أزمة ملوحة العصر المسيني

التفسير الفني لجغرافيا المتوسط خلال عملية السحب التبخيري، بعد اكتمال الانقطاع عن الأطلسي. حفرت الأنهار وديان عميقة في الحواف القارية المكشوفة؛ أدى تركيز الملح في المسطحات المائية المتبقية إلى هطول سريع. حفز الاقتحام عبور الثدييات (مثل الجمال والجرذان) من أفريقيا إلى أيبريا عبر مضيق جبل طارق المكشوف.
الأحداث الرئيسية في العصر النيوجيني
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حدث المسيني[1]
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الهولوسيني يبدأ 11.7 م.س.م.
مقياس زمني تقريبي للأحداث الرئيسية للعصر النيوجيني.
المحور الرئيسي: بالمليون سنة.

أزمة ملوحة العصر المسيني Messinian Salinity Crisis (MSC)، وتعرف أيضاً بحدث المسيني Messinian Event، وفي مرحلتها المتأخرة تُعرف بحدث لاگو مير Lago Mare، كان حدثاً جيولوجياً دخل أثناؤها البحر المتوسط في دورة كاملة أو شبه كاملة من التجفف طوال الجزء الأخير من العصر المسيني ضمن فترة الميوسين، من 5.96 إلى 5.33 سنة مضت (مليون سنة مضت). انتهت بالفيضان الزانكلي، عندما غمرت مياه الأطلسي الحوض.[2][3]

عينات الرواسب التي جُمعت من القاع العميق في البحر المتوسط، والتي تحتوي على معادن متبخرات، تربة، ونباتات أحفورية، تظهر أن مضيق جبل طارق كان مغلقاً بإحكام منذ حوالي 5.96 مليون سنة مضت، فاصلاً البحر المتوسط عن المحيط الأطلسي. أسفر هذا عن فترة من التجفف الجزئي للبحر المتوسط، أولى الفترات المماثلة التي حدثت في أواخر العصر الميوسيني.[4] بعد انغلاق المضيق آخر مرة منذ حوالي 5.6 مليون سنة مضت، تسبب المناخ الجاف بصفة عامة في المنطقة، في ذلك الوقت، في تجفيف حوض المتوسط، العملية التي اكتملت في فترة تقارب الألف عام. ترك هذا التجفيف الكبير حوضاً جافاً عميقاً، يصل عمقه لحوالي 3-6 كم أسفل مستوى سطح البحر الطبيعي، مع جيوب أجاج (مفرطة الملوحة) مشابهة للبحر الميت الحالي. بعد ذلك، منذ حوالي 5.5 مليون سنة مضت، أسفرت الظروف المناخية الأقل جفافاً في تلقي الحوض المزيد من المياه العذبة من الأنهار، وامتلأ الحوض تدريجياً وتحولت البحيرات الأجاج إلى جيوب أكبر من الماء المويلح (أي أقل ملوحة من الأجاج (الأكثر شبهاً ببحر قزوين المعاصر). انتهت أزمة ملوحة العصر المسيني بانفراج جبل طارق في النهاية منذ 5.33 مليون سنة مضت، عندما ملأ المحيط الأطلسي بشكل سريع حوض المتوسط فيما يعرف بالفيضان الزانكلي.[5]

حتى اليوم، يعتبر البحر المتوسط أكثر ملوحة عن المحيط الأطلسي لأنه منفصل تقريبياً بمضيق جبل طارق وبسبب ارتفاع معدل البخر. إذا انغلق مضيق جبل طارق مرة أخرى (والذي من المرجح حدوثه في المستقبل القريب على مقياس الزمن الجيولوجي)، فسوف تتبخر معظم مياه البحر المتوسط في حوالي ألف سنة، بعدها ستستمر أفريقيا في التحرك شمالاً حتى تطمس البحر المتوسط تماماً.

في الوقت الحالي لا يحافظ على مستوى البحر المتوسط الحالي سوى تدفق مياه المحيط الأطلسي. عندما كان مغلقاً في وقت ما بين 6.5- 6 مليون سنة مضت، كان صافي الخسارة الناتجة عن البخر حوالي 300.3 كيلومتر مكعب سنوياً. بهذا المعدل، فإن 3.7 مليون كيلومتر مكعب من المياه في الحوض ستجف في أكثر من ألف عام، تاركة طبقة كبيرة من الملح يصل سمكها لعشرات الأمتار ومؤدية لارتفاع مستوى البحر عالمياً لحوالي 12 متر.[6]

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Naming and first evidence

In the 19th century, the Swiss geologist and paleontologist Karl Mayer-Eymar (1826–1907) studied fossils embedded between gypsum-bearing, brackish, and freshwater sediment layers, and identified them as having been deposited just before the end of the Miocene Epoch. In 1867, he named the period the Messinian after the city of Messina in Sicily, Italy.[7] Since then, several other salt-rich and gypsum-rich evaporite layers throughout the Mediterranean region have been dated to the same period.[8]


الأدلة الإضافية والتأكد

Seismic surveying of the Mediterranean basin in 1961 revealed a geological feature some 100–200 m (330–660 ft) below the seafloor. This feature, dubbed the M reflector, closely followed the contours of the present seafloor, suggesting that it was laid down evenly and consistently at some point in the past. The origin of this layer was largely interpreted as related to salt deposition. However, different interpretations were proposed for the age of salt and its deposition.

Earlier suggestions from Denizot in 1952[9] and Ruggieri in 1967[10] proposed that this layer was of Late Miocene age, and the same Ruggieri coined the term Messinian Salinity Crisis.

New and high-quality seismic data on the M-reflector were acquired in the Mediterranean Basin in 1970.[11] At the same time, the salt was cored during Leg 13 of the Deep Sea Drilling Program conducted from the Glomar Challenger under the supervision of co-chief scientists William B.F. Ryan and Kenneth J. Hsu. These deposits were dated and interpreted for the first time as deep-basin products of the Messinian salinity crisis.

