Historical development of the gravity method in exploration

Geophysics ◽  
2005 ◽  
Vol 70 (6) ◽  
pp. 63ND-89ND ◽  
Author(s):  
M. N. Nabighian ◽  
M. E. Ander ◽  
V. J. S. Grauch ◽  
R. O. Hansen ◽  
T. R. LaFehr ◽  
...  
Keyword(s):  
Oil And Gas ◽  
Gravity Data ◽  
Low Cost ◽  
Dynamic Environment ◽  
Massive Sulfide ◽  
Airborne Gravity ◽  
Gravity Gradiometry ◽  
Positioning Systems ◽  
Gravity Method ◽  
Marine Gravity

The gravity method was the first geophysical technique to be used in oil and gas exploration. Despite being eclipsed by seismology, it has continued to be an important and sometimes crucial constraint in a number of exploration areas. In oil exploration the gravity method is particularly applicable in salt provinces, overthrust and foothills belts, underexplored basins, and targets of interest that underlie high-velocity zones. The gravity method is used frequently in mining applications to map subsurface geology and to directly calculate ore reserves for some massive sulfide orebodies. There is also a modest increase in the use of gravity techniques in specialized investigations for shallow targets. Gravimeters have undergone continuous improvement during the past 25 years, particularly in their ability to function in a dynamic environment. This and the advent of global positioning systems (GPS) have led to a marked improvement in the quality of marine gravity and have transformed airborne gravity from a regional technique to a prospect-level exploration tool that is particularly applicable in remote areas or transition zones that are otherwise inaccessible. Recently, moving-platform gravity gradiometers have become available and promise to play an important role in future exploration. Data reduction, filtering, and visualization, together with low-cost, powerful personal computers and color graphics, have transformed the interpretation of gravity data. The state of the art is illustrated with three case histories: 3D modeling of gravity data to map aquifers in the Albuquerque Basin, the use of marine gravity gradiometry combined with 3D seismic data to map salt keels in the Gulf of Mexico, and the use of airborne gravity gradiometry in exploration for kimberlites in Canada.

Is there any room for gravity in petroleum exploration? Let's open the door again!

2020 ◽  
Vol 60 (2) ◽  
pp. 761
Author(s):  
Sergey Shevchenko
Keyword(s):  
Oil And Gas ◽  
Gravity Data ◽  
Low Cost ◽  
Petroleum Industry ◽  
Oil And Gas Industry ◽  
Petroleum Exploration ◽  
Geophysical Method ◽  
Gas Industry ◽  
Gravity Method ◽  
1960S And 1970S

The seismic method has been thriving in the oil and gas industry for decades. Technological progress in acquisition, processing and interpretation have made it practically the only geophysical method used for petroleum exploration. Unfortunately, gravity, as a pioneering geophysical method appears to have been completely forgotten in Australia’s oil and gas industry. Most of the gravity data in Australia were collected in the 1960s and 1970s. Only government agencies and a few exploration companies have conducted gravity surveys in petroleum basins since that time. Australia’s mostly flat terrain, economical aspects of the gravity method such as low cost and the ability to cover vast underexplored onshore basins in the country, all seem to be positive factors indicating that this method should be commonly used as a part of petroleum exploration. Given the petroleum industry is currently trying hard to make exploration more economically effective, this may be an opportunity to revive the gravity method in petroleum exploration.

A new method for underwater dynamic gravimetry based on multisensor integrated navigation

Geophysics ◽  
2020 ◽  
Vol 85 (3) ◽  
pp. G69-G80
Author(s):  
Zhiming Xiong ◽  
Juliang Cao ◽  
Kaixun Liao ◽  
Meiping Wu ◽  
Shaokun Cai ◽  
...  
Keyword(s):  
Oil And Gas ◽  
Finite Impulse Response ◽  
Gravity Data ◽  
Satellite System ◽  
New Method ◽  
Integrated Navigation ◽  
Oil And Gas Exploration ◽  
Half Wavelength ◽  
Marine Gravity ◽  
Global Navigation Satellite

Underwater gravity information plays a major role in deepwater oil and gas exploration. To realize underwater dynamic gravimetry, we have developed a strapdown gravimeter mounted in a pressure capsule for adaption to the underwater environment and we adopted a two-stage towed underwater gravimetry scheme. An improved strapdown gravimeter and other underwater sensors were installed in a towed vessel to form an underwater dynamic gravimetry system. Because the global navigation satellite system cannot be used for underwater dynamic gravimetry, we developed a new method based on underwater multisensor integrated navigation, in which a federal Kalman filter was applied for error estimation. This new method allowed us to obtain the accurate attitude, velocity, and position necessary for gravity estimation. In addition, the gravity data can then be extracted from the noisy data through finite impulse response low-pass filtering. We acquired the underwater gravity data at a depth of 300 m to test the validity of the new method and evaluate the accuracy of the underwater gravity system. The results indicated a repeatability from 0.85 to 0.96 mGal at a half wavelength of approximately 0.2 km and also indicated good consistency with the marine gravity data.

