arXiv: Geophysics最新文献_第7页

Fluid forces or impacts, what governs the entrainment of soil particles in sediment transport mediated by a Newtonian fluid? 流体力或冲击，是什么控制了由牛顿流体介导的泥沙运输中土壤颗粒的夹带?

arXiv: Geophysics Pub Date : 2016-05-24 DOI: 10.1103/PhysRevFluids.2.074303

Thomas Pahtz, O. Dur'an

引用次数: 45

Indo-Pacific variability on seasonal to multidecadal timescales. Part I: Intrinsic SST modes in models and observations 印度-太平洋在季节和多年代际时间尺度上的变化。第一部分:模式和观测中的内在海温模态

arXiv: Geophysics Pub Date : 2016-04-06 DOI: 10.1175/JCLI-D-16-0176.1

J. Slawinska, D. Giannakis

{"title":"Indo-Pacific variability on seasonal to multidecadal timescales. Part I: Intrinsic SST modes in models and observations","authors":"J. Slawinska, D. Giannakis","doi":"10.1175/JCLI-D-16-0176.1","DOIUrl":"https://doi.org/10.1175/JCLI-D-16-0176.1","url":null,"abstract":"The variability of Indo-Pacific SST on seasonal to multidecadal timescales is investigated using a recently introduced technique called nonlinear Laplacian spectral analysis (NLSA). Through this technique, drawbacks associated with ad hoc pre-filtering of the input data are avoided, enabling recovery of low-frequency and intermittent modes not previously accessible via classical approaches. Here, a multiscale hierarchy of spatiotemporal modes is identified for Indo-Pacific SST in millennial control runs of CCSM4 and CM3 and in HadISST data. On interannual timescales, a mode with spatiotemporal patterns corresponding to the fundamental component of ENSO emerges, along with ENSO-modulated annual modes consistent with combination mode theory. The ENSO combination modes also feature prominent activity in the Indian Ocean, explaining significant fraction of the SST variance in regions associated with the Indian Ocean dipole. A pattern resembling the tropospheric biennial oscillation emerges in addition to ENSO and the associated combination modes. On multidecadal timescales, the dominant NLSA mode in the model data is predominantly active in the western tropical Pacific. The interdecadal Pacific oscillation also emerges as a distinct NLSA mode, though with smaller explained variance than the western Pacific multidecadal mode. Analogous modes on interannual and decadal timescales are also identified in HadISST data for the industrial era, as well as in model data of comparable timespan, though decadal modes are either absent or of degraded quality in these datasets.","PeriodicalId":390991,"journal":{"name":"arXiv: Geophysics","volume":"204 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-04-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128306529","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 24

A novel workflow for seismic net pay estimation with uncertainty 一种新的不确定地震网产层估计工作流程

arXiv: Geophysics Pub Date : 2016-04-02 DOI: 10.1190/segam2016-13879729.1

M. Glinsky, D. Baptiste, Muhlis Unaldi, V. Nagassar

{"title":"A novel workflow for seismic net pay estimation with uncertainty","authors":"M. Glinsky, D. Baptiste, Muhlis Unaldi, V. Nagassar","doi":"10.1190/segam2016-13879729.1","DOIUrl":"https://doi.org/10.1190/segam2016-13879729.1","url":null,"abstract":"This paper presents a novel workflow for seismic net pay estimation with uncertainty. It is demonstrated on the Cassra/Iris Field. The theory for the stochastic wavelet derivation (which estimates the seismic noise level along with the wavelet, time-to-depth mapping, and their uncertainties), the stochastic sparse spike inversion, and the net pay estimation (using secant areas) along with its uncertainty; will be outlined. This includes benchmarking of this methodology on a synthetic model. A critical part of this process is the calibration of the secant areas. This is done in a two step process. First, a preliminary calibration is done with the stochastic reflection response modeling using rock physics relationships derived from the well logs. Second, a refinement is made to the calibration to account for the encountered net pay at the wells. Finally, a variogram structure is estimated from the extracted secant area map, then used to build in the lateral correlation to the ensemble of net pay maps while matching the well results to within the nugget of the variogram. These net pay maps are then integrated, over the area of full saturation gas, to give the GIIP distribution (Gaussian distributions for the porosity, gas expansion factor, and gas saturation for the sand end member are assumed and incorporated in the estimate of GIIP). The method is demonstrated on the Iris (UP5 turbidite) interval. The net pay is corrected for reduction in the amplitudes over part of the area due to shallow gas. The sensitivity of the GIIP to the independent stochastic variables is estimated (determining the value of information) so that business decisions can be made that maximize the value of the field.","PeriodicalId":390991,"journal":{"name":"arXiv: Geophysics","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125135197","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Decreasing groundwater quality at Cisadane riverbanks: groundwater-surface water approach 西沙达纳河岸地下水质量下降:地下水-地表水方法

