30th IAS MANCHESTER. 2nd - 5th September 2013

Transcription

1 30th IAS MANCHESTER International Association of Sedimentologists The University of Manchester and The City of Manchester are pleased to welcome you to: 30th IAS MEETING OF SEDIMENTOLOGY 2nd - 5th September 2013 Welcome to the 3oth IAS Meeting of Sedimentology, held at the University of Manchester in the United Kingdom, under the auspices of the International Association of Sedimentologists. These proceedings contain all the abstracts of the presentations that appear at the conference. They are arranged in folders by session under 9 themes, namely: Theme 1: Resources Theme 2: Climate and Earth Surface Environments in Deep Time Theme 3: Marine and Coastal Depositional Environments Theme 4: Continental Depositional Environments Theme 5: Basin Analysis Theme 6: Impact of Glacial Processes on Sedimentation Theme 7: Post-Depositional Modification of Clastic and Carbonate Sediments Theme 8: Prediction and Visualization of Sedimentary Processes and Systems Through Modelling Theme 9: Sedimentology at the Biological Interface The Programme Overview provides an outline of when each session will be held during the conference. The abstracts can be viewed by exploring the folders on this USB stick using a file manager. Each abstract has a name that combines the theme and session number, with a prefix to discriminate poster from oral presentations, and finally a number that indicates the run order in the case of oral presentations, or poster board number in the case of poster presentations. e.g., T1S2_P54 = Theme 1, session 2; poster presentation, will be displayed on posterboard location 54. When used in conjunction with the conference handbook it is possible to locate abstracts in the conference abstracts volume and the time an individual presentation will take place. The organisers hope you find these proceedings informative and wish you a very successful conference. CONFERENCE ABSTRACTS VOLUME

2 T1S2_O4 Reservoir Characterization of Mid Main Carbonate (MMC) interval in Cipadati Field (North West Java Basin, Indonesia) to Support Detailed Reservoir Zonation Winardi, S. 1, Toha, B. 1, Suryono, S.S. 1, Prasetya, I. 2 1 Dept of Geological Eng-UGM, Jl. Grafika No 2, Yogyakarta-55281, Indonesia (winards@yahoo.com) 2 PT. Pertamina EP, Jl. Prof. Dr. Satrio No. 164, Jakarta Selatan-12950, Indonesia Generally the MMC is known as a carbonate build up interval in the North West Java Basin, Indonesia, which contains hydrocarbons in some fields such as Rengasdengklok and North Cilamaya. In the Cipadati Field the MMC was drilled by the Explo#1 well and had a thickness of 79 meters. Previously the MMC was assumed to be a homogeneous carbonate reservoir, so petrophysical values gained from the Explo#1 well were used as default values along the entire interval. Further characterization of the MMC is needed to gain a deeper understanding of the heterogeneity of the reservoir including depositional stages, geometry, vertical facies changes, secondary pore types and porosity value. These parameters provided petrophysicists with the information necessary to divide the MMC reservoir into more detailed reservoir zones. The most reliable data to characterize the reservoir is core data, however core is non-continuous through the interval so image logs were used as support data in the non-cored intervals. Well calibration was done using image logs, especially in combination with core, thin sections, cuttings and other log data. Lithological texture could be observed within the image logs, so, based on Dunham limestone classification the lithofacies was identified. Seismic facies analysis, supported by well data, was also conducted to reveal the development of carbonate stages and their geometry during the formation of the MMC. The high resolution of the image log tool provided detailed observation of porosity types greater than 2.5 mm. The reservoir zonation was done based on lithofacies, pore types and porosity value. The result of characterization shows that MMC is not a continuous single homogeneous carbonate but formed in 12 depositional stages. Externally the geometry of the MMC is of a carbonate buildup (classified as a skeletal mound carbonate), but internally the geometry of each stage varies from mound to sheet drape. Overall the MMC was deposited onto the shelf platform. The MMC in this area does not represent a reef build up. Various lithofacies are found ie alternation between wackstone and packstone in lower part and some shale interruption near the top of the interval. Secondary pore types which are observed along interval are vugular (isolated vugs, interconnected vugs, channeling vugs) and fracture porosity (open fracture and partially mineral filled fracture). The result of porosity calculation shows a variation between 5 and 19 percent. Based on its characteristic the reservoir can be divided into 19 zones (11 reservoir zones and 8 nonreservoir zones). Acknowledgements The authors thank to SKK Migas and PT. Pertamina EP for their data support.

