Background technique
China's garden basin gravity stream research is more early, and has found a large amount of Accumulation zones, such as in Bohai gulf basin Jiyang
The down warping region town Dongying He Che recess (Shengli Oil Field), Liaohe Depression western sag (Liaohe Oil Field), Jingzhong depression beam deer recess, corridor are solid
Recess and Jin Xian recess (North China Oilfield), deep tectonic process Biyang Sag (Henan Oil Field), Er'lian Basin Jirgalangtu sag, match
The garden basins such as Han Tala recess, Baiyinchagan Depression (North China Oilfield) have found in succession a collection of gravity stream glutenite oil gas field or
Oil-bearing sand bodies, such gravity stream sand body have become east oil gas field it is important take over area.Relative to fault depressed lacustrine basin gravity stream sand body
Exploration progress for, Lacustrine Basins gravity stream sand body oil-gas exploration relatively lags behind, in terms of domestic Lacustrine Basins gravitational flow deposits
Research focus primarily upon Ordos Basin.
With going deep into for oil-gas exploration process, and under the guidance of " Stabilizing Oil Production of Eastern China, development are western " policy, in recent years,
In Longdong Area, Ordos Basin, the deep lake-depth lake region domain discovery of the half of Triassic Yanchang Formation is largely total with phytal zone delta
Raw gravity stream sand body is the favourable places to form Stratigraphic and subtle reservoirs, wherein the petroleum resources contained are extremely abundant.And
Many understanding existing to the Forming Mechanism of gravity stream sand body in the basin at this stage, but mostly qualitative analysis, different type gravity
The planar characteristics of distribution of stream deposit has not been reported.And the plane of Gravity Flow Sediments and longitudinal development scale and distribution characteristics
It is the important indicator established gravitational flow deposits mode, predict gravity stream sand body.Gravity Flow Sediments identification is mainly adopted at this stage
It is carried out with the form of log, combining form.
Existing deposit well logging quantitative identification method multi-solution is strong, and accuracy is low, it is difficult to which reach oil field production needs needle
To the problem, therefore patent applicant has researched and developed a kind of Lacustrine Basins Gravity Flow Sediments well logging quantitative identification method to solve
The certainly problem.
Summary of the invention
In view of the above-mentioned problems, the purpose of the present invention is intended to provide a kind of Lacustrine Basins Gravity Flow Sediments well logging quantitative judge
Method.
For this purpose, the present invention uses following technical scheme:Lacustrine Basins Gravity Flow Sediments well logging quantitative identification method, including
Following steps:
1.1, live core analysis:Lithology, the deposition characteristics phenomenon of live core hole rock core are observed, establishes out and takes
The rock core facies analysis of heart well;It is theoretical according to gravitational flow deposits, the Gravity Flow Sediments type developed in core hole is analyzed, is obtained not
Lithology, structure, the sedimentary structure feature of same type Gravity Flow Sediments;
1.2, Gravity Flow Sediments carry out micro-analysis:Petrographic thin section point is carried out to different type gravitational flow deposits rock
Analysis, obtains its mineral constituent content;
1.3, rock core calibration well logging:On the basis of above-mentioned steps 1.1, the deposit development sequence of cored interval rock is established,
And compare, playback with log, so that corresponding relationship is established in rock core and well logging, on the basis of core Location, carry out
Rock core demarcates different types of log data work, obtains different types of Gravity Flow Sediments in different series log data
Respond style and changing value;
1.4, Logging Identification Method is established:After carrying out different type Gravity Flow Sediments calibration log data, using difference
Log data make cross plot, analyze the recognition effect of different type Gravity Flow Sediments and deep lake mud rock;Maintenance data is dug
Pick method filters out according to the internal relation between different type log data and responds sensitivity to different type Gravity Flow Sediments
Log data and assign corresponding weight, establish the standard of quantitative well logging recognition different type Gravity Flow Sediments;
1.5, validity check:Cored interval with established method to development in half Shen Hu and deep lake region domain carries out gravity
Deposit identification is flowed, the recognition result of recognition result and core observation is compared.
As supplement to above-mentioned technical proposal and perfect, the invention also includes following technical characteristics.
In above-mentioned steps 1.2, for the sheet thickness in 0.03mm, thin slice is that statistics obtains under the microscope in polarized light microscopy
Form type, the content of rock forming mineral.
It can achieve following beneficial effect using the present invention:The present invention is seen in detail in the rock core of Gravity Flow Sediments core hole
On the basis of examining, with the latest theories of gravitational flow deposits as guidance, identifies and sum up different type Gravity Flow Sediments
Deposition characteristics;In conjunction with the micro-analysis of deposit, using the geologic thinking of rock core calibration well logging, building different type gravity stream is heavy
Response characteristic of the product object in different log datas;Based on data digging method, screening to different type Gravity Flow Sediments with
And deep lake mud rock responds good several logging programs, and the response established between the two (Gravity Flow Sediments and well logging) is closed
System;Finally the effect of this method is verified, inspection result shows that established recognition methods is heavy to the gravity stream in research area
Product object quantitative judge works well, and the thinking can be used for other regions.
