CN104636592A - Method for obtaining indication mark of oil layer through conventional logging - Google Patents

Abstract

The invention discloses a method for obtaining an indication mark of an oil layer through conventional logging. The method comprises the following steps that 1, conventional logging data are read from a data file; 2, stratum parameters of a local area are tested and computed; 3, the porosity phi is computed according to a logging curve; 4, the electrical resistivity of apparent formation water is computed; 5, the indication mark of the oil layer at a depth point is computed; 6, after computing of one depth point is finished, the first step is carried out again until computation of the whole depth section is finished. The method can effectively mark out the oil producing interval, is high in accuracy, obviously relieves the labor intensity of interpreters, and can be widely applied to the field of petroleum exploration and development.

Description

The method of oil reservoir Warning Mark is obtained by conventional logging

Technical field

The present invention relates to Petroleum finance, particularly relate to a kind of method being obtained oil reservoir Warning Mark by conventional logging.

Background technology

Formation resistivity is one of parameter of reflection reservoir oil-containing or gassiness, but the vertical or horizontal change of reservoir water salinity can cause the change of resistivity, the judgement of interference on oil-gas-water layer: the impact of shale index, the resistivity at oil reservoir place is reduced, the judgement of interference to oil-gas-water layer: well is expanding, and the required factor of porosity that makes to log well is higher than true hole porosity, water layer can be mistaken for oil reservoir.

Summary of the invention

The object of the invention is the deficiency in order to overcome above-mentioned background technology, providing a kind of method being obtained oil reservoir Warning Mark by conventional logging, can effectively mark off can oil producing interval, high, the remarkable working strength reducing commentator of accuracy.

A kind of method being obtained oil reservoir Warning Mark by conventional logging provided by the invention, is comprised the steps: step one, from data file, reads conventional logging data; Step 2, test calculate this area formation parameter; Step 3, calculate factor of porosity φ according to logging trace; Step 4, calculating apparant formation water resistivity; The oil reservoir Warning Mark of step 5, compute depth point; After step 6, a depth point have calculated, get back to step one, until entire depth section has calculated.

In technique scheme, in described step one, described conventional logging data comprise: the degree of depth, interval transit time, hole diameter, neutron, density, natural gamma, deep investigation resistivity, shallow investigation resistivity and spontaneous potential.

In technique scheme, in described step 2, described this area formation parameter comprises: A Erqi cementation factor m, A Erqi constant a, formation water resistivity R _w, apparant formation water resistivity minimum value R _wmn, apparant formation water resistivity maximal value R _wmx, natural gamma ray log value maximal value GR _max, natural gamma ray log value minimum value GR _min, bit diameter BITS.

In technique scheme, test and calculate formation water resistivity R _wtime, need to carry out temperature correction according to each depth point.

In technique scheme, in described step 3, described logging trace comprises interval transit time, neutron and density.

In technique scheme, in described step 4, described apparant formation water resistivity: in formula: R _wa-apparant formation water resistivity, R _d-deep investigation resistivity, φ-formation porosity, m-A Erqi cementation exponent, a-A Erqi constant.

In technique scheme, in described step 5, the oil reservoir Warning Mark of described depth point: $\mathrm{OIL}=(\frac{R_{\mathrm{wa}}-R_{\mathrm{wmn}}}{R_{\mathrm{wmx}}-R_{\mathrm{wmn}}}-\frac{\mathrm{GR}-{\mathrm{GR}}_{\min }}{{\mathrm{GR}}_{\max }-{\mathrm{GR}}_{\min }})(1-\frac{\mathrm{CAL}-\mathrm{BITS}}{\mathrm{BITS}}),$ In formula: OIL-oil reservoir Warning Mark, R _wa-apparant formation water resistivity, R _wmn-apparant formation water resistivity minimum value, R _wmx-apparant formation water resistivity maximal value, GR-natural gamma ray log value, GR _min-natural gamma ray log value minimum value, GR _max-natural gamma ray log value maximal value, CAL-hole diameter, BITS-bit diameter.

The present invention obtains the method for oil reservoir Warning Mark by conventional logging, there is following beneficial effect: before meticulous well logging interpretation, with the oil reservoir Warning Mark that the present invention calculates, can effectively mark off can oil producing interval, commentator is emancipated from hard work.Current test findings shows, there is oily output in every place having instruction, every place not having to indicate, formation testing or water outlet, or is dried layer.Therefore adopt the present invention, significantly reduce the cost to non-payzone formation testing, and make explanation staff concentration in there being oil reservoir to indicate the analysis of interval.

Accompanying drawing explanation

Fig. 1 is the present invention obtains the method for oil reservoir Warning Mark schematic flow sheet by conventional logging;

Fig. 2 is that the present invention obtains the payzone section schematic diagram of the refined spy in embodiment Ya Bulai area L well formation testing in the method for oil reservoir Warning Mark by conventional logging.

