Final Blog: The Empty Quarter's Unique Landscape

In the Empty Quarter, there are five types of sand landscapes that look wonderful. Each one was created because of different climatic and location factors. What make Empty Quarter amazing are the types of sand dunes, amount of water, and the ancient city.

The first type is Barchan dunes, these dunes are located in the Northeastern part of the area, and they can reach around 150-200 meters (492.12-656 ft) in height. Also, it often contains moist "sabkha" that interspread among the Barchan dunes (The Empty Quarter). Sabkah is a crusty surface, flat area between a desert and the sea. Also, it contains salt, gypsum, and calcium carbonate. It has bow shape because of its movement with the wind.

Figure 1: From looking at the slipface, we know that the wind blows from right to left. Also, the dune moves with the wind, which mean that dune slowly moves from right to left as well.

The second type is Star Dunes; we believe these types of dunes are unique because of their shapes. Also, they have steep paramedic shapes and steep tops. This type of dunes can reach 200 meters (656 ft) in height; they are located in the Southeast of the Empty Quarter (The Empty Quarter).

Figure 2: As shown, the star dune has its unique shape because of the complex wind directions. the wind is blowing almost from every direction.

The third type is Domal Dunes, this type of dunes are located in the middle of the empty quarter and their height usually around 100 meters (328.08 ft) (The Empty Quarter). Also, they are inter-structured. These dunes do not have steep edge because of the complex wind direction and look like domes. According to National Geographic, this kind of dunes are the rarest (Dune).

Figure 3: this kind of dunes do not have slipface.

The fourth type is Longitudinal Dunes, sometimes called "linear" or "Seif" dune; this dunes spread between the Southwestern and the Northeastern part of the Empty Quarter in a parallel formation. Also, it can get up to 100 meters (238.08 ft) (The Empty Quarter). Complex wind directions create star, domal, and longitudinal dunes.

Figure 4: it shows how the dunes are formed parallel to the wind direction. 

The fifth type of landscape is Sand Sheets, this type of landscape looks like a sheet of sand that covers the ground and it includes low hills; this landscape is considered the most flat landscape of the Empty Quarter (The Empty Quarter).

Figure 5: It shows how the flat ground of the desert look like

As everyone knows that the Empty Quarter desert has one of the hardest climates in the world. The climate can reach 61 degrees C. (142 degrees F) and 2% humidity, which is very dry (Wynn, Jeff). Also, the Empty Quarter contains aquifers. From understanding the lakes existence, some water tables are higher than the ground itself, which creates small lakes, thus creating oases. According to McClore’s doctoral thesis at London University about the Empty Quarter, lakes were formed in two separate periods of time. The first lakes were formed 37,000 to 17,000 years ago. And, the second lakes were formed 10,000 to 5,000 years ago (McClure, Harold).

The Empty Quarter got its name because of its emptiness. However, we found it not empty after all. It preserves a whole city under the ground, "Iram of the Pillars" city, which is also named "the Atlantis of the Sand" (Iram Of The Pillars). It is located in the Southwest of the Empty Quarter. We believe that the existent of the city under the sand suggests a second explanation of how the desert was formed in that area. Instead of slow sand transportation, we believe that a massive sand storm "massive Haboob" hit the city all of a sudden and buried the entire city.

Future Prediction:

We believe that after 1,000 years, rock decaying will happen to the surrounding mountains, which will transport more sand from the mountains to the desert. Also, the hight of the mountains might decrease measurably, but the changes will be detected by the naked eye. After 10,000, we believe that the vegetation will extend from Salala (city in Oman, which is located southeastern of the Empty Quarter) to the Empty Quarter covering up to half of the Empty Quarter. Also, the vegetation will grow from Salala toward the Northwest up to the middle of the Empty Quarter. We believe that rock decaying will affect mountains to a degree, that the naked eye will be able to notice the changes. After 1,000,000 years, we believe that the vegetation will cover the Empty Quarter and the water tables will rise, creating more lakes. Also, we predict that mountains near the Red Sea will decay during those years. Chances are that  a river will be formed, it could extend from the starting point at Oman, going throw the empty quarter to the Red Sea. The mountains that surround the desert, on the other hand, might become small to medium sized hills because of rock decaying. The Arabian peninsula could move closer to Iran, thus increasing the size of the Red Sea. Some of the sand dunes will become petrified (sand dunes that got solidified), before the time when vegetation covers the entire empty quarter.

Figure 6: This is an example of a Petrified sand dunes from Arches National Park.

                                                                                                                                              
References:

"Dune." National Geographic Education. Web. 07 May 2013. <http://education.nationalgeographic.com/education/encyclopedia/dune/?ar_a=1>

"Iram Of The Pillars: The Atlantis Of The Sands." Explorers Journal. N.p., 20 Nov. 2012. Web. 07 May 2013. <http://www.explorers-journal.com/iram-of-the-pillars-the-atlantis-of-the-sands/>.

McClure, Harold.”Late Quaternary Palaeoenvironments of the Rub’ al Khali.” PhD thesis, University of London. 1984. 07 May 2013

"The Empty Quarter." Saudi Geological Survey. Web. 07 May 2013. <http://www.sgs.org.sa/english/earth/pages/emptyquarter.aspx>.

