Casing While Drilling Level 2 as Mitigation for Shallow Gas and Loss Circulation Hazards in Surface Section

2021 ◽  
Author(s):  
Nuring Tyas Wicaksono ◽  
Hanafi Muhamad Falhum ◽  
Agung Subagio ◽  
Radianto Ritamawan ◽  
Andaru Ibnu Pratomo ◽  
...  
Keyword(s):  
Shallow Gas ◽  
New Approach ◽  
Pilot Hole ◽  
East Kalimantan ◽  
Surface Section ◽  
Level 2

Abstract Casing while drilling Level 2 was introduced to mitigate problems in the surface section of Mutiara and Pamaguan Field in East Kalimantan. These two fields have historical shallow gas and loss circulation hazards in surface section. Following a blowout incident in Pamaguan in 2012, new policy was introduced for drilling the surface section in Mutiara and Pamaguan. A pilot hole must be drilled, and additional surface casing shall be set. Although considered safe, longer drilling days and vulnerability to repeated loss circulation made this method inefficient. A new approach to mitigate the problem was proposed by introducing casing while drilling Level 2 in 2020 drilling campaign. Many papers already discussed about the effectiveness of casing while drilling to mitigate loss circulation. However, a limited number of papers discuss casing while drilling to mitigate shallow gas. Costeno et al, 2012, discussed the use of casing while drilling to mitigate shallow gas. However, the risk of shallow gas was low and there was no shallow gas record during the execution. This paper specifically discusses about utilizing casing while drilling (CWD) technology to mitigate not only loss circulation, but also shallow gas risks during surface hole interval. Both hazards occurred in several wells during job execution and CWD with its plastering effect has managed to drill troublesome surface hole safely, thus making it the better alternative to achieve efficient drilling in comparison with the previously used pilot hole method.

First Application Drilling New Wells with HWU in Swamp Environment, Mahakam Delta

2021 ◽  
Author(s):  
R. A. S Wijaya
Keyword(s):  
Drilling Rate ◽  
Shallow Gas ◽  
Field Development ◽  
Drilling Rig ◽  
East Kalimantan ◽  
Well Location ◽  
Shallow Wells ◽  
Drilling Unit ◽  
Mature Field ◽  
Mahakam Delta

Tunu is a mature giant gas and condensate field locate in Swamp Area on Mahakam Delta, East Kalimantan, Indonesia. The field has been in developed for more than 40 years and considered as a mature field. As mature field, finding an economic well has become more challenging nowadays. The deeper zone of Tunu (TMZ) has no longer been considered profitable to be produced and the focus is shifted more on the producing widespread shallow gas pocket located in the much shallower zone of Tunu (TSZ). Facing the challenge of marginal reserves in the mature field, Pertamina Hulu Mahakam (PHM) take two approaches of reducing well cost thus increase well economics, improving drilling efficiency and alternative drilling means. Continues improvement on drilling efficiency by batch drilling, maxi drill, maximizing offline activities and industrialization of one phase well architecture has significantly squeezed the well duration. The last achievement is completing shallow well in 2.125 days from average of 6.5 days in period of 2017-2019. Utilization of Swamp Barge Drilling Rig on swamp area had been started from the beginning of the field development in 1980. Having both lighter and smaller drilling unit as alternative drilling means will give opportunity of reducing daily drilling rate. Hydraulic Workover Unit (HWU) comes as the best alternative drilling means for swamp area. In addition, fewer and smaller footprint equipment requires smaller barges with purpose of less civil works to dredge the river and preparing well location. Drilling with HWU project has been implemented at Tunu area with 5 wells has been completed successfully and safely. HWU drilling concept considered as proven alternative drilling means for the future of shallow wells development.

One Phase Well OPW : Unlock Shallow Reservoir Efficient and Economically by Eliminating Surface Casing

2021 ◽  
Author(s):  
Irfan Hanif ◽  
Bramarandhito Sayogyo ◽  
R Riko ◽  
Praja Hadistira ◽  
Karina Sari
Keyword(s):  
Shallow Gas ◽  
Two Phase ◽  
East Kalimantan ◽  
Drilling Operations ◽  
The Common ◽  
Mature Field ◽  
The Cost ◽  
Mahakam Delta ◽  
Common Architecture ◽  
Drilling Time

