AASPI Seismic interpretation of ree Sand channels on the ...

Seismic interpretation of Cree Sand channels on the Scotian Shelf Rustam Khoudaiberdiev, Craig Bennett, Paritosh Bhatnagar, and Sumit Verma*

The University of Texas of the Permian Basin

Potential reservoirs can be found within deltaic channels, these

channels have the ability to form continuous transport systems for

hydrocarbons. Distributary sand-filled channels in particular can serve

as excellent reservoirs. The emphasis of this study is taking a detailed

look into the sand channels within the Cree Sand of the Logan Canyon,

as well as using coherence and coherent energy seismic attributes to

delineate these features. Extensive studies have been performed in

analysis of deltaic channel systems and their ability to act as reservoirs

for hydrocarbons. The paper will follow an equivalent approach,

employing 3D seismic survey data and seismic interpretation techniques

to identify and map sand channels. The study area is focused on the

Penobscot field, located off of the eastern shores of Nova Scotia.

ABSTRACT

AASPI software was used to compute seismic attributes. Petrel (Schlumberger) was used for seismic interpretation. Nova Scotia

Department of Energy for keeping the Penobscot 3D seismic survey data open source. For questions, please email

[email protected]

GEOLOGY OF THE STUDY AREA

ACKNOWLEDGEMENTS

Figure 1(a). Location map of the

study area (Google Earth Maps).

The Penobscot 3D seismic sur-

vey is displayed in the yellow rec-

tangle.

Figure 2. Stratigraphic column

of the study area. The first

track indicates measured

depth. The second track

shows the gamma ray log for

well L-30, the darker color sig-

nifies high gamma ray values,

which indicates shaly facies,

whereas the light colors are for

low gamma ray values, indi-

cating sand rich facies. The

third track shows the name of

the formation and geological

age (modified from Bhatnagar

et al., 2017).

SEISMIC ATTRIBUTE STUDY

Figure 3. (a) Time structure

map of Petrel top surface, Well

L-30 shown as a green dot in

Figure 3a. (b) Seismic ampli-

tude section through AA’.

Gamma ray log from the L-30 well is posted on seismic to indicate the sandy

and shaly lithology (see Figure 2 for color scale). Annotations on the right

hand side indicate the name of the formation tops (in black regular font) and

their ages (in light blue italics font).

Figure 4. Channel delineation with the help of seismic attributes. In left (a, c and e) seismic amplitude on

the vertical sections (same color bar as Figure 3b), and coherent energy on a stratal slice. In right (b, d, f)

coherence stratal slices. This figure shows three levels of channels, from deepest (a and d) to shallowest (e

and f). For clarity, we indicate these stratal slices as levels I, II and III. Notice that the deepest stratal slice,

Level I (a and b, at stratal slice 614 ms below Petrel) shows relatively thin channels. Whereas at the shal-

lower Level II (c and d, at stratal slice 490 ms below Petrel) contain broader channels, and the shallowest

Level III (e and f, at stratal slice 430 ms below Petrel) shows even broader channels.

CONCLUSIONS

Figure 5. Interpretation of

the deltaic channels based

on the seismic attribute in-

terpretation. (a) sea level

curve, obtained from Haq

et al, 1987. (b-d) the

changing position of the

delta due to sea level,

from older to younger.

Here, this model is bound-

ed by the orange rectangle

shown in the Figure 1. The

dashed line represents the

Aptian paleo shelf break.

Bhatnagar, P., C. Bennett, R. Khoudaiberdiev, S. Lepard and S. Verma, 2017, Seismic attribute illumination of a synthetic transfer zone: submitted for 87th Annual International Meeting , SEG Expanded Abstracts.

Google Earth Maps, https://www.google.com/earth/, browsed on March 15, 2017.

Haq, B.U., J. Hardenbol, and P.R. Vail, 1987, Chronology of fluctuating sea levels since the Triassic: Science, 235, 1156-1187.

REFERENCES

COHERENCE AND COHERENT ENERGY ATTRIBUTES

AASPI