Wynn, Jeff. "The Empty Quarter Expeditions." The Wynn Family Organization.Web. 07 May 2013. <http://www.wynn.org/EmptyQuarter/>.

Figure 1: http://www.schweich.com/imagehtml/dunebarchan.html

Figure 2: http://www.environmentalatlas.ae/geographicInheritance/dunesAndSabkha

Figure 3: http://www.sgs.org.sa/english/earth/pages/emptyquarter.aspx

Figure 4: http://www.handsontheland.org/grsa/resources/curriculum/mid/dunes/photo_files/longitudinal.htm

Figure 5: http://www.sgs.org.sa/english/earth/pages/emptyquarter.aspx

Figure 6: http://members.virtualtourist.com/m/p/m/68cb3/

Blog #3: Water Tables of the Empty Quarter

Water Tables of the Empty Quarter

The Empty Quarter has been known over the years for its richness of water tables. Its perfect location has given it a great amount of “water tables” which is water stored underneath the ground. Crossroad Arabia website has noted that there is about 4 billion cubic meter of water which is about 141 trillion cubic feet (Tapping the Empty Quarter’s Water). Over millions of years the water has been building up in this area until recently, when they discovered that this amount of water could be used throughout the country.
                                            Figure 1:

Figure 1 shows that excess water from rain is stored underground.

The Empty Quarter has two Water tables. First one is in the south west of Saudi Arabia, near Yaman's borders is the only water pump in the Empty Quarter which serves the entire southern part of Saudi Arabia. Najran City governor in the south west side of Saudi Arabia opened this pump in 2004. The pump is connected to 17 wells, that pumps around 50,000 cubic meters of water on a daily basis (Tapping the Empty Quarter’s Water).
                                            Figure 2:

Figure 2 shows how people extract water from water tables using wells.

Second water table is located in the middle of the Empty Quarter and where the climate could get up to 126 F (Bates, Brainerd S.). The existence of oases in this location and this temperature fascinates us. Oases occur because of high level water table that are located in between of two high grounds, which gather the water in one place to create a lake.  

                                          Figure 3:

Figure 3 shows how water tables are connected to rivers and lakes.

                                           Figure 4:

Figure 4 is a picture of an Oasis at the Empty Quarter.

The entire Quarter does not get much of rain each year. In addition, the Empty Quarter is bounded by mountains and heights all around, mountains are located in the south of Saudi Arabia and North of Oman. Najd plateau is up in the north of it and Sarawat mountains from the west. Most of the water comes from these heights and settle in it. As we studied in Physical Geography class, this type of water called gravity water because it moves with gravity and sinks into the ground through unsaturated zone (also called aeration zone, which is a zone above the water table and below surface where air and water reserve in microscopic spaces) until it reaches and reserves in the saturated zone (it is a zone below unsaturated zone where only water reserve in the microscopic spaces). We think that since the entire Arabia peninsula is surrounded by water then its ground is saturated which made the Empty Quarter reserve and store the water.

                          
                                          Figure 5:

Figure 5 shows the difference between saturated and unsaturated zones and how water table is located between unsaturated and saturated zones. Under the saturated zone is called an aquifer, which is like a warehouse of water and the saturated zone is holding the aquifer from reaching to the unsaturated zone (Aquifers).

References 

1- "Aquifers." United States Geological Survey. N.p., n.d. Web. 17 Apr. 2013. <http://ga.water.usgs.gov/edu/earthgwaquifer.html>.

2- Bates, Brainerd S. "Camping In The Empty Quarter." Saudi Aramco World. N.p., n.d. Web. 17 Apr. 2013. <http://www.saudiaramcoworld.com/issue/196706/camping.in.the.empty.quarter.htm>.

3- "Tapping the Empty Quarter’s Water." Crossroads Arabia. N.p., 02 Apr. 2011. Web. 17 Apr. 2013 <http://xrdarabia.org/2011/04/02/tapping-the-empty-quarters-water/>.


Images
1- Figure 1 and 2: http://myweb.cwpost.liu.edu/vdivener/notes/groundwater.htm
2- Figure 3: http://water.usgs.gov/ogw/karst/kigconference/ns_comparisons.htm
3- Figure 5: http://ga.water.usgs.gov/edu/earthgwaquifer.html
4- Figure 4: http://www.shutterstock.com/pic-41129995/stock-photo-an-oasis-in-the-oman-desert.html

Blog #2: Weathering Processes of The Empty Quarter

Weathering Processes of The Empty Quarter

Mountain decay (weathering) is one of the two causes that created the Empty Quarter. The best guess is that physical weathering processes (the changes that happen to the earth surface) decayed the rocks of the mountains that surround the Empty Quarter from three sides South, East, and West. We are covering only one mountains range (the Hajar Mountains Range) as an example. From what we understand from Burkhard Bilger’s article, the Hajar Mountains are exposed to salt water and rain for more than sixty five million years. We conclude from this information that physical weathering processes caused the mountains rocks to decay.