Abstract Tunu is a mature giant gas and condensate field locate in Mahakam Delta, East Kalimantan, Indonesia. The field has been in development for almost 30 years and currently has been considered as a mature field where to put a state of an economic well has become more challenging nowadays. The deeper zone of Tunu has no longer been considered as profitable to be produced and the current focus is more on the widespread shallow gas pocket located in the much shallower zone of Tunu. One phase well is architecture without 9-5/8" surface casing. OPW is one-section drilling using a diverter mode from surface to TD without using BOP. Historical for OPW is began from 2018, where drilling reservoir section using diverter mode in two-phase. In 2018 also succeeded in performing perforated surface casing. Due successfully in drilling operation using diverter and perforated surface casing, in 2019 drilling trials for OPW were carried out. Until now, the OPW architecture has become one of the common architecture used in drilling operations as an optimization effort. Until December 2020 PHM has completed 15+ OPW wells. A general comparison of OPW and SLA well is at the cost of constructing a well of approximately 200,000 - 300,000 US$. The disadvantages of OPW wells are more expensive in the mud and cement section when using a 9-1/2" hole, but in terms of the duration, OPW drilling time is more efficient up to 2-3 days. If viewed from the integrity of the OPW wells, from 15 OPW wells that have been completed, only 2 of them have SCP.

scholarly journals INDIKASI GAS BIOGENIK DI PERAIRAN DELTA MAHAKAM, PROVINSI KALIMANTAN TIMUR

2017 ◽  
Vol 14 (2) ◽  
Author(s):  
I Nyoman Astawa ◽  
Deny Setiady ◽  
Priatin Hadi Wijaya ◽  
GM. Hermansyah ◽  
Mario Dwi Saputra
Keyword(s):  
Sedimentation Rate ◽  
Methanogenic Bacteria ◽  
Laboratory Analysis ◽  
Shallow Gas ◽  
Biogenic Gas ◽  
Methane Gas ◽  
East Kalimantan ◽  
High Sedimentation ◽  
Mahakam Delta ◽  
Very High

Gas biogenik dikenal sebagai gas rawa atau gas dangkal yang terbentuk dari bakteri metanogenik pada lingkungan anaerobik, khususnya pada daerah-daerah yang tingkat sedimentasinya sangat tinggi.Tujuan penelitian untuk mengetahui secara lebih rinci akan keberadaan gas tersebut di Delta Mahakam. Sungai tersebut merupakan sungai terbesar dan terpanjang di wilayah Kalimantan Timur dan mempunyai tingkat sedimentasi sangat tinggi. Daerah tersebut sangat cocok untuk penelitian indikasi gas biogenik. Hasil penelitian ditandai dengan terdapatnya kantong gas pada rekaman strata box, yang berada pada kedalaman lebih dari 10 (sepuluh) meter. Berdasarkan analisis laboratorium terhadap sampel gas yang diambil di bekas lubang bor adalah gas metan.Kata kunci: rekaman strata box, gas metan, Delta MahakamBiogenic gas known as swamp gas or shallow gas formed by methanogenic bacteria in anaerobic environments, especially in areas that the sedimentation rate is very high. The objective of the research is to find out more detail the occurrence of gas in the Mahakam Delta. The river is the largest and longest river in the East Kalimantan, and it has a very high sedimentation rate.  This area is very good to study the indication of the biogenic gas. The result is signed by gas pocket in the strata box records, whereas at a depth of more than 10 (ten) meters. Based on the laboratory analysis of the samples taken from the former gas borehole is a methane gas.Keywords: strata box records, methane gas, Mahakam Delta.

Machine Learning Technology to Improve Precision and Accelerate Screening Shallow Gas Potentials in Tunu Shallow Gas Zone, PT Pertamina Hulu Mahakam

2021 ◽  
Author(s):  
R. Herbet
Keyword(s):  
Machine Learning ◽  
Learning Technology ◽  
Gas Reservoirs ◽  
Shallow Gas ◽  
Gas Field ◽  
East Kalimantan ◽  
Main Challenge ◽  
Shallow Zone ◽  
Learning Probability ◽  
Mahakam Delta