3 Reservoir Characterization of Mid Main Carbonate (MMC) Interval in Cipadati Field (North West Java Basin, Indonesia) to Support Detailed Reservoir Zonation By : Winardi, S. 1 Toha, B. 1, Suryono, S.S. 1, Prasetya, I. 2 1 Deptof Geological Eng-UGM, Jl. GrafikaNo 2, Yogyakarta-55281, Indonesia 2 PT. PertaminaEP, Jl. Prof. Dr. SatrioNo. 164,JakartaSelatan-12950, Indonesia winards@yahoo.com September 2013 Outline Geological Background Data & Analysis Result & Discussion Reservoir characteristic of MMC Reservoir zonation Conclusions 2

4 Geological Background CIPADATI MMC MMC (After TT Jabarut 1998 vide Pertamina, 2005) BP study team, EXPLO#1 (Pertamina, 2005) MMC in Explo#1 well was assumed to be a single homogeneous reservoir. Explo#1 Previously, petrophysic analysis used single/same parameter for whole interval. All tested intervals of MMC were water bearing. Carbonate build up (eq MMC) distribution in Rengasdengklok high (Pertamina, 2005) 4

5 Data & Analysis FMI log data from Explo#1 well at MMC interval ( m depth). Composite log data (GR, SP, Resistivity, Density &Neutron). Petrophysic analysis from previous study. Cutting description log Conventional core description at m depth intervals. 14 samples of side wall core description. 5 thin section descriptions. 8 seismic lines across Cipadati field. Other wells data around study area. 5 6

6 Result-1: Reservoir characteristic (Facies, Pore types, Features of subaerial exposure & Depositional stages) Image display of wackestone and packstone facies. packstone wackestone 7 Image display of Shale and Packstone facies. 8

7 Distribution of vertical facies unit of MMC in Explo#1 NO. DEPTH (m) THIKCNESS (m) FACIES Wackestone Serpih ,3 4,3 Packstone ,3-1460,7 0,4 Serpih ,7-1462,5 1,8 Packstone ,5-1462,7 0,2 Serpih , ,6 Packstone ,8 5,5 Wackestone ,8 1510,5 8,7 Packstone ,5 1515,3 4,8 Wackestone ,3 1518,5 3,2 Packstone , ,5 Wackestone 9 Pore Types Vugular porosity types 10

8 vug fracture 11 Feature of subaerial exposure Subaerial exposure example at m High GR reading which is caused by the presence of paleosoil (filled secondary pore), as indicator of subaerial exposure. 4 subaerial exposures are identified along MMC interval, at , 1486, 1495,and mdepth. 12

9 Depositional Stages & Lateral Distribution 13 14

10 Result-2: Detailed Reservoir Zonation ZONES DEPTH (m) THICKNESS (m) FACIES POROSITY TYPES Wackestone Interconnected vug non-reservoar Packstone Open fracture + interconnected vugs non-reservoar Packstone Open fracture + channeling vugs non-reservoar Packstone Interconnected vug non-reservoar Packstone Channeling vug non-reservoar Packstone Partially interconnected vug non-reservoar Wackestone Partly mineral filled fracture + vugs non-reservoar Packstone Interconnected vug Packstone Primer-intergranular Wackestone Interconnected vug Wackestone Open/partially healed fracture + vugs non-reservoar - 15 Relation between porosity types and cementation factor (m) equations Vugular & fossilmoldic porosity, use Nugent (1984) 2(logф s ) m log ф t Vugular & oomoldic porosity, use Nurmi(1984) 2(logф s ) m log ф t Fractures porosity, use Rasmus (1983) Log [ф s3 + ф s2 (1 ф t ) + (ф t -ф s )] m = Log ф t 16

11 Cementation factor (m) of reservoir zones of MMC in Explo#1 NO DEPTH (m) THICKNESS (m) average average Porosity PhiT PhiE Sonic m 17 Re-calculation result of Water Saturation(Sw) of MMC in Explo#1 NO DEPTH (m) THICKNESS (m) PhiE m Rt Rw Sw

12 CONCLUSIONS 1. General reservoir characteristic of MMC in Cipadati Field: Consist of some lithofacies of wackestone, packstone and shales. Had some subaerial exposures, found at , 1486, 1495 and m depth. MMC was formed in12 depositional stages and stage 1, 6, 10, 12are penetrated by Explo#1 well. Both of intergranular primary porosity and secondary porosity types such as vugular (isolated vugs, interconnected vugs, channeling vugs),fractures (open fracture, partially mineral filled/healed fracture)are observed. Some dual porosity of fractures-vugs system also found. 2. MMC is not a single homogeneous reservoir, it consists of nineteen (19) different characteristic zones. Eleven (11) zones are reservoir and eight (8) of them are non-reservoir zones. 19 CONCLUSIONS 3. Reservoir petrophysic properties of MMC; The thickestreservoir is zone1 at m depth with 9.5 m thick and the thinnest one is zone6 at m depth with 0.6 mthick. Highest porosity interval is zone6 at m depth (average PhiE 19 %) and the lowest porosity interval is zone 9 ( m depth) and zone 10 ( mdepth) with average PhiE of both isjust 5 %. The highest value of cementaion factor (m) is 2.59 found at packstone facies in zone 6 and the lowest one is 1.31 found at wackestone facies in zone10. Overall, re-calculation of Sw (water saturation) value in each detailed reservoir zones using new different cementation factor (m) approach, based on pore types, show high value of Sw about 93%-99% and this resut is more accurate according to the well testing result in Explo#1 well that clearly prooved water bearing for all intervals. 20