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161.
This paper is intended to be a constructive discussion of Fiket et al. (2017, Geostandards and Geoanalytical Research , 41 , 123–135), who dealt with the determination of major, trace and rare earth elements in several sediment and soil certified reference materials. In the present author's view, the paper by Fiket et al. (2017) suffers from a lack of reference to several publications in which somewhat similar results had already been reported. The present contribution therefore provides a comparison of previously published results with those of Fiket et al. for the CRMs soil NCS DC 77302 (GBW 07410), stream sediment NCS DC 73309 (GBW 07311), marine sediments MESS‐3 and NCS DC 75301 (GBW 07314) and estuarine sediment IAEA‐405. It is argued that this fuller consideration (a) allows critical evaluation of the quality of the results presented by Fiket et al. and (b) highlights the advantages of their work. Finally, attention is drawn to the (possible or real) problems that can arise during simultaneous determination of multiple trace elements.  相似文献   
162.
Anorthositic series apatites of the Duluth Complex, Minnesota, USA, have high spontaneous fission‐track densities of up to ~107 cm–2 and a homogeneous age of ~900 Ma, allowing high‐precision fission‐track dating based on LA–ICP–MS U analysis. Absolute fission‐track dating, track‐length measurement and chemical composition analysis were performed to evaluate a cooling history, which is essential for age reference materials. Preliminary inverse modelling for a sample with a shortened track‐length distribution yielded a monotonic cooling history from ~100°C at 925 Ma. The apatites incur an over‐etching problem when employing the commonly used etching protocol involving 5.5 M HNO3.  相似文献   
163.
164.
The future changes in the relationship between the South Asian summer monsoon (SASM) and the East Asian summer monsoon (EASM) are investigated by using the high-emissions Shared Socioeconomic Pathway 5-8.5 (SSP5- 8.5) experiments from 26 coupled models that participated in the phase 6 of the Coupled Model Intercomparison Project (CMIP6). Six models, selected based on their best performance in simulating the upper- and lower-level pathways related to the SASM-EASM teleconnection in the historical run, can capture the positive relationship between the SASM and the rainfall over northern China. In the future scenario, the upper-level teleconnection wave pattern connecting the SASM and the EASM exhibits a significant weakening trend, due to the rainfall anomalies decrease over the northern Indian Peninsula in the future. At the lower level, the western North Pacific anticyclone is projected to strengthen in the warming climate. The positive (negative) rainfall anomalies associated with positive (negative) SASM rainfall anomalies are anticipated to extend southward from northern China to the Yangtze-Huai River valley, the Korea Peninsula, and southern Japan. The connection in the lower-level pathway may be strengthened in the future.  相似文献   
165.
The Paris Agreement (PA) emphasizes the intrinsic relationship between climate change and sustainable development (SD) and welcomes the 2030 agenda for the global Sustainable Development Goals (SDGs). Yet, there is a lack of assessment approaches to ensure that climate and development goals are achieved in an integrated fashion and trade-offs avoided. Article 6.4 of the PA introduces a new Sustainable Mitigation Mechanism (SMM) with the dual aim to contribute to the mitigation of greenhouse gas emissions and foster SD. The Kyoto Protocol’s Clean Development Mechanism (CDM) has a similar objective and in 2014, the CDM SD tool was launched by the Executive Board of the CDM to highlight the SD benefits of CDM activities. This article analyses the usefulness of the CDM SD tool for stakeholders and compares the SD tool’s SD reporting requirements against other flexible mechanisms and multilateral standards to provide recommendations for improvement. A key conclusion is that the Paris Agreement’s SMM has a stronger political mandate than the CDM to measure that SD impacts are ‘real, measurable and long-term’. Recommendations for an improved CDM SD tool are a relevant starting point to develop rules, modalities, and procedures for SD assessment in Article 6.4 as well as for other cooperative mitigation approaches.

