Title: Shale oil potential of the Upper Cretaceous in the Changling area, Southern Songliao Basin, NE China: perspectives of geochemistry and petrology

Authors: Sandong Zhou; Jiguang Tang; Dameng Liu; Yidong Cai

Addresses: School of Energy Resources, China University of Geosciences, Beijing 100083, China ' Faculty of Earth Sciences, Yangtze University, Wuhan, Hubei 430100, China ' School of Energy Resources, China University of Geosciences, Beijing 100083, China ' School of Energy Resources, China University of Geosciences, Beijing 100083, China

Abstract: The geochemistry and petrology of the Upper Cretaceous Qingshankou and Nenjiang organic-rich shale from the Changling area (CLA) of the southern Songliao Basin located in NE China were investigated to evaluate the shale oil potential. The organic-rich shale ranges from 30 m to 115 m in total thickness, contains kerogen type I and II, and has a total organic carbon (TOC) content of 0.5 wt. % to 11.1 wt. %, with relatively high S1, S2 and hydrogen index (HI). The random vitrinite reflectance (Ro,r) varies from 0.52% to 1.07%, which is in the early-medium thermal evolution stage. The hydrocarbon (HC) potential (S1 + S2) / TOC × 100 generally increases with the burial depth in K2n, while there is no clear correlation between HC potential and burial depth in K2q. The S1 and chloroform bitumen ('A') increase with increasing TOC, which can be divided into three groups: a stable low section, a rising section and a stable high section. Appropriate burial depth, stabilised geological structures and low gas-oil ratio (100-118 m3/t) are favourable for shale oil preservation. From the perspectives of oil generation and storage, the prospective shale oil targets were acquired, which could be divided into three levels. The results show that the amounts of shale oil associated with the K2q and K2n Formations in the CLA is 9.617 × 108 t. The most favourable target areas of shale oil were primarily located at the Chaganhua town and around the Well Y5. [Received: August 10, 2015; Accepted: March 3, 2016]

Keywords: shale oil; Rock-Eval pyrolysis; kerogen type; prospective targets; Songliao Basin; China; geochemistry; petrology; total organic carbon TOC; hydrogen index; vitrinite reflectance; hydrocarbon potential; chloroform bitumen; burial depth; stabilised geological structures; gas-oil ratio.

DOI: 10.1504/IJOGCT.2016.079297

International Journal of Oil, Gas and Coal Technology, 2016 Vol.13 No.3, pp.215 - 242

Received: 22 Aug 2015
Accepted: 03 Mar 2016

Published online: 26 Sep 2016 *

Full-text access for editors Full-text access for subscribers Purchase this article Comment on this article