Latest news from PESA QLD President:
Please be advised that today’s AGM and technical lunch will proceed. Given the weather and predictions, we will start AGM proceedings without any delay from 12.15pm, to ensure we can be finished the meeting before 1.30pm to allow attendees to head home before the forecast worst of the weather. Please ensure that if you are travelling to today’s lunch, that you carefully consider your circumstances and safety, and whether it is appropriate to attend.
PESA Queensland President
PESA QLD is very pleased to have secured Dr Mark Tingay to present a QLD technical lunch session whilst he is here in Brisbane teaching his Geomechanics short course. This last-minute change means that Mr Henk van Paridon’s technical lunch which was initially scheduled for this day, will be delayed until later in the year. Dr Tingay is a world renowned Geomechanics and Tectonics expert, and PESA QLD is very pleased to have been able to secure his availability to present to our members.
For those interested to learn more about Dr Tingay’s Geomechanics and Pore Presure Prediction short course, details can be found at the PESA QLD bookings website HERE. Bookings for the short course are filling up, so please don’t hesitate to secure your spot.
Topic: The 2016 Australian Stress Map:
Implications For Petroleum Exploration & Production
Speaker: Dr. Mark Tingay
Venue: Royal on the Park Hotel, Cnr Alice and Albert Streets, Brisbane QLD 4000
Date & Time: 30th March 2017, 12:15 pm
Knowledge of the present-day stress field is essential in petroleum geomechanics applications such as the stability of boreholes; assessing fault reactivation and associated seal breach, and; improving production through natural and induced fractures. The World Stress Map (WSM) Project has, for over 25 years, compiled a global database of present-day tectonic stress information to determine and understand the state of stress in the Earth’s lithosphere. The latest versions of both the World Stress Map Project and Australian Stress Map Project were released in late 2016, with the WSM now containing >41000 stress indicators, including >2200 stress indicators from 30 provinces in Australia.
The WSM database has revealed that plate-scale stress fields are controlled by forces exerted at plate boundaries (e.g. mid-ocean ridges, continental collision zones), commonly resulting in regional stress orientations sub-parallel to plate motion. However, the present-day stress field at smaller scales, such as within sedimentary basins, remains poorly understood in comparison. Detailed analysis of present-day stresses from over 90 sedimentary basins reveals that significant and complex variations in the present-day stress orientation are commonly observed at both basin (10-200 km) and field (0.1-10 km) scales. For example, the North German Basin, Molasse Basin, Nile Delta and the Baram Delta province of northwest Borneo indicate broad regional rotations in the horizontal stress orientation at the basin scale. The North Sea, Gulf of Mexico, Gulf of Thailand, Nile Delta, Clarence-Morton and Surat Basins (NE Australia), and Permian Basin of Texas all host examples of sharply varying stress orientations at the field and well scale. Such localised stress rotations have significant petroleum implications, as the stability of wells, direction of induced hydraulic fractures and reactivation risk of faults may vary greatly, even within a single field or well.
This study presents a wide range of examples of stress patterns observed in sedimentary basins, and highlights the geological factors controlling the state of stress in sedimentary basins. Basin- and reservoir-scale stress fields result from the complex interaction of numerous factors acting at different scales, including far-field forces (e.g. plate boundary forces), basin geometry (e.g. the shape of deltaic wedges), geological structures (e.g. diapirs, faults), mechanical contrasts (e.g. evaporites, overpressured shales, detachment zones), surface and sub-surface topography and deglaciation. The lessons learned from the WSM project dataset, combined with knowledge of a region’s geology and tectonic setting, can be used to forecast expected basin-scale stress patterns, and predict whether (and where) localized stress rotations are likely to be observed.
The PESA QLD Branch Annual General Meeting (AGM) will be held before the commencement of the technical talk.
Attendees of Dr Tingay’s Geomechanics and Pore Pressure Prediction course will automatically be booked in for this Technical Lunch.