Airborne gravity is here!

Geophysics ◽  
1983 ◽  
Vol 48 (2) ◽  
pp. 213-223 ◽  
Author(s):  
Sigmund Hammer
Keyword(s):  
Research And Development ◽  
Oil And Gas ◽  
Gravity Data ◽  
Airborne Gravity ◽  
New Era ◽  
Geophysical Exploration

The achievement of practical and useful airborne gravity exploration for petroleum is a major culmination of more than twenty years of research and development. Commercial surveys have now been conducted for three years. The precision and anomaly resolution attainable are twice as good as that of current shipborne gravity data. This paper presents data to demonstrate the precision of airborne gravity and discusses its usefulness (with simultaneous magnetics and topography). Industrial acceptance of the method portends a new era in geophysical exploration for oil and gas which gives promise to double the effectiveness of explorations on land in both time and cost.

Three‐dimensional regularized focusing inversion of gravity gradient tensor component data

Geophysics ◽  
2004 ◽  
Vol 69 (4) ◽  
pp. 925-937 ◽  
Author(s):  
Michael S. Zhdanov ◽  
Robert Ellis ◽  
Souvik Mukherjee
Keyword(s):  
Local Density ◽  
Mineral Exploration ◽  
Gravity Data ◽  
Three Dimensional ◽  
Tensor Component ◽  
Airborne Gravity ◽  
Gravity Gradient ◽  
Gravity Method ◽  
Density Anomaly ◽  
And Inversion

We develop a new method for interpretation of tensor gravity field component data, based on regularized focusing inversion. The focusing inversion makes its possible to reconstruct a sharper image of the geological target than conventional maximum smoothness inversion. This new technique can be efficiently applied for the interpretation of gravity gradiometer data, which are sensitive to local density anomalies. The numerical modeling and inversion results show that the resolution of the gravity method can be improved significantly if we use tensor gravity data for interpretation. We also apply our method for inversion of the gradient gravity data collected by BHP Billiton over the Cannington Ag‐Pb‐Zn orebody in Queensland, Australia. The comparison with the drilling results demonstrates a remarkable correlation between the density anomaly reconstructed by the gravity gradient data and the true structure of the orebody. This result indicates that the emerging new geophysical technology of the airborne gravity gradient observations can improve significantly the practical effectiveness of the gravity method in mineral exploration.

Study on Elliptic Filters in Airborne Gravity Data Processing

2013 ◽  
Vol 341-342 ◽  
pp. 999-1004
Author(s):  
Wei Zhou ◽  
Ti Jing Cai
Keyword(s):  
Data Processing ◽  
Gravity Data ◽  
Airborne Gravity ◽  
Optimal Parameters ◽  
Evaluation Indicator ◽  
Filter Order ◽  
Upper Limit ◽  
Optimal Value ◽  
Low Pass ◽  
Stopband Attenuation

For low-pass filtering of airborne gravity data processing, elliptic low-pass digital filters were designed and filtering influences of the elliptic filter order, upper limit passband frequency, maximal passband attenuation and minimal stopband attenuation were studied. The results show that the upper limit passband frequency has the greatest effect on filtering among four parameters; the filter order and the maximal passband attenuation have some influence, but instability will increase with larger order; the effect of the minimal stopband attenuation is not obvious when reaching a certain value, which requires a combination of evaluation indicator accuracy to determine the optimal value. The standard deviations of discrepancies between the elliptic filtered gravity anomaly with optimal parameters and the commercial software result are within 1mGal, and the internal accord accuracy along four survey lines after level adjusting is about 0.620mGal.

