, based on the data of Alma-Ata, Novosibirsk, and Irkutsk observatories, in order to estimate the probability of appearance of geomagnetically induced current (GIC), the value of which is linearly dependent on d H/dt, in power lines on the territory of Kazakhstan. The distributions of the H and d H/dt directions have been constructed; in this case it was most interesting that these distributions were narrow and extended along the magnetic meridian for Alma-Ata and were wider angular for Novosibirsk and Irkutsk. It has been indicated that large H values, determining significant GIC values, took place at a sudden commencement of strong storms, which had a character of a pulsed disturbance of the geomagnetic field, and during large-amplitude geomagnetic field pulsations. The duration of the periods of large |d H/dt| values exceeding the threshold (30 nT/min), when GIC could cause unwanted consequences in power circuits, has been determined.