أقماع الجبس، والتي تشكلت على سطح البحر نتيجة للتبخر. تبخر متر واحد من مياه البحر يسهم بتكون حوالي 1 مم من الجبس.
مقياس تشكل الجبس في سورباس. تشير المخاريط المتنامية لأعلى إلى هطول على قاع البحر (وليس داخل الرواسب)

The first drilling of the Messinian salt at the deeper parts of the Mediterranean Sea came in the summer of 1970, when geologists aboard the Glomar Challenger brought up drill cores containing arroyo gravels and red and green floodplain silts; and gypsum, anhydrite, rock salt, and various other evaporite minerals that often form from drying of brine or seawater, including in a few places potash, left where the last bitter, mineral-rich waters dried up. One drill core contained a wind-blown cross-bedded deposit of deep-sea foraminiferal ooze that had dried into dust and been blown about on the hot dry abyssal plain by sandstorms, mixed with quartz sand blown in from nearby continents, and ended up in a brine lake interbedded between two layers of halite. These layers alternated with layers containing marine fossils, indicating a succession of drying and flooding periods.

The massive presence of salt does not require a desiccation of the sea.[12] The main evidence for the evaporative drawdown of the Mediterranean comes from the remains of many (now submerged) canyons that were cut into the sides of the dry Mediterranean basin by rivers flowing down to the abyssal plain.[13][14] For example, the Nile cut its bed down to 200 metres (660 feet) below sea level at Aswan (where Ivan S. Chumakov found marine Pliocene Foraminifera in 1967), and 2,500 m (8,200 ft) below sea level just north of Cairo.[15]

In many places in the Mediterranean, fossilized cracks have been found where muddy sediment had dried and cracked in the sunlight and drought. In the Western Mediterranean series, the presence of pelagic oozes interbedded within the evaporites suggests that the area was repeatedly flooded and desiccated over 700,000 years.[16]

A possible palaeogeographical reconstruction of the west end of the Miocene Mediterranean. North to the left.
  current coastline
S Sorbas basin, Spain
R Rifean corridor
B Betic corridor
G Strait of Gibraltar
M Mediterranean sea

Based on palaeomagnetic datings of Messinian deposits that have since been brought above sea level by tectonic activity, the salinity crisis started at the same time over all the Mediterranean basin, at 5.96 ± 0.02 million years ago. This episode comprises the second part of what is called the "Messinian" age of the Miocene epoch. This age was characterised by several stages of tectonic activity and sea level fluctuations, as well as erosional and depositional events, all more or less interrelated (van Dijk et al., 1998).[17]

The Mediterranean-Atlantic strait closed tight time and time again, and the Mediterranean Sea, for the first time and then repeatedly, partially desiccated. The basin was finally isolated from the Atlantic Ocean for a longer period, between 5.59 and 5.33 million years ago, resulting in a large or smaller (depending on the scientific model applied) lowering of the Mediterranean sea level. During the initial, very dry stages (5.6–5.5 Ma), there was extensive erosion, creating several huge canyon systems[13][14] (some similar in scale to the Grand Canyon) around the Mediterranean. Later stages (5.50–5.33 Ma) are marked by cyclic evaporite deposition into a large "lake-sea" basin ("Lago Mare" event).

About 5.33 million years ago, at the start of the Zanclean age (at the start of the Pliocene epoch), the barrier at the Strait of Gibraltar broke one last time, re-flooding the Mediterranean basin in the Zanclean flood;[18][19] favouring slope destabilization.[20] The basin has not desiccated since.

Several cycles

The amount of Messinian salts has been estimated as around 4×1018 kg (but this estimate may be reduced by 50 to 75% when more information becomes available[21]) and more than 1 million cubic kilometres,[22] 50 times the amount of salt normally in the Mediterranean waters. This suggests either a succession of desiccations or a long period of hypersalinity during which incoming water from the Atlantic Ocean was evaporated with the level of the Mediterranean brine being similar to that of the Atlantic. The nature of the strata points strongly to several cycles of the Mediterranean Sea completely drying and being refilled (Gargani and Rigollet, 2007[4]), with drying periods correlating to periods of cooler global temperatures; which were therefore drier in the Mediterranean region.[بحاجة لمصدر] Each refilling was presumably caused by a seawater inlet opening, either tectonically, or by a river flowing eastwards below sea level into the "Mediterranean Sink" cutting its valley head back west until it let the sea in, similarly to a river capture. The last refilling was at the Miocene/Pliocene boundary, when the Strait of Gibraltar broke wide open permanently.[19] Upon closely examining the Hole 124 core, Kenneth J. Hsu found that:

The oldest sediment of each cycle was either deposited in a deep sea or in a great brackish lake. The fine sediments deposited on a quiet or deep bottom had perfectly even lamination. As the basin was drying up and the water depth decreased, lamination became more irregular on account of increasing wave agitation. Stromatolite was formed then, when the site of deposition fell within an intertidal zone. The intertidal flat was eventually exposed by the final desiccation, at which time anhydrite was precipitated by saline ground water underlying sabkhas. Suddenly seawater would spill over the Strait of Gibraltar, or there would be an unusual influx of brackish water from the eastern European lake. The Balearic abyssal plain would then again be under water. The chicken-wire anhydrite would thus be abruptly buried under the fine muds brought in by the next deluge. [23]

Research since then has suggested that the desiccation-flooding cycle may have repeated several times[24][25] during the last 630,000 years of the Miocene epoch. This could explain the large amount of salt deposited. Recent studies, however, show that the repeated desiccation and flooding is unlikely from a geodynamic point of view.[26][27]

Synchronism versus diachronism—deep water versus shallow water evaporites

Hypotheses of evaporite formation during the MSC.
a: Diachronous deposition: Evaporites (pink) were deposited in landward basins first, and closer to the Atlantic as the extent of the Mediterranean Sea (dark blue) diminished towards the gateway. The light blue shows the original sea level.
b: Synchronous deposition in marginal basins. Sea level drops slightly, but the whole basin is still connected to the Atlantic. Reduced inflow allows the accumulation of evaporites in shallow basins only.
c: Synchronous, basin-wide deposition. Closure or restriction of the Atlantic seaway by tectonic activity (dark grey) causes evaporite deposition simultaneously across the entire basin; the basin may not need to empty completely, as salts are concentrated by evaporation.

Some major questions remain concerning the beginning of the crisis in the central Mediterranean Basin. The geometric physical link between the evaporitic series identified in marginal basins accessible for field studies, such as the Tabernas Desert and Sorbas Basin, and the evaporitic series of the central basins has never been made.

