Search results
Results from the WOW.Com Content Network
Volcanic passive margins represent one endmember transitional crust type, the other endmember (amagmatic) type is the rifted passive margin. Volcanic passive margins also are marked by numerous dykes and igneous intrusions within the subsided continental crust. There are typically a lot of dykes formed perpendicular to the seaward-dipping lava ...
Norwegian Margin; US Atlantic Margin; Map showing the distribution of Earth's passive margins with known volcanic and non-volcanic margins distinguished. The margins are marked with color masks where the darkest blues and reds are non-volcanic and volcanic passive margins, respectively.
Movements of tectonic plates create volcanoes along the plate boundaries, which erupt and form mountains. A volcanic arc system is a series of volcanoes that form near a subduction zone where the crust of a sinking oceanic plate melts and drags water down with the subducting crust. [9] The Dome of Vitosha mountain next to Sofia
Tectonic subsidence is the sinking of the Earth's crust on a large scale, relative to crustal-scale features or the geoid. [1] The movement of crustal plates and accommodation spaces produced by faulting [2] brought about subsidence on a large scale in a variety of environments, including passive margins, aulacogens, fore-arc basins, foreland basins, intercontinental basins and pull-apart basins.
As the edge of North America moved away from the hot rift zone, it began to cool and subside beneath the new Atlantic Ocean. This once-active divergent plate boundary became the passive, trailing edge of westward moving North America. In plate tectonic terms, the Atlantic Plain is known as a classic example of a passive continental margin. [20]
Salt surface structures are extensions of salt tectonics that form at the Earth's surface when either diapirs or salt sheets pierce through the overlying strata. They can occur in any location where there are salt deposits, namely in cratonic basins, synrift basins, passive margins and collisional margins.
Typical passive margin cross-section. Passive margins are long-lived and generally become inactive only as a result of the closing of a major ocean through continental collision resulting from plate tectonics. As a result the sedimentary record of inactive passive margins often are found as thick sedimentary sequences in mountain belts. For ...
As the passive margin matures, the crust and uppermost mantle become colder and stronger, so that the compensating deflection in the base of the lithosphere is broader than the actual rift. Higher flexural strength results in a broadening of the gravity anomaly with time.