ALBERT

Description: The Changning MS6.0 earthquake and its moderate to strong aftershocks, which occurred in the axial area of Changning anticline, exhibit different features with the moderate to strong earthquakes that occurred in the southern syncline area nearby, although these two areas are only a dozen kilometers away. Whether this difference is only caused by different fault structures, or caused by local change is still a matter of debate. In order to answer this question, basing on the correction of small earthquake location and seismic velocity structure through double-difference tomography inversion, this paper determined the fine structure of the crustal stress field by using comprehensive focal mechanism solutions, and analyzed its mechanical consistency with the focal mechanism solutions of moderate to strong earthquakes. It is found that for the different subareas of Changning area, the maximum principal stress remains horizontal, and its azimuth remains almost East-West oriented although it has a small clockwise rotation from north to south; meanwhile, the stress regime exhibit a significant local change, which is thrust stress regime for the axial area of Changning anticline, against strike-slip stress regime for the southern syncline area. The stress fields in these two subareas highly accord with the focal mechanism solutions of moderate to strong earthquakes in the corresponding area, but poorly accord with, or even contradict that in the non-corresponding area, which indicates that the local stress change of stress field is the necessary mechanical basis for the complex seismicity behavior in Changning area. Additional rock mechanics analysis points out that lateral difference of Poisson's ratio of rock is probably the main cause of this local change of stress field. This paper also discusses the seismogenic fault structure of Changning MS6.0 earthquake sequence, and suggests the activation of the basement fault(s) in the depth range of 6 to 9 km in the axial area of Changning anticline driven by regional stress field is the potential cause of the occurrence of Changning MS6.0 earthquake sequence.

Description: For a long time， with the continuous expansion of the oil and gas genesis theory and the increasing global demand for clean energy， hydrogen， as an important link connecting the theory of inorganic and organic hydrocarbon generation， as well as a promising clean energy， has gradually attracted widespread academic attention. The genesis of hydrogen in natural gas is relatively complex and diverse. According to its reaction mechanism， it can be divided into two categories： inorganic and organic. Inorganic genesis is mainly earth degassing， water rock reaction and water radiation decomposition， while organic genesis is dominated by biological action and organic matter pyrolysis. At present， hydrogen isotope and geochemical characteristics of associated gases are mainly used to identify the origin of hydrogen. However， due to the complex and diverse sources of hydrogen and its active chemical properties， it is still unable to identify the origin of hydrogen systematically and accurately. Due to the extensive genesis of hydrogen， natural gas with different hydrogen concentrations has been found in different geological conditions around the world， and the hydrogen content varies greatly （0.1%-99%）. Hydrogen can participate in hydrocarbon generation in Fischer Tropsch synthesis as a reducing agent， and also can be used as a hydrogen source to improve the hydrocarbon yield during the thermal evolution of organic matter. Therefore， the existence of hydrogen may extend the lower limit of deep gas exploration and development. Based on the systematic summary of the genetic mechanism and distribution of hydrogen， this paper discusses the energy significance of hydrogen in natural gas， and provides a reference for the future research on hydrogen rich natural gas resources.

Description: This project started in October 2015 with a crazy idea : prepare and submit a funding application for an international, multidisciplinary and non-traditional scientific outreach project… within the next 48 hours. Well, it worked out. A group of highly motivated young researchers from Canada and Europe united to combine arts and science and produce a series of outreach comic strips about permafrost (frozen ground). The aim of the project is to present and explain scientific research conducted across the circumpolar Arctic, placing emphasis on field work and the rapidly changing northern environment. The target audience is kids, youth, parents and teachers, with the general goal of making permafrost science more fun and accessible to the public. Because guess what : permafrost represents an area of more than twenty million km2 in the Northern Hemisphere, a huge area. As the climate warms, permafrost thaws and becomes unstable for houses, roads and airports. This rapid thawing of previously frozen ground also disrupts plant and animal habitats, impacts water quality and the ecology of lakes, and releases carbon into the atmosphere as greenhouse gases, making climate change even stronger. Hence permafrost and its response to climate change concerns us all. The project received initial support from the International Permafrost Association (IPA) as a targeted ‘Action Group’, and since then several other sponsors have joined the project. Here we are, now, two years after this first idea. What you are about to read is the result of an iterative process of exchanging ideas between artists and scientists. We first made an application call and received 49 applications from artists in 16 countries. Through a formal review process, we then selected two artists to work on this project: Noémie Ross from Canada, and Heta Nääs from Finland. With input from scientists, Noémie and Heta created fantastic cartoons that explain some of the changes happening to the environment in permafrost areas, how they affect people and wildlife, and what scientists are doing to better understand these changes to help people find innovative ways to adapt. We wish everyone plenty of fun reading this booklet and we would like to thank all those who supported this project.