In the Dushan Formation of the Middle Devonian in the southern Guizhou province, the mudstone source rocks of trough-basin facies are widespread with high organic abundance. The average organic carbon content is 3. 02% . Most of the kerogens are of type Ⅱ1 , and some are of type Ⅰ, indicating for excellent hydro-carbon generation conditions. In carbonate and sandstone reservoirs, intergranular, intergranular pores and cracks develop well. Cap rocks distribute widely and are preserved well, indicating for strong sealing capacity. Petroleum shows prove that, in both carbonate and sandstone reservoirs in the Middle Devonian, uneven organic matter or asphalt infillings can be found. The homogenization temperatures of fluid inclusions in the Dushan For-mation show that the study area has experienced 2 phases of hydrocarbon charging. At the end of Devonian, the southern Guishou province was the uplifting area of the Ziyun Movement, hence was favorable for petroleum charging during the early Carboniferous. Petroleum migrated along cracks to the reef flat limestone reservoirs and the littoral sandstone reservoirs in platforms and platform edges.% 贵州南部槽盆相沉积的中泥盆统独山组泥质烃源岩分布广泛，有机质丰度高，有机碳含量平均3.02%，干酪根显微组分显示以Ⅱ1型为主，少量为Ⅰ型，显示极好的生烃条件.碳酸盐岩和砂岩储层晶间、粒间孔隙及裂缝均十分发育，储集性能较好.盖层广泛分布，保存完好，具有较强的封盖性.油气显示表明，中泥盆统碳酸盐岩储层及砂岩储层中，均可见到不均匀有机质浸染或沥青充填.独山组中包裹体均一温度显示，该区具有两期油气充注.泥盆纪末期，贵州南部正处于紫云运动的抬升隆起区，成为早石炭世生油高峰阶段油气充注的有利区域，油气沿断裂向台地、台地边缘礁滩相灰岩储层及滨岸相砂岩储层运聚，可形成一定规模的油气藏.
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