Traffic Patterns in the Silk Road Economic Belt and Construction Modes for a Traffic Economic Belt across Continental Plates

Plans for the Silk Road Economic Belt （SREB） include construction of two axes, two belts and two radiated areas. As a significant national strategy for China, the emphasis is on the construction of roads and achieving economic agglomeration and radiation through the construction of traffic axes. Using published literature and data analyses, this paper studied current traffic patterns between China and other regions within the SREB from the perspective of rail, ocean and air transportation. With regard to existing problems and development prospects of these three types of transportation, we propose construction modes for the traffic economic belt across continental plates and that future construction within the SREB should consider key cities as joints and arterial traffic lines as development axes, promote connecting of joints by lines, advance deep construction through joints and axes, connect lines into net, and develop informationalized traffic economic belt on the basis of trans-regional cooperation.

The effects of the thermal state of overriding continental plate on subduction dynamics: Two-dimensional thermal-mechanical modeling

The dynamic process of ocean-continent subduction depends on not only the properties of the subducting oceanic plate,but also the characteristics and state of the overriding continental plate.Numerical models conducted to date have mostly focused on the oceanic lithosphere in this regard;research on the properties of overriding continental lithosphere remains relatively limited,especially the influence of its thermal state on subduction dynamics.Here we explored the performance of continental lithosphere with different thermal states during the subduction process using two-dimensional thermal-mechanical modeling and systematically investigated the effects of the thermal state of overriding continental plate,the age of subducting oceanic plate,and relative convergence rate on subduction dynamics.Modeling results show that:(1)When the geothermal gradient of continental crust is low(between 10 and 15℃km^-1),the oceanic plate first subducts at a low angle.As subduction continues,the slab dip gradually increases and the slab begins to retreat rapidly driven by its negative buoyancy,opening an ocean basin ranging from 600 to 1100 km in width.This leads to the decoupling between the overriding continental plate and oceanic plate.As the trench retreat continues,the horizontal deviatoric stress inside the overriding continental crust alternates between being positive and negative in a local area.Thinning of the overriding lithosphere mainly occurs at the region adjacent to the subduction zone,where the surface experiences significant subsidence.(2)When the geothermal gradient of continental crust is higher(greater than 15℃km-1),oceanic plate retreat causes the overriding continental plate to be strongly stretched.In this case,the trench retreat distance decreases and the width of the ocean basin also reduces by between 100 and 1000 km.The horizontal deviatoric stress inside the whole overriding continental crust first manifests as compression and then changes into extension,which causes the surface to first uplift and then slowly subside.(3)Increasing the age of oceanic lithosphere accelerates trench retreat and promotes overriding plate thinning.(4)An advancing overriding continental plate slows down trench retreat.In cases where the geothermal gradient of continental crust is greater than 17.5℃km-1,the hot continental crust experiences gravitational collapse and is overthrusted onto oceanic lithosphere,resulting in slow trench retreat.We analyzed the subduction process of the western Paleo-Pacific Plate in the Early Cretaceous based on our modeling results and discussed its possible control on the tectonic evolution of the rift basins in east Asia.We suggest that the development of a wide rift basin system on the Amurian Superterrane in the Early Cretaceous was likely related to slow trench retreat and the collapse of the hot crust,and the formation of a series of passive rift basins in the North China Craton was likely caused by the relatively cold thermal state of the lithosphere and the rapid retreat of the Paleo-Pacific Plate.

Tectonic Related Lithium Deposits Another Major Region Found North East Tanzania—A New Area with Close Association to the Dominant Areas: The Fourth of Four

The current “mega” interest in Lithium resources was spurred by the development of Lithium-Ion batteries to aid in restructuring the world’s reliance on carbon spewing power petroleum reserves. Current resources of lithium recovery have fallen into two main categories—Pegmatite, found worldwide associated with felsic intrusions and Brine Related, and now with development in the Southwest United States of America (SWUS), a third category— Tertiary Volcanic clays, are specifically associated with Tertiary volcanics and major Tectonic Plate interactions. “Active” Plate tectonics is important as both the SWUS, the Lithium Triangle of South America (LTSA) and the Tibetan Plateau of China (TPC) producing tertiary (Miocene) volcanism that is important to the development of Lithium resources. The Tanzanian part of the East Africa Rift System (EARS) has features of both the SWUS, tertiary volcanic related “playas” and Continental rifting, the LTSA, tertiary volcanic related “Brines” and a major Tectonic plate event (subduction of an Oceanic Plate beneath the Continental South American Plate) and the TPC, tertiary volcanics (?) and major tectonic plate event (subduction of the Indian Continental Plate under the Eurasian Continental Plate). As well as the association of peralkaline and metaluminous felsic volcanics with Lithium playas of the SWUS and the EARS (Tanzania) “playas”. These similarities led to an analysis of a volcanic rock in Northeast Tanzania. When it returned 1.76% Lithium, a one-kilometer spaced soil sampling program returned, in consecutive samples over 0.20% Lithium (several samples over 1.0% lithium and a high of 2.24% lithium). It is proposed that these four regions with very similar past and present geologic characteristics, occur nowhere else in the world. That three of them have produced Lithium operations and two of them have identified resources of Lithium clay and “highly” anomalous Lithium clays should be regarded as more than “coincidental”.

Early Cenozoic rapid flight enigma of the Indian subcontinent resolved:Roles of topographic top loading and subcrustal erosion

Intrinsic magmatic processes are considered as critical operators of plate movements. Here we demonstrate the role of extrinsic processes consequent to intrinsic processes as a catalyst for anomalous rapid plate movement. The rapid and accelerated flight of the Indian subcontinent since Deccan volca- nism until its collision with Eurasia remains as one of the geological conundrums. Data on seismic to- mography, peninsular geomorphology and inferences on continuum of subcrustal structures are utilized to address this enigma. We propose geomorphic isostasy as the mechanism that has driven this fastest drift ever recorded in geological history. It was initiated by sudden instability after the Deccan volcanism and resultant extensive accumulation of lava pile over continental lithosphere of northern India, northern-eastern tilt due to crustal thickness heterogeneity and subcrustal thermal stratification. The drift was sustained by Carlsberg and Central Indian ridge-push until collision and sediment top loading at northeast thenceforth. These inferences and geomorphic isostasy as a catalytic mechanism necessitate variability of drift rates as integral inputs for any continental scale modeling.