Pressure Release Weathering Process:

In our opinion, one of the common weathering processes that happens at that region is pressure release. The process occurs when boulders crack in to smaller boulders or rocks under high pressure, which is called pressure release shells. The rocks are formed by this process have shape of layers.

Western Hajar Mountains Range

Little Snake Canyon in Oman

(The top of the mountain shaped like layers, which seems that these shapes were caused by Prussure Release)

http://catbirdinoman.wordpress.com/category/western-hajar-mountains/

Pressure Root Weathering Process:

We think that the pressure roots weathering process is the second common weathering process on this mountains range. Plants roots grow in the fractures (joints) of the mountains. the roots expand and grow deep in the fractures causing pressure that cracks the mountains' rocks leading to chunk of rocks falling down.

Vegetations grow on the mountains

It shows that plants grow on rocks

http://catbirdinoman.wordpress.com/category/western-hajar-mountains/

Salt Weathering Process:

According to Burkhard Bilger’s article, most weathering caused by salt weathering process. It happens when there is not enough fresh water to wash away the salt. This decaying process happens when the salt crystals stick in the holes and small fractures of rocks. With cooling and heating, the salt crystals expand and shrink in fractures that weaken the rocks, which leads to rocks decay. We think this process can be true, however, we could not trace any pictures with salt crystals to proof that the process have happened.

http://www.newyorker.com/reporting/2011/12/19/111219fa_fact_bilger

Erosion Process:

Erosion process is the process of transporting the substances, such as sand or tiny rocks caused or found by weathering processes, whether by wind or water. After the weathering processes occurred, erosion by water process starts on the top of the mountain. What happens is that rain causes flash floods that wash up the sand down to the wadies (Arabic word for valleys) into the Empty Quarter Basin; where water evaporates, and sand forms the Empty Quarter's sand dunes. 

http://www.sgs.org.sa/english/earth/pages/emptyquarter.aspx

First Blog Assignment: Mountains

The Mountains 

The Hajjar Mountians, Tuwaiq Mountains, and The Arabian Shield are sourounding the Empty quarter, and they are critical reasons of the creation of Empty Quarter.

The Hajjar Mountains

The Hajjar Mountains are located in the East side of the Empty Quarter basin. These mountains are located in Oman and UAE. Understanding the causes that formed mountains that are surrounding the Empty Quarter provide us clearer explanation, because these mountains is the one of the reasons that formed the Empty Quarter.

UAE side of The Hajjar mountains 

The Mountains Formation:

Subduction is the main cause of creating the distinctive geology of the Hajar Mountains. From what we have read, because of the subduction that occurred in the deep of the Tethys Ocean, which have created an obduction on the shore that caused the creation of the Hajar Mountains. What happened was the volcanic activity had pushed the curst causing a subduction in the bottom of the ocean. Because of the subduction in the ocean, a collision took place between a continental crust and an oceanic crust, and this activity called obduction. On the shore, folding and faulting happened, which created the mountains. The formation of the mountains is estimated to be started approximately 90 million years ago and was completed by about 75million years ago. 

Tuwaiq Mountains

Jebel Tuwaiq (Tuwaiq Mountain ) which is around 600 meters high; is one of the interesting geographic landmarks in the Arabian Peninsula. Jebel Tuwaiq is a Plateau of limestone that extends from south of the capital "Riyad" to the north of the empty quarter. 

Road from Riyad to Mekkah, which goes throw Jebel Tuwaiq 

Flash flood at part of Twauiq Mountains

The mountain was named tuwaiq because it extends by 800km and looks like a “tuwq”, which means a collar, so its shaped like “(“.  The mountain is located on upper Jurassic part of KSA, and it has high reserves of oil. Bureau and Saudi Aramco used LIDAR survey to build a 3-D model of the mountain.

Formation of Twauiq Mountain:

 The Arabian Shield

Location Of The Arabian Shield As Shown On the Map

                                             

Najid Plateau

                                                              

The studies showed that in 1770 Ma the subduction process between three micro-plates Zalm, the Kabid, and southern Afif terrain have created what’s called the Arabian Shield. Arabian shield is formation of several mountains and Najid Plateau. The Kabid micro-plate formation is the oldest one of these terrains which goes back to Proterozoic. By 720 Ma Afif Southern Micro-plate collided with Asir terrain as part of the Nabitah orogeny. According to the studies, faulting was the process that caused formation of Najid plateau. Najid Strike-Slip fault has changed the its motion direction. 

1-The Hajar mountians Citations:

http://www.uaeinteract.com/uaeint_misc/teanh/005over.pdf

http://pollock-virag.com/UAE/2008_Sandy_Beach/Sandy_Beach_2008.htm

2-Twaiq Mountains Citations:

http://www.beg.utexas.edu/resprog/worldwide/ilris_saudiarabia.htm
Book: Sedimentary Basins and Petroleum Geology of the Middle East, By A.E.M. Nairn, A.S. Alsharhan


3- The Arabian Shield formation Article citation:

http://looklex.com/e.o/najd.htm

http://jgs.lyellcollection.org/content/142/6/1189.short