Posts Tagged Seismic

Seismic Exploration for Minerals

Posted by on Thursday, 20 February, 2014


Seismic and airborne geophysics for copper project in southeast Arizona

Posted by on Saturday, 14 December, 2013

Millrock Resources Inc. recently completed a seismic geophysical survey and drilling of a single reverse circulation borehole at its Monsoon copper project in southeast Arizona. The survey results and the drill hole indicate that it is unlikely that a large porphyry copper deposit exists within 500 m of surface. The project was the subject of an option agreement with FQM (Akubra) Inc, formerly Inmet Mining Corporation, a wholly owned subsidiary of First Quantum Minerals Ltd. (“FQML”) whereby FQML may have earned a 70% joint venture interest. FQML has advised Millrock that it will withdraw from the option agreement. Millrock believes there is potential for discovery of a porphyry copper deposit at greater depth and intends to seek a new funding partner to further test the targets developed.

Prior to the recent exploration phase Millrock had carried out property-wide biogeochemical sampling, soil sampling, water well sampling, and airborne ZTEM and magnetic surveys. The work was designed to search for buried porphyry copper deposits along the projected trend of the Safford copper deposits in Laramide-aged rocks that host copper mineralization in the district.

Reprocessing and interpretation of historic seismic data had led Millrock to believe that an upthrown structural block of Laramide-aged rock may be present, and that copper mineralization may exist in the shallow subsurface. A modern 2D seismic reflection survey was carried out to confirm the historic survey in an area where Millrock had discovered polymetallic anomalies in various geochemical surveys. Two lines totaling approximately 17 km were surveyed. Two possible interpretations could be made from the seismic data. One interpretation indicated the favourable Laramide contact was at an approximate depth of 500 m below surface. Another interpretation indicated a depth of approximately 1,000 m.

A vertically-oriented 500 m reverse circulation hole was drilled as a stratigraphic test and to determine the source of the geochemical anomaly. Results of the drilling suggest that an upthrown structural block does exist in the area tested. Tertiary volcanic rock was intersected at only 100 m below surface; a much shallower level than in holes drilled by prior explorers elsewhere on the property. However, the contact with the Laramide aged rocks must lie deeper than 500 m; most likely at an approximate depth of 1,000 m.

The technical information within this document has been reviewed and approved by Gregory A. Beischer, President & CEO of Millrock. Mr. Beischer is a Qualified Person as defined in NI 43-101.

Target: The target at the Monson property is a giant high-grade porphyry copper deposit (± gold and molybdenum). The project is located approximately 50 km (31 mi) south of the Morenci Mine and 50 km (31 mi) southeast of the Safford Mine, both giant porphyry copper deposits actively being mined by Freeport McMoran.

The property is covered by post-mineral Tertiary volcanic rocks or alluvium and remains largely untested for porphyry copper mineralization. Geochemical, geophysical and geologic data, however, suggests potential for the discovery of a buried porphyry copper deposit at Monsoon.

Location and Setting: The Monsoon property is located near Duncan in southeastern Arizona approximately 50 km (31 mi) southeast of Safford, Arizona. Topography varies from moderate to flat. Paved highway 70 passes just east of the property with good access to the property provided by dirt roads.

Geology and Mineralization: The Monsoon property is located southeast of the Safford Mine along the Safford porphyry copper trend as defined by known mineralization at the Safford (Dos Pobres, Lone Star, San Juan and Sanchez), Sol and San Jose porphyry copper properties. Geochemical and geophysical data further defines the Safford trend through the Monsoon property

The project area is covered by post-mineral Tertiary volcanic rocks and alluvium, however geochemical, geophysical and geologic data suggests potential for the presence of a buried porphyry copper deposit. Past drilling is limited to two shallow holes drilled in the 1990′s by Noranda. Neither hole penetrated Laramide-aged basement, drilling only post mineral alluvium. Zones containing anomalous copper and molybdenum values were intersected in both holes. The Laramide-aged geology of the property remains largely unknown and the porphyry copper potential unexplored.