Tunu is a giant gas field located in the present-day Mahakam Delta, East Kalimantan, Indonesia. Tunu gas produced from Tunu Main Zone (TMZ), between 2500-4500 m TVDSS and Tunu Shallow Zone (TSZ) located on depth 600 - 1500 m TVDSS. Gas reservoirs are scattered along the Tunu Field and corresponds with fluio-deltaic series. Main lithologies are shale, sand, and coal layers. Shallow gas trapping system is a combination of stratigraphic features, and geological structures. The TSZ development relies heavily on the use seismic to assess and identify gas sand reservoirs as drilling targets. The main challenge for conventional use of seismic is differentiating the gas sands from the coal layers. Gas sands are identified by an established seismic workflow that comprises of four different analysis on pre-stack and angle stacks, CDP gathers, amplitude versus angle(AVA), and inversion/litho-seismic cube. This workflow has a high success rate in identifying gas, but requires a lot of time to assess the prospect. The challenge is to assess more than 20,000 shallow objects in TSZ, it is important to have a faster and more efficient workflow to speed up the development phase. The aim of this study is to evaluate the robustness of machine learning to quantify seismic objects/geobodies to be gas reservoirs. We tested various machine learning methods to fit learn geological Tunu characteristic to the seismic data. The training result shows that a gas sand geobody can be predicted using combination of AVA gather, sub-stacks and seismic attributes with model precision of 80%. Two blind wells tests showed precision more than 95% while other final set tests are under evaluated. Detectability here is the ability of machine learning to predicted the actual gas reservoir as compared to the number of gas reservoirs found in that particular wells test. Outcome from this study is expected to accelerate gas assessment workflow in the near future using the machine learning probability cube, with more optimized and quantitative workflow by showing its predictive value in each anomaly.

One Phase Well (OPW): Unlock Shallow Reservoir Efficiently and Economically ay Eliminating Surface Casing

2021 ◽  
Author(s):  
I. Hanif
Keyword(s):  
Oil Well ◽  
Shallow Gas ◽  
Two Phase ◽  
Drilling Operation ◽  
East Kalimantan ◽  
Drilling Operations ◽  
Mature Field ◽  
The Cost ◽  
Mahakam Delta ◽  
Drilling Time

Tunu is a mature giant gas and condensate field locates in Mahakam Delta, East Kalimantan, Indonesia. The area has been developed for almost 30 years and is currently considered a mature field, where putting a state of an economical oil well has become more challenging nowadays. The deeper zone of Tunu has no longer been considered profitable to be produced. The current focus is more on the widespread shallow gas pocket located in the much more external area of Tunu. One phase well is architecture without 9-5/8" surface casing. OPW is one-section drilling using a diverter mode from surface to TD without using BOP. Historical for OPW is began from 2018, where drilling reservoir section using diverter mode in two-phase. In 2018 also succeeded in performing perforated surface casing. Due to a successful drilling operation using diverter and perforated surface casing in 2019, drilling trials for OPW were carried out. The OPW architecture has become one of the standard architectures used in drilling operations as an optimization effort. Until December 2020, PHM* has completed 15+ OPW wells. A general comparison of OPW and SLA well is at the cost of constructing a well of approximately 200,000 - 300,000 US$. The disadvantages of OPW wells are more expensive in the mud and cement section when using a 9-1/2" hole. But, OPW drilling time is more efficient in terms of the duration, up to 2-3 days. Based on the integrity of the OPW wells, from 15 OPW wells that have been completed, only 2 have SCP.

Unification of the "Burst" and "Linear" Theories of Periodontal Disease Progression: A Multilevel Manifestation of the Same Phenomenon

2003 ◽  
Vol 82 (3) ◽  
pp. 200-205 ◽  
Author(s):  
M.S. Gilthorpe ◽  
A.T. Zamzuri ◽  
G.S. Griffiths ◽  
I.H. Maddick ◽  
K.A. Eaton ◽  
...  
Keyword(s):  
Periodontal Disease ◽  
Disease Progression ◽  
Repeated Measures ◽  
Regression To The Mean ◽  
Random Coefficient Models ◽  
Linear Change ◽  
New Approach ◽  
Level 3 ◽  
The Mean ◽  
Level 2

Previously, burst and linear theories for periodontal disease progression were proposed based on different but limited statistical methods of analysis. Multilevel modeling provides a new approach, yielding a more comprehensive model. Random coefficient models were used to analyze longitudinal periodontal data consisting of repeated measures (level 1), sites (level 2), teeth (level 3), and subjects (level 4). Large negative and highly significant correlations between random linear and quadratic time coefficients indicated that subjects and teeth with greater-than-average linear change experienced decelerated variation. Conversely, subjects and teeth with less-than-average linear change experienced accelerated variation. Change therefore exhibited a dynamic regression to the mean at the tooth and subject levels. Since no equilibrium was attained throughout the study, changes were cyclical. When considered as a multilevel system, the "linear" and "burst" theories of periodontal disease progression are a manifestation of the same phenomenon: Some sites improve while others progress, in a cyclical manner.

