Horizontal Wells. Problems and Prospects 2015

This article describes the preparation of production logging on coiled tubing in extended reach horizontal wells, its implementation and ways of solving the difficulties encountered during implementation, along with examples of the work and the results of the first campaign in Russia for the memory production logging on coiled tubing in the North Caspian offshore field. It also describes the experience of this campaign, during which all the goals were achieved without any HSE incidents

The paper deals with numerical simulation and analysis of direct current and high-frequency electromagnetic logging data obtained in high-angle and horizontal oil-and-gas wells. The lateral sonde responses in inclined wells are calculated, with their main features being revealed. Software for electromagnetic data real-time processing and quantitative interpretation is developed to evaluate electrophysical properties of fluid-saturated reservoirs. Some examples of analysis and inversion of electromagnetic logging data measured in a subhorizontal well are provided. They demonstrate a capability to estimate the resistivity of a formation, as well as to determine the distance to a boundary and the angle between the hole and the boundary. The up-to-date software considerably increases the efficiency of geophysical logging systems employment.

Microseismic hydraulic fracturing monitoring from a surface is complicated by high noise and low-level of signal from the events. The report presents the results of the Full-Wave Location method (FWL) for hydraulic fracture monitoring to determine the location and character of events, even when the signal/noise ratio at the receivers is comparable to 1/100. Are presented the result of the monitoring of natural active fractures in the formation.

Srednebotuobinskoe oil and gas-condensate field is one of the giant fields in East Siberia (Russia) that is developed since 2013. Main production target is botubinskiy horizon named layer Bt which is consists of terrigenous sediments and it differs by monolithic structure with wide gas cap and bottom water. There is no barriers between saturation zones of the field. Therefore all the reserves of the field are contact. The key solution of the development of reservoir Bt is application of horizontal wells. After start of the pilots in the the gas-oil- water zone (GOWZ) of the field the primary problems have appeared at the well performance. They were gas coning and early gas breakthrouhg to the bottom well. On the pilot stage there is no the conseption of geometry well and selection of well operation coditions. It is presented in the article the justification of the approach to the gas-oil-water zones development of the field by horizontal wells taking account two factors: geometry of the wells in relation to gas oil contact and control of the well operation coditions.

The possibility of simultaneous estimation of reservoirs porosity and gas saturation based on “porosity” geophysical methods – neutron-neutron and gamma-gamma density logging without using petrophysical functions, such as core – log data correlation, is described in the article

he largest oil and gas companies own high-tech centers of support drilling wells, which allows to provide expert support drilling in real-time maximize the effectiveness of drilling. Smart tracking drilling, regardless of geography conducting these works allows for real-time view of the necessary information about the structure of the reservoir, to make optimal decisions for wiring and construction wellbore.

Companies thus have reduced geological risks during construction wells. Use of advanced technology, scientific potential of the Institute «KogalumNIPIneft» can successfully solve these problems for the needs of LLC «LUKOIL-Western Siberia». To this end, the institute «KogalumNIPIneft» a specialized group that provides geophysical support for drilling horizontal wells and sidetracks with horizontal end at all stages of the technological chain.

The main instrument of the group has long been software system that ensures «GeoPoisk» problem solving, but with the rise the number of wells being drilled and the increasing complexity of the geology maintained facilities there the need to find more effective solutions

This report is a generalization of practical experience in the area of geosteering for drilling horizontal wells in Western Siberia using 3D geological model.

The main aspect considered is a structural uncertainty, which leads to several equally probable variants of determining the position of the wellbore in the target formation. As a consequence there are significant risks of decrease in drilling efficiency and well deliverability. Cases of geosteering in areas of low geological and geophysical exploration, and lateral reservoir heterogeneity are considered.

To reduce possible risks and to increase reliability of the forecast using geological models the authors recommend the following: deviation measurements with gyroscopes, using seismic interpretation results in geological modelling, using the geosteering technology.

The authors took part in planning and geosteering of more than 150 wells with horizontal tailing-in using live simulation models. By using the author’s approach, collector well drilling efficiency has been increased from 65 to 80% of the wellbore length.

Currently, there is great interest in the different ways of well stimulation. In the present report we consider one of the ways – horizontal well with multistage fracturing. Interval selection for the packers and ports of fracture initialization is based on the use of several methods: interconnecting petrophysical and geomechanical data. The main input parameters – brittleness and well volume model

Digital model data have gotten while a horizontal well drilling.

The article addresses the fundamental questions about how use this type of data in numerical models. Consideration of proposed approaches are being illustrated with the results obtained in carrying out works on the terrigenous and carbonate fields in Western and Eastern Siberia.