Geology of Abu Dhabi: 150m High Dune Ridges & Evaporitic Flats - Essay Sample

Introduction

The geology of Abu Dhabi lies under dune ridges which is approximately 150m high inland. The evaporitic flats, sabkhas take over the coastal plains and stretches to the south into the sand deserts for a distance that exceeds 80 km. To the west is an area known as Al Ain, a place where all the projections in Abu Dhabi are enclosed, and the part of the region formed by the Oman Mountains. Jabal Hafit is a very key projection and is well known for taking over a marine that ranges all the way from the ages of the Lower Eocene to Oligocene or the Rupelian in Al Ain city. Besides, there are some other two key projections taking over the age of the marine from upper Cretaceous/Campanian to Upper Eocene, and are known as Jabal Mundassa, and Jabal Malaqet (Alsharhan, & Kendall, 2019).

Is your time best spent reading someone else’s essay? Get a 100% original essay FROM A CERTIFIED WRITER!

Save 25%

Kharaib Formation

This is a formation that respites with a very negligible inconsistency upon the Lekhwair creation. Besides, it poses a circular pattern of carbonate sedimentation portrayed in the creation of Lekhwair. The Lime-mudstone and wackestone represents the cyclic Trangessive, while packstone and grainstone represents cyclic regressive. The ruling cyclic regressive and cyclic transgressive often distinguishes this formation from both the lower Lekhwair, and Lekhwair formation respectively.

Porosity

This is the process of weighing out the volumes of the pore to the volume of bulk rock and is often expressed as a percentage. According to Rice, (2017), Mesoporous materials are those that are having pores with diameters ranging from 2 to 50nm, based on IUPAC nomenclature, and according to it, a material with pores that their diameter falls below 2 nm, is known as a microporous material, and a material possessing a pore with the diameter greater than 50nm known as a macroporous material.

The Volumes of Macropore, Mesopore, and Micropore Determined through Gas Adsorption and MICP Techniques*

Sample N2 and CO2 Adsorption** Hg Intrusion

In soil, this is a hole that is known to have a diameter greater than 75mm, and assists in a preferable flow of soil solution, frequent solute transportation, and colloids. They allow improvement of soil hydraulic conductivity, facilitating a quick water infiltration, drainage, and a relatively rapid movement of shallow groundwater via a lateral flow. The aggregation of soil particles into peds, plant roots, soil fauna, and soil cracks leads to macropore formation in the soil. The types of macropores are primary pore which is defined as the predominant reservoir hole present in the volcanic cones, which includes intergranular pores. This type of primary pore is commonly found in volcanic rock, specifically volcanic breccias, and occurs due to the volume between the rock grains whereas, the intragranular which is also a type of a primary pore, occurs due to the presence of spaces within the grains of rock (Zhu, et al. 2016)

The Evolution of Diagenesis, and origin of MacroporesDiagenesis based on Laurent et al. (2016), is a process that takes place between metamorphism, and deposit formation due to high pressure, and temperature. It also contains some tiny processes like trace element migration, creation of micropores, and comparison of stable isotopes. The following are the types of diagenesis that exists; cementation, consisting of a process that facilitates precipitation of the minerals both in secondary, and primary pores, and super saturation which depends on the required mineral. Since cementation is a type of destructive diagenesis, it is therefore a very important factor in diagenesis. The initial diagenetic cementation results to a lowered primary porosity. Another type of diagenesis is compaction, and it is different at Jia-2 member of the southern Puguang gasfield, whereby some places are strong, feeble, and might be similar to the distinguishing feature in the sedimentary fabrication of the carbonate rocks. Places with strong compaction are almost the same to lenticular, and augen. Lastly, dissolution which majorly fosters the formation of effective reservoir

Diagenetic origin of macroporesThe porosity formation occurring in carbonate rocks contains some patterns which have stressed a meteoric diagenesis attendant which is not deep and contains a subaerial exposure. Besides, the creation of porosity takes place in mesogenic, or deep-buria due to the stretching of already available pores through dissolution and formation of a new system of pores. The masogenetic dissolution is created by fluids such as carbon dioxide, hydrogen sulphide obtained from organic matter diagenesis, the reduction of thermochemical sulfate, and organic acids. Facilitated and newly formed mesogenic types of pores have the potential of mimicking the types of pores created in areas with small depths, and this may lead lack of recognition of other porosity due to mesogenetic (Hollis, et al. 2017). Rudstone is amongst the types of carbonate rock, grainstone is a type of carbonate rock which is grain-supported with a mud grade material of less than one percent, and a packstone is a carbonate rock which is grain supported with more-mud grade fraction (Hattori, Loucks, & Kerans, 2019).

Reference

Alsharhan, A. S., & Kendall, C. S. C. (2019). Interpretations of Holocene Carbonate-Evaporites of Coastal and Inland Sabkhas of Abu Dhabi (United Arab Emirates) from Landsat Satellite Images and Field Survey. In Sabkha Ecosystems (pp. 151-187). Springer, Cham.

Hattori, K. E., Loucks, R. G., & Kerans, C. (2019). Stratal architecture of a halokinetically controlled patch reef complex and implications for reservoir quality: A case study from the Aptian James Limestone in the Fairway Field, East Texas Basin. Sedimentary Geology, 387, 87-103.

Hollis, C., Lawrence, D., Darmaki, F. A., Perriere, M. D. D., Foote, A., & Kostic, B. (2017, November). Origin of Complex Carbonate Pore Systems and Associated Reservoir Quality Variations: an Example From the Arab Formation Upper Jurassic, Onshore United Arab Emirates. In Abu Dhabi International Petroleum Exhibition & Conference. Society of Petroleum Engineers.

Laurent, G. C., Edoardo, P., Ian, S. R., Peacock, D. C. P., Roger, S., Ragnar, P., ... & Vladimir, M. (2016). Origin and diagenetic evolution of gypsum and microbialitic carbonates in the Late Sag of the Namibe Basin (SW Angola). Sedimentary Geology, 342, 133-153.

Rice, R. W. (2017). Porosity of ceramics: properties and applications. CRC Press.Zhu, C., Liu, T., Qian, F., Han, T. Y. J., Duoss, E. B., Kuntz, J. D., ... & Li, Y. (2016). Supercapacitors based on three-dimensional hierarchical graphene aerogels with periodic macropores. Nano Letters, 16(6), 3448-3456.