In order to obtain stable interval Q factor, by analyzing the spectrum of monitoring wavelet and down-going wavelet of zero-offset VSP data and referring the spectrum expression of Ricker wavelet, we propose a new exp...In order to obtain stable interval Q factor, by analyzing the spectrum of monitoring wavelet and down-going wavelet of zero-offset VSP data and referring the spectrum expression of Ricker wavelet, we propose a new expression of source wavelet spectrum. Basing on the new expression, we present improved amplitude spectral fitting and spectral ratio methods for interval Q inversion based on zero-offset VSP data, and the sequence for processing the zero-offset VSP data. Subsequently, we apply the proposed methods to real zero-offset VSP data, and carry out prestack inverse Q filtering to zero-offset VSP data and surface seismic data for amplitude compensation with the estimated Q value.展开更多
The traditional gravity modelling methods fail to deal with ambiguity zones. These zones are likely to be associated with uncertain boundaries. Source boundaries can be divided into "hard "and "soft &qu...The traditional gravity modelling methods fail to deal with ambiguity zones. These zones are likely to be associated with uncertain boundaries. Source boundaries can be divided into "hard "and "soft "types."Hard"boundary stands for distinguished margin of discontinuity of source distributions. Traditional modelling method is based on this type of boundary. Uncertain boundaries of ambiguity zones belong to "soft"boundary.The authors put forward the uncertainty analysis because lots of uncertainty factors need to be taken into consideration. Any powerful system designed to interpret gravity data for a real source distribution must be able to deal with uncertain information. Uncertainty analysis( UA) is a useful tool to estimate the ambiguity of the data interpretation. It is often applied in conjunction with a specific modelling or inversion method. In this study,we use an iterative inversion and its results are evaluated using uncertainty analysis and proved to be effective.展开更多
Based on the convection and diffusion mechanisms of radon migration, in this paper we deduce the two-dimensional differential equation for radon transportation in the overburden above active fault zones with an unlimi...Based on the convection and diffusion mechanisms of radon migration, in this paper we deduce the two-dimensional differential equation for radon transportation in the overburden above active fault zones with an unlimited extension along the strike. Making use of the finite difference method, the radon concentration distribution in the overburden above active faults is calculated and modeled. The active fault zone parameters, such as the depth and the width of the fault zone, and the value of radon concentration, can be inverted from the measured radon concentration curve. These realize quantitative interpretation for radon concentration anomalies. The inversion results are in good agreement with the actual fault zone parameters.展开更多
基金sponsored by the National Nature Science Foundation of China(Nos.41174114 and 41274128)
文摘In order to obtain stable interval Q factor, by analyzing the spectrum of monitoring wavelet and down-going wavelet of zero-offset VSP data and referring the spectrum expression of Ricker wavelet, we propose a new expression of source wavelet spectrum. Basing on the new expression, we present improved amplitude spectral fitting and spectral ratio methods for interval Q inversion based on zero-offset VSP data, and the sequence for processing the zero-offset VSP data. Subsequently, we apply the proposed methods to real zero-offset VSP data, and carry out prestack inverse Q filtering to zero-offset VSP data and surface seismic data for amplitude compensation with the estimated Q value.
基金Supported by projects of the National Key Research and Development Plan(Nos.2017YFC0602203,2017YFC0601606)the National Science and Technology Major Project Task(No.2016ZX05027-002-03)National Natural Science Foundation of China(Nos.41604098,41404089,41430322)
文摘The traditional gravity modelling methods fail to deal with ambiguity zones. These zones are likely to be associated with uncertain boundaries. Source boundaries can be divided into "hard "and "soft "types."Hard"boundary stands for distinguished margin of discontinuity of source distributions. Traditional modelling method is based on this type of boundary. Uncertain boundaries of ambiguity zones belong to "soft"boundary.The authors put forward the uncertainty analysis because lots of uncertainty factors need to be taken into consideration. Any powerful system designed to interpret gravity data for a real source distribution must be able to deal with uncertain information. Uncertainty analysis( UA) is a useful tool to estimate the ambiguity of the data interpretation. It is often applied in conjunction with a specific modelling or inversion method. In this study,we use an iterative inversion and its results are evaluated using uncertainty analysis and proved to be effective.
文摘Based on the convection and diffusion mechanisms of radon migration, in this paper we deduce the two-dimensional differential equation for radon transportation in the overburden above active fault zones with an unlimited extension along the strike. Making use of the finite difference method, the radon concentration distribution in the overburden above active faults is calculated and modeled. The active fault zone parameters, such as the depth and the width of the fault zone, and the value of radon concentration, can be inverted from the measured radon concentration curve. These realize quantitative interpretation for radon concentration anomalies. The inversion results are in good agreement with the actual fault zone parameters.
