The Etive igneous complex has intruded into Dalradian and Moine meta-sedimentary rocks in Devonian. Main rock types of the complex are granodiorite, monzodiorite, monzogranite, granite and diorite. Geochemical studies show that the magmas were of high K calc-alkaline, I-type and metaluminous nature. Application of discriminant diagrams to the Etive rocks indicates a possible within-plate tecton...

Abstract The tectonic stress field of the southwestern Ordos Basin during Late Triassic is controversial. major controversy whether was a compressional basin throughout or it transformed from an extensional into this period. We divided early to middle and late terminal periods. Two paleotectonic simulation models were constructed using finite-element software (ANSYS 10). Our results showed high...

Previous studies have shown that the 2.04 Ga Kangâmiut dyke swarm of SW Greenland was injected into an active tectonic environment associated with the formation of the Nagssugtoqidian orogenic belt. Major and trace element modelling of the swarm shows that its chemical evolution was controlled by simple clinopyroxene–plagioclase fractionation. However, such trends — although typical of continen...

The petrology and geochemistry of serpentinized harzburgites within the Feather River Ophiolite in northern California were investigated to constrain the origin of serpentinization. Trace-element systematics indicate that serpentinization was associated almost solely with relatively low temperature hydrothermal addition of seawater and not with the addition of metamorphic fluids associated with...

Induced earthquakes currently pose a significant hazard in the central United States, but there is considerable uncertainty about the severity of their ground motions. We measure stress drops of 39 moderate-magnitude induced and tectonic earthquakes in the central United States and eastern North America. Induced earthquakes, more than half of which are shallower than 5 km, show a comparable med...

the etive igneous complex has intruded into dalradian and moine meta-sedimentary rocks in devonian. main rock types of the complex are granodiorite, monzodiorite, monzogranite, granite and diorite. geochemical studies show that the magmas were of high k calc-alkaline, i-type and metaluminous nature. application of discriminant diagrams to the etive rocks indicates a possible within-plate tecton...

[1] A simple dynamic model based on boundary layer theory shows that dynamic topography is unlikely to vary significantly in response to short term ( 20 Myr) variations in the mean tectonic velocity. Tectonic velocities essentially mirror variations in mantle viscosity, but are not indicative of substantial modification of dynamic topography, which primarily reflects mass anomalies in the mantl...

The main tectonic features in our study region are indicated in Fig. S1. We use 190 earthquakes for the iterative structure inversion (Fig. S2a). Most of the earthquakes are shallow (< 30 km), occurred from 1996 to 2011 (Fig. S3), and are evenly distributed along the North Atlantic Ridge and the Mediterranean-Himalayan belt. Initial source parameters (e.g., centroid time, location, etc.) are co...

Surface-wave methods are widely used in earth sciences and engineering for the geometric characterization of geological bodies and tectonic structures of the subsurface. These techniques exploit the dispersive nature of Rayleigh waves to indirectly estimate shear wave velocity profiles from surface-wave measurements; however, they are limited to parallel-layered geometries. To overcome such lim...