РАСПРЕДЕЛЕНИЕ ОСАДОЧНОГО ЧЕХЛА В ЭКВАТОРИАЛЬНОМ СЕГМЕНТЕ АТЛАНТИКИ

Abstract

The thickness of the Atlantic Equatorial segment sedimentary cover decreases with the distance from the continental source of mass removal and increases slightly with the distance from the Mid-Atlantic Ridge (MAR). Background sedimentation makes a small contribution to the total sedimentary volume near the continents and the major contribution in basins with the formation of sedimentary bodies with a thickness of no more than 500 m. Sedimentary bodies with a thickness up to 1000 m near MAR are the results of unloading of bottom currents near structural barriers in topography and in fault troughs. The total thickness tends to increase from north to south on the western flank of the MAR. The multidirectional spatial migration of the basement depressions filled with sediments is revealed. To the west of the MAR, contrasting acoustic stratification and tectonic deformations of sediments were found. To the east of the MAR, deformations are rare and expressed by piercing structures and normal faults. Anomalies of the "bright spot" type associated with local manifestations of magmatism forming aligned high-amplitude reflectors are revealed. Normal faulting in the passive parts of the transforms zones indicates the presence of local stretching, which is part of the simple shear paragenesis. In the troughs, sediment deposition from the bottom currents, which forms channel drifts, is revealed.