Field Measurement of Suction, Water Content, and Water Permeability

This paper presents a review of techniques for field measurement of suction, water content, and water hydraulic conductivity (permeability). Main problems in the use of field tensiometers are addressed and hints on how to improve tensiometer performance are given. Advantages and limitations of instruments for indirect measurement of suction including electrical conductivity sensors, thermal conductivity sensors, dielectric permittivity sensors, filter paper, and psychrometer are discussed. Techniques for water content measurement based on dielectric methods are then presented. These include time and amplitude domain reflectometry and capacitance. Finally, a brief overview of methods for measurement of water permeability in the field is presented.     

Inter sensor comparison between RESOURCESAT LISS III, LISS IV and AWiFS with reference to coastal landuse/landcover studies

Coastal zone assumes importance due to high productivity of ecosystems, man-made developmental activities, natural hazards and dynamic nature of the coast. As costal ecosystems are unique and fragile, understanding the impact of developmental activities on the sustainability of the coastal zone is very important. Remote sensing, because of repetitive and synoptic nature is an ideal tool for studying this. Time series data analyses for monitoring coastal zone require different type of sensors. Present study deals with atmospheric correction of satellite data, reflectance, selection of coastal features like, mudflat, mangroves, vegetated dune, coastal water, etc. and their inter-comparison using different sensor data of RESOURCESAT sensors. Reflectance values give better separateability for various coastal features in comparison to DN values. LISS IV can be used in place of LISS III or merged (LISS III + PAN) for long-term coastal zone studies.     

土钉抗拔承载力的原位试验研究

根据土钉现场抗拔试验数据,分析了钉材、浆液龄期等因素对土钉抗拔承载力的影响,建议了合理的下层土钉开挖时间。最后通过试验土钉抗拔力反算土体与锚固体的极限粘结强度,并与规范推荐值进行了比较。     

512铀矿床地浸条件及技术经济评价

本文应用铀矿普查及地浸试验中获取的资料，对５１２矿床地质构造、矿石物质成份、矿床水文地质、工程地质及自然经济地理等地浸条件及矿床技术经济条件进行了分析评价，认为５１２矿床地浸条件较好，地浸技术指标适中，用酸法地浸开采具有耗酸量少、成本低、经济效益好的特点。在今后的开采中，若能解决伴生元素Ｒｅ，Ｓｅ，Ｍｏ的综合利用问题，将会大大提高矿床的经济价值。     

Modeling of in-situ crystallization processes in the Permian mafic layered intrusion of Mont Collon (Dent Blanche nappe, western Alps)

The Mont Collon mafic complex is one of the best preserved examples of the Early Permian magmatism in the Central Alps, related to the intra-continental collapse of the Variscan belt. It mostly consists (> 95 vol.%) of ol + hy-normative plagioclase-wehrlites, olivine- and cpx-gabbros with cumulitic structures, crosscut by acid dikes. Pegmatitic gabbros, troctolites and anorthosites outcrop locally. A well-preserved cumulative sequence is exposed in the Dents de Bertol area (center of intrusion). P–T calculations indicate that this layered magma chamber emplaced at mid-crustal levels at about 0.5 GPa and 1100 °C. The Mont Collon cumulitic rocks record little magmatic differentiation, as illustrated by the restricted range of clinopyroxene mg-number (Mg#_cpx = 83–89). Whole-rock incompatible trace-element contents (e.g. Nb, Zr, Ba) vary largely and without correlation with major-element composition. These features are characteristic of an in-situ crystallization process with variable amounts of interstitial liquid L trapped between the cumulus mineral phases. LA-ICPMS measurements show that trace-element distribution in the latter is homogeneous, pointing to subsolidus re-equilibration between crystals and interstitial melts. A quantitative modeling based on Langmuir's in-situ crystallization equation successfully duplicated the REE concentrations in cumulitic minerals of all rock facies of the intrusion. The calculated amounts of interstitial liquid L vary between 0 and 35% for degrees of differentiation F of 0 to 20%, relative to the least evolved facies of the intrusion. L values are well correlated with the modal proportions of interstitial amphibole and whole-rock incompatible trace-element concentrations (e.g. Zr, Nb) of the tested samples. However, the in-situ crystallization model reaches its limitations with rock containing high modal content of REE-bearing minerals (i.e. zircon), such as pegmatitic gabbros. Dikes of anorthositic composition, locally crosscutting the layered lithologies, evidence that the Mont Collon rocks evolved in open system with mixing of intercumulus liquids of different origins and possibly contrasting compositions. The proposed model is not able to resolve these complex open systems, but migrating liquids could be partly responsible for the observed dispersion of points in some correlation diagrams. Absence of significant differentiation with recurrent lithologies in the cumulitic pile of Dents de Bertol points to an efficiently convective magma chamber, with possible periodic replenishment.     