scholarly journals EVALUASI KAPABILITAS AUDIT INTERNAL PADA PERWAKILAN BPKP PROVINSI KALIMANTAN TIMUR

2018 ◽  
Vol 2 (1) ◽  
pp. 59
Author(s):  
Imam Nazarudin Latief
Keyword(s):  
Performance Management ◽  
Internal Audit ◽  
Field Research ◽  
Governance Structure ◽  
East Kalimantan ◽  
Organizational Relations ◽  
Level 3 ◽  
Capacity Improvement ◽  
And Performance ◽  
Level 2

This study aims to determine (1) To know the understanding of the enhancement of APIP capability by using Internal Audit Capability Model (IA-CM) (2) To know the internal audit capability level at the BPKP Representative of East Kalimantan Province and the efforts to be taken to improve and maintain it. This research was conducted at BPKP Representative of East Kalimantan Province. Period assessed by the author's internal audit capability is the period of 2016.This research is conducted by field research and literature research by reading the literature related to the problem under study. The data used to evaluate internal audit capability at BPKP Representative of East Kalimantan Province is data of internal audit capability condition of BPKP Representative of East Kalimantan Province. The analytical tool used in this research is Head of BPKP Regulation No. 16 of 2015 on Technical Guidelines for Capacity Improvement of Government Internal Supervisory Apparatus.The result of this research is internal audit capability of BPKP Representative of East Kalimantan Province on elements of Role and Service, Professional Practice, Accountability and Performance Management, Organizational Relations and Culture, The Governance Structure is at level 3 (integrated), while the element of Human Resource Management is at level 2 (infrastructure). Based on the evaluation of the six elements, the internal audit capability of BPKP Representative of East Kalimantan Province is at level 3 (integrated) with the record.

Shallow Gas Identification using LWD Monopole Sonic: A-non Radioactive for Safe and Effective Logs Acquisition in Tunu Field, Mahakam Delta

2020 ◽  
Author(s):  
A.T. Santoso
Keyword(s):  
Oil And Gas ◽  
Neutron Density ◽  
Shallow Gas ◽  
Gas Field ◽  
Safety Issues ◽  
East Kalimantan ◽  
Main Challenge ◽  
Gas Identification ◽  
Fluid Interpretation ◽  
Mahakam Delta

The Tunu field is a swamp giant gas field located in the Mahakam Delta, East Kalimantan. Stratigraphically, this field has an anticline structure with three main intervals; Tunu Shallow Zone (TSZ), Fresh Water Zone (FWZ), and Tunu Main Zone (TMZ). Shallow gas reservoirs of TSZ have been produced since 2008, following the production of TMZ in the 1990s. Drilling targets in the shallow gas reservoir decreased significantly due to limited reservoir targets, high inclination wells and a low oil price environment. The utilization of radioactive source logging (density and neutron) on Logging While Drilling (LWD) tools is not recommended to be performed in open hole mode for operational and safety issues (e.g: tool stuck). Thus, LWD Monopole sonic is chosen as a replacement of LWD Neutron-Density logs and helps to differentiate between shallow gas potential and coal lithology which is the main challenge in TSZ at interval depth above 1200 mSS. The methodology utilized sonic semblance (STRA) and compressional slowness (DTc) data at real-time and memory data logs, so early decision can be made in drilling mode. In a gas-bearing reservoir, both semblance and slowness are missing, while in coal it produced strong semblance. In order to differentiate carbonate lithology, additional data, such as cutting, calcimetry, drilling Rate of Penetration and Gas While Drilling are utilized. During 2018-2020, 5 wells have been drilled using LWD Monopole sonic together with LWD GR-Resistivity-Neutron-Density (Triple Combo) to calibrate the fluid interpretation and 3 trial wells with only GR-Resistivity-Monopole Sonic. As a result, LWD Monopole sonic is able to differentiate between Gas and Coal based on semblance and slowness with a success ratio up to 80%. This LWD Monopole Sonic provides a non-radioactive solution for safe and effective logs acquisition for shallow gas identification that could be applied in oil and gas fields outside Mahakam.

A new approach to achieve high-precision depth prediction for underlying reservoir of shallow gas: A case study from Bohai Bay, China

2016 ◽  
Author(s):  
Jianhui Liu ◽  
Tongxing Xia ◽  
Xuefeng Zhou ◽  
Xuetong Liu ◽  
Donghong Zhou ◽  
...  
Keyword(s):  
High Precision ◽  
Bohai Bay ◽  
Shallow Gas ◽  
New Approach ◽  
Depth Prediction
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