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Located in the Sichuan Basin, site of one of China’s premier shale plays, Chengdu University of Technology, in collaboration with Southwest Petroleum University, and State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation, and sponsorship from Geological Society of China and the Chinese Petroleum Society, brought together geoscientists and engineers from around the world and the country for the 7th International Symposium on Unconventional Petroleum Exploration and Exploitation.
Added on 06 August, 2014
We present a method of using fault displacement-distance profiles to distinguish fault-bend, shear fault-bend, and fault-propagation folds, and use these insights to guide balanced and retrodeformable interpretations of these structures. We first describe the displacement profiles associated with different end-member fault-related folding models, then provide examples of structures that are consistent with these model-based predictions. Natural examples are imaged in high-resolution two- and three dimensional seismic reflection data sets from the Niger Delta, Sichuan Basin, Sierras Pampeanas, and Cascadia to record variations in displacement with distance updip along faults (termed displacement-distance profiles). Fault-bend folds exhibit constant displacement along fault segments and changes in displacement associated with bends in faults, shear fault-bend folds demonstrate an increase in displacement through the shearing interval, and fault-propagation folds exhibit decreasing displacement toward the fault tip. More complex structures are then investigated using this method, demonstrating that displacement-distance profiles can be used to provide insight into structures that involve multiple fault-related folding processes or have changed kinematic behavior over time. These interpretations are supported by comparison with the kinematics inferred from the geometry of growth strata overlying these structures. Collectively, these analyses illustrate that the displacement-distance approach can provide valuable insights into the styles of fault-related folding.
Added on 31 January, 2014
The Tarim Basin is one of the most important hydrocabon-bearing evaporite basins in China. Four salt-bearing sequences, the Middle and Lower Cambrian, the Mississippian, the Paleogene, and the Neogene, have various thickness and areal distribution. They are important detachment layers and intensely affect the structural deformation in the basin. The Kuqa depression is a subordinate structural unit with abundant salt structures in the Tarim Basin. Salt overthrusts, salt pillows, salt anticlines, salt diapirs, and salt-withdrawal basins are predominant in the depression. Contraction that resulted from orogeny played a key function on the formation of salt structures. Growth strata reveal that intense salt structural deformation in the Kuqa depression occurred during the Himalayan movement from Oligocene to Holocene, with early structural deformation in the north and late deformation in the south. Growth sequences also record at least two phases of salt tectonism. In the Yingmaili, Tahe, and Tazhong areas, low-amplitude salt pillows are the most common salt structures, and these structures are commonly accompanied by thrust faults. The faulting and uplifting of basement blocks controlled the location of salt structures. The differences in the geometries of salt structures in different regions show that the thickness of the salt sequences has an important influence on the development of salt-cored detachment folds and related thrust faults in the Tarim Basin.
Salt sequences and salt structures in the Tarim Basin are closely linked to hydrocarbon accumulations. Oil and gas fields have been discovered in the subsalt, intrasalt, and suprasalt strata. Salt deformation has created numerous potential traps, and salt sequences have provided a good seal for the preservation of hydrocarbon accumulations. Large- and small-scale faults related with salt structures have also given favorable migration pathways for oil and gas. When interpreting seismic profiles, special attention needs to be paid to the clastic and carbonate interbeds within the salt sequences because they may lead to incorrect structural interpretation. In the Tarim Basin, the subsalt anticlinal traps are good targets for hydrocarbon exploration.
Added on 31 December, 2013
Discoveries were comparatively sparse, but they persisted steadily throughout the year. Here are some of the more significant discoveries of the past year.
Added on 01 January, 2014
A review of major oil and gas discoveries of 2013 shows a down year in terms of quantity—but that’s not the whole story.
Added on 01 January, 2014
Explorer Director’s Corner
Over the past two decades, advances in technology and political choices to encourage the flow of goods, services and capital across borders have contributed significantly to global economic growth.
Added on 01 November, 2013
Explorer Division Column EMD
Every six months, chairs of the Energy Minerals Division committees convene and report on developments in the areas they cover. In this column, we highlight important observations from these recent reports.
Added on 01 February, 2014
The lessons taken from U.S. shale gas successes hold major implications for China’s energy future, according to researchers at the Energy and Geoscience Institute at the University of Utah. The similarities and potential are explored in a paper to be presented at the AAPG International Conference and Exhibition this month in Istanbul, Turkey.
Added on 01 September, 2014
This year, URTeC has added an enhanced preview of “Coming Attractions.” In addition to looking at established plays, URTeC will provide significant information about emerging unconventional resource possibilities in North America and around the world.
Added on 01 July, 2014
Explorer Historical Highlight
The discovery of giant oil fields in new basins typically occurs only after multiple exploration periods and numerous unsuccessful wells. The first explorers might or might not have the right technical concepts, but for various reasons they fail to find the big prize. This pattern was repeated prior to the discovery of the giant (in place) Liuhua 11-1 Field, Pearl River Mouth Basin, South China Sea.
Added on 01 August, 2014