Tech Division Events
Structural Geology Division
For more information concerning this Division, please contact the Division Chair, William (Jamie) Jamison, Hef Petrophysical Consultants, jamie@hef.com, (403) 269-3158.
Division Profile
The Structural Division's mandate is to provide a forum for CSPG members who are interested in structural geology and tectonic processes, and to showcase what is new and current in structural geology. Topics are wide-ranging and include both compressional and extensional tectonics.
The division aims to provide informal brownbag talks every month from September to May. Talks typically average about 45 minutes followed by a short question/discussion period, and are currently located on the 17th floor of the Petro-Canada West Tower, 150 6th Ave. S.W. Speakers for the luncheons are sought from industry and academia, and new volunteers are always welcome.
The division also hosts at least one field trip per year. These trips are informal and are lead by volunteers within the structural community. They are designed to be low cost, and involve no more than one evening away from home.
If you are interested in joining the Structural Division e-mail listing which
currently provides luncheon reminders and a few other notices of
interest to the structural community, if you care to suggest a technical
topic or present a talk to the division, or if you have a field trip
idea, please contact William (Jamie) Jamison at (403) 269-3158 or jamie@hef.com.
Division Talks
Integrating Discrete Fracture Network Models and Pressure Transient Data for Fractured Reservoir Characterization
Speaker
Steve Rogers,
Golder Associates Ltd.
12:00 noon
Thursday, May 8, 2008
Petro-Canada
West Tower, room 17B/C (17th floor)
150 6 Ave SW
Calgary, Alberta
Abstract
The difficulties in characterizing fractured reservoirs are numerous. The conversion of structural data into meaningful reservoir properties has been particularly troublesome. The main source of fracture geometric data for static models is image log data, which address mainly fracture intensity and orientation. The emphasis of these parameters in the static model helps perpetuate the belief that "all fractures are equal". However, we know that fracture conductivity tends to follow highly skewed statistical distributions where most of the fracture population is weighted to smaller values.
Thus flow in fractures tends to concentrate in a relatively small number of fractures in the high-end tail of the of the conductance (or aperture) distribution. This explains why flow in the wellbore in fractured formations is often controlled by a relatively few features. In order to adequately capture the scale of these important features within fracture network models we require direct flow indicators, such as production logs, mud-loss records and well tests as well, as other geometric data.
Of these hydraulic measures, only well testing provides information about how the natural fracture network extends away from the well bore. The well test pressure derivative is a valuable source of information on the conducting network geometry, but it requires insights from fracture network models that go well beyond standard well-response models. Discrete Fracture Network tools provide the link between the wellbore static and dynamic data to produce simulations that honor both.
Examples will be presented from both fractured and faulted reservoir studies to illustrate how static fracture information and pressure transients can be integrated together to help identify the features that control production, reduce uncertainty in scenario modeling and derive accurate reservoir model input parameters for fractured reservoir models.
Biography
Steve Rogers is a Senior Geoscientist with Golder Associates Ltd based in Vancouver, BC. He holds a Geology & Management Science degree from Keele University, UK (1987) and a Ph.D. from Nottingham University in rock mass characterization and rock mechanics (1991).
Rogers initially worked for the British Geological Survey and was heavily involved with a wide variety of fracture characterization efforts of the UK and European Radioactive Waste Disposal investigations. Between 1996 and 1998 he was seconded to the Government of the Republic of Vanuatu to help manage their national Geology Department.
In 2000 he joined Golder Associates (UK) Ltd to help develop their fractured reservoir services business and in 2005 moved to Western Canada with Golder Associates Ltd. During his time with Golder Associates he has worked on a variety of fractured reservoir projects around the world, specializing in the conceptualization and modeling of fractured reservoirs.
The Application of LiDAR to the Mapping of Mountains
Speaker
Willem Langenberg,
Alberta Geological Survey / ERCB
Edmonton, Alberta
12:00 Noon
Thursday, June 5, 2008
Petro-Canada
West Tower, room 17B/C (17th floor)
150 6th Ave SW
Calgary, Alberta
Abstract
Canadians, such as George M. Dawson and John A. Allan, were great at mapping mountains. Nowadays, the use of airborne LiDAR (an acronym for Light Detection and Ranging) is becoming increasingly common in mapping mountains.
LiDAR systems employ intense pulses of light, typically generated by lasers, and sensitive optical detectors to receive the reflected pulses. Airborne LiDAR systems consist of a laser machine mounted beneath an airplane or helicopter that follows a predefined path. The ground is then scanned by means of tens of thousands of pulses per second emitted from the laser. In order to obtain measurements for the horizontal coordinates (x, y) and elevation (z) of the objects scanned, the position of the aircraft is determined using accurate differential GPS measurements and the distance from the aircraft to the ground calculated. These measurements generate a 3-dimensional cloud of points with irregular spacing. Left unfiltered, the model includes treetops, buildings and vehicles and the image looks like a picture. Many of these non-ground features can be removed to produce a bare-earth digital Elevation Model (DEM), which is especially useful for geologists.
