Can Eurasia Experience a Cold Winter under a Third-Year La Ni?a in 2022/23?

The Northern Hemisphere(NH) often experiences frequent cold air outbreaks and heavy snowfalls during La Ni?a winters. In 2022, a third-year La Ni?a event has exceeded both the oceanic and atmospheric thresholds since spring and is predicted to reach its mature phase in December 2022. Under such a significant global climate signal, whether the Eurasian Continent will experience a tough cold winter should not be assumed, despite the direct influence of mid-to high-latitude,large-scale atmospheric ...     

Planetary wave reflection and its impact on tropospheric cold weather over Asia during January 2008

Reflection of stratospheric planetary waves and its impact on tropospheric cold weather over Asia during January 2008 were investigated by applying two dimensional Eliassen-Palm （EP） flux and three-dimensional Plumb wave activity fluxes.The planetary wave propagation can clearly be seen in the longitude-height and latitude-height sections of the Plumb wave activity flux and EP flux,respectively,when the stratospheric basic state is partially reflective.Primarily,a wave packet emanating from Baffin Island/coast of Labrador propagated eastward,equatorward and was reflected over Central Eurasia and parts of China,which in turn triggered the advection of cold wind from the northern part of the boreal forest regions and Siberia to the subtropics.The wide region of Central Eurasia and China experienced extreme cold weather during the second ten days of January 2008,whereas the extraordinary persistence of the event might have occurred due to an anomalous blocking high in the Urals-Siberia region.     

Source mechanism of strong aftershocks (M_s≥5.6) of the 2008/05/12 Wenchuan earthquake and the implication for seismotectonics

Dozens of >M5, hundreds of >M4, and much more >M3 aftershocks occurred after the 2008/05/12 Wenchuan earthquake, which were well recorded by permanent and portable seismic stations. After relocated with P arrival, the >M3 aftershocks show two trends of distribution, with most of the aftershocks located along the north-east strike consistent with Longmenshan fault system, yet there is a north-west trend around the epicenter. It seems that substantially more aftershocks occur in regions with crystalline bedro...     

开封古城不同朝代文化层重金属积累与污染分析

开封古城黄泛沉积形成的“城摞城”奇观为文化层重金属积累与污染分析提供难得的材料。在开封市城区（师专钻孔和医专钻孔）和郊区（金明钻孔）分别获取25 m连续岩芯,大部分按10 cm间隔分样,共获得657个沉积物样品。用ICP-MS和AFS方法测定样品Pb、Cd、Cu、Zn、Hg、As、Ni、Cr和Co含量。结合地层¹⁴C年代数据、考古发掘及历史文献记载,建立不同朝代文化层年代框架,开展文化层重金属积累与污染分析。结果表明：师专、医专和金明钻孔均存在战国、宋金、明早期、明中期、明晚期和清代6个文化层。文化层大部分重金属发生不同程度富集,以Hg富集最为明显,城区钻孔明早期以前文化层达到强富集至极强富集水平。绝大多数文化层发生了重金属轻度至中度污染,中度污染发生在城区钻孔的宋金文化层。城区钻孔的最主要污染重金属是Hg,其次是Cu、Pb和Zn;郊区钻孔的主要污染重金属是Cd、Cr、Hg和Pb。不同朝代文化层重金属污染程度与其人口密度呈正相关。明早、中、晚期文化层污染程度逐渐减轻的现象可能与明朝开封城复兴与频繁的黄河泛滥有关。     

New Approaches and Markers for Identifying Secondary Biogenic Coalbed Gas

According to the adsorption-desorption characteristics of coalbed gas and analysis of various experimental data, this paper proposes that the generation of secondary biogenic gas (SBG) and its mixing of with the residual thermogenic gas at an early stage inevitably lead to secondary changes of the thermogenic gas and various geochemical additive effects. Experimental results also show that the fractionation of the carbon isotope of methane of coal core desorption gas changes very little; the δ13C1 value of the mixed gas of biogenic and thermogenic gases is between the δ13C1 values of the two “original” gases, and the value is determined by the carbon isotopic compositions and mixing proportions of the two “original” methanes. Therefore this paper proposes that the study on the secondary changes of the thermogenic gas and various additive effects is a new effective way to study and identify SBG. Herein, a systematic example of research on the coalbed gas (Huainan coalbed gas) is further conducted, revealing a series of secondary changes and additive effects, the main characteristics and markers of which are: (1) the contents of CO2 and heavy-hydrocarbons decrease significantly; (2) the content of CH4 increases and the gas becomes drier; (3) the δ13C and δD values of methane decrease significantly and tend to have biogenetic characteristics; and (4) the values of δ13C2 and δ13CCO2 grow higher. These isotopic values also change with the degradation degrees by microbes and mixing proportions of the two kinds of gases in different locations. There exists a negative correlation between the δ13C1 vs δ13CCO2 values. The △δ13CC2–C1 values obviously become higher. The distributions of the △δ13CCO2–C1 values are within certain limits and show regularity. There exist a positive correlation between the N2 versus Ar contents, and a negative correlation between the N2 versus CH4 contents, indicating the down forward infiltration of the surface water containing air. These are important markers of the generation and existence of SBG.     