Research of in-situ hydraulic test method by using double packer equipment

Double packer equipment for hydraulic test can be used to measure pressure of test zone directly, and it is frequently used to perform many kinds of hydraulic tests and take groundwater sample from borehole. The test method of this equipment mainly includes the test design, implementation, interpretation and synthetic analysis. By adopting the double packer equipment for hydraulic test, the parameter distribution of rock permeability along borehole can be acquired, as well as the connectivity, water conductivity and water bearing capacity of the disclosed structure and the chemical characteristics of the deep groundwater. It is a necessary method for the research and evaluation of the complex hypotonicity terrace site selection under geological conditions. This method is not only suitable for the geological disposal of high level radioactive waste, but also can be used in the site selection of underground facilities such as storage of petroleum and carbon dioxide. Meanwhile, it has a good application prospect in other hydrogeological investigation fields.     

Seismicity and fault aseismic deformation caused by fluid injection in decametric in-situ experiments

Seismicity induced by fluid perturbations became an important societal concern since felt earthquakes (M_w up to 6) occurred after anthropogenic activities. In order to mitigate the risks associated with undesired seismicity, as well as to be able to use the micro-seismicity as a probe for in-depth investigation of fluid-driven processes, it is of crucial importance to understand the links between seismicity, fluid pressure and flow. We have developed a series of in-situ, decameter-scale experiments of fault zone reactivation by controlled fluid injection, in order to improve the near-source geophysical and hydromechanical observations. The deployed geophysical monitoring close to the injection allows one to cover the full frequency range of the fault responses from the static deformation to the very high-frequency seismic emissions (up to 4 kHz). Here, we focus on the microseismicity (M_w ∼ –4 to –3) recorded during two fluid injection experiments in low-permeable shale and highly-fractured limestone formations. In both experiments, the spatio-temporal distribution of the seismic events, the energy balance, and the seismic velocity changes of the fractured medium show that most of the deformation does not actually emit seismic signals. The induced deformation is mainly aseismic. Based on these high-resolution multiparametric observations in the near-field, we therefore proposed a new model for injection-induced seismicity: the seismicity is not directly induced by the increasing fluid pressure, but it is rather triggered by the stress perturbations transferred from the aseismic motion caused by the injection.     

Advances and Trends in Atmospheric Measurement by Smartphones*

With the development and popularization of smartphones and embedded sensors, a non-professional atmospheric measurement method by using smartphones carried by the public has been proposed recently. Without extra dedicated instrument, this method has many advantages, such as low hardware cost, high spatio-temporal resolution, and wide coverage, and it can supplement the professional atmospheric measurement methods, which has broad applications in the meteorological operation, scientific research, public service, and other fields. At present, the research on the non-professional atmospheric measurement in China is limited. In order to make full use of this method, this paper briefly outlined the states of existing smartphones and embedded sensors, highlighted the measurement of precipitation, air temperature, pressure, aerosols, and radiation by smartphones. To promote the development of smartphones for atmospheric measurement, future research should focus on mechanism study, available sources exploration, data quality control, big data processing, joining and matching with operation, research and service, etc.     

中国卫星海洋观测系统及其传感器(1988—2025)

全面收集1988—2025年中国地球观测卫星(和飞船)计划,包括历史的、运行中的和列入未来计划的。详细介绍风云卫星系列(FY-n)、海洋卫星系列(HY-n)、资源卫星系列(ZY-n)、环境卫星系列(HJ-n)、中国遥感卫星系列(CRS-n)、灾害监测星座/北京小卫星(DMC/BJ-1)、神舟飞船系列(SZ-n)和天宫空间站系列(TG-n)等8个卫星(和飞船、空间站)系列。这些卫星(和飞船、空间站)系列都提供对海洋的观测,从而构成中国卫星海洋观测系统。按装载的传感器分类,进而给出中国的海色、海表温度、海面高度、海面风场和合成孔径雷达(SAR)卫星观测系统。对中国海洋观测卫星与国际海洋观测卫星装载的传感器性能作了比较和讨论,指出差距。列出目前在轨运行的中国海洋卫星观测系统38个传感器及其类似的国外卫星传感器。     

Research Status and Progress of Balloon-borne Cloud and Precipitation Particles Probe

The accurate observation of the microphysical structure of cloud and precipitation plays an important role in understanding the formation of clouds and precipitation. In-situ measurement using measuring instruments carried by meteorological balloons is an effective way to obtain the microphysical properties of cloud and precipitation particles, which is a supplementary means for aircraft to observe cloud and precipitation particles. This observation method plays a more and more important role in in-situ measurement. According to the difference of the working principle of the existing balloon-borne cloud and precipitation particles probes, the detectors can be divided into particle impact-sampling sensors, particle imaging sensors, light-scattering sensors, light intensity attenuation sensors and charge measurement sensors. The working principles, key technologies and main advantages and disadvantages of typical instruments were summarized, and their applications to detailed cloud structure acquisition, cloud remote sensing method establishment, cloud and precipitation physical process research and parameterization, and scientific observation of thunderstorm clouds were briefly introduced. Finally, the development trend of balloon-borne cloud precipitation particle detectors was prospected, which will provide reference for related technical research and equipment development.