3D-Basin Modeling of the Changling Depression, NE China: Exploring Petroleum Evolution in Deep Tight Sandstone Reservoirs

Jinliang Zhang,Yang Li,Zhongqiang Sun,Jiaqi Guo

doi:10.3390/en12061043

Abstract

The Changling Depression is the largest and most resource-abundant reservoir in the South Songliao Basin, NE China. The petroleum evolution rules in the Lower Cretaceous deep tight sandstone reservoir are unclear. In this study, 3D basin modeling is performed to analyze the large-scale petroleum stereoscopic migration and accumulation history. The Changling Depression has a complex fault system and multiple tectonic movements. The model is calibrated by the present formation temperatures and observed maturity (vitrinite reflectance). We consider (1) three main erosion episodes during the burial history, one during the Early Cretaceous and two during the Late Cretaceous; (2) the regional heat flow distribution throughout geological history, which was calibrated by abundant measurement data; and (3) a tight sandstone porosity model, which is calibrated by experimental petrophysical parameters. The maturity levels of the Lower Cretaceous source rocks are reconstructed and showed good gas-generation potential. The highest maturity regions are in the southwestern sag and northern sag. The peak hydrocarbon generation period contributed little to the reservoir because of a lack of seal rocks. Homogenization temperature analysis of inclusions indicated two sets of critical moments of gas accumulation. The hydrocarbon filling in the Haerjin and Shuangtuozi structures occurred between 80 Ma and 66 Ma, while the Dalaoyefu and Fulongquan structures experienced long-term hydrocarbon accumulation from 100 Ma to 67 Ma. The homogenization temperatures of the fluid inclusions may indicate a certain stage of reservoir formation and, in combination with the hydrocarbon-accumulation simulation, can distinguish leakage and recharging events.

Highlights

The Changling fault depression is the largest petroliferous block in the southern Songliao Basin (Figure 1), which covers a total area of 1.3 × 104 km2 [1]
We focus on the lower set of the petroleum we selected four representative deep wells to indicate the locations: The Changling 1 gas field
After investigating the stratigraphic we found that scholars provided different classification schemes [3,4,52]

Summary

Introduction

The Changling fault depression is the largest petroliferous block in the southern Songliao Basin (Figure 1), which covers a total area of 1.3 × 104 km2 [1]. Hydrocarbon accumulation has mostly occurred in Cretaceous strata at a burial depth of 2000~4000 m. Upper Cretaceous hydrocarbon deposits were discovered and explored years ago and the petroleum evolution processes have been discussed [2,3,4]. Lower Cretaceous reservoirs did not receive sufficient attention because of their deep burial depth until unconventional reservoirs and tight gas became the research hotspots [5,6,7,8,9,10,11]. The Denglouku Formation (K1 d) is a typical tight sandstone reservoir. The porosity of K1 d is between 0.3% and 10.4% and the average porosity is 5.4%, Energies 2019, 12, 1043; doi:10.3390/en12061043 www.mdpi.com/journal/energies

Results

Discussion

Conclusion