Time filter

Source Type

Beijing, China

Ning S.,Oil and gas company | Ning S.,Changzhou University | Meijun L.,China University of Petroleum - Beijing | Jinchuan Z.,China University of Geosciences
Applied Mechanics and Materials | Year: 2013

Gas chromatograms of saturated hydrocarbons of shale rock extracts show three patterns of n-alkanets in the second member of Funning formation (E1f2) in Jinhu Sag of Subei basin, eastern China. Three patterns of n-alkanets are the odd-to-even carbon predominance, the even-to-oddcarbon predominance, and the even and odd carbon predominance coexisting, respectively. In this paper, the characteristics of n-alkanet coexisting even and odd carbon predominance and its origin and sedimentary environment are investigated only. The short-chain n-alkanets and long-chain n-alkanets are characterized by pronounced odd carbon predominance, with the dominant carbon of nC15, nC17 and of nC25, nC27, nC29 and nC31. The mid-chain n-alkanets are dominated by even carbon predominance, with the dominant carbon of nC20 and nC22. The composition of biomarkers are characterized by phytane preference, high gamma cerate abundance, the presence of β-carotene and C24-tetracyclic terrapin, which indicate that the organic matter in source rocks deposited in an anoxic, hyper saline lacus trine environment. The biomarkers are no homogeneous, which shows that salinity and redo is not constant in pale-lacus trine. The n-alkanets are mainly derived from algae in the ancient lake and macro pyres on land or around the edges of the ancient lake. The n-alkanets distribution patterns of the dark shale's studied are believed not to be dependent on the redo in the depositional environments or the salinity of the water body, but to be associated with original organic matter composition. © (2013) Trans Tech Publications, Switzerland. Source

Collins S.,Oil and gas company | Lyngra S.,Saudi Aramco
Oilfield Review | Year: 2013

The number of oil and gas wells drilled horizontally continues to increase as operators strive to maximize contact with target formations, develop more-efficient completion programs and optimize recovery from complex geologic structures. Structural steering, a method by which operators direct horizontal and high-angle wellbore trajectories, integrates data from deep-reading LWD resistivity tools and high-resolution imaging devices to create structural models of the geologic conditions encountered by the drill bit. This technique allows drillers to correct wellbore trajectories in anticipation of structural changes ahead of the bit and helps operators better understand the formations already drilled. Copyright © 2013 Schlumberger. Source

Zhou Q.-H.,China University of Petroleum - Beijing | Zhou Q.-H.,Oil and gas company | Song N.,Oil and gas company | Wang C.-Z.,Oil and gas company | And 4 more authors.
Natural Gas Geoscience | Year: 2014

Based on the tectonic, sedimentary, geo-chemistry, reservoir, and gas potential studying, we systematically discusses the forming conditions and characteristics of the Lower Cambrian Niutitang Formation shale gas by using outcrop, drilling, and core data. It indicates that deep shelf and half-bathypelagic sedimentary environment controlled the development and distribution of the Niutitang Formations organic-rich black shale. The black shale is characterized by high thickness, fine kerogen type, rich organic matter content and high thermal evolution. The mineral composition of shale is quartz and clay minerals (illite and montmorillonite mixture), with high siliceous and low carbonate composition. It is useful for absorbing gas and fracturing shale reservoir. Through the geological evaluation and resources calculation, the Niutitang Formation in the Huayuan block has favorable geological conditions for shale gas resources enrichment. Therefore, it is considered as a the practical targets of shale gas exploration and production. Source

Discover hidden collaborations