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The polarizer film is an important component in the Thin-film-transistor liquid crystal displays (TFT-LCDs), which is a multilayer composite film developed by using dichromatic material stretching film technology. However, the polarizer film is liable to fail in hygrothermal circumstances. In this work, we analyzed a polarizer film shipped from China to Brazil that failed due to the ocean environment. By analyzing the structure, composition, and crystallinity of the polarizer film, Polyvinyl Alcohol (PVA) layer of the polarizer film has larger crystallinity, and there are bonding pores between the PVA layer and the Triacetyl Cellulose (TAC) layer. Under the action of the marine environment, the I3− ions in the PVA layer were released, resulting in the separation of PVA layer and TAC layer at the bonding pores, and then forming bright spots. Furthermore, through analyzing the marine environment and simulated environmental experiments, it was determined that the thermal environmental factor induces the release of I3− ions in the PVA layer. Finally, based on the failure process and failure mechanism of the polarizer, improvement measures to prevent the occurrence of bright spots of the polarizer are proposed. [ABSTRACT FROM AUTHOR]

Identifying seafloor methane seepage efficiently has important implications for assessing environmental impact, reducing the uncertainty of top seal integrity, understanding the petroleum system, and mitigating the drilling hazards due to shallow gas influx. Pore water geochemistry analyses suggest that the study area has an extremely high methane seepage flux and active methane anaerobic oxidation processes. However, geochemical data cannot provide details about the internal seepages. The geophysical dataset from the Western slope of Okinawa Trough, including 2D high-resolution seismic, sub-bottom profiles, and bathymetry, gives us a good opportunity to understand the detailed characteristics of methane seepages in this study. Geophysical data have revealed numerous methane seepage-related features such as seismic chimneys, pockmarks, submarine domes, and amplitude anomalies, including bright spots and enhanced reflections. Pockmarks and domes are often associated with seismic chimneys, indicating that fluid migration is important in their formation. The various geophysical expressions may represent different stages of methane seepage. Fluid quickly drains, causing severe sediment deformation and forming pockmarks, whereas domes may indicate the early stages of fluid discharge. Chimneys that do not extend to the seafloor may indicate that the venting is gradual and focused. Flares linked to domes or pockmarks may indicate that the fluid migration is active. Several factors triggered the existence of methane seepages on the Western slope of the Okinawa Trough, including tectonic setting, overpressure and rapid sedimentation.

The thickness of the Atlantic Equatorial segment sedimentary cover decreases with the distance from the continental source of mass removal and increases slightly with the distance from the Mid-Atlantic Ridge (MAR). Background sedimentation makes a small contribution to the total sedimentary volume near the continents and the major contribution in basins with the formation of sedimentary bodies with a thickness of no more than 500 m. Sedimentary bodies with a thickness up to 1000 m near MAR are the results of unloading of bottom currents near structural barriers in topography and in fault troughs. The total thickness tends to increase from north to south on the western flank of the MAR. The multidirectional spatial migration of the basement depressions filled with sediments is revealed. To the west of the MAR, contrasting acoustic stratification and tectonic deformations of sediments were found. To the east of the MAR, deformations are rare and expressed by piercing structures and normal faults. Anomalies of the "bright spot" type associated with local manifestations of magmatism forming aligned high-amplitude reflectors are revealed. Normal faulting in the passive parts of the transforms zones indicates the presence of local stretching, which is part of the simple shear paragenesis. In the troughs, sediment deposition from the bottom currents, which forms channel drifts, is revealed.

Studies of acoustic anomalies in the water column and seismoacoustic anomalies in the Quaternary sediments of Pechora sea and their relationship with deep hydrocarbon sources were conducted by the Institute of Oceanology of the Russian Academy of Sciences and the Geological Institute of the Russian Academy of Sciences in the 38th cruise of RV “Academik Nikolaj Strakhov” in 2018. Mapping of free gas manifestations presents an additional indicator of tectonic activity and the fault network frame, which provides the flow of fluids from deep horizons. Comparison of high-resolution seismic survey data with deep seismic survey data shows that the fluid in the upper part of the section is first accumulated under the bottom of Jurassic-Cretaceous sedimentary sequences, which are fluid-resistant. Local dislocations of fluid trap lead to further rise and redistribution of free gas in Quaternary sequences. Natural or artificial break of their integrity results in the release of gas into the water column from near-surface accumulations that were found in the form of “bright spot” anomalies on seismic-acoustic records. Mapping of sound scattering objects in the water column shows the degassing areas, which are usually located above the deep faults. “Bright spots” of free gas in the Quaternary sequences have a variety of shapes – multi-tiered and inclined. Gas breaks into the water column occur near the edges of these anomalies. Systematic mapping of the considered phenomena is a necessary element in the preparation of the area for industrial operation.

Thermal inertia is a key information to quantify the physical status of a planetary surface. We derive the thermal inertia of the surface of Ceres using spatially resolved data from the Dawn mission. For each location, this quantity can be constrained by comparing theoretical and observed diurnal temperature profiles from retrieved temperatures. We calculated Ceres's surface theoretical temperatures with a thermophysical model that provides temperature as a function of thermal conductivity and roughness, and we determined the values of those parameters for which the best fit with the observed data is obtained. Our results suggest that the area of crater Haulani displays thermal inertia values (up to 130–140 J·m−2·s−½·K−1) substantially higher than the very low to low values (from 1–15 to 50–60 J·m−2·s−½·K−1) derived for the overall surface of Ceres. The results are more ambiguous for the bright faculae located in the floor of crater Occator. Plain Language Summary: We have calculated Ceres's surface temperatures and we have compared them with the observations. We have used new high‐resolution data provided by the Dawn/National Aeronautics and Space Administration mission, which was launched in 2007 with the aim of studying two of the largest bodies of the Main Belt: Vesta and Ceres. Our results suggest that the surface is made of fine‐grained material, according to previous analysis made by other authors by using other independent data and methods. We have also studied two particular areas of Ceres that shows peculiar properties (albedo and/or chemical/physical structure). Key Points: The thermal inertia of the surface of Ceres has been derived using spatially resolved data from the Dawn missionThe Haulani crater appears to have a higher thermal inertia with respect to Ceres's averageThe average thermal inertia of the surface of Ceres appears to have low values (1–15 J·m−2·s−½·K−1) [ABSTRACT FROM AUTHOR]

Genuine hydrocarbon saturated post stack bright spots and the false ones have been discriminated using AVO and acoustic impedance attributes on the drill sites of three successful wells and delineated prospects. Class III type AVO anomaly and low acoustic impedance are associated with the hydrocarbon sands. Concurrent regions with bright spots, AVO effect and low acoustic impedance are identified as genuine bright spots indicating hydrocarbon sand while locations without the combination of the three indicators are interpreted as false bright spots depicting shales or wet sand. The presence of a bright spot, high acoustic impedance and the absence of an AVO effect indicate prospect 2 (Well A-4) to be a wet reservoir and shouldn't have been drilled. While Prospect 1, which exhibits a bright spot, good AVO effect and low acoustic impedance is interpreted as a hydrocarbon reservoir with a lateral extent of approximately 2 km and should be included in the next drilling program. This study has, therefore confirmed the use of AVO analysis in generating prospects and reducing risks connected with hydrocarbon exploration and development. [ABSTRACT FROM AUTHOR]