Method for improving the spatial resolution of resistivity logging
Збережено в:
| Опубліковано в: : | Геофизический журнал |
|---|---|
| Дата: | 2010 |
| Автор: | |
| Формат: | Стаття |
| Мова: | English |
| Опубліковано: |
Інститут геофізики ім. С.I. Субботіна НАН України
2010
|
| Онлайн доступ: | https://nasplib.isofts.kiev.ua/handle/123456789/102592 |
| Теги: |
Додати тег
Немає тегів, Будьте першим, хто поставить тег для цього запису!
|
| Назва журналу: | Digital Library of Periodicals of National Academy of Sciences of Ukraine |
| Цитувати: | Method for improving the spatial resolution of resistivity logging / N. Myrontsov // Геофизический журнал. — 2010. —Т. 32, № 4. — С. 119-121. — англ. |
Репозитарії
Digital Library of Periodicals of National Academy of Sciences of Ukraine| id |
nasplib_isofts_kiev_ua-123456789-102592 |
|---|---|
| record_format |
dspace |
| spelling |
Myrontsov, N. 2016-06-12T03:54:26Z 2016-06-12T03:54:26Z 2010 Method for improving the spatial resolution of resistivity logging / N. Myrontsov // Геофизический журнал. — 2010. —Т. 32, № 4. — С. 119-121. — англ. 0203-3100 https://nasplib.isofts.kiev.ua/handle/123456789/102592 en Інститут геофізики ім. С.I. Субботіна НАН України Геофизический журнал Method for improving the spatial resolution of resistivity logging Article published earlier |
| institution |
Digital Library of Periodicals of National Academy of Sciences of Ukraine |
| collection |
DSpace DC |
| title |
Method for improving the spatial resolution of resistivity logging |
| spellingShingle |
Method for improving the spatial resolution of resistivity logging Myrontsov, N. |
| title_short |
Method for improving the spatial resolution of resistivity logging |
| title_full |
Method for improving the spatial resolution of resistivity logging |
| title_fullStr |
Method for improving the spatial resolution of resistivity logging |
| title_full_unstemmed |
Method for improving the spatial resolution of resistivity logging |
| title_sort |
method for improving the spatial resolution of resistivity logging |
| author |
Myrontsov, N. |
| author_facet |
Myrontsov, N. |
| publishDate |
2010 |
| language |
English |
| container_title |
Геофизический журнал |
| publisher |
Інститут геофізики ім. С.I. Субботіна НАН України |
| format |
Article |
| issn |
0203-3100 |
| url |
https://nasplib.isofts.kiev.ua/handle/123456789/102592 |
| citation_txt |
Method for improving the spatial resolution of resistivity logging / N. Myrontsov // Геофизический журнал. — 2010. —Т. 32, № 4. — С. 119-121. — англ. |
| work_keys_str_mv |
AT myrontsovn methodforimprovingthespatialresolutionofresistivitylogging |
| first_indexed |
2025-11-25T20:28:07Z |
| last_indexed |
2025-11-25T20:28:07Z |
| _version_ |
1850523482477035520 |
| fulltext |
������������������ !�"�#$�%&�'�$��(�( ��2
)*� ��+,�*-�.
��,������/
�*
��.,�.��.���*������ �����
��
Method for improving the spatial resolution
of resistivity logging
N. Myrontsov, 2010
Institute of Geophysics, National Academy of Sciences of Ukraine, Kiev, Ukraine
myrontsov@ukr.net
The main aim of resistivity logging is to deter-
mine geometric and electrical parameters of a model
of borehole environment. Subsequent problems of
geophysical investigations of well, such as deter-
minations of fluid saturation, daily flow of fluid pro-
duction and others will be solved the more precise-
ly, the more precisely these parameter are deter-
mined. Sounds in the complex differ each from oth-
er as to the depth of investigation and the vertical
resolution (along the axe of well). Naturally, the ver-
tical resolving power is worse for sounds with larger
depth of investigation. In this connection, the ne-
cessity to build sounding system for logging with
the maximum high vertical resolution of all sounds
including the most subsurface ones.
