ͨ���Դ���--���ϵ�����Һ��������쳣ѹ���������ƽ��ֲ������о�����ϳ��������������ݻ����������õȷ������쳣��ѹ�ij���; �����ð�ʴ��������������һ�¶ȼ��Ľ���Lee-- Kesler ״̬����ʶ���˹Ž���²����ʴ��ȼ�����ѹ��ϵ��֮��Ĺ�ϵ������--������Һ���������ѹ��ϵ����ƽ���������������𽥽��ͣ������ϳʳ�ѹ( ѹ��ϵ��0. 90 �� 1. 1)����ѹ( ѹ��ϵ��1. 1 �� 1. 4) ������ѹ(ѹ��ϵ��> 1. 4) ����ʽ�ֲ���������ѹ�ʹ�������ܻ��DZ��������쳣��ѹ����Ҫԭ�򡣸����عŽ���²�Ϊ35�� �� 70�棬�Ž���²����ʴ��ȳ�����ع�ϵ����ѹ��ϵ���ʸ���ع�ϵ��˵������--������Һ����ֽ�ѹ���ֲ�״̬�ǵز�̧����ʴ��ɵġ�

Through the research of longitudinal and plane distribution characteristics of abnormal pressure in Xujiahe Formation reservoirs in central and southern Sichuan��the authors analyzed the causes of abnormal high pressure combining with sedimentary background��structural evolution and hydrocarbon generation��and recognized the relationships between ancient and mordern geothermal difference with denudation thickness and pressure coefficients utilizing denudation thickness��homogenization temperature of fluid inclusions and improved Lee-Kesler state equation. The pressure coefficients of the Xujiahe Formation reservoirs decreased in the plane from northwest to south��and appeared to be three-staged in distribution vertically including normal pressure (coefficient as 0. 90 �� 1. 1)��high pressure ( coefficient as 1. 1 �� 1. 4) and superhigh pressure ( as coefficient > 1. 4). The generation pressurization of hydrocarbon and densification of reservoir are the main reasons of abnormal high pressure. The ancient and mordern geothermal difference of gas reservoir is 35�� �� 70�棬and the ancient and mordern geothermal difference is positive relation with denudation thickness and negative with pressure coefficient. The fact shows the present pressure distribution in the Xujiahe Formation in central and southern Sichuan is caused by the uplift and denudation of strata.