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Cretaceous Late Yanshanian (LY) magmatism produced large amounts of I-type granitoids in the Southeast Coast Magmatic Belt (SCMB). I-type granitoids from Xiaojiang-Liangnong complexes (N Zhejiang) in the northern part of this belt are characterized by containing abundant mafic microgranular enclaves (MMEs). On the basis of petrography and mineralogy, two types of MMEs are recognized. One (Type 1), enclosed in the granodiorite, is composed of amphibole, high-Ti tabular biotite, plagioclase, K-feldspar, and quartz. Using the Al-in-amphibole geobarometer, a shallow origin (4 - 8 km) of amphiboles is suggested. The other (Type 2), enclosed in alkali feldspar granite, is amphibole-free and composed of low-Ti acicular biotite, plagioclase, K-feldspar, and quartz. Geochemistry of major and trace elements seems to reflect two different evolving trends for these host granitoids. The Sr-Nd isotopic features indicate that all the studied samples vary in a narrow range of Isr (0.7078 to 0.7082) and εNd(T) (-5.6 to -8.3), except the Type 2 enclaves and hosts that show slightly more depleted compositions (Isr = 0.7073 to 0.7075 and εNd(T) = -5.0 to -6.0). U-Pb zircon ages obtained are 109.6 ± 0.9 Ma for the granodiorite and 113.5 ± 1.1 Ma for the alkali feldspar granite, with 103.2 ± 0.9 Ma for the Type 2 MMEs. Inherited ages of 117.0 ± 2.0 Ma and 119.8 ± 1.1 Ma seem to present in the former two samples. Similarities of mineral chemistry and isotopic composition among the MMEs-host pairs as well as the younger age of MMEs suggest that MMEs of Xiaojiang-Liangnong complexes most likely represent mixing/mingling products formed as a consequence of the intrusion of basaltic magma into the host granitoids under different cooling conditions. Judging from the presence of inherited zircon ages, the composition gap between high-Ti and low-Ti biotite in granodiorite and alkali feldspar granite, and lower zircon saturation temperatures for the host granitoids (calculated as 787°C and 763°C, respectively, for these two rock types), origin of the LYI-type granitoids in the Xiaojiang-Liangnong complexes is related to partial melting of different sources, with the preceding alkali feldspar granite derived from more quartzofeldspathic and later granodiorite, from more mafic sources. [ABSTRACT FROM AUTHOR]

In northeast Taiwan, many areas are affected by various tectonic forcings. Some areas appear to have a subsidence tendency, whereas others reflect uplift activities on the surface, due to tectonic northward compressive forcing growth and decline. Owing to the presence of widespread mountain areas, limited geodetic surveys in the field have made data scarce in the study area in the past decades. The distribution of the geomorphic indices, which were calculated along the river channels, were used to analyze the activities on a regional scale in this study. The long-term landscape evolution of drainage basins can record topographic changes through the river channels. By calculating the location and drop height of knickpoint in the river longitudinal profile, as well as the spatial distribution of the normalized steepness index ( Ksn ) value, it is possible to comprehensively discuss the perturbations that were caused by possible factors in river channels. Our results from the geomorphic indices synthetically suggest that the river channel of drainage basins is mainly influenced by the perturbations such as geological structures, tectonic activity, various lithologies, potential ruptures. In the study area, tectonic forcing act on a large area from north to south, which is reflected in the long-term incision of the river into the bedrock. Moreover, the potential ruptures on the surface may also induce displacement in the local area. [ABSTRACT FROM AUTHOR]

In this paper, we have successfully developed and fabricated self-aligned Si/Ge T-gate poly-Si thin-film transistors (Si/Ce T-gate TFTs) with a thick gate oxide at the gate edges near the source and drain for the first time. The Si/Ge T-gate was formed by selective wet etching of Ge gate layer. The thick gate oxide layer at the gate edges and passivation oxide layer were deposited simultaneously in passivation process. The thick gate oxide at the gate edges effectively reduces the drain vertical and lateral electric fields without additional mask, lightly doped drain, spacer, or subgate bias. The Si/Ge T-gate TFTs not only reduce the OFF-state leakage current but also maintain a high ON-state current. Experimental results show that the Si/Ge T-gate TFTs have low OFF-state leakage currents, improved ON/OFF current ratio, and more saturated output characteristics compared with conventional TFTs. [ABSTRACT FROM AUTHOR]

The northeast region of Taiwan has experienced a stress transition from the compressive collision to the extension induced from the Ryukyu subduction system in a post-collisional orogenic belt. In order to clarify when the extensional stage began and how the cooling and exhumation history varied with the transition of tectonic stress, apatite and zircon fission-track ages on the granitic gneiss in northern Tananao Complex were collected from a ~2700 m high sub-vertical profile. The exhumation rate was estimated as ~4 mm yr-1 since 4.1 - 3.0 Ma using previous biotite 40Ar-39Ar ages with an assumed uniform geothermal gradient. During the period of 1.5 - 0.2 Ma, the exhumation rate remained at 2.3 - 1.6 mm yr-1, evidenced by the similar slopes for apatite and zircon in the age-elevation relationship (AER). The decrease in exhumation occurred in between 3.0 and 1.5 Ma is interpreted as the onset of the extensional impact into NE Taiwan from the Ryukyu subduction zone. After ~0.2 Ma, the intercepts of apatite AER suggest that exhumation accelerated to ~5 mm yr-1 at the mountain range but was steady at the valley bottom. The offset in ages of the vertical profile is supportive of the normal faulting at the shallow crust. The accelerating cooling with the steady exhumation from 1.5 - 0.2 Ma implies the increase in paleogeothermal gradient with time. The paleogeothermal gradients are estimated to be over 100°C km-1 after 1.5 Ma, suggesting that the Hoping area possesses heat sources induced from the complex tectonic configuration. However, the modern geotherm is relatively low and may be influenced by the water circulation near surface. [ABSTRACT FROM AUTHOR]