“Improved methods for interpreting magnetic gradient tensor data” David Clark, CSIRO Materials Science and Engineering (Australia).

17-Mar-2010  from 16:00 to 17:00 , Department of Physics of U of T.

Recent technological advances suggest that we are on the threshold of a new era in applied magnetic surverys, where acquisition of magnetic gradient tensor data will become routine. In the meantime, modern ultrahigh resolution conventional magnetic data can be use to calculate gradient tenor elements from TMI or TMI gradient surveys. Until the present, not a great deal of attention has been paid to processing and interpretation of gradient tensor data. New methods for inverting gradient tensor surveys to obtain source parameters have been developed for a number of elementary, but useful, models. these include point pole, line of poles, point dipole (sphere), line of dipoles ( horizontal cylinder), thin and think dipping sheets and sloping step models. A key simplification is the use of eigenvalues and associated eigenvectors of the tensor.

Source: http://www.physics.utoronto.ca/

Ivan Hrvoic, President of GEM, explains REQUIREMENTS FOR OBTAINING HIGH ACCURACY WIТН PROTON MAGNEТOMERS.

“Demystifying Gravity and Magnetic Geophysical Exploration Methods” – the training course which is going to be on May 4, 2010 in Calgary, Alberta.

This basic one-day course reviews the fundamental geological and physical concepts that lie behind oil and mineral exploration using gravity and magnetic geophysical methods. This course is presented in plain English with minimal math or technical jargon. This course is designed for professional and technical personnel who encounter gravity and magnetic surveys, and need to understand the basics of these geophysical methods in order to assess their suitability and effectiveness under various exploration circumstances.

Course Outline

• Geological Meaning of Geophysical Anomalies: Anomaly-Lithology
• Relationships and Relevant Rock Properties
• Forms of Rock Bodies Encountered in Oil and Mineral Exploration
• Gravity Exploration Methods
• Magnetic Exploration Methods
• Design of Gravity and Magnetic Surveys for Geologic Targets
• Processing Methods for Gravity and Magnetic Data to Separate and
• Enhance Desirable Anomalies
• Data Display and Anomaly Enhancement
• Exploration Example: Gravity and Magnetic Studies of Alberta Basement Structure
• Exploration Example: Gravity and Magnetic Studies in a Frontier Basin Offshore British Columbia

Registration: http://www.progress-seminars.com/

The RN-10-05 hole, targeting an airborne geophysical survey (VTEM) anomaly, has been started, with an anticipated hole length of 500 m. These holes are testing targets in the Magoo Lake area, located approximately 1.5 km northwest of the Discovery Zone. Five additional holes ranging in depth between 325 m and 700 m are planned and will target VTEM, DeepEM surface survey and Borehole Pulse EM geophysical survey anomalies. Total drilling anticipated in this program is estimated to be 3,000 m.

Hole RN-10-10 will target a large conductive modeled plate near the recently completed drilling on the Tower Zone, and is planned to be 700 m in length. Company geologists have recognized the potential extension of the Discovery Zone rhyolite in this area. This target will be drilled later in the program, as it can be drilled from ground that is accessible all year round.

Deep penetrating ground geophysical surveys have identified new conductive targets northeast and along strike of the Tower Zone over a strike length of approximately 1 km. These are untested anomalies and deeper than any previously drilled in the northeast Tower area. Three holes, each testing a new anomaly, will be drilled. Anomalies have been modeled below 300 m from surface. Hole RN-10-09 will test the deepest target in the area and has a planned length of 700 m.

drill holes RN-10-07 and RN-10-08 will test geophysical conductors located in the vicinity of an historical drill hole which reported multiple intervals of disseminated, stringer and near solid to solid sulphide, with anomalous copper, zinc and silver values in altered volcanic rock. Reprocessed historical geophysical survey data, including bore hole survey data, has been merged with VMS VTEM airborne survey data and more recent ground deep EM survey results.

