Volume change of oil between reservoir condition and standard surface condition is called oil formation volume factor (FVF), which is very time, cost and labor intensive to determine. This study proposes an accurate, rapid and cost-effective approach for determining FVF from reservoir temperature, dissolved gas oil ratio, and specific gravity of both oil and dissolved gas. Firstly, structural risk minimization (SRM) principle of support vector regression (SVR) was employed to construct a robust model for estimating FVF from the aforementioned inputs. Subsequently, an alternating conditional expectation (ACE) was used for approximating optimal transformations of input/output data to a higher correlated data and consequently developing a sophisticated model between transformed data. Eventually, a committee machine with SVR and ACE was constructed through the use of hybrid genetic algorithm-pattern search (GA-PS). Committee machine integrates ACE and SVR models in an optimal linear combination such that makes benefit of both methods. A group of 342 data points was used for model development and a group of 219 data points was used for blind testing the constructed model. Results indicated that the committee machine performed better than individual models.
{"title":"Oil Formation Volume Factor Determination Through a Fused Intelligence","authors":"A. Gholami","doi":"10.1515/acgeo-2016-0099","DOIUrl":"https://doi.org/10.1515/acgeo-2016-0099","url":null,"abstract":"Volume change of oil between reservoir condition and standard surface condition is called oil formation volume factor (FVF), which is very time, cost and labor intensive to determine. This study proposes an accurate, rapid and cost-effective approach for determining FVF from reservoir temperature, dissolved gas oil ratio, and specific gravity of both oil and dissolved gas. Firstly, structural risk minimization (SRM) principle of support vector regression (SVR) was employed to construct a robust model for estimating FVF from the aforementioned inputs. Subsequently, an alternating conditional expectation (ACE) was used for approximating optimal transformations of input/output data to a higher correlated data and consequently developing a sophisticated model between transformed data. Eventually, a committee machine with SVR and ACE was constructed through the use of hybrid genetic algorithm-pattern search (GA-PS). Committee machine integrates ACE and SVR models in an optimal linear combination such that makes benefit of both methods. A group of 342 data points was used for model development and a group of 219 data points was used for blind testing the constructed model. Results indicated that the committee machine performed better than individual models.","PeriodicalId":50898,"journal":{"name":"Acta Geophysica","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2016-12-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1515/acgeo-2016-0099","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67091769","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Qiang Sun, Weiqiang Zhang, Yuliang Zhang, Lining Yang
This paper reports the variations of strength, resistivity and thermal parameters of clay after high-temperature heating. Experiments were carried out to test the physical properties of clay heated at temperatures ranging from room temperature to 800°C in a furnace. The experiment results show that below 400°C the uniaxial compressive strength and resistivity change very little. However, above 400°C, both increase rapidly. At a temperature under 400°C, the thermal conductivity and specific heat capacity decrease significantly. The thermogravimetric analysis (TG) and differential scanning calorimeter (DSC) test indicate that a series of changes occur in kaolinite at temperatures from 400 to 600°C, which is considered the primary cause of the variation of physical and mechanical properties of clay under high temperatures.