3-D seismic survey to define shape and size of unprecedented PGE mineralization

Posted by on Thursday, 17 October, 2013
Ivanhoe Mines reports unprecedented 90-metre intersection of 4.51 grams of platinum, palladium, rhodium and gold per tonne, plus 0.37% nickel and 0.20% copper, at its Flatreef exploration and development project on South Africa’s Bushveld Complex
Intercept includes a 40-metre section grading 6.88 grams of platinum, palladium, rhodium and gold per tonne, plus 0.51% nickel and 0.21% copper.

Chief Executive Officer, has announced that the company has intersected mineralization containing 4.51 grams per tonne of platinum, palladium, rhodium and gold (4PGE) over 90.64 metres (297 feet) at a 1 g/t 3PE cut-off in a recently drilled hole at the underground Flatreef platinum, palladium, nickel, copper, gold and rhodium discovery, which is part of the company’s Platreef Project in South Africa’s Bushveld Complex.

The 90.64-metre intersection in Hole TMT006 also includes:

  • a 40.79-metre (134-foot) section grading 6.88 grams per tonne 4PGE at a 3g/t 3PE cut-off;
  • additional nickel and copper mineralization grading 0.37% nickel and 0.20% copper, plus a platinum-to-palladium ratio of approximately 1 to 1, over the entire 90-metre intersection.

“This is an extraordinary drill hole,” said Mr. Friedland. “The 90-metre thickness of the intercept, which roughly is the same height as a 30-storey building, is unprecedented at Flatreef and I believe it also is without precedent in an underground platinum discovery in South Africa.

“The scale of the mineralized intercept has obvious implications for the contained PGMs and base metals in the open-ended Flatreef poly-metallic discovery. The combined grade and thickness of the PGMs and base metals mineralization seen in this hole far exceeds anything we’ve previously encountered in all of our years of delineating resources on our Platreef Project.”

The gentle dips in the Flatreef Discovery area mean that the drilled thickness approximates true thickness.
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3-D seismic survey to better define shape and size of Flatreef Discovery

Ivanhoe Mines will undertake a 3-D geophysical seismic survey over the Flatreef Discovery before beginning site preparation work for the bulk-sample shaft. The seismic survey is expected to begin later this week and be completed in early November 2013.

Mr. Johansson said that it has become standard practice at many South African mines to conduct 3-D seismic surveys prior to sinking new shafts or beginning major underground developments. The seismic survey will provide Ivanhoe’s engineers with high-resolution imaging of the Flatreef mineralized zones ahead of the planned mining development.

About the Platreef Project

The Platreef Project is a Tier One discovery of platinum-group elements, nickel, copper and gold that contains the Flatreef underground deposit, on the Bushveld’s Northern Limb, north of the town of Mokopane and approximately 280 kilometres northeast of Johannesburg. The project is located on two contiguous rights, Turfspruit and Macalacaskop, which adjoin Anglo Platinum’s Mogalakwena mining operations.

In June 2013, Ivanhoe Mines filed a Mining Right Application (MRA) for the Platreef Project with the Department of Mineral Resources. A Mining Right allows a company to mine and process minerals optimally from the mining area for a period of 30 years, which may be extended upon application.

The Flatreef Mineral Resource, with a strike length of six kilometres, predominantly lies within a flat to gently dipping portion of the Platreef mineralized belt at relatively shallow depths of approximately 700 to 1,100 metres below surface.

The Flatreef Deposit is characterized by its very large vertical thicknesses of high-grade mineralization and the platinum-to-palladium ratio of approximately 1:1, which is significantly higher than other PGM discoveries on the Bushveld’s Northern Limb. The grade shells used to constrain mineralization in the Flatreef Indicated Resource area have average true thicknesses of approximately 24 metres at a 2.0 grams per tonne (g/t) 3PE (platinum-palladium-gold) cut-off grade, with an equivalent average resource grade of 4.1 g/t 4PE (platinum-palladium-gold-rhodium), 0.34% nickel and 0.17% copper. Flatreef’s Indicated Mineral Resources of 214 million tonnes contain an estimated 28.5 million ounces of platinum, palladium, gold and rhodium, 1.6 billion pounds of nickel and 800 million pounds of copper.

