Penentuan parameter-parameter untuk menentukan isi awal minyak ditempat secara volumetrik pada reservoir x.
P Penentuan reservoir X dengan memiliki 73 sumur dengan total sumur penghasil 24 sumur, sumur injeksi 6 sumur, sumur kering 4 sumur, dan sumur yang ditutup 39 sumur. Dari 73 sumur akan dihitung nilai saturasi pada 8 sumur yang dinilai sudah mempresentasikan dari beberapa sumur lainnya. Sumur-sumur tersebut antara lain RF-1, RF-2, RF-3, RF-4, RF-5, RF-6, RF-7,RF-8 dan reservoir yang dipilih pada lapangan X adalah reservoir A dan reservoir B. Reservoir tersebut dipilih berdasarkan remaining reserve yang dinilai masih besar. Cara perhitungan saturasi reservoir A dan reservoir B dilakukan dengan menentukan beberapa parameter seperti Vshale, Rt, Rw, dan porositas, dimana hasil Vshale rata-rata struktur A pada RF-1 sebesar 67.62 %, RF-2 sebesar 34.39 %, RF-3 sebesar 45.36 %, RF-4 sebesar 35.90%, RF-5 sebesar 36.54 %, RF-6 sebesar 65.76 %, RF-7 sebesar 52.01 %, dan RF-8 sebesar 35.35%. Pada struktur B memiliki nilai volume shale rata-rata sebesar RF-1 sebesar 53.67 %, RF-2 sebesar 26.36 %, RF-3 sebesar 47.36 %, RF-4 sebesar 16.06 %, RF-5 sebesar 20.56 %, RF-6 sebesar 41.46 %, RF-7 sebesar 40.37 %, dan RF-8 sebesar 26.85 %, penilaian true resistivity (Rt) dimana cara perhitungannya adalah dengan melihat grafik ILD pada track 2 triple combo log, penentuan resistivitas air formasi (Rw). Penentuan resistivitas air formasi pada tiap-tiap sumur menggunakan metode picket plot, dimana hasil Rw pada lapisan A sebesar 0.8 ohmm dan lapisan B sebesar 1.54 ohmm, dan porositas efektif pada tiap sumur di zona yang dianalisis dengan melihat Isoporosity map didapatkan nilai porositas efektif lapisan A memiliki nilai rata-rata porositas adalah 16.1658 % dan Peta porositas efektif lapisan B memiliki nilai rata- rata porositas adalah 27.3521 %.. Setelah parameter-parameter tersebut didapatkan maka penentuan saturasi air bisa dihitung dengan metode formula Archie, Indonesia, dan Simandoux. Kemudian didapatkan hasil rata-rata saturasi air dengan metode archie lapisan A sebesar 80.57 % dan lapisan B sebesar 55.03 %. Perhitungan saturasi air rata-rata dengan menggunakan metode Indonesia didapatkan hasil lapisan A sebesar 34.3627 % dan lapisan B sebesar 28.236 %. Perhitungan saturasi air rata-rata dengan menggunakan metode Simandoux didapatkan hasil lapisan A sebesar 22.0805 % dan lapisan B sebesar 8.255% dan ditentukan metode mana yang dipilih untuk reservoir A dan reservoir B. Cadangan reservoir A dan B dihitung berdasarkan metode volumetrik dengan volume bulk reservoir A sebesar 23333.69 Acre ft dan volume bulk reservoir B sebesar 37854.49 Acre ft, saturasi air reservoir menggunakan metode Indonesia pada reservoir A sebesar 34.3627 % dan saturasi air reservoir B sebesar 28.236 %, faktor volume formasi minyak awal (Boi) sebesar 1.0531 BBL/STB adalah sebesar 13.1211 MMSTB pada reservoir A dan 40.2064 MMSTB pada reservoir B.
T The X reservoir determination by having 73 wells with a total of 24 wells, injection wells, 6 wells, 4 wells dry wells, and a well-sealed wells 39 wells. From 73 wells will be calculated saturation value at 8 wells that are judged to have already presented from some other wells. The wells include RF-1, RF-2, RF-3, RF-4, RF-5, RF-6, RF-7, RF-8 and selected reservoirs on field X is Reservoir A and Reservoir B. The Reservoir is chosen based on the remaining reserve which is still great. How to calculate reservoir saturation A and reservoir B is done by specifying several parameters such as Vshale, Rt, Rw, and porosity, where the results of the average Vshale of structure A on RF-1 amounted to 67.62%, RF-2 by 34.39%, RF-3 by 45.36%, RF-4, amounting to 35.90%, RF-5 of 36.54%, RF-6 for 65.76%, RF-7 amounted to 52.01%, and RF-8 amounted to 35.35%. In structure B has an average shale volume value of RF-1 of 53.67%, RF-2 of 26.36%, RF-3 of 47.36%, RF-4 of 16.06%, RF-5 of 20.56%, RF-6 of 41.46%, RF-7 of 40.37%, and RF-8 of 26.85%, assessment of true resistivity (RT) where the calculation way is to look at the ILD graph on the track 2 triple combo log, determining the resistivity of the formation water (Rw). Determining the resistivity of the formation water in each well using A plot picket method, in which the result of Rw at layer A of 0.8 ohmm and layer B amounted to 1.54 ohmm, and the porosity effective at each well in the zone analyzed by viewing the Isoporosity map Obtained the value of effective porosity layer A has the average value of porosity is 16.1658% and the map of effective porosity layer B has the average value of porosity is 27.3521%. Once these parameters are obtained then the determination of water saturation can be calculated by the formula method Archie, Indonesia, and Simandoux. Then obtained the average result of the water saturation with an Archie method of layer A of 80.57% and layer B of 55.03%. Average water saturation calculation using Indonesian method obtained by the result of layer A 34.3627% and layer B of 28,236%. Average water saturation calculation using Simandoux method obtained the result of layer A of 22.0805% and layer B of 8,255% and determined which method is selected for reservoir A and Reservoir B. Reservoir A and B reserves are calculated Based on volumetric method with A volume of bulk reservoirs of 23333.69 Acre ft and A volume of bulk reservoir B of 37854.49 Acre ft, the reservoir water saturation using Indonesian method on reservoir A of 34.3627% and saturation of reservoir water of B 28,236%, the initial oil formation volume factor (Boi) of 1.0531 BBL/STB is 13.1211 MMSTB on the A and 40.2064 MMSTB Reservoir on the B Reservoir.