Li S.,China University of Petroleum - East China |
Jiang X.,China University of Petroleum - East China |
Liu C.,Institute of Marine Geology
Petroleum Science and Technology | Year: 2012
A general-purpose simulator for gas production from hydrates is developed, which considers kinetics of dissociation, heat, and multiphase fluid flow. Production behavior of the Class I hydrate reservoir by depressurization technique is studied. The results suggest gas production rate at the well is higher than gas release rate in the reservoir and most water released is left in pores. With continuous dissociation of hydrate, average hydrate saturation, reservoir temperature, and pressure decrease continuously. In addition, the closer to gas layer, the faster the hydrate dissociation. Results of gas production simulations can provide theoretical basis for the development of hydrates in the future. © 2012 Copyright Taylor and Francis Group, LLC.
Liu Z.,Soochow University of China |
Pan S.,Nanjing University |
Sun Z.,Nanjing University |
Sun Z.,Institute of Marine Geology |
And 4 more authors.
Marine Pollution Bulletin | Year: 2015
This research focuses on the spatial and temporal patterns of heavy metals from the Yangtze River estuary and the tidal flat of north Jiangsu. Most heavy metals in the surficial sediments after normalization to Ti decreased seaward at the Yangtze River estuary. The core records showed that the heavy metal variations in the last 50. years were primarily linked to natural weathering input of trace elements. However, significant heavy metal pollution (mainly Ni, Pb, Cd, Cu and As) were in the two study areas, with anthropogenic inventories accounting for 23-40% percent of the total pollution. Sequential extraction showed that Pb, Cu and Ni were present largely in the non-residual fraction, which indicated the potential bioavailability in the study areas. The SEM/EDS together with sequential extraction facilitated the easy tracing of the origin/sources of heavy metals in a simple way in the estuary and the tidal flat. © 2015 Elsevier Ltd.
Nie P.,Institute of Marine Geology |
Zhang L.,Jilin University |
Li Y.,Jilin University |
Yang B.,Jilin University |
Luan X.,Institute of Marine Geology
IEEE Transactions on Geoscience and Remote Sensing | Year: 2014
We address the directional derivative trace transform (DDTT) for seismic wavefield separation. The goal is to separate the different seismic waves, which is a practical requirement for seismic exploration and geophysics. The DDTT is based on the trace transform, which is a generalization of the Radon transform (RT). It calculates the integral of a directional derivative along the trace line. The directional derivative is the pointwise rate of change of a function in a certain direction. Therefore, the DDTT better reflects the property of linear wavefields and other wavefields than the F-K filtering and RT methods. The DDTT domain consists of two parts: One part mostly represents linear wavefields such as surface waves, and the other part mostly represents the reflection signals. Based on this property, a parametric method is proposed for separating the ground roll better. In order to return data to the time-offset domain, we derive the inverse DDTT using the properties of the Fourier transform and the Hilbert transform. We show the potential of our method for the removal of ground roll on synthetic and real data examples. © 1980-2012 IEEE.
Wang J.,CAS Qingdao Institute of Oceanology |
Wang J.,University of Chinese Academy of Sciences |
Luan X.,Institute of Marine Geology |
Yu R.Z.,CAS Qingdao Institute of Oceanology
Chinese Journal of Oceanology and Limnology | Year: 2013
To better understand the crustal deformation of the South China Sea Basin, we produce a mechanically consistent 2-dimensional model for observing regional velocity field in the South China Sea (SCS). We studied the dominating regional tectonic stress field by geodetic measurements and finite element analysis, the spatial variations of velocity field and strain field, and relative movements among different blocks, using a 2-dimensional model describing crustal deformation of the South China Sea Basin. Strain results show that the SCS is extending at present. The western part of SCS is opening gradually in NWSE direction from its northern margin to the south, but the eastern part of SCS is opening gradually from its central part to the north and south. In addition, we analyzed the plate kinematics to the deformation of the SCS, using a two-dimensional finite element model. Our simulations results are well explained by available geodetic data. The movement of SCS is resulted from interactions among Indian Plate, Pacific Plate, Philippine Sea Plate, and Eurasian Plate. © 2013 Chinese Society for Oceanology and Limnology, Science Press and Springer-Verlag Berlin Heidelberg.
Shang L.,Ocean University of China |
Shang L.,Function Laboratory for Marine Mineral Resource Geology and Exploration |
Shang L.,Institute of Marine Geology |
Zhang X.,Function Laboratory for Marine Mineral Resource Geology and Exploration |
And 4 more authors.
Journal of Ocean University of China | Year: 2016
In this paper, two sets of gravity and magnetic data were used to study the tectonics of the southern East China Sea and Ryukyu trench-arc system: one data set was from the ‘Geological-geophysical map series of China Seas and adjacent areas’ database and the other was newly collected by R/V Kexue III in 2011. Magnetic and gravity data were reorganized and processed using the software MMDP, MGDP and RGIS. In addition to the description of the anomaly patterns in different areas, deep and shallow structure studies were performed by using several kinds of calculation, including a spectrum analysis, upward-continuation of the Bouguer anomaly and horizontal derivatives of the total-field magnetic anomaly. The depth of the Moho and magnetic basement were calculated. Based on the above work, several controversial tectonic problems were discussed. Compared to the shelf area and Ryukyu Arc, the Okinawa Trough has an obviously thinned crust, with the thinnest area having thickness less than 14 km in the southern part. The Taiwan-Sinzi belt, which terminates to the south by the NW-SE trending Miyako fault belt, contains the relic volcanic arc formed by the splitting of the paleo Ryukyu volcanic arc as a result of the opening of the Okinawa Trough. As an important tectonic boundary, the strike-slip type Miyako fault belt extends northwestward into the shelf area and consists of several discontinuous segments. A forearc terrace composed of an exotic terrane collided with the Ryukyu Arc following the subduction of the Philippine Sea Plate. Mesozoic strata of varying thicknesses exist beneath the Cenozoic strata in the shelf basin and significantly influence the magnetic pattern of this area. The gravity and magnetic data support the existence of a Great East China Sea, which suggests that the entire southern East China Sea shelf area was a basin in the Mesozoic without alternatively arranged uplifts and depressions, and might have extended southwestward and connected with the northern South China Sea shelf basin. © 2016, Science Press, Ocean University of China and Springer-Verlag Berlin Heidelberg.