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The velocity configuration performance

As a result of the held seismic observations complete enough submissions about features of rate of propagations longitudinal and transverse waves are received.
Allocation of mean velocities of the pointed types of surges in a vertical cut-away profiles VmeanP=f(H) and VmeanS=f(H) (Pics. 4.8 & 4.9), being transform time-depth curves To=f(H), introduced in the report in plot and tabular forms (the text appendix №1). Functional link of times of run of surges and depths in this table is produced for two reference levels: a daylight area and an absolute zero (a.0.).
By consideration of profiles of mean velocities it is possible to see that values of rate of propagations in environment both longitudinal, and transverse waves monotonously increase with depth with rather gentle reduction of a high-speed gradient. So for longitudinal waves accretion VV mean on 100m a vertical profile in cut-away top compounds ~ 50m/s, and in bottom ~ 25m/s. The similar oilpainting of allocation ΔVmean=f(H) is characteristic and for transverse waves (accretions VmeanS  on 100m a profile in spacings corresponding to longitudinal waves compound 30m/s & 15m/s). Magnitudes of mean velocities of propagation longitudinal and transverse waves grow with depth from 1650m/s to 2450m/s and from 270m/s to 900m/s accordingly.

At forming of sheet high-speed model for breakdown on benches we use first-arrival curves of a straight line longitudinal and refraction the surges fixed with removed Shot2. Primary arrivals of these surges produce exclusively distinct picture of high-speed differentiation in cut-away top (fig. 4.10) at the expense of the refraction most expressed in this spacing. This differentiation is pointed out not only frequent fatigue failures of a hodograph refraction surges, but also multiple reflexes of longitudinal and incidenting alternating waves from shallowly lying down boundaries. As a result of the held analysis in a hole cut-away 17 high-speed layers are dedicated. It is necessary to notice that above-jig a cut-away part (the spacing 0-230m) in connection with total absence of primary arrivals 'does not participate' in layer-speed model. In the generated model gradual magnification of layer velocities with depth is marked: On longitudinal waves from 1660m/s in maiden below- jig a bench, to 4500m/s in the spacing uncovered by a hole above-Jura the foundation;; on transverse waves for the same spacings of a cut-away from 520m/s to 2400m/s. Relative differences of sheet velocities of both types of surges, basically, coincide.

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velocity 3

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

The enhanced differences of velocities are observed on boundary of 16-17 layers that is pointed out also by generation of intensive reflexes longitudinal and alternating waves (fig. 4.10). Growth of sheet velocities in this spacing is caused, obviously, influencing of fundamental rocks.
            'Failure' Vlayer Vla is referred to other feature of plastovo-speed model in a depth interval 2200-2370m that we presumptively link to a mudding of bottoms kulumzinsk suites.
Average values of complex argument γ=Vs/Vp, functionally linked to a Poisson's ratio, as it is possible to see it on a drawing γcp=f(H) (fig. 4.9), continuously increase from 0,23 to 0,4. The role of this argument is reduced to use at calculation of abscisses of reflexion points at time section constructing on exchange back waves.
On a first-arrival curve of a forward longitudinal wave (ПВ1) interval velocities with a pitch of observations, i.e. 10m have been instituted. Profile Vint=f(H) has accurately expressed oscillating nature against communal increase VintP with depth (fig. 4.9). The form of a background with enough significant extent of approach is supervised by the form of the profile of sheet velocities. The magnitude of the oscillation amplitude of the curve Vint=f(H) is characterised by rather gentle differentiation: magnitudes of spans vary in limits ±100 m/s.
From all stated follows that again received at VSP the data completely has provided definition envisioned the geological task high-speed arguments and by that has allowed to compound submission about features of a velocity configuration.



The performance and seismogeological interpretation time and depth profiles VSP on longitudinal and exchange back waves

            At the treating final stage constructing time and depth profiles on longitudinal and exchange back waves in the area of hard currency is held. - Shot2. In connection with more (approximately twice) length the cut-away on longitudinal waves bears the greatest information on features of a geological feature on the pointed line.

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On this cut-away the basic reflexion horizons Ф2 (a surface to Jura the foundation), IIa base surface bazhen suites), III (bottoms pokursk suites) are continuously traced. Reflexes in depositions kulomzin, tarsk, kiyalinsk suites have the extremely unstable nature, are traced in the form of fragmentary lines of correlation, shaped arched lines. Instability and it is is gentle the expressed peak level of these reflexes it is possible to see as well on time section on a profile driving in immediate proximity from a hole (fig. 4.12) that, it is obviously linked to unevenness of lithological composition of depositions of these suites.
From the enumerated dominating reflexes by the steadiest under the form and peak expressiveness horizon IIa. is. In the hypsometric relation horizon IIa tests smooth submergence with a mean time gradient 0.0035s on 100m a horizontal profile, the plutonic gradient compounds nearby 2m/100m. Lying down directly under light-duty georgievsk suite sand formations U11 and U12 a percarbonic member are in position of the extremely astable wave pattern introduced two is is gentle expressed on amplitude and interfering among themselves lines of correlation. Such nature of a wave pattern with enough big fraction of confidence can be linked to unevenness of lithological composition and bed thickness U11 and U12.
            Unstable nature of a wave field is observed and in the range of depositions of the Tyumen suite characterised by essentially abbreviated power. In this spacing is not present it is peak expressed and traced on all length of a profile of lines of correlation.
            Spreading depositions of the Tyumen suite the surface to Jurassic the bases generates was gentle intensive reflex F2. Such nature of reflex is caused by absence on a surface of the foundation of acoustically contrast boundary.
Below reflex F2 with a time gap nearby 0.035s it is dedicated high voltage the reflex indexed by letter F1 and stratified by us with a base surface of a zone of desintegration of formations of the Paleozoic foundation. This reflex characterised by so high peak expressiveness, is traced and on cut-away CMP (fig. 4.12). It is necessary to notice that the dedicated zone can introduce trial concern if to allow that according to LOG it is valued as a spacing with not clear nature of saturation [10].

Both reflexion horizons F2 and F1 also as well as horizon IIa test submergence aside ПВ2. However, unlike horizon IIa, their background of the monoclinalо

submergences it is complicated by peephole structural forms of type of a bending flexure (Rsv-Rsv 150-350) and an anticlinal bend (Rsv-Rsv 350-550).
On nature of a wave pattern on a lease of the Rsv-Rsv 610-540 we dedicate banding zone of the tectonic disturbances amazing formations of a zone of desintegration, deposition Tyumen and Bazhen suites. The odds of infiltration of a zone hill up on a cut-away is quite real up to depositions of the upper chalk and paleogene. It is necessary to notice that according to seismic survey CMP 3D wide progressing of a shearing in a jacket of the Western-Siberian table, in particular in northern areas of the Tyumen region, in Shirotnom Priobe, on declines and periclinal leases of the Aleksandrovsky megaarbor (Tomsk region) is revealed. G.N.Gogonenkov and A.I.Timurziev link these disjunctive dislocatings with young - a neogene-chetvertichnymi flaw faults in the Paleozoic foundation of Western Siberia.
On fig. 4.13 both 4.14 are demonstrated time and depth profiles on longitudinal and exchange back waves. Apparently, they are quite well compared among themselves.

However because of the depressed quality of a cut-away on alternating waves we did not hold definition of a Poisson's ratio.

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"Learning of an energy absorption of seismic transients"