These three drill targets, located on mining claim P6805E, are spatially associated with the Company’s recent surface pulse electromagnetic survey that outlined several highly conductive plates directly associated with, or flanking, a magnetic response.

A VTEM anomaly with a coincident magnetic high defined on mining claim P5643E will also be drilled. It is located approximately 2 km east-northeast of the Phase 1 Tower Zone drilling area.  This target has a lateral extent of over 700 m and based on modeling of electromagnetic data is suggestive of stacked conductive zones. Historical drilling results in the area have reported strongly altered volcanic rock and sulphide mineralization with anomalous copper and zinc. The geological setting of these conductors is interpreted to be very favorable for hosting base metal massive sulphide-type deposits of the Flin Flon-Snow Lake belt.

Drilling on mining claim P1019F will target two separate VTEM anomalies near Magoo Lake.  Historical work completed by Noranda Exploration in this region outlined highly anomalous copper and zinc values in a highly chlorite-altered volcanic host rock. This geological setting is also favorable for the formation of base metal massive sulphide mineralization and two holes are planned to test the targets.

Legendary Richard Smith – high level practical and theoretical EM specialist is going to give the lecture on the 25, March, 2010 – 11:30am in Calgary.

http://www.publish.csiro.au/?act=view_file&file_id=EGv41n1toc.pdf

SEG eBooks beta launched in early February 2010 with approximately 35 books, and SEG plans to add 15 more titles within two months. SEG will add new books online as they are published in print and plans to add legacy titles in the years ahead.

SEG eBooks content is searchable via its own search engine or with those covering the SEG Digital Library and Scitation. Browsing is available by title, year, series, and topic. Introductory material and back matter (mostly indexes and references) are free.

The Controlled-Source Audio-Frequency Magnetotellurics (CSAMT) survey was conducted by Zonge Geosciences Inc. for Otis Gold Corp., between October 19th and October 27th 2009 and consisted of data acquisition from six N45E-oriented survey lines for a total of 8.5 line-kilometers of coverage. Detailed geophysical interpretation of the CSAMT survey data was conducted by James L. Wright of J. L. Wright Geophysics, Spring Creek, Nevada, during the latter half of December 2009.

Otis Gold Corp. announces the results of a recent CSAMT geophysical survey that indicates the presence of numerous sizeable and geologically significant resistivity anomalies underlying the Dog Bone Ridge gold target area located at the Kilgore Gold Project, Clark County, Idaho. The target area, which has only been minimally tested by historic drilling, is located approximately 1,200 meters southwest of the known Kilgore gold deposit and comprises most of the core of the larger epithermal system containing the deposit (see http://www.otisgold.com/news/06-10-2008/ and http://www.otisgold.com/blog/gold-intercepts-at-kilgore/). Of the five CSAMT anomalies detected by the survey, only three have been initially tested by historic drilling, with all drill holes in these three anomalies containing significant intercepts of gold mineralization.

Based on the lack of drilling and the fact that the anomalies are sizeable (upwards of 1,200 meters in length), a 2,000-meter, 6-hole drill program is planned to test the highest priority anomalies and offset some of the known historic drill-hole intercepts during the 2010 field season. This drilling is part of a larger 8,000-meter drill program planned for the Kilgore Gold Project in 2010.

The Dog Bone Ridge gold target comprises an extensive area of 242 hectares mostly overlain by an apron of Pliocene-age hot-spring sinter and explosion breccia that caps lithic tuff, the same rock unit that hosts the Company’s nearby Kilgore gold deposit. Of the three CSAMT anomalies associated with historic and significant drill-hole intercepts, the most northerly (Target C1) coincides with Kilgore Gold Company drill holes KG04-02 containing 51.8 m @ 1.25 grams/tonne (“g/t”) gold (“Au”) and KG06-01 with 12.6 m @ 1.57 g/t Au. Within the hole KG04-02 intercept a higher-grade intercept of 3.1 m @ 15.9 g/t Au was reported that coincides directly with the slightly higher resistive core of the anomaly, possibly reflecting a silicified structure. The second, or central, CSAMT anomaly (Target D3) associated with historic drill-hole intercepts coincides with Echo Bay core hole 96EKC-178 that contains 99.4 m @ 0.428 g/t Au and further contains within this intercept higher grade intercepts of 4.6 m @ 2.57 g/t Au, 10.7 m @ 1.51 g/t Au, and 3.1 m @ 2.57 g/t Au. Gold mineralization in these holes is hosted within silicified lithic tuff.