{"title":"Variations of Strength, Resistivity and Thermal Parameters of Clay after High Temperature Treatment","authors":"Qiang Sun, Weiqiang Zhang, Yuliang Zhang, Lining Yang","doi":"10.1515/acgeo-2016-0090","DOIUrl":"https://doi.org/10.1515/acgeo-2016-0090","url":null,"abstract":"This paper reports the variations of strength, resistivity and thermal parameters of clay after high-temperature heating. Experiments were carried out to test the physical properties of clay heated at temperatures ranging from room temperature to 800°C in a furnace. The experiment results show that below 400°C the uniaxial compressive strength and resistivity change very little. However, above 400°C, both increase rapidly. At a temperature under 400°C, the thermal conductivity and specific heat capacity decrease significantly. The thermogravimetric analysis (TG) and differential scanning calorimeter (DSC) test indicate that a series of changes occur in kaolinite at temperatures from 400 to 600°C, which is considered the primary cause of the variation of physical and mechanical properties of clay under high temperatures.","PeriodicalId":50898,"journal":{"name":"Acta Geophysica","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2016-12-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1515/acgeo-2016-0090","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67091834","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
We made an attempt to assess the shear wave velocity values VS and, to a lesser extent, the VP values from ambient noise recordings in an array configuration. Five array sites were situated in the close proximity to borehole sites. Shear wave velocity profiles were modeled at these five array sites with the aid of two computational techniques, viz. spatial autocorrelation (SPAC) and H/V ellipticity. Out of these five array sites, velocity estimates could be reliably inferred at three locations. The shear wave velocities estimated by these methods are found to be quite consistent with each other. The computed VS values up to 30 m depth are in the range from 275 to 375 m/s in most of the sites, which implies prevalence of a low velocity zone at some pocket areas. The results were corroborated by evidence of site geology as well as geotechnical information.
{"title":"Shear Wave Velocity Estimates through Combined Use of Passive Techniques in a Tectonically Active Area","authors":"R. Biswas, S. Baruah","doi":"10.1515/acgeo-2016-0086","DOIUrl":"https://doi.org/10.1515/acgeo-2016-0086","url":null,"abstract":"We made an attempt to assess the shear wave velocity values VS and, to a lesser extent, the VP values from ambient noise recordings in an array configuration. Five array sites were situated in the close proximity to borehole sites. Shear wave velocity profiles were modeled at these five array sites with the aid of two computational techniques, viz. spatial autocorrelation (SPAC) and H/V ellipticity. Out of these five array sites, velocity estimates could be reliably inferred at three locations. The shear wave velocities estimated by these methods are found to be quite consistent with each other. The computed VS values up to 30 m depth are in the range from 275 to 375 m/s in most of the sites, which implies prevalence of a low velocity zone at some pocket areas. The results were corroborated by evidence of site geology as well as geotechnical information.","PeriodicalId":50898,"journal":{"name":"Acta Geophysica","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2016-12-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1515/acgeo-2016-0086","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67091353","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The relationship between stratospheric QBO and the difference (ΔNmF2) between NmF2 calculated with IRI-2012 and measured from ionosondes at the Singapore and Ascension stations in the equatorial region was statistically investigated. As statistical analysis, the regression analysis was used on variables. As a result, the relationship between QBO and ΔNmF2 was higher for 24:00 LT (local time) than 12:00 LT. This relationship is positive in the solar maximum epoch for both stations. In the solar minimum epoch, it is negative at 24:00 LT for Ascension and at 12:00 LT for Singapore. Furthermore, it was seen that the relationship of the ΔNmF2 with both the easterly and westerly QBO was negative for all solar epochs and every LT, at Ascension station. This relationship was only positive for solar maximum epoch and 12:00 LT, at Singapore station.
{"title":"The Relationship of Stratospheric QBO with the Difference of Measured and Calculated NmF2","authors":"K. Kurt, A. Yesil, S. Sağır, R. Atıcı","doi":"10.1515/acgeo-2016-0061","DOIUrl":"https://doi.org/10.1515/acgeo-2016-0061","url":null,"abstract":"The relationship between stratospheric QBO and the difference (ΔNmF2) between NmF2 calculated with IRI-2012 and measured from ionosondes at the Singapore and Ascension stations in the equatorial region was statistically investigated. As statistical analysis, the regression analysis was used on variables. As a result, the relationship between QBO and ΔNmF2 was higher for 24:00 LT (local time) than 12:00 LT. This relationship is positive in the solar maximum epoch for both stations. In the solar minimum epoch, it is negative at 24:00 LT for Ascension and at 12:00 LT for Singapore. Furthermore, it was seen that the relationship of the ΔNmF2 with both the easterly and westerly QBO was negative for all solar epochs and every LT, at Ascension station. This relationship was only positive for solar maximum epoch and 12:00 LT, at Singapore station.","PeriodicalId":50898,"journal":{"name":"Acta Geophysica","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2016-12-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1515/acgeo-2016-0061","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67090171","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Paulina Szymańska, Witold Tisler, C. Schütz, A. Szymkiewicz, I. Neuweiler, R. Helmig
The paper presents a 2D upward infiltration experiment performed on a model porous medium consisting of fine sand background with two inclusions made of coarser sands. The purpose of the experiment was to investigate the effects of structural air trapping, which occurs during infiltration as a result of heterogeneous material structure. The experiment shows that a significant amount of air becomes trapped in each of the inclusions. Numerical simulations were carried out using the two-phase water-air flow model and the Richards equation. The experimental results can be reproduced with good accuracy only using a two-phase flow model, which accounts for both structural and pore-scale trapping. On the other hand, the Richards equation was not able to represent the structural trapping caused by material heterogeneity.