Using the concept of deposition in both shallow and deep basins during the Messinian (i.e. assuming that both Basin types existed during this period), two major groupings are evident: one that favours a synchronous deposition (image c) of the first evaporites in all the basins before the major phase of erosion;[28] and the other that favours a diachronous deposition (image a) of the evaporites through more than one phases of desiccation which would first have affected the marginal basins and later the central basins.[5]

Another school suggests that desiccation was synchronous, but occurred mainly in shallower basins. This model would suggest that the sea level of the whole Mediterranean basin fell at once, but only shallower basins dried out enough to deposit salt beds. See image b.

As highlighted in the work of van Dijk (1992)[29] and van Dijk et al. (1998)[17] the history of desiccation and erosion was complexly interacting with tectonic uplift and subsidence events, and erosional episodes. They also questioned again like some previous authors had done, whether the basins now observed as "deep" were actually also deep during the Messinian Episode and gave different names to the end-member scenarios described above.

Distinguishing between these hypotheses requires the calibration of gypsum deposits. Gypsum is the first salt (calcium sulphate) to be deposited from a desiccating basin. Magnetostratigraphy offers a broad constraint on timing, but no fine detail. Therefore, cyclostratigraphy is relied upon to compare the dates of sediments. The typical case study compares the gypsum evaporites in the main Mediterranean basin with those of the Sorbas basin, a smaller basin on the flanks of the Mediterranean Sea that is now exposed in southern Spain. The relationship between these two basins is assumed to represent the relationships of the wider region.

Recent work has relied on cyclostratigraphy to correlate the underlying marl beds, which appear to have given way to gypsum at exactly the same time in both basins.[30]

The proponents of this hypothesis claim that cyclic variations in bed compositions are astronomically tuned, and the beds' magnitude can be calibrated to show they were contemporaneous—a strong argument. In order to refute it, it is necessary to propose an alternative mechanism for generating these cyclic bands, or for erosion to have coincidentally removed just the right amount of sediment everywhere before the gypsum was deposited. The proponents claim that the gypsum was deposited directly above the correlated marl layers, and slumped into them, giving the appearance of an unconformable contact.[30] However, their opponents seize upon this apparent inconformity, and claim that the Sorbas Basin was exposed—therefore eroding—while the Mediterranean sea was depositing evaporites. This would result in the Sorbas Basin being filled with evaporites at 5.5 million years ago (Ma), compared to the main basin at 5.96 Ma.[31][32]).

Recent works have highlighted a pre-evaporite phase corresponding to a prominent erosional crisis (also named "Messinian erosional crisis"; the termination of the "Mes-1" unconformity bound depositional sequence of van Dijk, 1992)[29] responding to a major drawdown of the Mediterranean seawater.[33]

Assuming that this major drawdown corresponds to the major Messinian drawdown, they concluded that the Mediterranean bathymetry significantly decreased before the precipitation of central basins evaporites. Regarding these works, a deep water formation seems unlikely. The assumption that central basin evaporites partly deposited under a high bathymetry and before the major phase of erosion should imply the observation of a major detritic event above evaporites in the basin. Such a depositional geometry has not been observed on data. This theory corresponds to one of the end-member scenarios discussed by van Dijk et al.[17]


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Causes

Several possible causes of the series of Messinian crises have been considered. While there is disagreement on all fronts, the most general consensus seems to agree that climate had a role in forcing the periodic filling and emptying of the basins, and that tectonic factors must have played a part in controlling the height of the sills restricting flow between the Atlantic and Mediterranean.[34] The magnitude and extent of these effects, however, is widely open to interpretation (see, e.g., van Dijk et al. (1998).[17]

In any case, the causes of the closing and isolation of the Mediterranean Sea from the Atlantic Ocean must be found in the area where the Strait of Gibraltar is now. One of the tectonic boundaries between the African Plate and the European Plate and its southern fragments such as the Iberian Plate is there. This boundary zone is characterised by an arc-shaped tectonic feature, the Gibraltar Arc, which includes southern Spain and northern Africa. In the present day area of the Mediterranean Sea, are three of these arc-shaped belts: the Gibraltar Arc, the Calabrian Arc, and the Aegean Arc. The kinematics and dynamics of this plate boundary and of the Gibraltar Arc during the late Miocene are strictly related to the causes of the Messinian salinity crisis: tectonic reconfiguration may have closed and re-opened passages, as the region where the connection with the Atlantic Ocean was situated is permeated by strike-slip faults and rotating blocks of continental crust. As faulting accommodated the regional compression caused by Africa's convergence with Eurasia, the geography of the region may have altered enough to open and close seaways. However, the precise tectonic activity behind the motion can be interpreted in a number of ways.[35]

Any model must explain a variety of features of the area:

  • Shortening and extension occur at the same time in close proximity; sedimentary sequences and their relations to fault activity constrain the rates of uplift and subsidence quite precisely
  • Fault-bounded continental blocks can often be observed to rotate
  • The depth and structure of the lithosphere is constrained by records of seismic activity, as well as tomography
  • The composition of igneous rocks varies—this constrains the location and extent of any subduction.

There are three contending geodynamic models that may fit the data, models which have been discussed in an equal way for the other arc shaped features in the Mediterranean:[36]

  • A moving subduction zone may have caused periodic regional uplift. Changes in volcanic rocks suggest that subduction zones at the rim of the Tethys Sea may have rolled back westwards, changing the chemistry and density in magma underlying the western Mediterranean.[37] However, this does not account for the periodic emptying and refilling of the basin.
  • The same features can be explained by regional delamination[38] or the loss of a layer of the entire lithosphere.[39]
  • Deblobbing, the loss of a "blob" of lithospheric mantle, and the subsequent upward motion of the overlying crust (which has lost its dense mantle "anchor") may also have caused the observed phenomena[40] although the validity of the "deblobbing" hypothesis has been called into question.[41]

Of these, only the first model, invoking rollback, seems to explain the rotations observed. However, it is difficult to fit it with the pressure and temperature histories of some metamorphic rocks.[42]

This has led to some interesting combinations of the models which at first hand looked bizarre, in attempts to approach the true state of affairs.[43][44]