A detailed location map of the CSAMT survey grid lines and resultant anomalies, along with the historic drill-hole intercepts associated with these targets, can be found on the Otis website at http://www.otisgold.com/projects/kilgore . Although a few additional and widely scattered historic holes were drilled in the Dog Bone Ridge target area, they either were not drilled deep enough to reach the newly discovered CSAMT anomalies or they were angled away from and/or off the flanks of them, missing them completely.

Terra Energy & Resource Technologies, Inc., a natural resource exploration technology company, has completed an exploration services project for oil and gas in Nevada under a contract with Golden Eagle Alliance, LLC, a Colorado limited liability company.

The contract entailed the application of STeP®, Terra’s proprietary remote sensing exploration technology, with the objective being to assess the hydrocarbon potential of a certain area in Nevada.

STeP®, Sub Terrain Prospecting, is a satellite-based proprietary technology which interprets and quantifies electro-magnetic radiation of the Earth to assess and determine presence of geological structures with oil and gas, diamonds, gold and, other subsurface mineral deposits on or off shore.

The basis of STeP is in the use of thematic processing of recent Remote Earth Sensing (RES) data combined with sophisticated mathematical techniques and processing of geological/geophysical data.  Proprietary algorithms and specialized software quantify related information to locate and identify subsurface minerals and geology.

“We welcomed this project because we had an opportunity to showcase the STeP® technology in one of the most challenging frontier areas,” said Dmitry Vilbaum, Chief Executive Officer of Terra Energy & Resource Technologies. “Nevada is known for risky exploration and lack of success of traditional geological and geophysical science application. Our technology was used to reduce the risk and exploratory guess work. As Terra’s technology suite continues to demonstrate success, exploration companies in the United States are recognizing its robust capabilities as an exploration tool,” Dmitry added.

In opining that the oil and gas potential for the area is fairly good, Mr. Vilbaum also stated: “The territory is within the regional ‘fairway’ of mature Mississippian source rocks capable of generating oil. Wells drilled to the west and east of the area of interest have reported numerous, encouraging oil shows. In this project, we were asked to focus on an area with known oil and gas source rocks and the potential for commercial accumulations of hydrocarbons, although the nearest oil production is located approximately 50 miles away.”

“Given our recent announcement of plans to engage in exploration for our own account, this Nevada project has been a good exercise for Terra,” said Dr. Alexandre Agaian, Terra Energy & Resource Technologies’ President. “We expect to utilize the STeP® analysis in our plans to develop a portfolio of interests in explorations in more established oil and gas states such as Texas and Oklahoma.”

Joint SEG/SPE/AAPG Workshop

Submit your abstract by 5 March to participate in the upcoming “Joint SEG/SPE/AAPG Workshop on Shales: Seal, Reservoir, Source,” 6-9 June in Austin, Texas. The 5 March deadline is fast approaching, apply now.

Now accepting applications for the 2010 D&P Forum
Submit your application before 31 March for the 2010 D&P Forum: CO₂ EOR & Sequestration, taking place 18-22 August in Boston, USA.

2010 Summer Research Workshop
Submit an abstract for the upcoming workshop “Subsalt Exploration and Development: Four years later, what’s new in acquisition, imaging, and interpretation?” scheduled 26-29 July at the Squaw Valley Resort in Lake Tahoe, California, USA. The deadline to submit is 20 April.

Denver 2010 Annual Meeting call for papers
The Technical Program Committee invites you to submit your papers for consideration beginning in March. Start preparing your papers for submission by reading the 2010 Abstract Kit.