Embodiment

Below in conjunction with drawings and Examples, the present invention is described in further detail, but this embodiment should not be construed as limitation of the present invention.

See Fig. 1, the present invention obtains the method for oil reservoir Warning Mark by conventional logging, comprises the steps:

Step one, from data file, read conventional logging data, described conventional logging data comprise: the degree of depth (m), interval transit time (μ s/m), hole diameter (in or cm, in and inch), neutron (%), density (g/cm ³), natural gamma (API), deep investigation resistivity (Ω m), shallow investigation resistivity (Ω m) and spontaneous potential (mV);

Step 2, test calculate this area formation parameter, described this area formation parameter comprises:

A Erqi cementation factor m,

A Erqi constant a,

Formation water resistivity R _w, R _wneed to carry out temperature correction according to each depth point, (Ω m),

Apparant formation water resistivity minimum value R _wmn, (Ω m),

Apparant formation water resistivity maximal value R _wmx, (Ω m),

Natural gamma ray log value maximal value GR _max, (API),

Natural gamma ray log value minimum value GR _min, (API),

Bit diameter BITS, (in or cm);

Step 3, by related software, calculate factor of porosity φ according to these logging traces of interval transit time, neutron and density;

Step 4, calculating apparant formation water resistivity:

$R_{\mathrm{wa}}=\frac{R_D{\mathrm{\φ}}^m}{a},$

In formula: R _wa-apparant formation water resistivity, (Ω m),

R _d-deep investigation resistivity, (Ω m),

φ-formation porosity, decimal,

M-A Erqi cementation exponent,

A-A Erqi constant;

The oil reservoir Warning Mark of step 5, compute depth point:

$\mathrm{OIL}=(\frac{R_{\mathrm{wa}}-R_{\mathrm{wmn}}}{R_{\mathrm{wmx}}-R_{\mathrm{wmn}}}-\frac{\mathrm{GR}-{\mathrm{GR}}_{\min }}{{\mathrm{GR}}_{\max }-{\mathrm{GR}}_{\min }})(1-\frac{\mathrm{CAL}-\mathrm{BITS}}{\mathrm{BITS}}),$

In formula: OIL-oil reservoir Warning Mark,

R _wa-apparant formation water resistivity, (Ω m),

R _wmn-apparant formation water resistivity minimum value, (Ω m),

R _wmx-apparant formation water resistivity maximal value, (Ω m),

GR-natural gamma ray log value, (API),

GR _min-natural gamma ray log value minimum value, (API),

GR _max-natural gamma ray log value maximal value, (API),

CAL-hole diameter, (in or cm),

BITS-bit diameter, (in or cm);

After step 6, a depth point have calculated, get back to step one, until entire depth section has calculated.

The present invention obtains the method for oil reservoir Warning Mark principle of work by conventional logging is as follows:

(1) concrete meaning of apparant formation water resistivity

In the area that reservoir water salinity is constant, this area can be considered as standard water layer, can apply and comprise Archie equation reverse formation water resistivity:

$R_w=\frac{R_0{\mathrm{\φ}}^m}{a}$

In formula: R _wresistivity of water in-formation pore, (Ω m),

R ₀the resistivity of-100% water-bearing strata, (Ω m),

φ-formation porosity, decimal,

M-A Erqi cementation exponent,

A-A Erqi constant.

If can not find standard water layer, but still press the resistivity of this formulae discovery formation pore space fluid, be referred to as apparant formation water resistivity:

$R_{\mathrm{wa}}=\frac{R_D{\mathrm{\φ}}^m}{a}$

In formula: R _wa-apparant formation water resistivity, (Ω m),

R _d-deep investigation resistivity, (Ω m),

φ-formation porosity, decimal,

M-A Erqi cementation exponent,

A-A Erqi constant;

(2) factor of apparant formation water resistivity is affected

Salinity changes: in explanation interval, node-by-node algorithm goes out an apparant formation water resistivity curve, gets the minimum value of each layer mean value as Rw.In addition, in explanation interval, if reservoir water salinity is change, then the change of each layer salinity should be considered.

Shale: at oil reservoir place, often R _wahigher, can R be used _wacarry out its oiliness of qualitative instruction, certainly, if there is the impact of shale, the R of oil reservoir _waalso may not be high;

Well is expanding: R _waalso depend on water-filled porosity, in the place of borehole condition difference, porosity log will make factor of porosity increase by expanding or rough impact of the borehole wall of hole diameter, increase number often have certain relation with hole diameter, make in expanding place, be not oil reservoir originally, also try to achieve higher R _wa, thus cause erroneous judgement.