At the same cut-off of 2.0 g/t 4PE, the latest Flatreef estimate includes Inferred Mineral Resources of 415 million tonnes grading 3.5 g/t 4PE, 0.33% nickel and 0.16% copper, containing an estimated additional 47.2 million ounces of platinum, palladium, gold and rhodium, 3.0 billion pounds of nickel and 1.5 billion pounds of copper. Inferred mineral resource estimates, under the CIM guidelines, do not have demonstrated economic viability and may never achieve the confidence to be mineral reserve estimates or to be mined.


Deep Crustal Seismic Reflection Profiling in Australia

Posted by on Wednesday, 11 September, 2013

Deep Crustal Seismic Reflection Profiling Australia 1978–2011 (B.L.N. Kennett, E. Saygin, T. Fomin and R. Blewett) presents the full suite of reflection profiles penetrating the whole crust carried out in Australia from 1978-2011 by Geoscience Australia and various partners. The set of reflection data comprises over 12,000 km of coverage across the whole continent, and provides an insight into the variations in crustal architecture in the varied geological domains. Each reflection profile is presented at approximately true scale with up to 220 km of profile per page and overlap between pages. Each reflection section is accompanied by a geological strip map showing the configuration of the line superimposed on 1:1M geology. The compilation includes a number of large scale reflection transects groups of 1,000 km or more that link across major geological provinces, and an extensive bibliography of reports and relevant publications.

Details and downloading..


Seminar to honour Professor Emeritus Tadeusz Ulrych

Posted by on Thursday, 1 August, 2013

A seminar to honour Professor Emeritus Tadeusz Ulrych will be held in Vancouver, B.C. on Thursday September 5, 2013. It will be a day of invited talks on a range of topics related to signal processing and geophysics in honour of our friend and teacher, Tad.

Date: Thursday September 5, 2013
Venue: University Golf Club Vancouver, BC
Presentations and lunch: 9:00 a.m. – 5:00 p.m.
Reception: 5:00-7:00 p.m.

Speakers from international academia and industry include:

  • Evgeny Landa, “Beyond conventional …”
  • Scott Leaney, “From scale space to anisotropic moment tensors, punctuated with portraits”
  • Toshifumi Matsuoka, “TBA” =
  • Jaymie Matthews, “Asteroseismology: Stealing the geoseismologists’ guide book and launching it into space “
  • Brian Russell, “Instantaneous anything“
  • Mauricio Sacchi, “Sparsity and Nuclear Norm Regularization for Multidimensional (5D) Seismic Data Processing “
  • Michael Slawinski, “Monte-Carlo analysis of Frobenius-norm effective elasticity tensors”
  • Stewart Trickett, “Robust rank-reduction filtering for erratic noise”
  • Danilo Velis, “Very fast simulated annealing for the automatic detection of microseisms”
  • Arthur Weiglein, “Tad Ulrych: the inspiration behind inverse scattering group therapy and seismic psychoanalysis”
  • Iain Weir-Jones, “TBA”

Details


The technology for fracture estimation

Posted by on Wednesday, 5 June, 2013

MicroSeismic, Inc. (MicroSeismic) has announced that is has introduced the Productive-SRV™ (Productive-Stimulated Reservoir Volume). The multiple patents pending technology introduces a novel method to estimate how much of the stimulated fracture remains open through proppant placement. Productive-SRV incorporates three microseismically derived calculations to estimate target zone productivity; a magnitude calibrated Discrete Fracture Network (DFN), the Propped Fracture Estimation and the Fat Fracture™ Drainage Estimation. The combination of these techniques can be used to estimate 90-day cumulative production.

“Hydraulic fracturing has been effective at stimulating fractures in the subsurface for more than 60 years,” said Michael Thornton, Ph.D., Chief Technology Officer, MicroSeismic. “However, increasing hydrocarbon recovery requires those fractures to stay open. The overburden pressure of 10,000 feet of rock will quickly close a fracture if it is not wedged open with proppant. Productive-SRV helps our clients quickly determine which completion techniques are most effective by estimating the effects of proppant placement at optimum well spacing.”

Productive-SRV is determined from integrating microseismic data with known treatment parameters and near wellbore geology and geomechanics. By estimating the volume of fractures that are likely proppant filled, on a per stage basis, a more constrained area of stimulation is determined, providing a more accurate correlation to early production.

