Abstract Mineralogical, geochemical and the potentiality of source shale rocks in the Khabour For... more Abstract Mineralogical, geochemical and the potentiality of source shale rocks in the Khabour Formation from the Akkas-1 well, western Iraq and the Chia Zinnar section exposed in extreme northern Iraq were studied. Whole rock minerals observed are quartz, feldspars (labradorite, albite and orthoclase), pyrite and rare calcite. The main clay minerals observed in the studied shales are illite, chlorite, kaolinite, and mixed layer illite. SEM analysis shows that kaolinite is typically present as hexagonal plates and booklets, some of which are degraded, illite is commonly present as fibers and fine white flakes. Mixed layer illite is commonly observed as framboidal shapes while chlorite is observed as disc-shaped chlorite. Two samples from the upper, Hirnantian, part of the Akkas-1 well exhibit great differences from post Archean Australian shale (PAAS) in both major and trace element geochemistry. This is in contrast to the 13 other samples from the Akkas-1 well which have a trace element composition very close to PAAS. These differences are hard to interpret but they may record the impact of the Hirnantian glaciation. Common redox indicators (Th/U, Cu/Zn, V/Rb, Mn) all suggest an oxic environmental conditions prevailed during deposition of the Khabour Formation in the Akkas-1 well; this is supported by low TOC values. Khabour shales from the Akkas-1 well are organically lean (TOC 0.04–0.84%) and are late to post mature for oil generation. They represent poor sedimentary organic matter (SOM) but the presence of bitumen in the samples suggest source rocks do exist in this part of the succession. The studied samples from the Chia Zinnar section (extreme northern Iraq) are organically lean (TOC
Geological Society, London, Special Publications, 2017
Obtaining estimates of the rates of sedimentation and frequency of depositional events at high re... more Obtaining estimates of the rates of sedimentation and frequency of depositional events at high resolution from pre-Quaternary successions is rarely possible, particularly in coarse-grained clastic successions of continental basin margins. In the Miocene strata of the Ebro Basin, northern Spain, basin-marginal deposits interpreted as the products of alluvial fans are part of the continuous aggradational fill of a basin of internal drainage. A palaeomagnetic reversal stratigraphy has been established in basin-centre sediments and correlation across to the basin margin makes it possible to estimate the rate of aggradation within the fan successions to be 90 mm ka−1. The deposits of one alluvial fan near the village of Linás de Marcuello have been analysed in the context of these rates to provide estimates of the frequency of depositional events. This analysis suggests that deposition on gravel bars approximately 700 mm thick in stream channel deposits occurred at intervals of 70–200 ye...
This is a quick and simple oil exploration and production game for students doing a short course ... more This is a quick and simple oil exploration and production game for students doing a short course in petroleum geology. Students, working in groups as ‘companies’ make decisions on where to explore, how much to invest in exploration and when and where to drill wells. In the production phase, the current oil price determines the profitability of some fields. The game is run by the instructor using a BASIC computer program on a microcomputer. The program generates the results of exploration from data sets, keeps track of the state of exploration in all the areas and prepares financial statements. The game is designed to be played by a group of students in a single lab/practical session of two to three hours.
Abstract Mineralogical, geochemical and the potentiality of source shale rocks in the Khabour For... more Abstract Mineralogical, geochemical and the potentiality of source shale rocks in the Khabour Formation from the Akkas-1 well, western Iraq and the Chia Zinnar section exposed in extreme northern Iraq were studied. Whole rock minerals observed are quartz, feldspars (labradorite, albite and orthoclase), pyrite and rare calcite. The main clay minerals observed in the studied shales are illite, chlorite, kaolinite, and mixed layer illite. SEM analysis shows that kaolinite is typically present as hexagonal plates and booklets, some of which are degraded, illite is commonly present as fibers and fine white flakes. Mixed layer illite is commonly observed as framboidal shapes while chlorite is observed as disc-shaped chlorite. Two samples from the upper, Hirnantian, part of the Akkas-1 well exhibit great differences from post Archean Australian shale (PAAS) in both major and trace element geochemistry. This is in contrast to the 13 other samples from the Akkas-1 well which have a trace element composition very close to PAAS. These differences are hard to interpret but they may record the impact of the Hirnantian glaciation. Common redox indicators (Th/U, Cu/Zn, V/Rb, Mn) all suggest an oxic environmental conditions prevailed during deposition of the Khabour Formation in the Akkas-1 well; this is supported by low TOC values. Khabour shales from the Akkas-1 well are organically lean (TOC 0.04–0.84%) and are late to post mature for oil generation. They represent poor sedimentary organic matter (SOM) but the presence of bitumen in the samples suggest source rocks do exist in this part of the succession. The studied samples from the Chia Zinnar section (extreme northern Iraq) are organically lean (TOC
Geological Society, London, Special Publications, 2017
Obtaining estimates of the rates of sedimentation and frequency of depositional events at high re... more Obtaining estimates of the rates of sedimentation and frequency of depositional events at high resolution from pre-Quaternary successions is rarely possible, particularly in coarse-grained clastic successions of continental basin margins. In the Miocene strata of the Ebro Basin, northern Spain, basin-marginal deposits interpreted as the products of alluvial fans are part of the continuous aggradational fill of a basin of internal drainage. A palaeomagnetic reversal stratigraphy has been established in basin-centre sediments and correlation across to the basin margin makes it possible to estimate the rate of aggradation within the fan successions to be 90 mm ka−1. The deposits of one alluvial fan near the village of Linás de Marcuello have been analysed in the context of these rates to provide estimates of the frequency of depositional events. This analysis suggests that deposition on gravel bars approximately 700 mm thick in stream channel deposits occurred at intervals of 70–200 ye...
This is a quick and simple oil exploration and production game for students doing a short course ... more This is a quick and simple oil exploration and production game for students doing a short course in petroleum geology. Students, working in groups as ‘companies’ make decisions on where to explore, how much to invest in exploration and when and where to drill wells. In the production phase, the current oil price determines the profitability of some fields. The game is run by the instructor using a BASIC computer program on a microcomputer. The program generates the results of exploration from data sets, keeps track of the state of exploration in all the areas and prepares financial statements. The game is designed to be played by a group of students in a single lab/practical session of two to three hours.
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