Difference between revisions of "Magnetotellurics case history: frontier basin analysis (Amazon Basin, Colombia)"
Jump to navigation
Jump to search
Cwhitehurst (talk | contribs) |
Cwhitehurst (talk | contribs) m (added Category:Treatise Handbook 3 using HotCat) |
||
| (9 intermediate revisions by 2 users not shown) | |||
| Line 6: | Line 6: | ||
| part = Predicting the occurrence of oil and gas traps | | part = Predicting the occurrence of oil and gas traps | ||
| chapter = Applying magnetotellurics | | chapter = Applying magnetotellurics | ||
| − | | frompg = 16- | + | | frompg = 16-8 |
| − | | topg = 16- | + | | topg = 16-8 |
| author = Arnie Ostrander | | author = Arnie Ostrander | ||
| link = http://archives.datapages.com/data/specpubs/beaumont/ch16/ch16.htm | | link = http://archives.datapages.com/data/specpubs/beaumont/ch16/ch16.htm | ||
| Line 14: | Line 14: | ||
| isbn = 0-89181-602-X | | isbn = 0-89181-602-X | ||
}} | }} | ||
| − | A regional exploration program to study a large unexplored area in the Colombian Amazon basin was conducted by Amoco Production Company in 1987 and 1988.<ref name=ch16r2>Burgett, W. | + | A regional exploration program to study a large unexplored area in the Colombian [http://http://www.greatestplaces.org/notes/amazon.htm Amazon basin] was conducted by [http://http://www.britannica.com/EBchecked/topic/21168/Amoco-Corporation Amoco Production Company] in 1987 and 1988.<ref name=ch16r2>Burgett, W. A., A. Orange, and R. F. Sigal, 1992, Integration of MT, seismic, gravity, and magnetic data for reconnaissance of the Colombian Amazon: 54th meeting, European Association of Exploration Geophysicists, Expanded Abstracts, p. 428–499.</ref> This study area was very large approximately 300,000 km<sup>2</sup> (115,000 mi<sup>2</sup>) and remote with dense jungle cover, rugged terrain, and limited road access. |
| − | The first phase of the program consisted of 31,700 km (19,700 mi) of airborne gravity and [[magnetics]]. The large-scale structures delineated in these surveys were then further investigated by MT The MT survey was feasible with a light helicopter because the crew was small and equipment was light and compact. Data were collected from 43 sites, with a typical spacing of 10–20 km (6–12 mi). | + | The first phase of the program consisted of 31,700 km (19,700 mi) of [[Gravity basics|airborne gravity]] and [[magnetics]]. The large-scale structures delineated in these surveys were then further investigated by [[magnetotellurics]] (MT). The MT survey was feasible with a light helicopter because the crew was small and equipment was light and compact. Data were collected from 43 sites, with a typical spacing of 10–20 km (6–12 mi). |
==Survey results== | ==Survey results== | ||
| Line 24: | Line 24: | ||
The MT data clearly delineated a thick sedimentary section with internal units that could be correlated from site to site. Three resistivity “packages” were observed: | The MT data clearly delineated a thick sedimentary section with internal units that could be correlated from site to site. Three resistivity “packages” were observed: | ||
| − | * 40–100 | + | * 40–100 ohmm (sedimentary) |
| − | * 150–250 | + | * 150–250 ohmm (sedimentary) |
| − | * >1000 | + | * >1000 ohmm (crystalline [[basement]]) |
| − | [[:file:applying-magnetotellurics_fig16-5.png|Figure 1]] shows a simulated cross section in the Amazon basin based on MT data. | + | [[:file:applying-magnetotellurics_fig16-5.png|Figure 1]] shows a simulated [[cross section]] in the Amazon basin based on MT data. |
==Post-MT program== | ==Post-MT program== | ||
Encouraged by the evidence from the MT survey, Amoco decided to shoot a small seismic program and drill a shallow stratigraphic test. This program was positioned on the edge of a subbasin defined in the MT data. There generally was good agreement between the MT data, the seismic data, and the borehole geology. | Encouraged by the evidence from the MT survey, Amoco decided to shoot a small seismic program and drill a shallow stratigraphic test. This program was positioned on the edge of a subbasin defined in the MT data. There generally was good agreement between the MT data, the seismic data, and the borehole geology. | ||
| − | The airborne gravity and magnetic data, followed by the surface MT survey, provided a very cost-effective means of regional basin definition and led directly to a well-positioned seismic survey and well site. | + | The airborne [[gravity]] and magnetic data, followed by the surface MT survey, provided a very cost-effective means of regional basin definition and led directly to a well-positioned seismic survey and well site. |
==See also== | ==See also== | ||
| Line 53: | Line 53: | ||
[[Category:Predicting the occurrence of oil and gas traps]] | [[Category:Predicting the occurrence of oil and gas traps]] | ||
[[Category:Applying magnetotellurics]] | [[Category:Applying magnetotellurics]] | ||
| + | [[Category:Treatise Handbook 3]] | ||
Latest revision as of 15:12, 31 January 2022
| Exploring for Oil and Gas Traps | |
| |
| Series | Treatise in Petroleum Geology |
|---|---|
| Part | Predicting the occurrence of oil and gas traps |
| Chapter | Applying magnetotellurics |
| Author | Arnie Ostrander |
| Link | Web page |
| Store | AAPG Store |
A regional exploration program to study a large unexplored area in the Colombian Amazon basin was conducted by Amoco Production Company in 1987 and 1988.[1] This study area was very large approximately 300,000 km2 (115,000 mi2) and remote with dense jungle cover, rugged terrain, and limited road access.
The first phase of the program consisted of 31,700 km (19,700 mi) of airborne gravity and magnetics. The large-scale structures delineated in these surveys were then further investigated by magnetotellurics (MT). The MT survey was feasible with a light helicopter because the crew was small and equipment was light and compact. Data were collected from 43 sites, with a typical spacing of 10–20 km (6–12 mi).
Survey results[edit]
Figure 1 Simulated cross section in the Amazon basin based on MT data. Drafted from data in Burgett et al.[1]
The MT data clearly delineated a thick sedimentary section with internal units that could be correlated from site to site. Three resistivity “packages” were observed:
- 40–100 ohmm (sedimentary)
- 150–250 ohmm (sedimentary)
- >1000 ohmm (crystalline basement)
Figure 1 shows a simulated cross section in the Amazon basin based on MT data.
Post-MT program[edit]
Encouraged by the evidence from the MT survey, Amoco decided to shoot a small seismic program and drill a shallow stratigraphic test. This program was positioned on the edge of a subbasin defined in the MT data. There generally was good agreement between the MT data, the seismic data, and the borehole geology.
The airborne gravity and magnetic data, followed by the surface MT survey, provided a very cost-effective means of regional basin definition and led directly to a well-positioned seismic survey and well site.
See also[edit]
- Magnetotellurics
- Magnetotellurics survey measurements
- Magnetotelluric data acquisition
- Magnetotellurics case history: rugged carbonate terrain (Highlands of Papua New Guinea)
- Magnetotellurics case history: Precambrian overthrust (Northwestern Colorado)
- Magnetotellurics case history: volcanic terrain (Columbia River Plateau)
References[edit]
External links[edit]
| find literature about Magnetotellurics case history: frontier basin analysis (Amazon Basin, Colombia) |
|
|
|
|