Productive-SRV is to be included as part of the standard surface, near surface and downhole microseismic services provided by MicroSeismic.


Airborne Gravity and Magnetic Data Acquisition in Kenya

Posted by on Friday, 26 April, 2013

CAMAC Energy Inc.  has announced that Sander Geophysics Limited (“SGL”) has completed shooting  airborne gravity and magnetic geophysical surveys on the Company’s Kenya onshore Lamu Basin Blocks L1B and L16 (“Blocks”). The data acquisition covers essentially the entire 12,129 square kilometers in Block L1B and the entire 3,613 square kilometers in Block L16 and satisfies the gravity and magnetic survey requirements for each Block under the relevant Production Sharing Agreements.

The Company expects to receive initial results of the shoot in the third quarter of 2013. Results will be used to optimize the placement of 2-D seismic lines by identifying faults, basement structures and intra-sedimentary volcanic layers and/or intrusions.

“I am pleased that we completed the acquisition of the airborne gravity and magnetic geophysical surveys in Kenya safely, on time, and under budget,” said Senior Vice President of Exploration and Production Segun Omidele. “Our geophysical team will now work with SGL to interpret the data and delineate optimal areas for 2-D seismic acquisition.”


Practical Inversion for Geoscientists

Posted by on Wednesday, 10 April, 2013

A short course on the why, how, and what of geophysical inversion

Presented by the B.C. Geophysical Society

This is a 2-day workshop consisting of 1 day of lectures (April 24th) followed by a 1 day hands-on workshop (either April 25th or 26th). Delegates can register for just the lectures or both the lectures and workshop.

Registration available until April 15th at: www.bcgsonline.org

Date: April 24th – 26th 2013

Address: SFU Downtown Campus; Vancouver BC

Registration: Registration is now open!  Please fill out attached pdf form (link below) and click submit.  Registration will be complete once payment is made via Paypal link.  Delegates are asked to choose one workshop day among April 25th or 26th.

Day 1 – Introduction to inversion
– Introduction to inversion in exploration

Reasons for doing inversion
Range of inversion options: magnetics, gravity, EM, IP-resistivity, seismic
Fitting geology and data

– Background on inversion

Unconstrained/constrained
Joint and collaborative
The future of inversion

– Before inversion – forward modeling

forward modeling
petrophysics drives the story
complexity vs. adequacy

– Case studies

Potential fields
EM
IP-resistivity

Day 2 – Workshop with Case studies
Multi-disciplinary teams will use geological, geophysical and geochemical data from two deposits (Babine Lake porphyry Cu-Mo, BC and Minto Cu, YK) to develop exploration targets. Teams will present their evaluations of the data to stimulate group discussion.

Inversion results for the available geophysical surveys will be presented to demonstrate state-of-the-art technology and best practices.
Sponsors for the short course are currently being solicited. Please contact Victoria Sterritt at Victoria.Sterritt@teck.com for details. Proceeds go to the KEGS Foundation.
For those interested in more information about the short course, please email info@bcgsonline.org


“Peter Duncan to Be Honored at Geophysical Society Spring Symposium”

Posted by on Sunday, 10 February, 2013

MicroSeismic, Inc. announced that Peter Duncan, Ph.D. will be honored for a lifetime achievement in geophysics at the Geophysical Society of Houston (GSH) and Society of Exploration Geophysicists (SEG) 2013 Spring Symposium on March 5 and 6. As part of the symposium, Peter will host a Challenge Bowl on March 5 and will be the guest of honor at the March 6 banquet toasting and roasting him.

“I am extremely surprised and grateful to receive this prestigious honor and join a group of honorees for whom I have deep admiration,” stated Peter Duncan, Ph.D., Founder and CEO of MicroSeismic. “I have dedicated my life to the study of geophysics and the advancement of that field of work; to be honored by these two organizations means the world to me.”

Peter is an active volunteer with many organizations including GSH and SEG. He chaired GSH’s Continuing Education Committee for two years and SEG’s Continuing Education Committee for three years. In the late 1990′s, he was responsible for creating the SEG Distinguished Instructor Short Course format. Peter served as the SEG President in 2003 and in the fall of 2008, he was the SEG/AAPG Distinguished Lecturer and spoke on the subject of passive seismic at 45 venues around the world. His most treasured accomplishment with SEG is the development of the successful Challenge Bowl where he continues to be its biggest promoter and host. Challenge Bowl events are held annually around the world, with local and regional eliminations leading to a world championship at the SEG Annual Meeting.