The Alberta Geological Survey purchased LiDAR data for a 33 km2 area covering Turtle Mountain. Trees and buildings were removed by filtering and the resulting bare earth DEM shows details of rock structures, which are concealed in regular aerial photos mainly due to vegetation cover. Draping existing geological map over this DEM allows refinement of these maps. The trace of the Turtle Mountain Thrust as displayed on a GSC geological map from 1993 and a 2007 AGS map can be more accurately placed. In addition, the trace of the axial plane and stratigraphic contacts on the Turtle Mountain Anticline can be accurately placed on the DEM. Contacts needed adjustments of up to 150 m on the existing maps. The trace of the steeply dipping main coal seam, which was mined in the Frank Coal mine from 1901 to 1918, can also be accurately mapped from well defined mine subsidence pits.
The University of Lausanne (and the Canton de Vaud) obtained LiDAR images of the Morcles Nappe from Swisstopo, the Swiss Geo-information Centre. The geology of the 'Diablerets' map-sheet (from swisstopo) was draped over the DEM and GIS technology allowed the area to be viewed down-plunge. These views can be compared with down-plunge cross sections of cylindrical domains. In the Haute Pointe area, the precise location of the lower contact of the Urgonian (Barremian) lithostratigraphic unit could be shown to be 100 m southeast from the location mapped in the 1980s. In other areas, contacts were mapped more than 100 m away from their true location. Faults could also be located more precisely.
The remarkable feature about LiDAR is its capability to remove non-ground objects. LiDAR presents a valuable tool to recognize features that would otherwise remain obscured by vegetation. It is anticipated that this technique combined with improved cross sectioning methods will revolutionize the mapping of mountains.
Biography
Willem Langenberg is a senior geologist with the Alberta Geological Survey (ERCB) in Edmonton, Alberta. He obtained a Ph.D. in structural geology from the University of Amsterdam in the Netherlands in 1973. He has been employed by the University of Amsterdam, the University of Alberta, Alberta Research Council, Alberta Department of Energy and the Alberta Resources Conservation Board.
Langenberg has had a longstanding career in structural geology, with emphasis during the last twenty-five years on economic geology (including energy and mineral resources). He performed the function of Project Control Officer on the inter-governmental Turtle Mountain Monitoring Project from 2003-2005. He is presently conducting investigations on the structure of the Alberta Foothills and Mountains and has a weak spot for the geology of Turtle Mountain (Crowsnest Pass). Recently, he has also worked on coals of the Coalspur, Scollard and Horseshoe Canyon formations. He authored or co-authored 35 refereed articles in scientific journals, four AGS Bulletins and many AGS reports and abstracts of oral and poster presentations.
He is a member of APEGGA, the Geological Association of Canada, the Canadian Society of Petroleum Geology and the Geological Society of America. He was Publication Manager of the Edmonton Geological Society from 1993-2003 and Associate Editor of the Bulletin of the Geological Society of America from 1991-95.
CSPG Structural Division – 2006 Workshop / Fieldtrip: postscript
The Structural Division of the CSPG hosted a two-day workshop/field trip on September 26 and 27, 2006 in Kananaskis Country. The central topic was "lateral structural changes in thrust belts." The first day of this event was devoted to presentations (in the comfort of a conference room in Kananaskis village) and the second to road stops and hikes to various features between Porcupine Creek and Highwood Pass. A total of 38 geoscientists attended, representing both federal and provincial geological surveys, the two main Alberta universities and many companies of the Calgary oil patch.
Both conference room and outcrop presentations were made by a large number of the attendees, and the associated discussions (arguments) were abundant and productive. The format and venue worked very well, and the weather cleared for a spectacular hike to Desolation Pass (see photo). Thanks, in particular, to Anadarko Canada for providing a bus, to Petro-Canada for providing the projector and roadside safety equipment, and to Elizabeth Atkinson for handling the bulk of the logistics.
Photo caption: View along strike to the north from Desolation Pass. Devonian and Mississippian carbonates within the Misty and Rundle thrust sheets have been offset across several major tear/transverse faults. Photo by Don Buscarello.
Information
Talks are free; please bring your lunch. Goodies
and drinks are provided by HEF Petrophysical Consulting, and the
room is provided by Petro-Canada. If you would like to be
on the Structural Division e-mail list, or if you'd like to give
a talk, please contact William (Jamie) Jamison, Hef Petrophysical
Consultants, jamie@hef.com,
(403) 269-3158.