Changes in climate must almost certainly be invoked to explain the periodic nature of the events. They occur during cool periods of Milankovic cycles, when less solar energy reached the northern hemisphere. This led to less evaporation of the North Atlantic, hence less rainfall over the Mediterranean. This would have starved the basin of water supply from rivers and allowed its desiccation.[بحاجة لمصدر]

Glacioeustatic sea level falls with an amplitude of around 10 metres (33 ft) that began approximately 6.14 Ma were likely responsible for modulating the connection between the Mediterranean and the Atlantic. One particularly major glacioeustatic fluctuation, a sea level drop of about 30 metres (98 ft), occurred around 5.26 Ma, around the Miocene-Pliocene boundary.[45]

Relationship to climate

The climate of the abyssal plain during the drought is unknown. There is no situation on Earth directly comparable to the dry Mediterranean, and thus it is not possible to know its climate by direct observation of comparable geographic settings. Simulation using a general circulation model can indicate physically consistent responses to the desiccation.[46] There is no consensus as to whether the Mediterranean Sea dried out completely; it seems likeliest that at least three or four large brine lakes on the abyssal plains remained at all times. The extent of desiccation is very hard to judge, owing to the reflective seismic nature of the salt beds, and the difficulty in drilling cores, making it difficult to map their thickness.

Atmospheric forces can be studied to arrive at a speculation on the climate. As winds blew across the "Mediterranean Sink", they would heat or cool adiabatically with altitude. In the empty Mediterranean Basin, the summertime temperatures would probably have been extremely high. As a first approximation, using the dry adiabatic lapse rate of around 10 °C (18 °F) per kilometer, the maximum possible temperature of an area 4 km (2.5 mi) below sea level would be about 40 °C (72 °F) warmer than it would be at sea level. Under this extreme assumption, maxima would be near 80 °C (176 °F) at the lowest points of the dry abyssal plain, permitting no permanent life but extremophiles. Further, the altitude 3–5 km (2–3 mi) below sea level would result in 1.45 to 1.71 atm (1102 to 1300 mmHg) air pressure, further increasing heat stress. However, these simple estimates are likely far too extreme. Murphy et al.'s 2009 general circulation model experiments[46] showed that for completely desiccated conditions, the Mediterranean basin would warm by up to 15 °C (27 °F) in summer and 4 °C (7.2 °F) in winter, while for a depressed water surface, temperatures would warm by only about 4 °C (7.2 °F) in summer and 5 °C (9.0 °F) in winter. In addition, the model results indicated global stationary wave response to the introduction of the topographic depression causes patters of warming and cooling by up to 4 °C (7.2 °F) around the Northern Hemisphere.

Today the evaporation from the Mediterranean Sea supplies moisture that falls in frontal storms, but without such moisture, the Mediterranean climate that we associate with Italy, Greece, and the Levant would be limited to the Iberian Peninsula and the western Maghreb. Climates throughout the central and eastern basin of the Mediterranean and surrounding regions to the north and east would have been drier even above modern sea level. The eastern Alps, the Balkans, and the Hungarian plain would also be much drier than they are today, even if the westerlies prevailed as they do now.[بحاجة لمصدر] However, the Paratethys ocean provided water to the area north of the Mediterranean basin. The Wallachian-Pontic and Hungarian basins were underwater during the Miocene, modifying the climate of what is now the Balkans and other areas north of the Mediterranean basin. The Pannonian Sea was a source of water north of the Mediterranean basin until the middle Pleistocene before becoming the Hungarian plain. Debate exists whether the waters of the Wallachian-Pontic basin (and the possibly connected Pannonian Sea) would have had access (thus bringing water) to at least the eastern Mediterranean basin at times during the Miocene.

التأثير

الآثار على الأحياء

صورة متحركة لأزمة ملوحة العصر المسيني

كما وفر حدث المسيني الفرصة للكثير من الأنواع الأفريقية، منها الظباء، الفيلة وأفراس النهر، للهجرة إلى الحوض الفارغ، بالقرب من الأنهار العظيمة الهابطة، للوصول إلى المرتفعات الداخلية الأكثر رطوبة وبرودة مثل مالطا حيث كان مستوى سطح البحر يتناقص، من ثم لن تتمكن مثل هذه الأنواع من عبور الحوض الفارغ الساخن في أقصى درجات الجفاف.[بحاجة لمصدر] بعد عودة مياه البحر، ظلت هذه الانواع على الجزر، حيث عانت من التقزم الجزيري أثناء العصر الپلایستوسيني كما حدث على جزيرة كريت (لفرس النهر الكريتي)، وعلى جزيرة قبرص (لفرس النهر القبرصي القزم)، وفي مالطا (لفرس النهر المالطي) وصقلية (لفرس النهر الصقلي)[بحاجة لمصدر]. من بين هذه الأنواع، ظل فرص النهر القبرصي القزم حياً حتى نهاية العصر الپلایستوسيني أو أوائل الهليوسيني.[47][48] لكن بعض هذه الأنواع عبرت البحر عندما فاضت مياهه، وجرفتها المياه على طوافات من النباتات الطافية، أو كما حدث مع بعض الأنواع (مثل الفيلة) عن طريق السباحة.


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الآثار العالمية

كان لابد أن يعاد توزيع المياه الآتية من المتوسط في محيطات العالم، رافعة مستوى سطح البحر بمقدار 10 متر..[بحاجة لمصدر] كما احتبس حوض المتوسط في قاعه نسبة كبيرة من الملح من محيطات العالم؛ أدى هذا لتناقص متوسط الملوحة في محيطات العالم وارتفاع نقطة تجمدها.[49]

جغرافيا الجفاف

اعادة انشاء جغرافي قديم محتمل للحافة الغربية من المتوسط الميوسيني. يقع الشمال على يسار. .
  الشريط الساحلي الحالي.
Sحوض سورباس، إسپانيا
Rالممر الريفي
B الممر البتيكي
G جبل طارق
M البحر المتوسط

فكرة البحر المتوسط الخالي بالكامل من المياه لها بعض الآثار المباشرة.