(3) well logging estimation oil reservoir Warning Mark

Considering that the oil reservoir Warning Mark under shale, hole diameter and reservoir water salinity situation of change is as follows:

$\mathrm{OIL}=(\frac{R_{\mathrm{wa}}-R_{\mathrm{wmn}}}{R_{\mathrm{wmx}}-R_{\mathrm{wmn}}}-\frac{\mathrm{GR}-{\mathrm{GR}}_{\min }}{{\mathrm{GR}}_{\max }-{\mathrm{GR}}_{\min }})(1-\frac{\mathrm{CAL}-\mathrm{BITS}}{\mathrm{BITS}})$

In formula: OIL-oil reservoir Warning Mark,

R _wa-apparant formation water resistivity, (Ω m),

R _wmn-apparant formation water resistivity minimum value (ideally as actual formation water resistance rate), (Ω m),

R _wmx-apparant formation water resistivity maximal value (ideally regarding actual oil reservoir apparant formation water resistivity maximal value as), (Ω m),

GR-natural gamma ray log value, (API),

GR _min-natural gamma ray log value minimum value, (API),

GR _max-natural gamma ray log value maximal value, (API),

CAL-hole diameter, (in or cm),

BITS-bit diameter, (in or cm).

Oil reservoir Warning Mark example

As a kind of new oil-water layer identification method, the method being obtained oil reservoir Warning Mark by conventional logging is having the interval of display, can be corresponding with well logging result, below with the payzone section of Ya Bulai area formation testing for embodiment is set forth:

Fig. 2 is the refined spy L well 2340-2680m well section processes and displays result in Ya Bulai area, and wherein, 2648 ~ 2655m section oil reservoir Warning Mark OIL is greater than 0, is designated as oil reservoir.Table 1 is refined spy L well 2345-2665m well section sampling interval is the tables of data of 1m.

Table 1 refined spy L well 2345-2665m well segment data table (sampling interval 1m)

Obviously, those skilled in the art can carry out various change and modification to the present invention and not depart from the spirit and scope of the present invention.Like this, if these amendments of the present invention and modification belong within the scope of the claims in the present invention and equivalent technologies thereof, then the present invention is also intended to comprise these change and modification.

The content be not described in detail in this instructions belongs to the known prior art of professional and technical personnel in the field.

Claims (7)

1. obtained a method for oil reservoir Warning Mark by conventional logging, it is characterized in that: comprise the steps:

Step one, from data file, read conventional logging data;

Step 2, test calculate this area formation parameter;

Step 3, calculate factor of porosity φ according to logging trace;

Step 4, calculating apparant formation water resistivity;

The oil reservoir Warning Mark of step 5, compute depth point;

After step 6, a depth point have calculated, get back to step one, until entire depth section has calculated.

2. the method being obtained oil reservoir Warning Mark by conventional logging according to claim 1, it is characterized in that: in described step one, described conventional logging data comprise: the degree of depth, interval transit time, hole diameter, neutron, density, natural gamma, deep investigation resistivity, shallow investigation resistivity and spontaneous potential.

3. the method being obtained oil reservoir Warning Mark by conventional logging according to claim 2, it is characterized in that: in described step 2, described this area formation parameter comprises: A Erqi cementation factor m, A Erqi constant a, formation water resistivity R _w, apparant formation water resistivity minimum value R _wmn, apparant formation water resistivity maximal value R _wmx, natural gamma ray log value maximal value GR _max, natural gamma ray log value minimum value GR _min, bit diameter BITS.

4. the method being obtained oil reservoir Warning Mark by conventional logging according to claim 3, be is characterized in that: test and calculate formation water resistivity R _wtime, need to carry out temperature correction according to each depth point.

5. the method being obtained oil reservoir Warning Mark by conventional logging according to claim 3 or 4, it is characterized in that: in described step 3, described logging trace comprises interval transit time, neutron and density.

6. the method being obtained oil reservoir Warning Mark by conventional logging according to claim 5, be is characterized in that: in described step 4, described apparant formation water resistivity:

$R_{\mathrm{wa}}=\frac{R_D{\mathrm{\φ}}^m}{a},$

In formula: R _wa-apparant formation water resistivity,

R _d-deep investigation resistivity,

φ-formation porosity,

M-A Erqi cementation exponent,

A-A Erqi constant.

7. the method being obtained oil reservoir Warning Mark by conventional logging according to claim 6, be is characterized in that: in described step 5, the oil reservoir Warning Mark of described depth point:

$\mathrm{OIL}=(\frac{R_{\mathrm{wa}}-R_{\mathrm{wmn}}}{R_{\mathrm{wmx}}-R_{\mathrm{wmn}}}-\frac{\mathrm{GR}-{\mathrm{GR}}_{\min }}{{\mathrm{GR}}_{\max }-{\mathrm{GR}}_{\min }})(1-\frac{\mathrm{CAL}-\mathrm{BITS}}{\mathrm{BITS}}),$

In formula: OIL-oil reservoir Warning Mark,

R _wa-apparant formation water resistivity,

R _wmn-apparant formation water resistivity minimum value,

R _wmx-apparant formation water resistivity maximal value,

GR-natural gamma ray log value,

GR _min-natural gamma ray log value minimum value,

GR _max-natural gamma ray log value maximal value,

CAL-hole diameter,

BITS-bit diameter.