Specific embodiment, the present invention take following steps to identify:
1. live core analysis
Description is examined to lithology, the deposition characteristics phenomenon of core hole rock core, establishes out the rock core facies analysis of core hole;
According to gravitational flow deposits latest theories, the gravity stream type developed in the core hole of analysis and observation sums up different type gravity
Flow the feature (including lithology, structure, sedimentary structure) (table 1) of deposit.
Table 1 studies area's Gravity Flow Sediments type and its fluid properties, transported deposit mechanism and distinguishing mark table
2. Gravity Flow Sediments micro-analysis
Petrographic thin section (0.03mm is thick) is ground to the rock that different type Gravity Flow Sediments are formed, under petrographic microscope
Observation, identification, type, the content for counting composition rock forming mineral, the especially content of brittle mineral and shale.
3. rock core calibration well logging
On the basis of core observation, establish the deposit development sequence of cored interval rock, and with log (especially GR
Curve) it compares, playback, so that rock core and both data of logging well establish true depth corresponding relationship.
4. establishing Logging Identification Method
On the basis of core Location, carries out rock core and demarcate different types of log data work.Utilize log data pair
The recognition methods of four seed type Gravity Flow Sediments is:
1. being identified on rock core well to Gravity Flow Sediments, always according to the identification marker of different Gravity Flow Sediments
6 kinds of deep lake rock types are identified altogether, such as Sandy debris flows deposition (i.e. block-like clean sandstone), turbidity current deposit, slump rock, are rich in
Mud boulder Sandy debris flows deposition, the old and deep lake mud rock of shale clast stream;
2. making cross plot using different log datas, the recognition effect of 6 type moldeed depth lake rocks is analyzed.The study found that
After interval transit time curve AC and resistivity curve RT makees cross plot, different types of depth lake rock distribution is irregular;Natural gamma
After curve GR and resistivity curve RT makees cross plot, foundation GR value is only capable of by both shale debris flow deposit and deep lake mud rock and its
He distinguishes four seed type gravitational flow deposits, and the boundary line delimitation of GR value cannot be defined accurately.
3. using data digging method, according to the internal relation between different type log data, 6 log numbers are filtered out
According to and assign corresponding weight, as gamma ray curve GR, resistivity curve RT, interval transit time curve AC, density curve DEN,
Shale content SH and neutron porosity CNL, weighted value are respectively 0.73,0.12,0.07,0.05,0.03,0.
4. after data mining, obtaining the recognition mode of 6 kinds of deep lake rock type.Deep lake mud rock, the Ω of RT≤31.1 m, GR>
99.37API;Shale debris flow deposit, RT>31.1 Ω m, GR>99.37API;Sandy debris flows deposition, the μ of AC≤224.81 s/
M, GR≤79.09API;Develop the turbidity current deposit of positive grain sequence, SH≤17.47%, AC>224.81 μ s/m, GR≤79.09API;It is sliding
Collapse rock, SH>17.47%, AC>224.81 μ s/m, GR≤79.09API;Develop the turbidity current deposit of imperfect Bouma sequence, DEN>
2.57g/cm3, GR>79.09API;It is deposited rich in mud boulder Sandy debris flows, DEN<2.57g/cm3, GR>79.09API.
5. validity check
Accuracy, which reaches, to be identified to 69 samples in half Shen Hu and deep lake region domain to development with established method
86.96% (table 2).Therefore, the curve screened based on 6 kinds, to the deep lake rock type in 6 kinds of area of research (in 5 Gravity Flow Sediments and
A kind of depth lake mud rock) it can effectively be identified.
2 data digging method of table identifies deep lake rock effect statistical form
The present invention first by based on core hole core observation, the identification of indoor petrographic thin section and well-log information, into
Row Gravity Flow Sediments type identification, lithology, sedimentary structure are summarized.Based on direct data (different type Gravity Flow Sediments
Rock core) calibration secondary source (well-log information) geology thought, it is preferably heavy to different type gravity stream using data digging method
Product object responds good logging program, in conjunction with the macro and micro analysis of rock core, establishes different Gravity Flow Sediments and deep lake mud
The log response standard of rock.Finally this method is verified based on core hole.
The present invention breaches at this stage with the multi-solution that is encountered of well-log information identification different type deposit is strong, precision has
The technical bottleneck of limit solves to reach the different types of Gravity Flow Sediments rich in petroleum resources and accurately quantitatively know
Not, believable theory and technology branch can be provided in longitudinal direction and plane distribution law study for realization different type Gravity Flow Sediments
It holds, is conducive to establish the gravitational flow deposits mode that can more react Lacustrine Basins.
The above shows and describes the basic principles and main features of the present invention and the advantages of the present invention.The technology of the industry
Personnel are it should be appreciated that the present invention is not limited to the above embodiments, and the above embodiments and description only describe this
The principle of invention, without departing from the spirit and scope of the present invention, various changes and improvements may be made to the invention, these changes
Change and improvement all fall within the protetion scope of the claimed invention.The claimed scope of the invention by appended claims and its
Equivalent thereof.