  • في ذلك الوقت، لم يكن مضيق جبل طارق مفتوحاً، لكن كان هناك طرق مائية أخرى (الممر البتيكي إلى الشمال حيث سييرا نڤادا أو الكوردييرا البايتيكية حالياً، أو إلى الجنوب حيث الممر الريفي أو الممرات التي تقع فيها جبال الريف]] حالياً) تصل البحر المتوسط بالمحيط الأطلسي. ولابد أن هذه الممرات قد غُلقت، مما غزل الحوض عن المحيط المفتوح.
  • مستوى الملوحة المرتفع لا يمكن للكثير من العضيات المعروفة تحمله، العامل الذي أسهم في انخفاض التنوع الحيوي لمعظم الحوض.
  • الارتفاع المنخفض للحوض جعله حاراً للغاية في فصل الصيف عن طريق التسخيص الكظوم، الاستنتاج الذي يؤيده وجود الأنهيدريت، مما حافظ على دفء المياه بدرجات حرارة تزيد عن 35°س.[50][51]
  • الأنهار التي تصب في الحوض كان لابد أن تصل بقاعها لعمق أكبر (2400 متر على الأقل في حالة النيل، حيث يظهر ذلك من خلال الوادي المدفون تحت القاهرة)[52][53] and in the Rhone valley (Gargani, 2004).[54]

معاودة الملء

المقالة الرئيسية: الفيضان الزانكلي

عندما تصدع جبل طارق في نهاية المطاف، صب المحيط الأطلسي كميات ضخمة من المياه من خلال قناة مفترضة ضيقة نسبياً. يتصور أن معاودة الملء هذه كانت نتيجة لشلال ضخم أعلى من شلالات أنجل الحالية بارتفاع 979 م، وأكثر قوة من شلالات إگوازو أو حتى شلالات نياگرا، لكن الدراسات الأخيرة للبنى الموجودة أسفل مضيق جبل طارق أظهرت أن تدفق قناة الفيضان كانت تنحدر في مسار تدريجي نحو البحر المتوسط الجاف.[19]

في الثقافة الشعبية

كانت هناك تكهنات حول احتمال جفاف البحر المتوسط في الماضي البعيد، حتى قبل تطور الجيولوجيا.

  • في القرن الأول، روى پليني الأكبر قصة شعبية في كتابه التاريخ الطبيعي تبعاً لهذه الرواية، تكون البحر المتوسط عندما سُمح للميط الأطلسي بالمرور عبر جبل طارق:

عند الجزء الضيق من المضائق، هناك جبال قد وضعت لتشكل حواجز لمنع الدخول على الجانبين، أبيلا في أفريقيا، وكالپى في أوروپا، الحدود السابقة لأعمال هرقل. ولهذا السبب أطلق عليه السكان اسم أعمدة الرب؛ كما كانوا يعتقدون أن تلك الأعمدة غرستها الآلهة؛ والتي كانت تحول دون مرور البحر، حتى حصل على اذن، ومن ثم تغير وجه الطبيعة.[55]

  • خريطة ولز التكهنية من العشرينيات لما كان قبل 50.000 سنة مضت.

عام 1920، نشر هـ. ج. ولز كتاب تاريخ شعبي اقترح فيه أن حوض المتوسط كان في الماضي جزءاً من المحيط الأطلسي. ومن الأدلة الفيزيائية على ذلك، قناة جبل طارق العميقة السابقة، والتي تم رصدها. قدر ولز بأن الحوض قد أعيد ملئه في ما بين عام 30.000 و10.000 ق.م.[56] النظرية التي طبعها كانت:[56]

    • في الفترة الجليدية الأخيرة، ذهبت الكثير من مياه المحيط إلى الأغطية الجليدية التي أدت لانخفاض مستوى محيطات العالم تحت الحافة في مضيق جبل طارق.
    • بدون التدفق القادم من الأطلسي، كان سيبتخر من البحر المتوسط مياه أكثر من تلك التي يحصل عليها، وسيتبخر وصولاً إلى بحريتين كبرتين، واحدة على البحر البلياري، والأخرى إلى الشرق.
    • ستحصل البحيرة الشرقية على معظم المياه القادمة من النهر، وقد تفيض إلى البحيرة الغربية.
    • ومن المحتمل أن جميع أو بعض من قيعان البحر هذه كانت مأهولة بالبشر، حيث كانت تحصل على المياه من الأنهار القادمة.
    • هناك وادي عميق مغمور يجري من البحر المتوسط وصولاً إلى الأطلسي.
    • أظهرت الأبحاث الحديثة بأن نظرية ولز غير صحيحة. جميع الأدلة الجيولوجية والأحفورية-النباتية تظهر بأن البحر المتوسط لم يجف أثناء العصر الجليدي الأخير. وكانت مستويات سطح البحر أقل 120 متر عن مستوياتها الحالية، مما أدى لضحالة مياه مضيق جبل طارق وانخفاض تبادل المياه مع الأطلسي، لكن لم يكن هناك انقطاع.[57])
  • كما أُشير إلى أتلانتروپا، باسم پانروپا،[58]، كان مشروع للهندسة العملاقة والاستيطان أوصى به المعماير الألماني ÷رمان سورگل في العشرينيات وداع له حتى وفاته عام 1952. كانت السمة المركزية هي السد الكهرومائي الذي أقترح بناؤه عبر مضيق جبل طارق،[59] وتخفيض سطح البحر المتوسط بمقدار 200 م. ظهرت في الخيال مشروعات مشابهة.
  • "شلالات جبل طارق" في قصة دورية الزمن لپول أندرسون عام 1974 وقعت عندما بدء الأطلسي في ملء البحر المتوسط.
  • رواية هاري تورتلدوڤ والتي حملت اسم "الهبوط في الأراضي المنخفضة" وقعت في الأرض البديلة عندما كان البحر المتوسط لا يزال فارغاً، وخالي من المياه، وكان جزء منه عبارة عن منتزه وطني للبلدان المحيطة به، ولم تكن إحداها من البلدان المعروفة في العالم الحقيقي.
  • حلقة "The Vanished Sea" من مسلسل Animal Planet/ORF/ZDF تعرضت للعالم بعد 5 مليون سنة في المستقبل عندما سيجف حوض المتوسط مرة أخرى، ويستكشف أي نوع من الحياة يمكنه البقاء في ظل المناخ الجديد.
  • كتب الخيال العلمي في الثمانينيات والتي حملت اسم The Many-Colored Land وThe Golden Torc، تأليف جوليان ماي، تدور في أوروپا قبل فترة وجيزة وأثناء انفصال جبل طارق. الانفصال والملء السريع للمتوسط شكل ذروة ڤاگنرية لـThe Golden Torc، التي حوصر فيها الغرباء والبشر المسافرون عبر الزمن.
  • دائرة گاندالارا لراندال گارت وڤيكي آن هيدرون أرخت لمغامرات ريكاردو، رجل أرضي معاصر، أُرسل للماضي، حيث اكتشف حضارة كاملة على قاع المتوسط الجاف.
  • رواية السفر عبر الزمن آخر أيام الخلق تأليف ڤولفگانگ جشتك، حدثت منذ 5 مليون سنة، عندما كان قاع المتوسط جافاً.

