Buying the well or investing money in re-completion without thorough and detailed Geological and Geophysical analysis, without calculating the residual reserves and financial profits, without defining the main causes of falling production rate and without determining the most effective method of treatment for increase the flow, it is a purchase "a pig in a poke".


Well operation/exploitation history (Production Data)

monthly/daily productive inflow of oil, gas and water

number of productive and non-productive days per month

start and end (maximum and minimum) debit

tubing pressure (internal pressure of productive formation)

extent the fall of productive inflow

stops and possible transitions to the next productive intervals

All possible test's results





All possible logging (logs)

induction (electric) log

neutron and gamma-ray

acoustic (casing/cement) log

mud-log, chat-log, etc.

Well position map (preferably with an altitude)

position and distance relative to the neighboring production wells

position and distance relative to the nearest injection wells

All possible well documentation


design/construction (depths and casing (OD/ID)

opened productive intervals

techniques of opening the productive formations (casing, cement, productive formation)

using of hydraulic fracturing, chemical treatment, stimulation, etc.

previous closing and transitions to new productive intervals

packers, retainers, cementing, insulation/waterproofing, etc.

Core analysis, lithology, etc. (Core)

core analysis or

rock photos

From “Production Data” seen the beginning and the end of exploitation, monthly/daily productive inflow of oil, gas and water (extent of water flooding), the number of productive and non-productive days per month, start and end (maximum and minimum) debit, tubing pressure (internal pressure of productive formation), extent the fall of productive inflow, stops and possible transitions to the next productive intervals. Using the method of mathematical and graphical analysis it is possible to calculate the residual reserve (by oil, gas, and water) and an operating time of the well before and after re-completion, and most importantly, make the initial conclusion about the suitability of this well for re-completion. 

From “logging data” can be made conclusions about overlying rocks, productive and water layers, water proximity to the wellbore, previously opened/exploited intervals, identify missing productive reservoirs, percentage content of oil, gas, and water saturation, salt content, percentage content of porosity and permeability, gravity and viscosity, borehole depth (TD, TDPB), internal temperature of the productive formation, inner (ID) diameter of casing, make a correlation with neighboring oil, gas or injection wells, determine the best intervals for complete opening (re-opening) the productive formation, and lots of other important information.


Deposit-field analysis

major characteristics of producing field

development history, geology, lithology, physics, location, position, size, extent, stratification, content, rocks, core, etc.

wells, drilling grid, interwell distances, development and exploitation history, locations, positions, depths, productive formations, particular qualities, etc.

deposit-field overall evaluation


Well analysis

well position relative to neighboring oil or gas and injection wells

productive layers, absolute elevations 

development and exploitation history, well design, methods of opening and stimulation, etc.

core/rock analysis , lithology, productive and unproductive formations

porosity, permeability, pore’s structure

oil saturation, gas saturation, water saturation, formation pressure

water-bearing layers, missing productive layers

correlations with neighboring wells

Technological parameters

residual reserves of oil, gas and water

financial expenses and profits

recommendations and methods of well re-completion

calculation of technological parameters

technological project and program

technological tack and schedule

operating recommendations after well re-completion