{"title":"Experimental and Numerical Analysis of Air Trapping in a Porous Medium with Coarse Textured Inclusions","authors":"Paulina Szymańska, Witold Tisler, C. Schütz, A. Szymkiewicz, I. Neuweiler, R. Helmig","doi":"10.1515/acgeo-2016-0095","DOIUrl":"https://doi.org/10.1515/acgeo-2016-0095","url":null,"abstract":"The paper presents a 2D upward infiltration experiment performed on a model porous medium consisting of fine sand background with two inclusions made of coarser sands. The purpose of the experiment was to investigate the effects of structural air trapping, which occurs during infiltration as a result of heterogeneous material structure. The experiment shows that a significant amount of air becomes trapped in each of the inclusions. Numerical simulations were carried out using the two-phase water-air flow model and the Richards equation. The experimental results can be reproduced with good accuracy only using a two-phase flow model, which accounts for both structural and pore-scale trapping. On the other hand, the Richards equation was not able to represent the structural trapping caused by material heterogeneity.","PeriodicalId":50898,"journal":{"name":"Acta Geophysica","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2016-12-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1515/acgeo-2016-0095","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67091708","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Mutual relationships between geological and geophysical data obtained by using methods of different scale are presented for the Miocene sandy-shaly thin-bedded formation and for the Zechstein carbonate formation. The common basis of laboratory results, well logging and seismic data was a recognition of elastic and reservoir properties of rocks. The common basis of laboratory results, well logging and seismic data were elastic and reservoir properties of rocks. Seismic attributes calculated from acoustic full waveforms were a link between the considered data. Seismic attributes strongly depend on small changes observed in rock formation related to lithology variations, facies changes, structural events and petrophysical properties variability. The observed trends and relationships of high correlation coefficients in the analysed data proved the assumption made at the beginning of research that common physical basis is a platform for data scaling. Proper scaling enables expanding the relationships determined from laboratory and well logging of petrophysical parameters to a seismic scale.
{"title":"Acoustic Full Waveforms as a Bridge between Seismic Data and Laboratory Results in Petrophysical Interpretation","authors":"K. Wawrzyniak-Guz","doi":"10.1515/acgeo-2016-0116","DOIUrl":"https://doi.org/10.1515/acgeo-2016-0116","url":null,"abstract":"Mutual relationships between geological and geophysical data obtained by using methods of different scale are presented for the Miocene sandy-shaly thin-bedded formation and for the Zechstein carbonate formation. The common basis of laboratory results, well logging and seismic data was a recognition of elastic and reservoir properties of rocks. The common basis of laboratory results, well logging and seismic data were elastic and reservoir properties of rocks. Seismic attributes calculated from acoustic full waveforms were a link between the considered data. Seismic attributes strongly depend on small changes observed in rock formation related to lithology variations, facies changes, structural events and petrophysical properties variability. The observed trends and relationships of high correlation coefficients in the analysed data proved the assumption made at the beginning of research that common physical basis is a platform for data scaling. Proper scaling enables expanding the relationships determined from laboratory and well logging of petrophysical parameters to a seismic scale.","PeriodicalId":50898,"journal":{"name":"Acta Geophysica","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2016-12-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1515/acgeo-2016-0116","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67092927","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A new method is introduced to determine the top and bottom depth of a vertical line using gravity anomalies. For this, gravity at a distance x from the origin and horizontal derivative at that point are utilized. A numerical value is obtained dividing the gravity at point x by horizontal derivative. Then a new equation is obtained dividing the theoretical gravity equation by the derivative equation. In that equation, assigning various values to the depth and length of vertical line, several new numerical values are obtained. Among these values, a curve is obtained for the one that is closest to the first value from attending the depth and length values. The intersection point of these curves obtained by repeating this procedure several times for different points x yield the real depth and length values of the line. The method is tested on two synthetics and field examples. Successful results are obtained in both applications.
