蒙脱石的成岩转化与油气的形成和初次运移

DIAGENETIC TRANSFORMATIOIN OF MONTMORILLONITE AND PRIMARY MIGRATION OF HYDROCARBON, AND OIL-GAS GENERATION

罗瑞兰 卢书锷 周国清 承大光

Luo Ruilan Lu Shue Zhou Guoqing Cheng Dayuang

地质矿产部石油地质中心实验室

Central Laboratory of Petroleum Geology, Ministry of Geology and Mineral Resources

本文主要通过蒙脱石成岩转化模拟实验,探讨烃类的初次运移。为此,作者选用了不同地区的蒙脱石粘土样品,选择一定的温度、压力和水介质等条件进行成岩模拟实验.同时,对苏北盆地几口井的粘土矿物样品也做了相应的实验和分析。通过这些实验和分析对比,发现这几口井从上至下有着明显的成岩变化规律,现讨论如下。

With the simulation experiments on diagenetic transformation of mont-morillonite,the primary migration of hydrocarbon is studied. Montmorillo-nite clay specimens are selected from various areas and the simulating experiments are carried out with certain conditions of temperature, pressure and water medium.Also the X-ray diffraction and thermal analyses are made on the clay mineral speciments from some wells in North Jiangsu, Depending on the experiments and analogy analysis, the obvious regularity of diagenetic transformation from shallow to deep is discovered, The main mineral compositions in these wells are expansible montmorillonite at depths of about 2000 m, mixed layer clay of non-expansible illite and montmorillonite at depths of 2500-3800m, and non-expansible illite at depths deeper than 3800 m, In addition, clay of montmorillonite-illite mixed layers are found within the related oil and gas beds, which supports the viewpoint that pore interstitial pressure is created by dehydration during the transformation from montmorillonite to illite.It provides a favourable environment for expulsion of liquid hydrocarbons.

https://doi.org/10.11781/sysydz198504257