Journal Article Review: East Africa's Great Rift Valley

I. Introduction

Considered a geologic marvel, the East African Rift Valley has confounded geologists and has emerged as a site for exploration to understand the geologic processes that cause rifts and other land formations to occur. Much debate amongst geophysicists and geologists regarding how the rifts in Africa formed has persisted, and the existence of eastern and western rifts has only complicated the issue of rift formation ("East Africa's Great Rift Valley: A Complex Rift System"). Twenty-five million years ago, plate tectonics pulled land on the African continent apart and formed a valley where the Nubian and Somalian plates have separated from the Arabian plate. The eastern rift valley stretches from Ethiopia to the developing area of Kenya, while its western counterpart passes through Uganda and Malawi ("East African Rift Gets a New Birth Date," 2012). Although two separate rifts exist with divergent characteristics, scientists believe that they still possess genetic similarities due to their proximity to one another. Ultimately, the East African Rift System helps scientists today understand the geologic processes that undergird plate tectonics, which results in continents breaking apart.

II. Brief Overview and Main Points

In this article, James Wood and Alex Guth discuss the general geological characteristics that define rifts in Africa as well as the geologic processes that contributed to their formation. Currently, new plates in Africa have been forming which has created new rifts across the African continent. Geologists and geophysicists alike continue to debate the precise geologic processes that cause rifts to form. Many point to continental heating and volcanic eruptions as the central contributor to rift formation. The East African Rift system provides a modern case study for scientists to further analyze what causes rifting.

Rifting in East Africa has confounded geologists because of the existence of two separate branches: the western rift includes the African Great Lakes while the eastern branch is located approximately 600 kilometers east, with Lake Victoria located in the middle of them. The authors compare and contrast the rift in Kenya with the one in Ethiopia to explain why scientists separate them despite genetic similarities ("East Africa's Great Rift Valley: A Complex Rift System"). The Eastern Rift is characterized by high volcanicity while volcanic activity is restricted in the West, which renders the Eastern Rift as possessing more geothermic potential (Saemundsson, 2010). The Western Rift has greater earthquake activity and contains large lakes within the deep basins and high sedimentation.

The East African Rift fascinates scientists because, unlike rifts in other areas of the world, it still is accessible for scientists to directly study the processes that underlay rifting in the modern-day. Other rifts have progressed so much that they have submerged underwater or are too filled with sedimentation. Moreover, scholars have pointed to the East African Rift as the etiology of the human race, as they have found fossils of hominids in the region. The formation of the rift most likely altered climate conditions and contributed to human adaptation and evolution to the shifting conditions. Thus, it should be closely studied by all geologists and scientists to understand the foundation of human evolution ("East Africa's Great Rift Valley: A Complex Rift System").

III. Article Strengths

Wood and Guth provide a clear and concise overview of rifting in Africa and why the East Africa Rift System has relevance towards the understanding of geologic processes as well as the roots of human evolution. The accessibility of the East Africa Rift, unlike other rifts in the world submerged underwater or filled with sediments, renders it a perfect site for scientists to study and understand plate tectonics and continental formation both past and present. Wood and Guth effectively and precisely explained geologic processes in a manner that made the information tangible and comprehensible for people who do not possess a wide range of knowledge about geology.

IV. Article Weaknesses

Although Wood and Guth provide a concise and informative argument, more detail would have enhanced and fulfilled the purpose of this article. The connection between the roots of human evolution and studying the rifts could have been expounded upon. Many of the points they make are purely speculative, as the authors fail to validate their claims with scientific facts.

V. Conclusion

The East African Rift System and other rifts located in Africa continue to marvel scientists and have sparked debates within the geologic and geophysical community regarding what mechanisms precisely cause rifting to occur. The East Africa Rift System has become a vital site for scientific investigation because unlike other rifts throughout the world, scientists can directly access and study it. Moreover, hominid fossils have been found in the region, which has prompted scientists and scholars to study the region to understand the roots of human evolution. Although informative and concise, much of the article speculates about rifting and its implications about human evolution rather than firmly discussing the scientific debate about the geologic processes involved in the formation of rifts.

References

Gammon, C. (2012, March 30). First Humans' African Home Gets New Birth Date. LiveScience. Retrieved April 9, 2014, from http://www.livescience.com/19381-african-rift-older-formation.html

Saemundsson, K. (n.d.). EAST AFRICAN RIFT SYSTEM - AN OVERVIEW. Exploration for Geothermal Resources. Retrieved April 6, 2014, from http://www.os.is/gogn/unu-gtp-sc/UNU-GTP-SC-11-18.pdf

Wood, J., & Guth, A. (n.d.). East Africa's Great Rift Valley: A Complex Rift System. East Africa's Great Rift Valley: A Complex Rift System. Retrieved April 9, 2014, from http://geology.com/articles/east-africa-rift.shtml