Dating submarine landslides using the transient response of gas hydrate stability

Submarine landslides are prevalent on the modern-day seafloor, yet an elusive problem is constraining the timing of past slope failure. We present a novel age-dating technique based on perturbations to underlying gas hydrate stability caused by slide-impacted seafloor changes. Using three-dimensional (3-D) seismic data, we mapped an irregular bottom simulating reflection (BSR) underneath a submarine landslide in the Orca Basin, Gulf of Mexico. The irregular BSR mimics the pre-slide seafloor geometry rather than the modern bathymetry. Therefore, we suggest that the gas hydrate stability zone (GHSZ) is still adjusting to the post-slide sediment temperature. We applied transient conductive heat-flow modeling to constrain the response of the GHSZ to the slope failure, which yielded a most likely age of ca. 8 ka, demonstrating that gas hydrate can respond to landslides even on multimillennial time scales. We further provide a generalized analytical solution that can be used to remotely date submarine slides in the absence of traditional dating technique

Prognostic resources of mineral deposits by geophysical methods

In the framework of non-equilibrium statistical thermodynamics a relation between the concentration of component of the ore to its physical properties.On the basis of this communication formulas for calculation of the differentiated and predicted stocks of deposits of minerals are received on the basis of the geophysical data. Methods of magnetic investigation, electric investigation, gravitational investigation and seismic prospecting, and also nuclear physical methods are considered. A comparison of the calculated expected resources with proven for a number of fields in Kazakhstan. The proposed method allows to perform predictive assessment of stocks of deposits in the early stages of prospects with using the results of geophysical methods, while it has a rapidity and to be sufficiently accurate. Non-equilibrium thermodynamics, geophysical methods, and estimated resources, deposits of minerals

Variations in Gas and Water Pulses at an Arctic Seep: Fluid Sources and Methane Transport

Methane fluxes into the oceans are largely dependent on the methane phase as it migrates upward through the sediments. Here we document decoupled methane transport by gaseous and aqueous phases in Storfjordrenna (offshore Svalbard) and propose a three-stage evolution model for active seepage in the region where gas hydrates are present in the shallow subsurface. In a preactive seepage stage, solute diffusion is the primary transport mechanism for methane in the dissolved phase. Fluids containing dissolved methane have high Sr-87/Sr-86 ratios due to silicate weathering in the microbial methanogenesis zone. During the active seepage stage, migration of gaseous methane results in near-seafloor gas hydrate formation and vigorous seafloor gas discharge with a thermogenic fingerprint. In the postactive seepage stage, the high concentration of dissolved lithium points to the contribution of a deeper-sourced aqueous fluid, which we postulate advects upward following cessation of gas discharge

