Wied il-Għasri (Għasri Valley in
Maltese) is a sea canyon (or gorge) on the Maltese island of Gozo. The
gorge continues on the land towards the village of Għasri. The valley
is known for its quiet beach, which is 300 metres inland from the sea.
The sea is only accessible via a narrow cove with high cliffs on both
sides, carved into the rocks. It is very popular
with divers who like to explore the surrounding underwater caves. The
very narrow and secluded bay is also a heaven for those who seek a quiet
bathing area. The area is great for a swim on a fine day but is
especially spectacular on windy days when you can enjoy the rage of the
sea splashing against the cliffs from a safe distance. Although it
seems inaccessible, a series of steps have been cut into one side of
the cliff face, taking you to the tiny beach.
Most gorges were formed by a process of long-time erosion from a
plateau or table-land level. The cliffs form because harder rock strata
that are resistant to erosion and weathering remain exposed on the
valley walls.
The rocks exposed in the island comprise a marine sedimentary
succession, mostly composed of limestones and marls and deposited in a
period between Upper Oligocene and Miocene. There are five geological
formations constituting the Maltese archipelago. From the oldest to the
youngest the formations are:
- The Lower Coralline Limestone Formation, consists of pale grey, hard,
shallow marine biomicrites and biosparites, and outcrops in a
restricted coastal stretch forming subvertical cliffs.
- The Globigerina Limestone Formation appears as a yellowish,
fine-grained, planktonic foraminiferal limestone and dominates in
southern Malta and western Gozo.
- The Blue Clay Formation that consists of grey, soft marls, clays and
silty sands, extensively outcrops along gentle slopes.
- The Greensand Formation is composed of bioclastic carbonate rock
which is abundant in glauconite, and was deposited in a warm marine
environment.
- The Upper Coralline Limestone Formation, forms plateaus and is
frequently weathered into steep cliffs and well-developed karst
topography.
If you observe this map of Gozo, you can see the zone where Wied
il-Għasri is located is painted as pink colour (Lower Coralline
Limestone).
But, how
this gorge was formed? Deep meandering gorges cut into the Lower
Coralline Limestone: In
contrast to the overlying Globigerina Limestone where weathering and
mass movements generate broad valleys and gentle reliefwatercourses,
the Lower Coralline Limestone drainage has produced deep entrenched
meanders and gorges. The Lower Coralline Limestone is chemically pure
and the predominant geomorphological process is solution which acts
predominantly along water courses.
For the tasks of this Earthcache you must to go at the coordinates. The
signal GPS isn't very good, please see the photo WAYPOINT for
known where is ubicated the place (last curve before the final stairs).
After the observations and the tasks at this
site, you can go to the beach for the final question and, if you want,
you can take a bath!