烃源岩的有机酸生成及其影响因素的模拟实验研究

不同温度下地层水—烃源岩相互作用模拟实验结果表明:（1）在整个实验温度范围内（60～300℃），均有有机酸的生成，有机酸的总浓度在35.4 mg/l至153.9 mg/l之间，其中在100℃和140℃的温度下浓度最大，其它温度下浓度相对较低；（2）在低温（60℃）条件下，成熟度相对较高、有机碳含量较大的烃源岩，有利于生成有机酸，但是在中温（140℃）和高温（180℃、220℃和300℃）条件下，有机酸的生成受有机碳含量、成熟度和碳酸盐含量的多重影响；（3）中低温（60℃和140℃）时，随着碳酸盐含量的增加，有机酸浓度表现为逐渐降低的趋势，表明在60～140℃，有机酸对碳酸盐的溶解和沉淀起主要的控制作用，而高温（180℃、220℃和300℃）条件下，碳酸盐的溶解和沉淀作用受有机酸和CO2的共同控制，从而导致有机酸浓度与碳酸盐的关系变化复杂。

Experimental Study on the Generation of Organic Acids from Source Rocks and Its Effect Factors

The experimental results of formation water source rock interaction in different temperature suggest the following results:(1) organic acid is generated in the experimental temperatures（60～300℃）,the total contents of organic acids is between 35.4 mg/l and 153.9 mg/l. The contents of organic acids are higher in the temperatures of 100℃ and 140℃ than that other temperatures; (2) the source rocks with high maturity （Ro）and high total organic carbon content（TOC）are favorable to the generation of organic acids in the low temperature（60℃）,but the generation of organic acids are commonly controlled by the maturity （Ro）, total organic carbon content（TOC）and carbonate content of source rocks in the middle（140℃）and high temperature（180℃,220℃ and 300℃）;(3)the contents of organic acids gradually decrease with the increase of carbonate content in source rocks in the low and middle temperature（60℃ and 140℃）,it suggests that the dissolution and precipitation of carbonate are mainly controlled by organic acids in the range of 60℃ to 140℃,but the dissolution and precipitation of carbonate are commonly controlled by organic acids and CO2 in the high temperature（180℃,220℃ and 300℃）,it makes the correlation between organic acids and carbonate complicated.