المصادر

  1. ^ Krijgsman, W.; Garcés, M.; Langereis, C. G.; Daams, R.; Van Dam, J.; Van Der Meulen, A. J.; Agustí, J.; Cabrera, L. (1996). "A new chronology for the middle to late Miocene continental record in Spain". Earth and Planetary Science Letters. 142 (3–4): 367–380. Bibcode:1996E&PSL.142..367K. doi:10.1016/0012-821X(96)00109-4.
  2. ^ Gautier, F., Clauzon, G., Suc, J.P., Cravatte, J., Violanti, D., 1994. Age and duration of the Messinian salinity crisis. C.R. Acad. Sci., Paris (IIA) 318, 1103–1109.
  3. ^ Krijgsman, W (August 1996). "A new chronology for the middle to late Miocene continental record in Spain". Earth and Planetary Science Letters. 142 (3–4): 367–380. doi:10.1016/0012-821X(96)00109-4.
  4. ^ أ ب Gargani J.; Rigollet C. (2007). "Mediterranean Sea level variations during the Messinian Salinity Crisis". Geophysical Research Letters. 34: L10405. Bibcode:2007GeoRL..3410405G. doi:10.1029/2007gl029885.
  5. ^ أ ب Clauzon, Georges; Suc, Jean-Pierre; Gautier, François; Berger, André; Loutre, Marie-France (1996). "Alternate interpretation of the Messinian salinity crisis: Controversy resolved?". Geology. 24 (4): 363. doi:10.1130/0091-7613(1996)024<0363:AIOTMS>2.3.CO;2.
  6. ^ Cloud, P. (1988). Oasis in space. Earth history from the beginning, New York: W.W. Norton & Co. Inc., 440. ISBN 0-393-01952-7
  7. ^ Mayer-Eymar, Karl (1867) Catalogue systématique et descriptif des fossiles des terrains tertiaires qui se trouvent du Musée fédéral de Zürich (Zürich, Switzerland: Librairie Schabelitz, 1867), page 13. From page 13: "Dans ces circonstances, je crois qu'il m'est permis comme créateur d'une classification conséquente et logique de proposer pour l'étage en question un nom qui lui convient en tous points. Ce nom est celui d'Etage messinien." (In these circumstances, I think that I am permitted as the creator of a consistent and logical classification to propose for the stage in question a name that suits it in every way. That name is that of the Messinian stage.)
  8. ^ Kenneth J. Hsu, The Mediterranean Was a Desert, Princeton University Press, Princeton, New Jersey 1983. A Voyage of the Glomar Challenger.
  9. ^ Denizot, G. (1952). Le Pliocène dans la vallée du Rhône. Rev. Geogr. Lyon 27. pp. 327–357.
  10. ^ Ruggieri, G.; Adams, C.J.; Ager, D.V. (1967). "The Miocene and latter evolution of the Mediterranean Sea". Aspects of Tethyan Biogeography. London, England: Systematic Association Publication. p. 283.
  11. ^ Auzende J.M.; Bonnin J.; Olivet J.L.; Pautot G.; Mauffret A. (1971). "Upper Miocene salt layer in the western Mediterranean". Nat. Phys. Sci. 230 (12): 82–84. Bibcode:1971NPhS..230...82A. doi:10.1038/physci230082a0.
  12. ^ Garcia-Castellanos Villaseñor (2011). "Messinian salinity crisis regulated by competing tectonics and erosion at the Gibraltar Arc". Nature. 480 (7377): 359–363. Bibcode:2011Natur.480..359G. doi:10.1038/nature10651. PMID 22170684. S2CID 205227033.
  13. ^ أ ب Gargani J.; Rigollet C; Scarselli S. (2010). "Isostatic response and geomorphological evolution of the Nile valley during the Messinian salinity crisis". Bull. Soc. Géol. Fr. 181: 19–26. doi:10.2113/gssgfbull.181.1.19. S2CID 130839252.
  14. ^ أ ب Gargani J. (2004). "Modelling of the erosion in the Rhone valley during the Messinian crisis (France)". Quaternary International. 121 (1): 13–22. Bibcode:2004QuInt.121...13G. doi:10.1016/j.quaint.2004.01.020.
  15. ^ Warren, J.K. (2006). Evaporites: sediments, resources and hydrocarbons. Birkhäuser. p. 352. ISBN 978-3-540-26011-0.
  16. ^ Wade, B.S.; Brown P.R. (2006). "Calcareous nannofossils in extreme environments: The Messinian Salinity Crisis, Polemi Basin, Cyprus" (PDF). Palaeogeography, Palaeoclimatology, Palaeoecology. 233 (3–4): 271–286. Bibcode:2006PPP...233..271W. doi:10.1016/j.palaeo.2005.10.007.
  17. ^ أ ب ت ث van Dijk, J.P., Barberis, A., Cantarella, G., and Massa, E. (1998); Central Mediterranean Messinian basin evolution. Tectono-eustasy or eustato-tectonics? Annales Tectonicae, 12, n. 1-2, 7-27.
  18. ^ Blanc, P.-L. (2002) The opening of the Plio-Quaternary Gibraltar Strait: assessing the size of a cataclysm. Geodin. Acta, 15, 303–317.
  19. ^ أ ب ت Garcia-Castellanos D.; Estrada F.; Jiménez-Munt I.; Gorini C.; Fernàndez M.; Vergés J.; De Vicente R. (2009). "Catastrophic flood of the Mediterranean after the Messinian salinity crisis". Nature. 462 (7274): 778–781. Bibcode:2009Natur.462..778G. doi:10.1038/nature08555. PMID 20010684. S2CID 205218854.
  20. ^ Gargani J.; F. Bache; G. Jouannic; C. Gorini (2014). "Slope destabilization during the Messinian Salinity Crisis". Geomorphology. 213: 128–138. Bibcode:2014Geomo.213..128G. doi:10.1016/j.geomorph.2013.12.042.
