Fakta mengejutkan muncul pada awal Agustus 2010. Tim peneliti berhasil menguak misteri selat Bosphorus[1] dengan bantuan teknologi robotic yang menampilkan pencitraan tiga dimensi terhadap kondisi di dasar selat.
Selat yang menghubungkan Laut Hitam dan Laut Marmara ini memiliki karakteristik unik, permukaan airnya mengalir dari utara ke selatan disebabkan level air di permukaan Laut Hitam lebih tinggi dibanding level air Laut Marmara, sementara di dasar selat yang kedalamannya bervariasi antara 30-60 meter mengalir sungai bawah laut ke arah utara menuju Laut Hitam.
Sungai bawah laut ini memiliki ciri yang identik dengan lokasi ujung barat yang disebutkan dalam kisah ekspedisi Dzulqarnain. Sebelumnya saya berpendapat bahwa “ainin hami’at” yang disebutkan dalam kisah ekspedisi tersebut adalah Laut Hitam, dan memperkirakan lokasi ekspedisi pertama ini berada di pesisir timurnya. Namun mengacu pada teks ayat yang menyebut “ain” (mata air/aliran sungai) dan bukannya “bahr” (laut), ternyata fenomena selat Bosphorus lebih mendekati maksud ayat sebenarnya.
Tim ilmuwan yang dipimpin University of Leeds melakukan penelitian aliran sungai bawah laut ini yang mereka perkirakan menjadi sungai terbesar ke-6 di dunia jika posisinya berada di darat. Sungai ini mirip dengan sungai darat, namun alirannya yang deras terbentuk di bawah laut yang berupa campuran pasir, lumpur dan air berkadar garam tinggi sehingga ia melayang dan mengalir di dasar laut.
Aliran sungai bawah laut berlumpur hitam di selat Bosphorus ini sesuai dengan bunyi teks ayat Quran (QS. Al-Kahf, 18:86) berikut ini:
Until, when he reached the setting of the sun, he found it [as if] setting in a spring of dark mud, and he found near it a people. Allah said, "O Dhul-Qarnayn, either you punish [them] or else adopt among them [a way of] goodness."
Hingga apabila dia telah sampai ketempat terbenam matahari, dia melihat matahari terbenam di dalam laut yang berlumpur hitam, dan dia mendapati di situ segolongan umat. Kami berkata: "Hai Dzulkarnain, kamu boleh menyiksa atau boleh berbuat kebaikan terhadap mereka.
Terjemah bahasa Inggris versi Sahih International di atas lebih tepat menterjemahkan kata “ainin hami’at” sebagai “a spring of dark mud” (mata air/aliran sungai berlumpur hitam). Terjemah versi lain menyebutkan “laut” dikarenakan mereka mengidentifikasinya sebagai Laut Hitam. Sebenarnya ini tidak salah secara total karena memang lumpur hitam yang mengalir di bawah Selat Bosphorus juga masuk ke Laut Hitam. Namun setiap ayat Quran didesain oleh Allah menggunakan kalimat yang sangat tepat dan penuh makna. Kata “ainin hami’at” mempunyai arti mata air atau aliran sungai berlumpur hitam, sementara istilah laut biasanya disebut menggunakan kata “bahr”.
Sungai bawah laut ini, menurut Dr. Daniel Parsons yang memimpin project penelitian, berasal dari Laut Mediterania yang memiliki kandungan garam lebih tinggi dibanding Laut Hitam. Air berkadar garam tinggi dari Laut Mediterania melayang di dasar laut dan membentuk semacam saluran yang tidak bercampur dengan air di atasnya, membawa serta lapisan sedimen lumpur hitam bercampur pasir, mengalir menuju Laut Hitam melalui Laut Aegean dan Laut Marmara dan kemudian melewati selat Bosphorus.
Aliran lumpur hitam ini terjadi terus-menerus disebabkan posisi permukaan Laut Hitam lebih tinggi dibanding permukaan Laut Marmara dan Laut Mediterania di sebelah selatannya, sedangkan Laut Hitam sendiri terus terisi dengan suplai air tawar dari sungai Danube yang mengalir dari dataran Eropa, dan berbagai sungai lain di sekitarnya. Akibatnya, kadar garam air di Laut Hitam selalu lebih rendah, dan aliran sungai bawah laut yang membawa lumpur akan terus memasuki Laut Hitam.
Dalam publikasinya, website Livescience.com[2] menampilkan foto skesta sungai raksasa bawah laut ini yang berhasil dibuat menggunakan instrument robotic Yellow Submarine.