For registration and details of event visit http://www.gshtx.org/en/cev/932.


Seismic, gravity and magnetotelluric dataset from Geoscience Australia

Posted by on Thursday, 31 January, 2013

The final seismic, gravity and magnetotelluric dataset from Geoscience Australia’s Onshore Energy Security Program has been processed and released.

The data were acquired in 2011 by Geoscience Australia in conjunction with the Geological Survey of Western Australia (GSWA) as part of the Western Australian Government’sRoyalties for Regions Exploration Incentive Scheme. The 484 kilometres of data were obtained over the Yilgarn Craton, Officer Basin and Musgrave Province of Western Australia. This survey will provide precompetitive data for energy and mineral exploration, and for potential water resources. These data, combined with the 2001 Northern Yilgarn Survey, and the 2010 Capricorn and Youanmi Surveys result in a complete cross section of central Western Australia.

Overall, more than 6500 kilometres of deep crustal seismic data were acquired during the Onshore Energy Security Program, providing valuable structural information for the Australian crust from the near surface to the Moho, boundary between the Earth’s crust and the mantle. As well as providing precompetitive data, the surveys have helped to expand understanding of the complex structures and geology of the Australia continent.

The processed SEGY data, images and ancillary information are now available for free download.

Interpretation of the seismic and magnetotelluric models undertaken by GSWA and Geoscience Australia geoscientists will be presented at a public workshop in Perth in June 2013.


About Seismic Interpretation

Posted by on Sunday, 9 December, 2012

Robin Westerman : “Absolute BME: Quantitative Seismic Interpretation”

Roxar Software: “RMS 2012 – Seismic Inversion and Attributes”



2D High Resolution Seismic on Norfolk Prospect

Posted by on Wednesday, 21 November, 2012

North Sea Energy Inc. announces that a 2D hi-resolution seismic program on the Norfolk Prospect (block 12/16b) (20% NSE interest) has been completed after receiving approval from DECC (UK Department of Energy and Climate Change).

The weather during November has been favourable and allowed us to acquire more data than the base plan. This will allow us to test 3D migrating the data and/or creating a Geocube product.

The processing of the additional seismic will enhance our understanding of the prospect in terms of the ‘up dip’ extent of the Norfolk prospect and assist in the determination of the drilling target. The acquiring of the seismic data this year allows us to progress our evaluation of the prospect and to make a drilling decision sooner and without delay to the project.

About Norfolk Prospect and Norfolk East Prospect – 12/16b and 12/17b

The blocks are located in the Inner Moray Firth, a short distance from the Sutherland coast. The Norfolk prospect is a large stratigraphic pinchout and dip closure of the lower cretaceous Coracle sands with additional leads in the Punt and Beatrice sands. The best estimate undiscovered oil initially-in-place of 209.0 MMstb at Norfolk and 55.5 MMstb at Norfolk East as estimated for NSE in Sproule’s Report dated July 31, 2011.


3D seismic program in Saskatchewan

Posted by on Tuesday, 16 October, 2012

Edge Resources Inc.  recently drilled two oil wells in Primate, Saskatchewan (see announcement August 13, 2012).

Based on the early successful production results in Primate, Edge has undertaken a 3D seismic program in order to fine-tune the multitude of additional drilling locations in the newly discovered Primate oil pool. The Company expects to shoot and evaluate approximately 10 square kilometers (3.7 square miles) of 3D seismic, which will add to the Company’s impressive 65 square kilometers (25 square miles) of existing, proprietary 3D seismic assets in Saskatchewan. The focus of this program is to further characterize the drilling locations in the recently discovered oil pool known as Asset East. However, the seismic extends beyond the new pool onto Edge’s neighboring 100% owned, contiguous lands, where it may reveal additional drilling opportunities.