  21. ^ William Ryan (2008). "Modeling the magnitude and timing of evaporative drawdown during the Messinian salinity crisis" (PDF). Stratigraphy. 5 (3–4): 229. Archived from the original (PDF) on 2016-03-04. Retrieved 2014-11-05.
  22. ^ William Ryan (2008). "Decoding the Mediterranean salinity crisis". Sedimentology. 56 (1): 95–136. Bibcode:2009Sedim..56...95R. doi:10.1111/j.1365-3091.2008.01031.x. S2CID 52266741.
  23. ^ Hsu, K.J. (1983). "A Voyage of the Glomar Challenger". The Mediterranean Was a Desert. Princeton, New Jersey: Princeton University Press. ISBN 9780691082936.
  24. ^ Gargani J., Rigollet C. (2007). "Mediterranean Sea level variations during the Messinian Salinity Crisis". Geophysical Research Letters. 34 (L10405): L10405. Bibcode:2007GeoRL..3410405G. doi:10.1029/2007GL029885. S2CID 128771539.
  25. ^ Gargani J.; Moretti I.; Letouzey J. (2008). "Evaporite accumulation during the Messinian Salinity Crisis : The Suez Rift Case" (PDF). Geophysical Research Letters. 35 (2): L02401. Bibcode:2008GeoRL..35.2401G. doi:10.1029/2007gl032494. S2CID 129573384.
  26. ^ Govers, R (2009). "Choking the Mediterranean to dehydration: The Messinian salinity crisis". Geology. 37 (2): 167–170. Bibcode:2009Geo....37..167G. doi:10.1130/G25141A.1.
  27. ^ Garcia-Castellanos, D., A. Villaseñor, 2011. Messinian salinity crisis regulated by competing tectonics and erosion at the Gibraltar Arc. Nature, 2011-12-15 pdf here Link
  28. ^ Krijgsman W.; Hilgen F. J.; Raffi I.; Sierro F. J.; Wilson D. S. (1999). "Chronology, causes and progression of the Messinian salinity crisis". Nature. 400 (6745): 652–655. Bibcode:1999Natur.400..652K. doi:10.1038/23231. hdl:1874/1500. S2CID 4430026.
  29. ^ أ ب van Dijk, J.P. (1992, d); Late Neogene fore-arc basin evolution in the Calabrian Arc (Central Mediterranean). Tectonic sequence stratigraphy and dynamic geohistory. With special reference to the geology of Central Calabria. Geologica Ultrajectina, 92, 288 pp. ISBN 90-71577-46-5
  30. ^ أ ب Krijgsman, W.; Fortuin, A.R.; Hilgen, F.J.; Sierro, F.J. (April 2001). "Astrochronology for the Messinian Sorbas basin (SE Spain) and orbital (precessional) forcing for evaporite cyclicity" (PDF). Sedimentary Geology. 140 (1–2): 43–60. Bibcode:2001SedG..140...43K. doi:10.1016/S0037-0738(00)00171-8. hdl:1874/1632.[dead link]
  31. ^ Riding, R.; Braga, J.C.; Martín, J.M. (2000). "Late Miocene Mediterranean desiccation: topography and significance of the 'Salinity Crisis' erosion surface on-land in southeast Spain: Reply". Sedimentary Geology. 133 (3–4): 175–184. Bibcode:2000SedG..133..175R. doi:10.1016/S0037-0738(00)00039-7. hdl:1874/1630.
  32. ^ Braga, J.C.; Martín, J.M.; Riding, R.; Aguirre, J.; Sánchez-almazo, I.M.; Dinarès-turell, J. (2006). "Testing models for the Messinian salinity crisis: The Messinian record in Almería, SE Spain". Sedimentary Geology. 188: 131–154. Bibcode:2006SedG..188..131B. doi:10.1016/j.sedgeo.2006.03.002.
  33. ^ Bache, F.; Olivet, J. L.; Gorini, C.; Rabineau, M.; Baztan, J.; Aslanian, D.; Suc, J. P. (2009). "The Messinian Erosional and Salinity Crises: View from the Provence Basin (Gulf of Lions, Western Mediterranean)" (PDF). Earth Planet. Sci. Lett. 286 (3–4): 139–157. Bibcode:2009E&PSL.286..139B. doi:10.1016/j.epsl.2009.06.021. S2CID 30843908.
  34. ^ Gargani J, Rigollet C (2007). "Mediterranean Sea level variations during the Messinian Salinity Crisis". Geophysical Research Letters. 34 (L10405): L10405. Bibcode:2007GeoRL..3410405G. doi:10.1029/2007GL029885. S2CID 128771539.
  35. ^ Weijermars, Ruud (May 1988). "Neogene tectonics in the Western Mediterranean may have caused the Messinian salinity crisis and an associated glacial event". Tectonophysics. 148 (3–4): 211–219. Bibcode:1988Tectp.148..211W. doi:10.1016/0040-1951(88)90129-1.
  36. ^ van Dijk J.P., Okkes F.W.M. (1991). "Neogene tectonostratigraphy and kinematics of Calabrian Basins. implications for the geodynamics of the Central Mediterranean". Tectonophysics. 196 (1–2): 23–60. Bibcode:1991Tectp.196...23V. doi:10.1016/0040-1951(91)90288-4. Retrieved 20 March 2023.
  37. ^ Lonergan, Lidia; White, Nicky (June 1997). "Origin of the Betic-Rif mountain belt". Tectonics. 16 (3): 504–522. Bibcode:1997Tecto..16..504L. doi:10.1029/96TC03937. hdl:10044/1/21686. S2CID 129585666. Retrieved 20 March 2023.
  38. ^ TURNER, S. (1 June 1999). "Magmatism Associated with Orogenic Collapse of the Betic-Alboran Domain, SE Spain". Journal of Petrology. 40 (6): 1011–1036. doi:10.1093/petrology/40.6.1011. Retrieved 20 March 2023.