arXiv: Geophysics Pub Date : 2016-03-20 DOI: 10.6084/M9.FIGSHARE.3119806.V1

Dasapta Erwin Irawan, D. J. Puradimaja, D. Yeni, A. A. Kuntoro, M. M. Julian

{"title":"Decreasing groundwater quality at Cisadane riverbanks: groundwater-surface water approach","authors":"Dasapta Erwin Irawan, D. J. Puradimaja, D. Yeni, A. A. Kuntoro, M. M. Julian","doi":"10.6084/M9.FIGSHARE.3119806.V1","DOIUrl":"https://doi.org/10.6084/M9.FIGSHARE.3119806.V1","url":null,"abstract":"The decreasing of groundwater quality has been the major issue in Tangerang area. One of the key process is the interaction between groundwater and Cisadane river water, which flows over volcanic deposits of Bojongmanik Fm, Genteng Fm, Tuf Banten, and Alluvial Fan. The objective of this study is to unravel such interactions based on the potentiometric mapping in the riverbank. We had 60 stop sites along the riverbank for groundwater and river water level observations, and chemical measurements (TDS, EC, temp, and pH). Three river water gauge were also analyzed to see the fluctuations. \u0000We identified three types of hydrodynamic relationships with fairly low flow gradients: effluent flow at Segmen I (Kranggan - Batuceper) with 0.2-0.25 gradient, perched flow at Segmen II (Batuceper-Kalibaru) with gradient 0.2-0.25, and influent flow at Segmen III (Kalibaru-Tanjungburung) with gradient 0.15-0.20. Such low flow gradient is controlled by the moderate to low morphological slope in the area. The gaining and losing stream model were also supported by the river water fluctuation data. TDS and EC readings increased more than 40$%$ from upstream to downstream. At some points the both measurements were two times higher than the permissible limits, along with the drops of pH values at those areas. \u0000This study shows the very close interaction between Cisadane river water and groundwater in the riverbank. Therefore the authorities need to be managed the areas with a very strict regulations related to the small and large scale industries located near by the river.","PeriodicalId":390991,"journal":{"name":"arXiv: Geophysics","volume":"66 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122273416","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 3

Optimal Transport for Seismic Full Waveform Inversion 地震全波形反演的最佳传输方法

arXiv: Geophysics Pub Date : 2016-02-04 DOI: 10.4310/CMS.2016.V14.N8.A9

Bjorn Engquist, Brittany D. Froese, Yunan Yang

引用次数: 120

Imminent Earthquake Forecasting on the Basis of Japan INTERMAGNET Stations, NEIC, NOAA and Tide Code Data Analysis 基于日本INTERMAGNET台站、NEIC、NOAA和潮汐码数据分析的临震预报

arXiv: Geophysics Pub Date : 2016-01-30 DOI: 10.4236/ojer.2016.51005.

S. Mavrodiev

{"title":"Imminent Earthquake Forecasting on the Basis of Japan INTERMAGNET Stations, NEIC, NOAA and Tide Code Data Analysis","authors":"S. Mavrodiev","doi":"10.4236/ojer.2016.51005.","DOIUrl":"https://doi.org/10.4236/ojer.2016.51005.","url":null,"abstract":"This research presents one possible way for imminent prediction of earthquakes’ magnitude, depth and epicenter coordinates by solving the inverse problem using a data acquisition network system for monitoring, archiving and complex analysis of geophysical variables-precursors. Among many possible precursors the most reliable are the geoelectromagnetic field, the boreholes water level, radon earth-surface concentration, the local heat flow, ionosphere variables, low frequency atmosphere and Earth core waves. The title demonstrates that only geomagnetic data are used in this study. Within the framework of geomagnetic quake approach it is possible to perform an imminent regional seismic activity forecasting on the basis of simple analysis of geomagnetic data which use a new variable SChtM with dimension surface density of energy. Such analysis of Japan Memambetsu, Kakioka, Kanoya INTERMAGNET stations and NEIC earthquakes data, the hypothesis that the “predicted” earthquake is this with biggest value of the variable SChtM permits to formulate an inverse problem (overdetermined algebraic system) for precursor’s signals like a function of earthquake’s magnitude, depth and distance from a monitoring point. Thus, in the case of data acquisition network system existence, which includes monitoring of more than one reliable precursor variables in at least four points distributed within the area with a radius of up to 700 km, there will be enough algebraic equations for calculation of impending earthquake’s magnitude, depth and distance, solving the overdetermined algebraic system.","PeriodicalId":390991,"journal":{"name":"arXiv: Geophysics","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-01-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132721647","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 4