A creation of such equipment based on tradi-
tional principles is complicated by the necessity to
use frequency, spatial or time separation, what com-
plicates considerably the design (a creation of ef-
fective equipment with more than two sounds was
found practically impossible). A creation of such
equipment for induction logging are also complica-
ted because of fundamental design limitations.
A factorization is believed an affective approach
to create sounding system for logging with the maxi-
mum high vertical resolution of all sounds including
the most subsurface ones. The factorization permits
to solve separately the inverse problem along the axe
of well and along a normal to it. It means that in each
point of sound’s position we can believe that the bed
has infinite thickness (is free of shoulder effect). In
this case, the conductivity values will change only
along the normal to the axe of well.
The following methodical approach was used for
induction logging: to determine the resistivity ac-
cording to the apparent resistivity measured within
the frame of the linear Doll theory using a solution
of the first kind Fredholm equation of convolution
type. The present method was tested on model
material from various complexes (4IK, 7IK, AIT
Schlumberger). The example of application of such
method to data of 4IK equipment is shown in Fig. 1
(sounds: I0.5; I0.85; I1.25; I2.05. The numbers cor-
responds to the length of each sounds). It is evident
that using the proposed approach permits to factori-
ze the problem with high degree of accuracy. In the
work, it is also shown that after such factorization
the vertical resolution of each sound is limited only
by the error of measurement and the value of re-
cording step along the axe of well.
�������
����
���� ����
��( ������������������ !�"�#$�%&�'�$��(�(
tively incorrect results. One of obvious advantages
of described method consists in its applicability to
already existing equipment of inductivity logging.
In contrast to inductivity logging problems, the
problems of electric logging are nonlinear in essence.
So, the variant of algorithmic solution is inapplicab-
le for electric logging. In this work, the new type of
multisound electric logging equipment (MEK) is pro-
posed. The principle of lateral logging, but without a
necessity of frequency, spatial and time separation,
is used as principle of its action.
The idea of the method consists in the possibili-
ty to realize a simultaneous measurement of cur-
rents, every of which penetrates down to strictly
defined depth. In this case, high vertical resolution
is reached by means of use of the principle of late-
ral logging.
The example of MEK borehole logs for invaded
profile is shown in Fig. 2. It is evident that proposed
method also factorizes the problem with high de-
gree of accuracy. It is demonstrated that the verti-
cal resolution of each sound is limited mainly by
the error of measurement and the value of step re-
cording along the axe of well as well as the sound’s
size.
The MEK design and the principle of measure-
ment proposed in the work have a number of advan-
tages: the possibility to be used in horizontal wells;
the insusceptibility to the Groningen effect; the con-
structive ease of realization and small overall dimen-
sions.
Fig. 1. The example of factorization of 2D inverse problem of
inductive logging: I — depth, II — measured apparent con-
ductivity and specified conductivity of beds, III — recon-
structed conductivity.
The assumption on absence of current interac-
tion in medium also is a restriction of this method.
This restriction is not critical since the linear Doll
approach describes many cases being topical for
practice with high degree of accuracy. Besides, a
lot of authors linearize the problem using a correc-
tion for skin effect. In the course of investigation, it
was shown that use of correction for skin effect is
only some approximation, which introduces its own
error being, in essence, unavoidable, but it permits
to find some, undoubtedly approximate, solution.
The modelling has shown that solution based on
using a correction for skin effect can lead to qualita-
Fig. 2. The example of factorization of 2D inverse problem of
electric logging: MEK1, MEK2, MEK3, MEK4 are resistivities
obtained by different depth sounds; Rp is the resistance of
virgin part of bed; Rzp is the resistance of invaded zone.
������������������ !�"�#$�%&�'�$��(�( ���
)*� ��+,�*-�.
��,������/
�*
��.,�.��.���*������ �����
��
The effic��� $��#�&��&�����%��������#���� ���
�������� ��7��$���""��"�:�������$;������������� ��8
���������#�<�������'���������������(���&��8(�����!
��&���������=������"��������#�&��#��%�������$����
���� �� ������������>?@������)A���7��%� ��������
���� ������� ���� comparison with commonly used
BKZ-BK-IK complex and some of other multisound
complexes used on the territories of Ukraine, Rus-
sia, Kazakhstan and other countries was made.
They also are not inferior to similar complexes de-
veloped by leading geophysical corporations as to
their characteristics.
|