Gambar selanjutnya di bawah ini adalah hasil pencitraan satelit dan aerial view selat Bosphorus yang menghubungkan Laut Hitam dengan Laut Marmara di sebelah barat Turki. Di bawah selat inilah mengalir sungai bawah laut yang mengalirkan campuran pasir, lumpur hitam dan air.
Dari hasil kajian ini kita bisa memperoleh gambaran lokasi ekspedisi awal Dzulqarnain yang disebutkan dalam Surah Al-Kahf (QS. 18:86). Lokasinya bukanlah berada di pesisir timur Laut Hitam sebagaimana pendapat saya sebelumnya, namun lebih tepat di sebelah selatan Laut Hitam, yakni di selat Bosphorus.
Memang terdapat banyak pendapat tentang identifikasi lokasi ekspedisi pertama Dzulqarnain ini. Ada yang berpendapat Laut Hitam, ada yang meyakini Laut Mediterania, bahkan ada yang berpendapat lokasinya adalah ujung barat benua Afrika yakni di Samudera Atlantik. Sejak masa ulama salaf hingga khalaf, mereka memiliki pendapat dengan hujjahnya masing-masing. Lalu, pendapat yang mana yang benar? Wallahu a’lam, hanya Allah yang Mengetahui kebenaran sesungguhnya. Namun berbagai clue yang disebutkan dalam kitab suci-Nya akan membimbing kita untuk menemukan kebenaran atau paling tidak pendapat kita akan lebih mendekati kebenaran.
Jika identifikasi lokasi ini benar, maka untuk menentukan siapa sebenarnya Dzulqarnain kita tinggal menelusuri berbagai catatan sejarah tentang seorang penguasa dari timur yang melebarkan daerah kekuasaannya hingga wilayah Bosphorus ini.
Memang terdapat banyak pendapat tentang identifikasi lokasi ekspedisi pertama Dzulqarnain ini. Ada yang berpendapat Laut Hitam, ada yang meyakini Laut Mediterania, bahkan ada yang berpendapat lokasinya adalah ujung barat benua Afrika yakni di Samudera Atlantik. Sejak masa ulama salaf hingga khalaf, mereka memiliki pendapat dengan hujjahnya masing-masing. Lalu, pendapat yang mana yang benar? Wallahu a’lam, hanya Allah yang Mengetahui kebenaran sesungguhnya. Namun berbagai clue yang disebutkan dalam kitab suci-Nya akan membimbing kita untuk menemukan kebenaran atau paling tidak pendapat kita akan lebih mendekati kebenaran.
Jika identifikasi lokasi ini benar, maka untuk menentukan siapa sebenarnya Dzulqarnain kita tinggal menelusuri berbagai catatan sejarah tentang seorang penguasa dari timur yang melebarkan daerah kekuasaannya hingga wilayah Bosphorus ini.
[1]
Publikasi hasil penelitian tim ilmuwan yang dipimpin oleh University of Leeds.
Berikut saya copas semua artikelnya yang terdapat dalam website berikut:
Publikasi aslinya di website University of Leeds telah
dihapus.
Leeds researchers study
undersea rivers with a yellow submarine
August 2, 2010 - via
University of Leeds
A team of scientists led by
the University of Leeds has used a robotic ‘yellow submarine’ to observe
detailed flows within an ‘undersea river’ for the very first time.
The researchers estimate that the river - known as a submarine channel - would be the sixth largest river in the world if it were on land based on the amount of water flowing through it.
Submarine channels are similar to land rivers, but they are formed by density currents - underwater flow mixtures of sand, mud and water that are denser than sea water and so sink and flow along the bottom.
These channels are the main transport pathway for sediments to the deep sea where they form sedimentary deposits. These deposits ultimately hold not only untapped reserves of gas and oil, they also house important secrets - from clues on past climate change to the ways in which mountains were formed.
Now the team, led by Dr Dan Parsons and Dr Jeff Peakall from the University of Leeds, has been able to study the detailed flow within these channels. Dr Parsons, said: "The channel complex and the density flow provide the ideal natural laboratory for investigating and detailing the structure of the flow field through the channel.
"Our initial findings show that the flow in these channels is quite different to the flow in river channels on land. Specifically as flow moves around a bend it spirals in the opposite direction in the deep sea compared to the spiral to that found in river channels on land. This is important in understanding the sedimentology and layers of sediment deposited by these systems."
