Coring and its types

PRESENTED BY ADNAN ZADA

1. Presentation petrophysics TOPIC : CORING AND ITS TYPES

2. PRESENTED BY: ADNAN ZADA (03) USMAN ALI (48) WAQAS NADEEM (52) WAQAR ALI (51) ISRAR AHMAD (17) YOUSAF KHAN (33)

3. AGENDA CORING PURPOSE OF CORING TYPES OF CORING 1 CONVENTIONAL CORING 2 SIDE WALL CORING DIFFERENCE BETWEEN CONVENTIONAL AND SIDE WALL CORING

4. WHAT IS CORING Cores which extract from the formation /reservoir using special coring tools. once the cores is cut ,they are captured and retrieved to the surface for analysis of different physical parameters A core sample is a cylindrical section of (usually) a naturally occurring substance. Most core samples are obtained by drilling with special drills into the substance, for example sediment or rock, with a hollow steel tube called core drill. The hole made for the core sample is called the "core bowling". A variety of core samplers exist to sample different media under different conditions. More continue to be invented on a regular basis.

5. continue In the coring process, the sample is pushed more or less intact into the tube. Removed from the tube in the laboratory, it is inspected and analyzed by different techniques and equipment depending on the type of data desired

6. Purpose of coring The purpose of getting cores is to obtained rock samples of sufficient size for : `1 making reservoir analysis test to determined porosity, permeability ,residual oil and water saturation( primery purpose of coring).. To establish the physical character of formation boundry .. To furnish paleontological data for age and facies correlation To determined the structural attitude of the beds

7. Types of coring There are two types of coring which are 1 conventional coring 2 side wall coring

8. Conventional coring Conventional coring is a methed of drilling and acquiring rock samples to retrieve the core samples ..the complete rod string and core barrel has to be removed from the hole When the bit is about to enter a formation of special interest .a service company may be brought in to take barrel cores. The coring tools consist of an annular diameter bit to cut the core and a hollow barrel to catch it

9. continue Core samples may be of any length .but cores of over 90 feet are hard to handle. A 60 feet core is average cores ,which can be handle easily.. A core diameter range from 11/8 to 5 inches with 4 inches being the most popular size for core analysis Since it is costly and time consuming ,also removing the cores is some time dangrous .since it is possible to swab the well and cause a blowout. So sidewall coring is most commonly used than conventional coring

10. Side wall coring Side wall coring is a methed used in zones where core recovery by conventional methed was less than expected or wheres cores were not obtained as drilling progressed Side wall coring is useful in paleontological work ,for it is possible to get shale samples micropaleo analysis at definite depth A side wall coring device is lowered into the hole on a wire line cable and a sample of the formation is taken at the desire depth .

11. continue This done by shooting a hollow bullet into the bore hole wall, then pulling it out of the well and bring up to the surface.. There are as many as thirty bullets per guns and since two guns can be used .. Up to sixty cores can be obtained during one run. If electric logs have been run prevously , a spontanous potential or gamma ray curve is used to determined gun position by direct log correlation

12. DIFFERENCE BETWEEN CONVENTIONAL AND SIDE WALL CORING Conventional coring: 1 Conventional coring provides large samples It is more better and more consistent representation of formation.. It is better for heterogenous rocks or for more complex lithologies … SIDE WALL CORE : Side wall coring provides smaller samples It is less representative of heterogenous formation..

13. 3 within 1 to 2 percent of whole cores for medium to high porosity formation

14. THANK YOU