A minimal coupled fluid-discrete element model for bedload transport 层质输运的最小耦合流体-离散元模型

arXiv: Geophysics Pub Date : 2015-11-19 DOI: 10.1063/1.4935703

R. Maurin, J. Chauchat, B. Chareyre, P. Frey

{"title":"A minimal coupled fluid-discrete element model for bedload transport","authors":"R. Maurin, J. Chauchat, B. Chareyre, P. Frey","doi":"10.1063/1.4935703","DOIUrl":"https://doi.org/10.1063/1.4935703","url":null,"abstract":"A minimal Lagragian two-phase model to study turbulent bedload transport focusing on the granular phase is presented, and validated with experiments. The model intends to describe bedload transport of massive particles in fully rough flows at relatively low Shields numbers, for which no suspension occurs. A discrete element method for the granular phase is coupled with a one dimensional volume-averaged two-phase momentum equation for the fluid phase. The coupling between the discrete granular phase and the continuous fluid phase is discussed, and a consistent averaging formulation adapted to bedload transport is introduced. An original simple discrete random walk model is proposed to account for the fluid velocity fluctuations. The model is compared with experiments considering both classical sediment transport rate as a function of the Shields number, and depth profiles of solid velocity, volume fraction, and transport rate density, from existing bedload transport experiments in inclined flume. The results successfully reproduce the classical 3/2 power law, and more importantly describe well the depth profiles of the granular phase, showing that the model is able to reproduce the particle scale mechanisms. From a sensitivity analysis, it is shown that the fluctuation model allows to reproduce a realistic critical Shields number, and that the influence of the granular parameters on the macroscopic results are weak. Nevertheless, the analysis of the corresponding depth profiles reveals an evolution of the depth structure of the granular phase with varying restitution and friction coefficients, which denotes the non-trivial underlying physical mechanisms.","PeriodicalId":390991,"journal":{"name":"arXiv: Geophysics","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-11-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124225888","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 64

Lithosphere-asthenosphere system in the Mediterranean region in the framework of polarized plate tectonics 极化板块构造框架下地中海地区岩石圈-软流圈系统

arXiv: Geophysics Pub Date : 2015-10-05 DOI: 10.3997/2214-4609.201414203

R. Raykova, G. Panza, C. Doglioni

引用次数: 1

Long term continuous radon monitoring in a seismically active area 地震活动区氡的长期连续监测

arXiv: Geophysics Pub Date : 2015-10-02 DOI: 10.4401/ag-6735

A. Piersanti, V. Cannelli, G. Galli

引用次数: 17

Methane storage in nanoporous media as observed via high field NMR relaxometry 利用高场核磁共振弛豫仪观察纳米多孔介质中的甲烷储存

arXiv: Geophysics Pub Date : 2015-07-24 DOI: 10.1103/PhysRevApplied.4.024018

A. Papaioannou, Ravinath Kausik

{"title":"Methane storage in nanoporous media as observed via high field NMR relaxometry","authors":"A. Papaioannou, Ravinath Kausik","doi":"10.1103/PhysRevApplied.4.024018","DOIUrl":"https://doi.org/10.1103/PhysRevApplied.4.024018","url":null,"abstract":"The storage properties of methane gas in Vycor porous glass (5.7 nm) are characterized in a wide pressure range from 0.7 MPa-89.7 MPa using Nuclear Magnetic Resonance (NMR). We demonstrate the capability of high field NMR relaxometry for the determination of the methane gas storage capacity and the measurement of the Hydrogen Index, to a high degree of accuracy. This helps determine the excess gas in the pore space which can be identified to exhibit Langmuir properties in the low pressure regime of 0.7 MPa to 39.6 Mpa. The Langmuir model enables us to determine the equilibrium density of the monolayer of adsorbed gas to be 8.5% lower than that of liquid methane. We also identify the signatures of multilayer adsorption at the high pressure regime from 39.6 Mpa to 89.7 Mpa and use the Brunauer-Emmet-Teller (BET) theory to determine the number of adsorbed layers of methane gas. We show how these measurements help us differentiate the gas stored in the Vycor pore space into free and adsorbed fractions for the entire pressure range paving way for similar applications such as studying natural gas storage in gas shale rock or hydrogen storage in carbon nanotubes.","PeriodicalId":390991,"journal":{"name":"arXiv: Geophysics","volume":"194 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122518257","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 23