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Translucent eggshells negatively affect the appearance of eggs and decrease their economic value. Translocation and accumulation of water from the contents to the shells of eggs are frequent occurrences. Causes of translucent eggshell formation have been investigated, but the primary reason is uncertain. In previous studies, scientists have found that the thickness of the eggshell membrane was significantly different between translucent and opaque eggs. However, there are some conflicts among studies. We performed 2 experiments with 3 breeding flocks of chickens to target the reasons for egg translucence. In experiment 1, eggs of 1,024 Brown-Egg Dwarf Layers (DWL) were used. Approximately 1,600 eggs were collected over 2 consecutive days. They were stored for 3 days, and then 120 translucent and 120 opaque eggs were selected for measurement of egg quality traits and weight loss over several weeks. In experiment 2, we used DWL and White Leghorn pure line (WLL) for assessment of eggshell ultrastructure and membrane traits. We chose 120 translucent and 120 opaque eggs from 3,500 DWL eggs and 125 translucent and 125 opaque eggs from 5,028 WLL eggs. The results are as follows: (1) translucent eggs had greater eggshell strength and lower ultimate failure stress of shell membrane than opaque eggs in both DWL and WLL groups, (2) translucent eggs had thicker shells and thinner shell membranes than opaque eggs in DWL, (3) no significant differences were found in either gas pore or bubble pore traits between translucent and opaque eggs in either line, and (4) no significant differences were detected in internal egg quality or weight loss between translucent and opaque eggs in either line. In summary, the present study suggests that variations in both eggshells and shell membrane structures are implicated in the formation of translucent eggs.

Thirty-three samples, including 22 eclogites, collected from the Dabie ultrahigh-pressure (UHP) metamorphic belt in eastern China, have been studied for seismic properties. Compressional (V p ) and shear wave (V s ) velocities in three mutually perpendicular directions under hydrostatic pressures up to 1.0 GPa were measured for each sample. At 1.0 GPa, V p (7.5-8.4 km s )1 ), V s (4.2-4.8 km s )1 ), and densities (3.2-3.6 g cm )3 ) in the UHP eclogites are higher than those of UHP orthopyroxenite (7.3-7.5 km s )1 , 4.1-4.3 km s )1 , 3.2-3.3 g cm )3 , respectively) and HP eclogites (7.1-7.9 km s )1 , 4.0-4.5 km s )1 , 3.1-3.5 g cm )3 , respectively). Kyanitites (with 99.5% kyanite) show extremely high velocities and density (9.37 km s )1 , 5.437 km s )1 , 3.581 g cm )3 , respectively). The eclogites show variation of V p -and V s -anisotropy up to 9.70% and 9.17%, respectively. PoissonÕs ratio (r) ranges from 0.218 to 0.278 (with a mean of 0.255) for eclogites, 0.281-0.298 for granulites and 0.248 to 0.255 for amphibolites. The r values for serpentinite (0.341) and marble (0.321) are higher than for other lithologies. The elastic moduli K, G, E of kyanitite were obtained as 163, 102 and 253 GPa, respectively. The V p and density of representative UHP metamorphic rocks (eclogite & kyanitite) were extrapolated to mantle depth (15 GPa) following a reasonable geotherm, and compared to the one dimension mantle velocity and density model. The comparison shows that V p and density in eclogite and kyanitite are greater than those of the ambient mantle, with differences of up to DV p > 0.3 km s )1 and Dq > 0.3-0.4 g cm )3 , respectively. This result favours the density-induced delamination model and also provides evidence in support of distinguishing subducted high velocity materials in the upper mantle by means of seismic tomography. Such ultra-deep subduction and delamination processes have been recognized by seismic tomography and geochemical tracing in the postcollisional magmatism in the Dabie region.

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In this paper, the analysis of faults with different scales and orientations reveals that the distribution of fractures always develops toward a higher degree of similarity with faults, and a method for calculating the multiscale areal fracture density is proposed using fault-fracture self-similarity theory. Based on the fracture parameters observed in cores and thin sections, the initial apertures of multiscale fractures are determined using the constraint method with a skewed distribution. Through calculations and statistical analyses of in situ stresses in combination with physical experiments on rocks, a numerical geomechanical model of the in situ stress field is established. The fracture opening ability under the in situ stress field is subsequently analyzed. Combining the fracture aperture data and areal fracture density at different scales, a calculation model is proposed for the prediction of multiscale and multiperiod fracture parameters, including the fracture porosity, the magnitude and direction of maximum permeability and the flow conductivity. Finally, based on the relationships among fracture aperture, density, and the relative values of fracture porosity and permeability, a fracture development pattern is determined.

A transfer zone is a kind of structure that is produced to conserve deformation of a fault structure on both sides. Increasing numbers of transfer zones are being identified in rift basins, which are areas of petroleum accumulation and potential exploration targets. This paper provides a numerical simulation method for the genesis and development of transfer zones based on geomechanical modeling. On the basis of three-dimensional (3-D) seismic interpretation, using the Tongcheng fault as an example, the fault activity parameter and fault activity intensity index were established to quantitatively characterize the difference in fault activity on the two sides of a transfer zone. A geomechanical model was developed for a transfer zone in a rift basin, and the structural characteristics and genetic mechanism of a convergent fault were studied using paleostress and strain numerical simulations. Affected by different movements of boundary faults and basement faults, the evolution of the Tongcheng fault can be divided into three stages: (1) during the Funing period, which was the main development period of compound transfer faults, the activity, stress, and strain of the fault blocks on either side of the Tongcheng fault were obviously different; (2) during the Dainan period, which was the development stage of inherited compound transfer faults, the northern part of the Tongcheng area underwent local compression, and the T3 anticline began to form; and (3) during the Sanduo period, the Tongcheng fault experienced right-lateral strike-slip activity, where the activity showed two stages of change, first increasing and then decreasing, and the Tongcheng fault anticline developed. The superposition of multiple complex tectonic movements produced a transfer zone that has both strike-slip and extensional fault properties. The geomechanical model in this paper provides important insights for analyzing the evolution of transfer zones in rift basins.

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