Brad Nichol, President and CEO of Edge commented, “We were sufficiently pleased with the initial results from the two wells in Primate to shoot 3D seismic and hone the additional locations on our existing lands. The results in Primate have exceeded our expectations on many levels and production rates are getting closer to stabilizing and are continually increasing.” Nichol added, “We’re also very keen on the Grand Forks locations, which are being drilled into a well-understood, seismically-defined reservoir. We expect production to be on-stream within a few days after these wells are completed.”


3D seismic survey in Australia

Posted by on Friday, 12 October, 2012

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Holloman Energy Corporation announces that acquisition of 127 square kilometres of a 3-D seismic data on Petroleum Exploration License (“PEL”) 112 has been successfully completed. The 3-D seismic program was executed by the Australian operations group of Geokinetics Inc. Holloman understands that the data obtained by its farm-in partner, Terra Nova Energy Inc., is of excellent quality and represents a vast improvement (in subsurface imaging) over the seismic data previously available on PEL 112.

Terra Nova has commenced seismic data processing. Once complete, the geophysical program will be interpreted with potential drill locations expected in mid-December 2012. Terra Nova is also in the process of securing a drilling rig to drill up to six wells in 2013. It is anticipated that the first well will be drilled on PEL 112, subject to rig availability, late in the first calendar quarter of 2013. Under the terms of its farm-in agreement on PEL 112 and PEL 444, Terra Nova is required to place AUD$4,500,000 in escrow on November 1, 2012 to support the upcoming drill plan.

News released by Cooper Energy earlier this month confirms the continued success of their drilling efforts on the Cooper Basin’s western flank. Cooper Energy reported that the success of it Butlers-5 oil well in PEL 92 has been followed by similar results from its Butlers-6 well. Each well penetrated gross oil columns ranging from 5 to 8 metre in the Namur Sandstone and have been suspended for completion as oil producers. The oil finds on PEL 92 are situated 25 kilometres north/northwest of PEL 112 on lands believed to be of a similar geological model.

On PEL 444, Terra Nova is in the process of designing a 150 km2 3D seismic program for completion in 2013.

The Cooper Basin’s most productive sediments for petrochemicals were formed during the Permian period, which ended about 250 million years ago.  Since the end of this era, the Permian’s rich organic sediments have been increasingly buried under additional layers of rock, thus forming deposits of coal, oil, natural gas, and other petrochemicals.Because of the geological history of the Australian continent, the Permian sediments in Central Australia primarily occurred in one distinct region – the Cooper Basin.  This basin is surrounded by and underlies a portion of the much larger Eromanga Basin, which is mostly comprised of younger sandstones and sediments from the more recent Jurassic and Cretaceous periods.  It is these younger formations that overlie the Cooper Basin’s Permian sediments, thus trapping (or “capping”) the petrochemicals underground and creating Australia’s richest oil and gas producing region. There has been a recent surge in drilling activity for oil in the last five years with many new Jurassic Eromanga discoveries being made along the southwestern flank of the Cooper Basin


Seismoelectric & Microgravity in the last FastTIMES issue

Posted by on Tuesday, 9 October, 2012

The EEGS has published the latest issue of FastTIMES, news for the near-surface geophysical sciences. It is available as a pdf document optimized for screen viewing or printing.

Seismoelectric & Microgravity

Volume 17, Number 2, June 2012


Wireless Seismic Technology in Alaska’s Cook Inlet

Posted by on Thursday, 4 October, 2012

Houston-based Apache Corp. has become the first producer to use true-cable free wireless seismic technology offshore Alaska to limit the impact of seismic activity on Cook Inlet’s wildlife, communities and environment – including Cook Inlet beluga whales.

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The use of wireless 3-D seismic is part of Apache’s commitment to conducting 3-D seismic operations in Alaska’s Cook Inlet “in ways that limit the impact on communities and the environment,” the company said in a July 24 article on its website, addressing criticisms of its seismic program.

Apache is using true cable-free nodal recording systems, designed and manufactured by Sugar Land, Texas-based FairfieldNodal, in order to minimize the impact of its seismic survey on Cook Inlet’s wildlife population and environment.

“Because we’re shooting onshore and offshore, we have to go back and meld and blend the data for the different sections together,” said Lisa Parker.

The company is using the technology for its ongoing 3D seismic survey of Cook Inlet, which will encompass onshore, offshore and the transition zone of Apache’s acreage. The seismic survey will continue for the next two and a half years.