It is thought by some that the channels in the Black Sea were formed around 6,000 years ago when sea levels were approaching their current point. The Mediterranean swelled and breached through into the Black Sea - once an isolated freshwater lake - via the Bosphorus Strait. As the waters surged, they carried a dense, salty fluid which formed a network of sea-floor channels that are almost constantly active, even today.
Some people even believe that this was the biblical event Noah's flood, but despite their historical significance, the first spectacular images of these submarine channels were only obtained in 2006 (by researchers at Memorial University, Newfoundland, Canada who are project partners in this study).
Submarine channels are notoriously difficult to study because of their power and unpredictability. In the past they have been known to destroy scientific equipment and as a consequence most existing knowledge about them has been obtained from small scale laboratory measurements and from examples of past channels now exposed on dry land.
To tackle this problem, the team used the Natural Environment Research Council's (NERC) Autosub3 - a 7-metre torpedo-shaped robot - to get up close and personal with the sea-floor. Because it has an accurate positioning system, the sub can be programmed to stay just above the channels - safe from damage.
The team will use the data obtained to create innovative computer simulations that can be used to model how sediment flows through these channels. The models the team will produce will have broad applications, including inputting into the design of seafloor engineering by oil and gas companies.
The project was led by Dr Jeff Peakall and Dr Daniel Parsons at the University of Leeds in collaboration with the University of Southampton, Memorial University (Newfoundland, Canada), and the Institute of Marine Sciences (Izmir, Turkey). The survey was run and coordinated from the Institute of Marine Sciences Research Ship, the R/V Koca Piri Reis.
The researchers estimate that the river - known as a submarine channel - would be the sixth largest river in the world if it were on land based on the amount of water flowing through it.
Submarine channels are similar to land rivers, but they are formed by density currents - underwater flow mixtures of sand, mud and water that are denser than sea water and so sink and flow along the bottom.
These channels are the main transport pathway for sediments to the deep sea where they form sedimentary deposits. These deposits ultimately hold not only untapped reserves of gas and oil, they also house important secrets - from clues on past climate change to the ways in which mountains were formed.
Now the team, led by Dr Dan Parsons and Dr Jeff Peakall from the University of Leeds, has been able to study the detailed flow within these channels. Dr Parsons, said: "The channel complex and the density flow provide the ideal natural laboratory for investigating and detailing the structure of the flow field through the channel.
"Our initial findings show that the flow in these channels is quite different to the flow in river channels on land. Specifically as flow moves around a bend it spirals in the opposite direction in the deep sea compared to the spiral to that found in river channels on land. This is important in understanding the sedimentology and layers of sediment deposited by these systems."
It is thought by some that the channels in the Black Sea were formed around 6,000 years ago when sea levels were approaching their current point. The Mediterranean swelled and breached through into the Black Sea - once an isolated freshwater lake - via the Bosphorus Strait. As the waters surged, they carried a dense, salty fluid which formed a network of sea-floor channels that are almost constantly active, even today.
Some people even believe that this was the biblical event Noah's flood, but despite their historical significance, the first spectacular images of these submarine channels were only obtained in 2006 (by researchers at Memorial University, Newfoundland, Canada who are project partners in this study).
Submarine channels are notoriously difficult to study because of their power and unpredictability. In the past they have been known to destroy scientific equipment and as a consequence most existing knowledge about them has been obtained from small scale laboratory measurements and from examples of past channels now exposed on dry land.
To tackle this problem, the team used the Natural Environment Research Council's (NERC) Autosub3 - a 7-metre torpedo-shaped robot - to get up close and personal with the sea-floor. Because it has an accurate positioning system, the sub can be programmed to stay just above the channels - safe from damage.
The team will use the data obtained to create innovative computer simulations that can be used to model how sediment flows through these channels. The models the team will produce will have broad applications, including inputting into the design of seafloor engineering by oil and gas companies.
The project was led by Dr Jeff Peakall and Dr Daniel Parsons at the University of Leeds in collaboration with the University of Southampton, Memorial University (Newfoundland, Canada), and the Institute of Marine Sciences (Izmir, Turkey). The survey was run and coordinated from the Institute of Marine Sciences Research Ship, the R/V Koca Piri Reis.
A vast river flowing along
the ocean floor has been sketched out for the first time using a robotic
submarine.
Researchers estimate that
this "undersea river" known as a submarine channel would be the
sixth largest river in the world if it were located on land, based on
the amount of water flowing through it.
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