Integrated Pore Pressure Prediction Using Seismic Velocity and Appraisal Well Data for a Virgin Reservoir Undergoing Depletion From Nearby Fields

2014 ◽  
Author(s):  
Kelvin Okpako ◽  
Prahlad Basak ◽  
Godwin Abia ◽  
Seyi Odegbesan ◽  
Simon Roya
Keyword(s):  
Pore Pressure ◽  
Seismic Velocity ◽  
Pore Pressure Prediction ◽  
Well Data

Seismic pore pressure prediction without well data and poorly defined normal compaction trend lines: a case study from the Río Bravo Delta, Northern Mexico

2005 ◽  
Author(s):  
Juan C. Clarembaux ◽  
Marcelo Giusso ◽  
Roberto Gullco ◽  
Daniel Mujica ◽  
Carlos Carabeo Miranda ◽  
...  
Keyword(s):  
Pore Pressure ◽  
Northern Mexico ◽  
Pore Pressure Prediction ◽  
Rio Bravo ◽  
Well Data

scholarly journals Pore pressure prediction in Niger Delta high pressure, high temperature (HP/HT) domains using well logs and 3D seismic data: a case study of X-field, onshore Niger Delta

2021 ◽  
Vol 11 (10) ◽  
pp. 3747-3758
Author(s):  
Abdulquadri O. Alabere ◽  
Olayemi K. Akangbe
Keyword(s):  
High Pressure ◽  
High Temperature ◽  
Pore Pressure ◽  
Niger Delta ◽  
Seismic Velocity ◽  
Sedimentary Basins ◽  
Geothermal Gradient ◽  
Pore Pressure Prediction ◽  
Fracture Gradient ◽  
High Temperature High Pressure

AbstractFew wells targeting high temperature, high pressure intervals in most tertiary sedimentary basins have achieved their objective in terms of technicalities and cost. Since most shallow targets have been drilled, exploration focus is drifting into deeper plays both onshore and in deep offshore areas. To ensure safe and economic drilling campaigns, pore pressure prediction methodologies used in the region needs to be improved. The research aims at generating and testing a modification of Eaton’s equation fit for high temperature, high pressure intervals on a field. The evolution of pore pressure in the field was established from offset well data by making several crossplots, and fracture gradient was computed using Mathew and Kelly’s equation. Eaton’s equation parameters were then calibrated using several wells until a desired field scale result was achieved when compared with information from already drilled intervals i.e., kicks and RFT data. Seismic velocity data resulting from high density, high resolution velocity analysis done to target deep overpressured intervals were then used to predict 1D pore pressure models at six selected prospect locations. Analyses reveal depths shallower than 3800 m TVD/MSL with geothermal gradient 3.0 °C/100 m and pressure gradient less than 1.50sg EMW are affected mainly by undercompaction; depths greater than 3800 m TVD/MSL with geothermal gradient of 4.1 °C/10 m and pressure gradients reaching 1.82–2.12sg EMW are affected by unloading with a narrow drilling margin for the deep highly pressured prospect intervals. Eaton’s n-exponent was modified to 6, and it proved accurate in predicting high overpressure in the first prospect wells drilled.

Predrill pore‐pressure prediction using seismic data

Geophysics ◽  
2002 ◽  
Vol 67 (4) ◽  
pp. 1286-1292 ◽  
Author(s):  
C. M. Sayers ◽  
G. M. Johnson ◽  
G. Denyer
Keyword(s):  
Velocity Field ◽  
Gulf Of Mexico ◽  
Pore Pressure ◽  
Seismic Data ◽  
Seismic Velocities ◽  
Pressure Data ◽  
Pore Pressure Prediction ◽  
Well Data ◽  
Interval Velocities ◽  
Reflection Tomography

1A predrill estimate of pore pressure can be obtained from seismic velocities using a velocity‐to–pore‐pressure transform, but the seismic velocities need to be derived using methods having sufficient resolution for well planning purposes. For a deepwater Gulf of Mexico example, significant differences are found between the velocity field obtained using reflection tomography and that obtained using a conventional method based on the Dix equation. These lead to significant differences in the predicted pore pressure. Parameters in the velocity‐to–pore‐pressure transform are estimated using seismic interval velocities and pressure data from nearby calibration wells. The uncertainty in the pore pressure prediction is analyzed by examining the spread in the predicted pore pressure obtained using parameter combinations which sample the region of parameter space consistent with the available well data. If calibration wells are not available, the ideas proposed in this paper can be used with measurements made while drilling to predict pore pressure ahead of the bit based on seismic velocities.

scholarly journals Initial pore pressures under the Lusi mud volcano, Indonesia

2015 ◽  
Vol 3 (1) ◽  
pp. SE33-SE49 ◽  
Author(s):  
Mark Tingay
Keyword(s):  
Pore Pressure ◽  
Mud Volcano ◽  
Prediction Methods ◽  
Pressure Gradients ◽  
Modern Times ◽  
Fine Grained ◽  
High Magnitude ◽  
Pore Pressures ◽  
Pore Pressure Prediction ◽  
Well Data