Variation of alkaline phosphatase activity in sediments of shrimp culture ponds and its relationship with the contents of C,N and P

1Introduction Activities of extracellular enzymes can serve as theindicators of organic matter content.Enzyme assayinghas been used in the analyses of dissolved organic ma-terials in aquatic environments(Chrost,1991),massloss of plant litter in terrestrial systems(Sinsabaughet al.,1992;Sinsabaugh et al.,1994),processing ofpaniculate and dissolved organic carbon(POC,DOC)in streams(Sinsabaugh and Findlay,1995;Findlayet al.,1998),and processing of particulate organicmatter(POM)in wetlands(J…     

Distribution of Landslides in Baoshan City, Yunnan Province, China

Using Google Earth software as a platform, this study has established an integrated database of both old and new landslides in Baoshan City, Yunnan Province, China, and analyzed their development characteristics together with distribution rules, respectively. Based on the results, a total of 2 427 landslides occurred in the study area, including 2 144 new landslides and 283 old landslides, with a total area of about 104.8 km². The new landslides are mostly in small-scales with an area less than 10 000 m², while the area of individual old landslide is mostly larger than 10 000 m². By analyzing the relationship between the two types of landslides and eight impact factors (i.e., elevation, slope angle, slope aspect, slope position, lithology, fault, regional Peak Ground Acceleration (PGA), and average annual rainfall), the different individual influencing factors, distribution regularities and mechanisms of the two types of landslides are revealed. In detail, the main influencing factors of new landslides are elevation, slope angle, slope aspect, slope position, lithology, regional PGA and average annual rainfall, while the influencing factors of old landslides are mainly elevation, slope angle, and lithology. This study provides basic data and support for landslide assessment and further disaster reduction in Baoshan City. Besides, it also provides new constraints in deeply understanding the effect of different topographic and geological conditions, historical earthquakes, rainfall and other factors on the occurrence mechanisms of both new landslides and old landslides.     

巴伦支海中的大撞击坑

一个大的地球外物体与地球碰撞导致了白垩纪-第三纪边界群体的灭绝，这种假设使人们对碰撞是群体灭绝主要原因之一的可能性产生极大兴趣。然而，地球上较少的撞击坑记录不能令人满意地证实所提出的这个假设，因为撞击坑被侵蚀掉，或被俯冲消失。     

Naquite,FeSi, a New Mineral Species from Luobusha,Tibet, Western China

A new mineral species, named naquite(FeSi), is found in the podiform chromitites of the Luobusha ophiolite in Qusong County, Tibet, China. The detailed composition is Fe 65.65, Si 32.57 and Al 1.78 wt%. The mineral is cubic, space group P213. The irregular crystals range from 15 to 50 μm in diameter and form an intergrowth with luobusaite. Naquite is steel grey in color, opaque, with a metallic lustre and gives a grayish-black streak. The mineral is brittle, has a conchoidal fracture and no apparent cleavage. The estimated Mohs hardness is 6.5, and the calculated density is 6.128 g/cm3. Unit-cell parameters are a 4.486 (4) ?, V 90.28 (6) ?3, Z=4. The five strongest powder diffraction lines [d in ? (hkl) (I/I0)] are: 3.1742 (110) (40), 2.5917(111) (43), 2.0076 (210) (100), 1.8307 (211) (65), and 1.1990 (321) (36). Originally called ‘fersilicite’, the species and new name have now been approved by the CNMNC (IMA 2010–010).     

从死海的约旦河三角洲崩滑沉积物中得到的杰里科地震证据

从死海的约旦河三角洲崩滑沉积物中得到的杰里科地震证据Ｔ．Ｍ．Ｎｉｅｍｉ等沿死海一约旦转换板块边界的断层活动是Ｂｉｂｌｉｃａｌ和较近代时期圣地地震的主要原因。由于有感记录不确切和过于夸张，所以除编纂了几个地震目录外，几乎没做过将断裂段归因于历史地震的尝...