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Late Paleozoic sedimentary strata outcrop extensively in central Inner Mongolia, and are a key to understanding the tectonic evolution of the southeastern Central Orogenic Belt. A combined analysis of petrography, whole-rock major and trace element, and Nd isotope is carried out on representative sandstones from the Late Paleozoic sedimentary strata (420–270 Ma). The sandstones are mainly wackes and litharenites in lithology, with low SiO2/Al2O3 of 2.85–9.47 (averagely 5.22) and poor textural and compositional maturities, implying short sediment transportation between the depositional basins and provenances. The trace element compositions are generally comparable to that of the average upper continent crust (UCC), with negatively-sloping chondrite-normalized rare earth element distribution patterns ((La/Yb)N = 3.43–11; averagely 6.94) and flat UCC-normalized trace element distribution patterns. The Nd isotopic compositions show great variation (ԐNd(t) = −5.01 to 5.35) with depositional time of the sandstones, and coincide well with the arc magmatic phases in central Inner Mongolia. The geochemical signatures of the sandstones indicate that the dominant provenances are intermediate to felsic arc magmatic rocks that have ages approximating the deposition, although old, recycled sediments may have made a minor contribution. An active continental arc setting during the Late Paleozoic in central Inner Mongolia, controlled by the northward subduction of the Paleo-Asian oceanic slab, was the most likely depositional tectonic setting of the sandstones. This active continental arc setting continued to at least 270 Ma, implying that the final closure of the Paleo-Asian Ocean along the Solonker suture zone most likely occurred sometime during the Late Permian to Early Triassic. The northward subduction of the Paleo-Asian Ocean is likely of West Pacific-style, in which the present-day Baolidao arc has a close genetic link with the South Mongolian microcontinent and, likely, the former originally formed as the arc margin of the latter.

The tectonic evolution of the Hegenshan Ocean is an important but poorly understood issue in the geology of the southeastern Central Asian Orogenic Belt (CAOB). Here we present an integrated study ...

The Erlian Basin is an important part of the late Mesozoic extensional basin system in Northeast Asia. The basin contains thick Jurassic–Lower Cretaceous rocks and provides excellent opportunities to understand intracontinental deformation in Northeast Asia during the late Mesozoic. However, the Jurassic–Early Cretaceous evolution of the basin and associated driving mechanisms remain disputed. Based on 13 new zircon U-Pb ages for the Jurassic–lowest Cretaceous strata in the Erlian Basin, the correlation of Jurassic–lowest Cretaceous strata between the Erlian Basin and the Yan Shan is reestablished and a high-precision chronostratigraphic framework is presented. The Aqitu–Qiha formations are ascribed to the Aalenian–early Bathonian (ca. 174–167 Ma), the Xing'anling Group to the Oxfordian–early Kimmeridgian (ca. 163–153 Ma), the Hugejiletu Formation to the Tithonian–early Valanginian (ca. 151–139 Ma), and the Aershan Formation to the Valanginian–? (≤ca. 138 Ma). Combined with seismic reflection profiles, the Jurassic–earliest Cretaceous tectonostratigraphic evolution of the Erlian Basin is reconstructed and five major phases of deformation are revealed. These deformation phases include Aalenian–early Bathonian initial extension, late Bathonian–Callovian compression, Oxfordian–early Kimmeridgian extension, late Kimmeridgian–earliest Valanginian compression, and Valanginian extension. Integrated with geological evidences from peripheral regions of the Erlian Basin, potential driving mechanisms related to far-field tectonic events along Asian margins are suggested for each of these deformation phases.

A 2-D shooting-and-bouncing (SBR) ray-tracing method considering ray reflect, transmission and diffraction is used to analyze antenna spacing effect on capacity complementary cumulative distribution functions(CCDFS) of indoor non-line-of-sight (NLOS) MIMO channel and indoor multiple-input multiple-output (MIMO) channel with line-of-sight (LOS) path. The results show that the capacities of MIMO channel with LOS path are less than NLOS MIMO channel capacities in general. But whether in indoor MIMO channel with LOS path or in NLOS indoor MIMO channel, capacities CCDFS of indoor MIMO systems with antenna spacing of 5/spl times/ can reach the theoretical independent and identically distribution (i.i.d) Rayleigh capacities nearly fully. With the decrease of antenna spacing, the capacities dropped also. And the less antenna spacing, the more difference between indoor NLOS MIMO channel capacities and capacities of MIMO channel with LOS path.