Field Trips
Register early—attendance for the field trips is limited and passes will be issued on a
first‑come, first-served basis.
Wadi Jizzi Ophiolites, Oman
Monday, 3 December 2007 ● 0600-1900 hours
Fee: USD375 per person - includes field trip guidebook, breakfast snack, lunch, transportation by four-wheel-drive vehicles from and back to meeting point Dubai World Trade Centre, visa cost upon entry and exit from borders.
Leader: Jan Schreurs, Petroleum Development Oman
Pillow Graves Geotimes, Wadi Jizzi
Wadi Jizzi is one of the main east-west valleys (wadis) that cross the northern Oman mountains. It is an ancient route between the Gulf and the oases of Buraimi at the Omani-UAE border. This is an area famous for its copper ore, mined since times immemorial. Wadi Jizzi is also famous for its magnificent outcrops of the Samail Ophiolites, notably the highest volcanic succession of the ophiolites, which will be the focus of this field excursion.
Sohar Peak, the most prominent landmark
in the Wadi Jizzi area
This is also the area that has been identified as the legendary land of Magan, known from Sumerian texts from Ur in Mesopotamia, as far back as the reign of king Argon, some 4400 years ago, referring to cargoes of copper and diorite from this country.
Archaeological findings also point to trade connections with early civilisations in the Indus valley. Some 30 places where copper has been minded and melted have been found in this wadi, centred around Aarja.
The Semail Ophiolite is the largest and best exposed fragment of oceanic lithosphere found on land in the world. Not surprisingly these rocks have been the focus of many studies since their first detailed description by Geologists of the Shell Group (Glennie et al., 1974). They provide a unique opportunity to study the anatomy of the oceanic crust. From the coast in the east crossing into the mountains westward one passes along basalts with pillow lavas and even the occasional ‘black smokers’; the sulphide vents found at mid-oceanic ridges. The horizontal traverse westwards takes you deeper into the oceanic crust even passing the Moho – the compositional boundary between the crust and mantle and on into the upper mantle.
Sabkha - Modern Carbonate-Evaporite Depositional Environments of Abu Dhabi, U.A.E.
Sponsored by Abu Dhabi Co. for Onshore Oil Operations
Monday, 3 December 2007 ● 0700-1800 hours
Fee: USD60 per person - includes field trip guidebook, breakfast snack, lunch, transportation by four-wheel-drive vehicles from and back to meeting point in Dubai World Trade Centre.
Leaders: Abdulla Al-Mansoori, Omar Al-Jeelani, Ismail Al-Hosani, Ali Al-Shamry and Christian Strohmenger, Abu Dhabi Co. for Onshore Oil Operations; Khalil Al-Mehsin, Abu Dhabi Natl. Oil Co.; Hesham Shebl, Zakum Development Co.
The modern carbonate-evaporite depositional environments along the Abu Dhabi shoreline and offshore Abu Dhabi belong to the few areas of the world where the geoscientist can observe the interplay between carbonate and evaporite sedimentation.
The analysis of modern analogs is one of the few means by which high-resolution spatial complexity of stratigraphic systems can be described. If the horizontal dimensions of facies belts are less than the typical well spacing, modern analogs, together with seismic and production data help to construct realistic geologic and simulation models of subsurface reservoirs.
Supratidal (sabkha) to intertidal (microbial mat), and lowermost intertidal to shallow subtidal (lagoon: skeletal-peloid tidal-flat) environments will be studied along the Abu Dhabi coastline at Mussafah Industrial Channel and in the vicinity of Al-Qanatir Island.
Mussafah Channel
The trench is actually the wall of a man-made shipping canal cut into the sabkha near the Mussafah Industrial Area. The canal wall reveals a few meters of vertical sabkha succession. Excellent exposures of classic sabkha anhydrite occur as nodular to highly contorted bands.
Al-Qanatir Island
In the vicinity of the road to Al-Qanatir Island participants will be able to study a complete and undisturbed lateral facies succession of the upper supratidal to the shallow subtidal environments:
- Upper supratidal stranded beach ridges.
- Topographic highs, some cm above the adjacent upper sabkha environment.
- Upper sabkha (upper supratidal).
- Surface covered by polygonally-cracked halite crust.
- Middle sabkha (middle supratidal).
- Surface covered by finely-crystalline, whitish anhydrite polygons.
- Lower sabkha (lower supratidal).
- Surface covered by shiny, sparkling gypsum crystals.
- Upper to lower intertidal microbial mat.
- Crenulated or crinkled microbial mat above gypsum mush facies.
- Blistered and pinnacle microbial mat.
- Polygonal and tufted microbial mat.
- Lowermost intertidal to shallow subtidal.
- Peloid-skeletal tidal-flat.
Many of these depositional environments and facies successions correspond to those observed in cores from the subsurface of the Arabian Peninsula.