{"title":"An Easy Method for Interpretation of Gravity Anomalies Due to Vertical Finite Lines","authors":"I. Kara, N. Hoskan","doi":"10.1515/acgeo-2016-0097","DOIUrl":"https://doi.org/10.1515/acgeo-2016-0097","url":null,"abstract":"A new method is introduced to determine the top and bottom depth of a vertical line using gravity anomalies. For this, gravity at a distance x from the origin and horizontal derivative at that point are utilized. A numerical value is obtained dividing the gravity at point x by horizontal derivative. Then a new equation is obtained dividing the theoretical gravity equation by the derivative equation. In that equation, assigning various values to the depth and length of vertical line, several new numerical values are obtained. Among these values, a curve is obtained for the one that is closest to the first value from attending the depth and length values. The intersection point of these curves obtained by repeating this procedure several times for different points x yield the real depth and length values of the line. The method is tested on two synthetics and field examples. Successful results are obtained in both applications.","PeriodicalId":50898,"journal":{"name":"Acta Geophysica","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2016-12-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1515/acgeo-2016-0097","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67091754","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In 2011, a geophysical survey was carried out in the surroundings of the Jagiellonian University in Cracow, using a Very Low Frequency method. The measurements were designed to determine the reason of frequent flooding of the lowest level of the building. The main objective of the study was to find out from where and in which way the rainwater seeps into the building and how this problem can be solved in the least invasive manner. The aim of geophysical methods was also to provide necessary information that will enable the construction of a hydro-geological model of the local environment. The interpretation revealed the presence of a sandy gutter surrounded by impermeable clay. There is a big resistivity contrast between those layers. Their location and approximate dimensions were determined.
{"title":"Very Low Frequency Electromagnetic Induction Surveys in Hydrogeological Investigations; Case Study from Poland","authors":"S. Oryński, M. Okoń, W. Klityński","doi":"10.1515/acgeo-2016-0092","DOIUrl":"https://doi.org/10.1515/acgeo-2016-0092","url":null,"abstract":"In 2011, a geophysical survey was carried out in the surroundings of the Jagiellonian University in Cracow, using a Very Low Frequency method. The measurements were designed to determine the reason of frequent flooding of the lowest level of the building. The main objective of the study was to find out from where and in which way the rainwater seeps into the building and how this problem can be solved in the least invasive manner. The aim of geophysical methods was also to provide necessary information that will enable the construction of a hydro-geological model of the local environment. The interpretation revealed the presence of a sandy gutter surrounded by impermeable clay. There is a big resistivity contrast between those layers. Their location and approximate dimensions were determined.","PeriodicalId":50898,"journal":{"name":"Acta Geophysica","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2016-12-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1515/acgeo-2016-0092","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67092019","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This paper presents a study of the nonlinear estimation of the ground motion prediction equation (GMPE) using neural networks. The general regression neural network (GRNN) was chosen for its high learning rate. A separate GRNN was tested as well as a GRNN in cascade connection with linear regression (LR). Measurements of induced seis-micity in the Legnica-Głogów Copper District were used in this study. Various sets of input variables were tested. The basic variables used in every case were seismic energy and epicentral distance, while the additional variables were the location of the epicenter, the location of the seismic station, and the direction towards the epicenter. The GRNN improves the GMPE. The best results were obtained when the epicenter location was used as an additional input. The GRNN model was analysed for how it can improve the GMPE with respect to LR. The bootstrap resampling method was used for this purpose. It proved the statistical significance of the improvement of the GMPE. Additionally, this method allows the determination of smoothness parameters for the GRNN. Parameters derived through this method have better generalisation capabilities than the smoothness parameters estimated using the holdout method.