Рецидивирующий респираторный папилломатоз с вовлечением легких и малигнизацией

Recurrent respiratory papillomatosis (RP) is one of the most challenging benign tumors of the upper and lower respiratory tract. Dissemination of the tumor process and damage to the lung tissue not only increase the likelihood of malignancy, but also complicate the choice of treatment tactics, largely limit the surgical options, and necessitate a multidisciplinary approach.Methods. The enrolled patients with RP have been treated (n = 190) in the Federal State Budgetary Educational Institution of Higher Education “Academician I.P.Pavlov First St. Petersburg State Medical University”, Ministry of Healthcare of Russian Federation, from 2000 to the present. Changes in the lung tissue were detected in 5 (2.6%) patients (2 men and 3 women) with aggressive course of the disease.Results. The clinical characteristics of patients and the outcomes of lung damage in RP are presented. Four patients had malignant transformation of the tumor into verrucous carcinoma of the upper third of the trachea with invasion into the soft tissues of the neck (n = 1) or malignant degeneration of the lesion in the lung parenchyma (n = 3).Conclusion. The presented rare observations suggest polymorphism of clinical and radiological symptoms of papillomatous damage to the tracheobronchial system and lungs.Рецидивирующий респираторный папилломатоз (РРП) является одной из сложнейших проблем среди доброкачественных опухолей верхних и нижних дыхательных путей. Диссеминация опухолевого процесса и поражение легочной ткани не только создают вероятность малигнизации, но и усложняют выбор тактики лечения и во многом ограничивают хирургические возможности, обусловливая необходимость мультидисциплинарного подхода. Материалы и методы. С 2000 г. по настоящее время пациенты с РРП (n = 190) получали лечение в Федеральном государственном бюджетном образовательном учреждении высшего образования «Первый СанктПетербургский государственный медицинский университет имени академика И.П.Павлова» Министерства здравоохранения Российской Федерации. У 5 (2,6 %) больных (2 мужчин и 3 женщины) с агрессивным течением заболевания выявлены изменения в легочной ткани. Результаты. Представлена клиническая характеристика пациентов и исходы течения поражения легких при РРП. У 4 пациентов установлена малигнизация опухоли в виде веррукозной карциномы верхней трети трахеи с прорастанием в мягкие ткани шеи (n = 1) и злокачественное перерождение очага в паренхиме легких (n = 3). Заключение. По данным представленных редких наблюдений продемонстрирован полиморфизм клинической и рентгенологической симптоматики поражения трахеобронхиальной системы и легких папилломатозным процессом

Extensive release of methane from Arctic seabed west of Svalbard during summer 2014 does not influence the atmosphere

© 2016. American Geophysical Union. All Rights Reserved. We find that summer methane (CH4) release from seabed sediments west of Svalbard substantially increases CH4 concentrations in the ocean but has limited influence on the atmospheric CH4 levels. Our conclusion stems from complementary measurements at the seafloor, in the ocean, and in the atmosphere from land-based, ship and aircraft platforms during a summer campaign in 2014. We detected high concentrations of dissolved CH4 in the ocean above the seafloor with a sharp decrease above the pycnocline. Model approaches taking potential CH4 emissions from both dissolved and bubble-released CH4 from a larger region into account reveal a maximum flux compatible with the observed atmospheric CH4 mixing ratios of 2.4-3.8 nmol m-2 s-1. This is too low to have an impact on the atmospheric summer CH4 budget in the year 2014. Long-term ocean observatories may shed light on the complex variations of Arctic CH4 cycles throughout the year.The project MOCA- Methane Emissions from the Arctic OCean to the Atmosphere: Present and Future Climate Effects is funded by the Research Council of Norway, grant no.225814 CAGE – Centre for Arctic Gas Hydrate, Environment and Climate research work was supported by the Research Council of Norway through its Centres of Excellence funding scheme grant no. 223259. Nordic Center of Excellence eSTICC (eScience Tool for Investigating Climate Change in northern high latitudes) funded by Nordforsk, grant no. 57001

On the study of the effects of sea views, greenery views and personal characteristics on noise annoyance perception at homes

Noise annoyance has caused significant adverse impacts on human beings and numerous efforts have been spent on mitigating annoyance problems. Natural greenery has been shown to be able to moderate annoyance problems at home but this conclusion was drawn without properly controlling the potential confounding factors. Furthermore, few have explored the moderation effect of a sea view. Accordingly, this study formulated a multivariate model to examine the impacts of natural views as well as personal characteristics on annoyance perception. A housing estate was selected in Hong Kong as the survey site for which some of the residents were exposed to greenery views, sea views, or both from their homes. Eight hundred and sixty-one responses were collected via questionnaire surveys and analyzed using an ordered logit model. The results suggest that both a greenery view and a sea view can moderate annoyance responses. Several individual’s personal characteristics are found to affect individuals’ annoyance perception. The duration of time spent daily at home is shown to have an influence on the moderation impact exerted by a greenery view, while the age of an individual is shown to have an influence on noise moderation effect exerted by a sea view.Department of Building Services Engineerin