After acquiring leases on 850,000 acres in Cook Inlet in August 2010, Apache began the permitting process for its seismic and exploration programs. In an effort to address concerns over the impact of seismic activity on local wildlife and the environment, Apache conducted a technology test to compare how traditional cable seismic would perform versus a wireless system.

Impressed with what it saw, the company initiated the permitting process to utilize wireless seismic and received approval to use this technology in the spring of 2011.
Apache began its Cook Inlet seismic program in November 2011, and has been working continuously since then, save for a six-week break from Christmas through the first part of February.

Approximately 1.4 billion barrels of oil was discovered in Cook Inlet in its early development in the 1950s and 1960s. Exploration and production in Cook Inlet declined after the discovery of Prudhoe Bay. Only a handful of fields have been discovered in Cook Inlet, but the field size distribution strongly suggests another 1.3 to 1.4 billion barrels of oil remain to be discovered in the Cook Inlet basin, Apache said.

Apache will begin drilling in Cook Inlet in October.

Fairfield’s product is truly cable free, unlike nodes from manufacturers who have elected to keep the power supply, electronics and sensor connected with short cables and connectors, said Roger Keyte head of marketing and business development at FairfieldNodal.

The nodes are placed on the ocean floor or buried onshore. Except for a rope tied to nodes placed offshore to retrieve them – the rope is not involved in the spacing of the node – the nodes have no cables, said Keyte.

Marine nodes weigh 65 pounds and look like a 50-pound free weight, but are a bit thicker, said Lisa Parker, head of government relations for Apache in Alaska. Land nodes weigh 4.8 pounds and look like a two-pound coffee can with a spike on the bottom. Both types of nodes are made of plastic and stainless steel.

The nodes are retrieved after a period time and taken back to the office, where the data is downloaded and the nodes are recharged. The data is then forwarded to Apache’s geoscientists for interpretation.

“Because we’re shooting onshore and offshore, we have to go back and meld and blend the data for the different sections together,” said Lisa Parker, head of government relations for Apache in Alaska. “It’s like putting the pieces of a puzzle back together.”

Since 1924, traditional seismic systems have involved sensors connected to cables. These sensors transmitted signals back to a localized recording system to be converted into digits, said Keyte.

Using a system with heavy, cumbersome cables presents difficulties onshore and offshore, Keyte noted. Offshore, the cables mean seismic vessels can’t get close to structures in the water such as rigs and platforms. Traditional systems also tend to be noisier.

Using cabled system onshore was especially problematic, with electrical leakages occurring due to animals biting or chewing the cables or sweat from the hands of workers, said Keyte.

Utilizing a true cable-free system cuts down on the amount of time crews spend troubleshooting to fix leakages. The cable free system increases the reliability of data and allows the recording time to be controlled.

More details


The ‘Low-down’ on Land Seismic Acquisition

Posted by on Tuesday, 11 September, 2012

The Australian Society of Exploration Geophysicists (WA Branch) invites you to attend the upcoming ASEG WA Tech Night presented by Tim Dean of WesternGeco Geosolutions.

Land seismic is currently undergoing what, in a generally slowly evolving field, amounts to a revolution. This revolution involves the use of a variety of new technologies but is principally concerned with reduction. The introduction of high channel-count recording systems has enabled reliable point-receiver acquisition. Coupled with advanced data processing techniques this enables a reduction in the number of sensors required on the crew. This in turn results in reduction in the number of crew members and thus survey cost, including the environmental cost. Acquisition cost can also be reduced through the use of advanced source acquisition methodologies that reduce the source cycle time (the time taken between the acquisition of records). An increase in the size of vibrators has also allowed a reduction in the number of vibrators on the crew and their related logistic burden.

An area of particular interest currently is the recording of data with enhanced the low-frequency content of the data. Increased low-frequency content has a variety of benefits, it helps overcome the high-frequency attenuating effects of the earth, improves vertical resolution, enhances inversion results, and improves: velocity analysis, minimum phase deconvolution and wavelet estimation. Acquiring such data involves lowering both the minimum frequency transmitted by the source as well as the ability of the sensors to record such frequencies.

Read more..