POLICY RELEVANCE

Research findings are relevant for developing the rulebook of modalities and procedures for Article 6.4 of the Paris Agreement, which introduces a new mechanism for mitigation of greenhouse gas emissions and sustainable development. Lessons learnt from the CDM SD tool and recommendations for enhanced SD assessment are discussed in context of Article 6 cooperative approaches, and make a timely contribution to inform negotiations on the rulebook agreed by the Conference of the Parties serving as the Meeting of the Parties to the Paris Agreement.  相似文献   

166.
为了解2021-09-16四川泸县MS6.0地震的发震机理,加强对四川盆地内地震活动性的认识,基于四川及周边地区地震台网的宽频带地震资料,利用CAP方法反演获得泸县地震的震源机制解和矩心深度;同时,基于震前四川盆地内155个震源机制解,利用MSATSI程序反演得到泸县地震震前四川盆地内的构造应力场。结果显示,泸县地震矩心深度为3 km,矩震级为MW5.3,滑动性质为纯逆冲。震中附近震前构造应力最大主压应力和中间主压应力都近乎水平,最大主压应力在震中附近走向101°,此构造应力状态下,优势滑动断层为纯逆冲性质,与泸县地震震源机制一致。根据震源位置和性质、震前构造应力场及震中附近的断层性质推测,泸县地震发震断层不是华蓥山断裂,而是其分支和余脉之间极浅的盖层滑脱型断层。  相似文献   
167.
基于河北区域数字地震台网资料,采用CAP波形反演方法计算2020-07-12唐山MS5.1地震的震源机制解,同时采用sPL深度震相方法对震源深度进行精确测定。结果显示,唐山MS5.1地震震源机制解节面Ⅰ走向143°、倾角83°、滑动角-14°,节面Ⅱ走向235°、倾角76°、滑动角-173°;sPL深度震相方法测定的主震震源深度为14 km,与CAP波形反演方法的计算结果一致。结合地震序列分布特征、等震线形态、区域地质构造及深地震反射剖面等资料分析认为,节面Ⅱ为发震断层面,并推测此次地震的发震断层为唐山-古冶断裂。  相似文献   
168.
普宜地区位于上扬子腹地——四川盆地东南缘,区内晚三叠世碎屑岩记录了上扬子前陆盆地演化信息,是研究盆地东缘盆山耦合的理想对象.二桥组主要由三角洲平原-三角洲前缘相砂岩组成,交错层理恢复的物源主要来自东侧,砂岩岩屑主要由岩浆岩岩屑和变质岩岩屑组成,碎屑重矿物主要由锆石、电气石、金红石、白钛石、黄铁矿、锐钛矿、石榴子石、铬铁...  相似文献   
169.
SKB (Svensk Kärnbränslehantering AB) is responsible for all handling, transport and storage of the nuclear wastes outside the Swedish nuclear power stations. According to Swedish law, SKB is responsible for an R&D-programme needed to take care of the radwastes. The programme comprises, among others, a general supportive geo-scientific R&D and the Äspö Hard Rock Laboratory (HRL) for more in-situ specific tasks.

Sweden is geologically located in the Fennoscandian shield which is dominated by gneisses and granitoids of Precambrian age. The Swedish reference repository concept thus considers an excavated vault at ca. 500 m depth in crystalline rocks. In this concept (KBS-3), copper canisters with high level waste will be emplaced in deposition holes from a system of tunnels. Blocks of highly compacted swelling bentonite clay are placed in the holes leaving ample space for the canisters. At the final closure of the repository, the galleries are backfilled with a mixture of sand and bentonite. This repository design aims to make the disposal system as redundant as possible. Although the KBS-3 concept is the reference concept, alternative concepts and/or repository lay-outs are also studied. The main alternative, currently under development at SKB, is disposal in boreholes with depths of 4–5 km. The geoscientific research will to a great extent be guided by the demands posed by the performance and safety assessments, as well as the constuctability issues. Some main functions of the geological barrier are fundamental for the long-term safety of a repository. These are: bedrock mechanical stability, a chemically stable environment as well as a slow and stable groundwater flux. The main time-table for the final disposal of long-lived radioactive waste in Sweden foresees the final selection of the disposal system and site during the beginning of next decade.  相似文献   

170.
本文对1983年山东菏5.9级地震震中周围200km范围内8口井17个测地下流体观测资料,采用地下流体群体异常演化层次跟踪法,对菏治5.9级地震进行了中期,短期和短临三个时间尺度的震情预测,  相似文献   
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