{"title":"Applying the General Regression Neural Network to Ground Motion Prediction Equations of Induced Events in the Legnica-Głogów Copper District in Poland","authors":"J. Wiszniowski","doi":"10.1515/acgeo-2016-0104","DOIUrl":"https://doi.org/10.1515/acgeo-2016-0104","url":null,"abstract":"This paper presents a study of the nonlinear estimation of the ground motion prediction equation (GMPE) using neural networks. The general regression neural network (GRNN) was chosen for its high learning rate. A separate GRNN was tested as well as a GRNN in cascade connection with linear regression (LR). Measurements of induced seis-micity in the Legnica-Głogów Copper District were used in this study. Various sets of input variables were tested. The basic variables used in every case were seismic energy and epicentral distance, while the additional variables were the location of the epicenter, the location of the seismic station, and the direction towards the epicenter. The GRNN improves the GMPE. The best results were obtained when the epicenter location was used as an additional input. The GRNN model was analysed for how it can improve the GMPE with respect to LR. The bootstrap resampling method was used for this purpose. It proved the statistical significance of the improvement of the GMPE. Additionally, this method allows the determination of smoothness parameters for the GRNN. Parameters derived through this method have better generalisation capabilities than the smoothness parameters estimated using the holdout method.","PeriodicalId":50898,"journal":{"name":"Acta Geophysica","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2016-12-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1515/acgeo-2016-0104","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67092204","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
E. Gunawan, P. Maulida, I. Meilano, M. Irsyam, J. Efendi
Based on continuous GPS data, we analyze coseismic deformation due to the 2012 Indian Ocean earthquake. We use the available coseismic slip models of the 2012 earthquake, derived from geodetic and/or seismic waveform inversion, to calculate the coseismic displacements in the Andaman-Nicobar, Sumatra and Java. In our analysis, we employ a spherical, layered model of the Earth and we find that Java Island experienced coseismic displacements up to 8 mm, as also observed by our GPS network. Compared to coseismic offsets measured from GPS data, a coseismic slip model derived from multiple observations produced better results than a model based on a single type of observation.
{"title":"Analysis of Coseismic Fault Slip Models of the 2012 Indian Ocean Earthquake: Importance of GPS Data for Crustal Deformation Studies","authors":"E. Gunawan, P. Maulida, I. Meilano, M. Irsyam, J. Efendi","doi":"10.1515/acgeo-2016-0106","DOIUrl":"https://doi.org/10.1515/acgeo-2016-0106","url":null,"abstract":"Based on continuous GPS data, we analyze coseismic deformation due to the 2012 Indian Ocean earthquake. We use the available coseismic slip models of the 2012 earthquake, derived from geodetic and/or seismic waveform inversion, to calculate the coseismic displacements in the Andaman-Nicobar, Sumatra and Java. In our analysis, we employ a spherical, layered model of the Earth and we find that Java Island experienced coseismic displacements up to 8 mm, as also observed by our GPS network. Compared to coseismic offsets measured from GPS data, a coseismic slip model derived from multiple observations produced better results than a model based on a single type of observation.","PeriodicalId":50898,"journal":{"name":"Acta Geophysica","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2016-12-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1515/acgeo-2016-0106","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67092484","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}