Abstract
The article presented information about specific of geological conditions depleted oil and gas fields, which has Remaining Oil and Gas in Place. The reasons of abnormally low pressure nascency in the deposit has been analyzed. The article presents information about influence of geodynamic processes and structural and tectonics of Earth crust to formation pressure. The information about availability of initial abnormally low formation pressure in Ukrainian Oil and Gas-Condensate fields has been written. Supposition of nascence the abnormally low formation pressure in difficult oil/water/gas saturation geological formation has been analyzed. The drop of pressure in of initial formation has been analyzed and researched. The article presented that drop of pressure gradient in main Ukrainian oil and gas fields is equal to the value of abnormally low formation pressure.The problems of considerable remaining Oil and Gas in with abnormally low pressure in Ukrainian oil and gas field deposit has been analyzed. The information about oil and gas reservoir conditions of depleted field and brown fields in Ukraine has been analyzed.The plot of the formation pressure gradient decreasing for Chornukhynske, Denysivske, Solokhivske, Druzheliubivske, Tymofiivske and Yablunivske fields has been presented. The drop of pressure to abnormally low in Chornukhynske, Denysivske, Solokhivske, Druzheliubivske, Tymofiivske and Yablunivske fields has been established. The problems of drilling and cementing in the well with abnormally low pressure has been describe. Difficult geological conditions in Ukrainian oil and gas field deposit has been analyzed.The article shows the importance to control parameters of all technological liquids, especially density of drilling and cementing liquid in a time of drilling well with abnormally low pressure. The article shows the aspect of the using of lightweight grouting solutions for mounting wells with abnormally low reservoir pressures, the importance of controlling the contamination of the bottom zone of the formation and preventing the occurrence of hydraulic fracturing during cementing.