The Lusi mud volcano of East Java, Indonesia, remains one of the most unusual geologic disasters of modern times. Since its sudden birth in 2006, Lusi has erupted continuously, expelling more than 90 million cubic meters of mud that has displaced approximately 40,000 people. This study undertakes the first detailed analysis of the pore pressures immediately prior to the Lusi mud volcano eruption by compiling data from the adjacent (150 m away) Banjar Panji-1 wellbore and undertaking pore pressure prediction from carefully compiled petrophysical data. Wellbore fluid influxes indicate that sequences under Lusi are overpressured from only 350 m depth and follow an approximately lithostat-parallel pore pressure increase through Pleistocene clastic sequences (to 1870 m depth) with pore pressure gradients up to [Formula: see text]. Most unusually, fluid influxes, a major kick, connection gases, elevated background gases, and offset well data confirm that high-magnitude overpressures also exist in the Plio-Pleistocene volcanic sequences (1870 to approximately 2833 m depth) and Miocene (Tuban Formation) carbonates, with pore pressure gradients of [Formula: see text]. The varying geology under the Lusi mud volcano poses a number of challenges for determining overpressure origin and undertaking pore pressure prediction. Overpressures in the fine-grained and rapidly deposited Pleistocene clastics have a petrophysical signature typical of disequilibrium compaction and can be reliably predicted from sonic, resistivity, and drilling exponent data. However, it is difficult to establish the overpressure origin in the low-porosity volcanic sequences and Miocene carbonates. Similarly, the volcanics do not have any clear porosity anomaly, and thus pore pressures in these sequences are greatly underestimated by standard prediction methods. The analysis of preeruption pore pressures underneath the Lusi mud volcano is important for understanding the mechanics, triggering, and longevity of the eruption, as well as providing a valuable example of the unknowns and challenges associated with overpressures in nonclastic rocks.

scholarly journals WELL-SEISMIC INTEGRATION TO PORE PRESSURE PREDICTION USING MULTIVARIATE GEOSTATISTICS: A CASE STUDY IN A BRAZILIAN EQUATORIAL MARGIN BASIN

2020 ◽  
Vol 38 (1) ◽  
pp. 32
Author(s):  
Flávia Braz Ponte ◽  
Francisco Fábio de Araújo Ponte ◽  
Adalberto Silva ◽  
Alberto Garcia Figueiredo
Keyword(s):  
Pressure Gradient ◽  
Pore Pressure ◽  
Seismic Velocity ◽  
Multivariate Geostatistics ◽  
Geostatistical Approach ◽  
Pore Pressure Prediction ◽  
Pore Pressure Gradient ◽  
Gradient Models ◽  
Pressure Analysis

ABSTRACT. Pore pressure modeling has been fundamental on several applications and stages of hydrocarbon exploration, evaluation, development and production. Pore pressure estimation is generally obtained from seismic velocity data and pore pressure analysis on wells. There are many methods available for pore pressure analysis, although more recently the application of the geostatistical approach is increasing in popularity and proving to be an important method for pore pressure gradient prediction in challenging areas where pore pressure prediction is difficult using deterministic methods. In this case study on a new frontier area in the Brazilian Equatorial Margin, multivariate geostatistics allowed integration of data at different scales and spatial variations of seismic and well variables produce pore pressure gradient models. The final result is a geopressure model where one can easily extract well-conditioned pore pressure information at any location.Keywords: geostatistical approach, different scales, pore pressure gradient models. INTEGRAÇÃO POÇO-SÍSMICA PARA PREDIÇÃO DE PRESSÃO DE POROS USANDO A GEOSTATÍSTICA MULTIVARIADA: UM ESTUDO DE CASO EM UMA BACIA DA MARGEM EQUATORIAL BRASILEIRARESUMO. A modelagem de pressão de poros tem sido fundamental em diversas aplicações e etapas da exploração, avaliação, desenvolvimento e produção de hidrocarbonetos. Em geral, a estimativa de pressão de poros é obtida a partir da integração de dados de velocidade sísmica e análise de pressão em poços. Existem diversos métodos para análise de pressão de poros, entretanto, atualmente, a aplicação da abordagem geoestatística está crescendo em popularidade e provando ser um importante método para predição de gradiente de pressão de poros em áreas de fronteiras onde a previsão de pressão de poros usando métodos determinísticos não é bem sucedida. Neste estudo de caso, localizado em uma área de nova fronteira na Margem Equatorial Brasileira, a geoestatística multivariada permitiu a integração das variáveis sísmicas e de poço em diferentes escalas e variações espaciais e a obtenção de modelos de gradiente de pressão de poros. Os resultados geraram um modelo de geopressão no qual a extração de valores de pressão de poros bem condicionados é simples em qualquer parte da área.Palavras-chave: abordagem geostatistica, diferentes escalas, modelos de gradiente depressão de poros.

Sign in / Sign up

Export Citation Format

Share Document