# Coupled Evolution of Oil Content and Pore Structure of the Qingshankou Formation Shale, Songliao Basin, Northeastern China: Insights from Thermal Simulation Experiments

## TL;DR

This study explores how oil content and pore structure in shale evolve with thermal maturity, identifying optimal conditions for shale oil exploration in the Songliao Basin.

## Contribution

The study provides new insights into the coupled evolution of oil content and pore structure in shale through thermal simulation experiments.

## Key findings

- Thermal maturity significantly influences oil content and pore characteristics in shale.
- Shale with 1.20%–1.60% maturity shows elevated gas-to-oil ratios and enhanced hydrocarbon fluidity.
- Well-developed pore networks in this maturity range support efficient hydrocarbon extraction.

## Abstract

Oil content estimation
and pore characterization of shale are crucial
for identifying sweet spots in shale plays. Despite extensive research,
the correlation between retained hydrocarbon characteristics and pore
evolution in shale with thermal maturity remains controversial. This
study employs an integrated approach, combining thermal simulation
experiments with multiple analytical techniques, to investigate organic
geochemical characteristics and pore structure evolution across different
maturity stages. The results demonstrate that thermal maturity plays
a significant role in evolution and synergistic changes in oil content
and pore characteristics. Within the optimal maturity of 1.20%–1.60%,
shale has three key favorable characteristics: (1) elevated gas-to-oil
ratios, (2) enhanced fluidity of retained hydrocarbons, and (3) well-developed
pore networks that facilitate efficient hydrocarbon. Combined with
the geological conditions of the Songliao Basin, we identify that
the shale oil in the Gulong Depression with an optimal maturity range
of 1.20%–1.60% is the most promising exploration target.