  39. ^ Seber, Dogan; Barazangi, Muawia; Ibenbrahim, Aomar; Demnati, Ahmed (29 February 1996). "Geophysical evidence for lithospheric delamination beneath the Alboran Sea and Rif–Betic mountains". Nature. 379 (6568): 785–790. Bibcode:1996Natur.379..785S. doi:10.1038/379785a0. hdl:1813/5287. S2CID 4332684. Retrieved 20 March 2023.
  40. ^ Platt, J. P.; Vissers, R. L. M. (1 June 1989). "Extensional collapse of thickened continental lithosphere: A working hypothesis for the Alboran Sea and Gibraltar arc". Geology. 17 (6): 540–543. Bibcode:1989Geo....17..540P. doi:10.1130/0091-7613(1989)017<0540:ECOTCL>2.3.CO;2. Retrieved 20 March 2023.
  41. ^ Jackson, J. A.; Austrheim, H.; McKenzie, D.; Priestley, K. (1 July 2004). "Metastability, mechanical strength, and the support of mountain belts". Geology. 32 (7): 625. Bibcode:2004Geo....32..625J. doi:10.1130/G20397.1. Retrieved 20 March 2023.
  42. ^ Platt, J.P.; Soto, J.I.; Whitehouse, M.J.; Hurford, A.J.; Kelley, S.P. (1998). "Thermal evolution, rate of exhumation, and tectonic significance of metamorphic rocks from the floor of the Alboran extensional basin, western Mediterranean". Tectonics. 17 (5): 671–689. Bibcode:1998Tecto..17..671P. doi:10.1029/98TC02204. Archived from the original (abstract) on 2008-06-11. Retrieved 2008-04-04.
  43. ^ Jolivet, Laurent; Augier, Romain; Robin, Cécile; Suc, Jean-Pierre; Rouchy, Jean Marie (June 2006). "Lithospheric-scale geodynamic context of the Messinian salinity crisis". Sedimentary Geology. 188–189: 9–33. Bibcode:2006SedG..188....9J. doi:10.1016/j.sedgeo.2006.02.004. Retrieved 20 March 2023.
  44. ^ Duggen, Svend; Hoernle, Kaj; van den Bogaard, Paul; Rüpke, Lars; Phipps Morgan, Jason (10 April 2003). "Deep roots of the Messinian salinity crisis". Nature. 422 (6932): 602–606. Bibcode:2003Natur.422..602D. doi:10.1038/nature01553. PMID 12686997. S2CID 4410599. Retrieved 20 March 2023.
  45. ^ Aharon, Paul; Goldstein, Steven L.; Wheeler, Christopher W.; Jacobson, Gerry (1 September 1993). "Sea-level events in the South Pacific linked with the Messinian salinity crisis". Geology. 21 (9): 771–775. doi:10.1130/0091-7613(1993)021<0771:SLEITS>2.3.CO;2. Retrieved 20 March 2023.
  46. ^ أ ب Murphy L, Kirk-Davidoff D, Mahowald N, Otto-Bliesner B (2009). "A numerical study of the climate response to lowered Mediterranean Sea level during the Messinian Salinity Crisis". Palaeogeography, Palaeoclimatology, Palaeoecology. 279 (1–2): 41–59. Bibcode:2009PPP...279...41M. doi:10.1016/j.palaeo.2009.04.016.
  47. ^ A. Simmons (2000). "Faunal extinction in an island society: pygmy hippopotamus hunters of Cyprus". Geoarchaeology. 15 (4): 379–381. doi:10.1002/(SICI)1520-6548(200004)15:4<379::AID-GEA7>3.0.CO;2-E.
  48. ^ Petronio, C. (1995). "Note on the taxonomy of Pleistocene hippopotamuses" (PDF). Ibex. 3: 53–55. Archived from the original (PDF) on 2008-09-12. Retrieved 2008-08-23. {{cite journal}}: Unknown parameter |deadurl= ignored (|url-status= suggested) (help)
  49. ^ خطأ استشهاد: وسم <ref> غير صحيح؛ لا نص تم توفيره للمراجع المسماة autogenerated1
  50. ^ Warren, John K. (2006). Evaporites: sediments, resources and hydrocarbons. Birkhäuser. p. 147. ISBN 978-3-540-26011-0.
  51. ^ Majithia, Margaret; Nely, Georges, eds. (1994). Evaporite sequences in petroleum exploration: Geological methods. Editions TECHNIP. ISBN 978-2-7108-0624-0.
  52. ^ "Vast "Grand Canyon" Lurks 8,200 Feet BENEATH Cairo, Egypt". Biot Report 403. September 21, 2006.
  53. ^ Gargani J.; Rigollet C; Scarselli S. "Isostatic response and geomorphological evolution of the Nile valley during the Messinian salinity crisis". Bull. Soc. Geol. Fr. 181: 19–26. doi:10.2113/gssgfbull.181.1.19.
  54. ^ Gargani J. "Modelling of the erosion in the Rhone valley during the Messinian crisis (France)". Quaternary International. 121: 13–22. doi:10.1016/j.quaint.2004.01.020.
  55. ^ Pliny the Elder, Natural History, Book 3, Introduction.
  56. ^ أ ب Wells, H. G. (1920). The Outline of History. Garden City, New York: Garden City Publishing Co., Inc. ISBN 1-117-08043-9.
  57. ^ Mikolajewicz, U. "Modeling Mediterranean Ocean climate of the Last Glacial Maximum". Retrieved 5 March 2011.
  58. ^ Hanns Günther (Walter de Haas) (1931). In hundert Jahren. Kosmos.
  59. ^ "Atlantropa: A plan to dam the Mediterranean Sea." 16 March 2005. Archive. Xefer. Retrieved on 4 August 2007.

قراءات إضافية

وصلات خارجية

  1. The Messinian Salinity Crisis by Ian West (Internet Archive copy)
  2. A brief history of the Messinian on Sicily by Rob Butler. Archived
  3. Messinian online
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