Sediment Stripping Correction to Marine Gravity Data

2014 ◽  
Vol 37 (4) ◽  
pp. 419-439 ◽  
Author(s):  
Wenjin Chen ◽  
Robert Tenzer ◽  
Xiang Gu
Keyword(s):  
Gravity Data ◽  
Marine Gravity

scholarly journals Fast, Robust, and Low-Cost Microwave Imaging of Multiple Non-Metallic Pipes

Electronics ◽  
2021 ◽  
Vol 10 (15) ◽  
pp. 1762
Author(s):  
Yuki Gao ◽  
Maryam Ravan ◽  
Reza K. Amineh
Keyword(s):  
Antenna Arrays ◽  
Oil And Gas ◽  
Imaging System ◽  
Imaging Techniques ◽  
Low Cost ◽  
Microwave Imaging ◽  
Airport Security ◽  
Destructive Testing ◽  
Security Screening ◽  
Industrial Sectors

The use of non-metallic pipes and composite components that are low-cost, durable, light-weight, and resilient to corrosion is growing rapidly in various industrial sectors such as oil and gas industries in the form of non-metallic composite pipes. While these components are still prone to damages, traditional non-destructive testing (NDT) techniques such as eddy current technique and magnetic flux leakage technique cannot be utilized for inspection of these components. Microwave imaging can fill this gap as a favorable technique to perform inspection of non-metallic pipes. Holographic microwave imaging techniques are fast and robust and have been successfully employed in applications such as airport security screening and underground imaging. Here, we extend the use of holographic microwave imaging to inspection of multiple concentric pipes. To increase the speed of data acquisition, we utilize antenna arrays along the azimuthal direction in a cylindrical setup. A parametric study and demonstration of the performance of the proposed imaging system will be provided.

ANALISIS MODEL 3D DATA GAYA BERAT DALAM KEGAGALAN PEMBORAN SUMUR RESERVOAR MINYAK DI AREA X

2020 ◽  
Vol 2 (2) ◽  
pp. 62-68
Author(s):  
Ahmad Jahrudin ◽  
Pradityo Riyadi
Keyword(s):  
3D Modeling ◽  
3D Model ◽  
Oil And Gas ◽  
Gravity Data ◽  
Production Well ◽  
Log Data ◽  
3D Data ◽  
Area X

The exploration of oil and gas, especially in Indonesia is experiencing various challenges and varying degrees of difficulty. In this research, the researcher tries to make a 3D modeling from gravity data, where the model will show a structure to determine the central coordinates for drilling. Pertamina has carried out drilling at a location in NTT and it turns out that the well does not produce oil and gas, even though the log data reads an oil showing that the area should have the prospect of producing oil, but the wells that have been drilled do not show any oil or gas, therefore the researchers tried to make a 3D model determine the structure around the production well. In this research, it was seen that the area of the previous drilling point had deviated from the top of the up dome and it was also seen in this structure that the area was deviated by about 3 kilometers and depth must exceed 526 m, the researcher concluded that the drilling point must be at X, Y coordinates.

Deepwater Steel Catenary Riser System Design for Lingshui 17-2 Project

2021 ◽  
Author(s):  
Ning He ◽  
Hu Yang ◽  
Fanli Xu ◽  
Yongming Cheng
Keyword(s):  
South China Sea ◽  
System Design ◽  
South China ◽  
Oil And Gas ◽  
Low Cost ◽  
Northern South China Sea ◽  
Steel Catenary Riser ◽  
China Sea ◽  
Scr System ◽  
The Impact

Abstract A riser is a key component for transporting produced oil and gas from the subsea wells to the surface production vessel. Through nearly 30 years of design and implementation, Steel Catenary Risers (SCRs) have been found to have the advantages of relatively low cost and good adaptability to floating platform’s motion. This paper investigates deepwater SCR system design for the Lingshui 17-2 (termed LS17-2) project. This paper first introduces a SCR system for the LS17-2 project. The field for this project is located in the northern South China Sea, with water depth of 1220m to 1560m. LS17-2 consists of a subsea production system, a deep-draft semi-submersible (SEMI), and an export riser/pipeline. The platform was designed to have a large storage capacity with a variable draft during its operation. Based on deepwater SCR engineering experience, the key SCR design challenges are summarized from the engineering executive perspective. The challenges to the SCR system design for the LS17-2 project include harsh environment condition in South China Sea and the impact on fatigue design for the requirement of 30-years’ service life. They call for design optimization and innovative ideas. The engineering design and analysis are discussed together solutions. To demonstrate the deepwater SCR system design for LS17-2 project, examples are provided to illustrate the challenges and solutions. The experience learned from this paper should have significant relevance to future SCR design.

Sign in / Sign up

Export Citation Format

Share Document