Geological Information on St. Patrick’s Print E-mail
According to the Plans and Policy for a System of National Parks and Protected Areas, the geological history of Grenada began approximately 38 million years ago in the upper Eocene Period. At that time however, there was only a shallow sea where Grenada now exists. The sediments deposited were composed of sand, silt and mud, and calcareous mud; the rock formed from this process is now known as the Tufton Hall Formation. In between the sediments of the Tufton Hall, geologist found layers containing volcanic minerals and other deposits of volcanic origin. Volcanic activity became more frequent in the Oligocene period (37-26 million years ago.) The volcanic activity during and following the deposition of the Tufton Hall formation, deformed and uplifted the rock, resulting in the folding and faulting which can be seen just north of Levera Beach.

It is also reported, that the oldest of the volcanic rock series are the andesite domes of northern Grenada, which formed in the Miocene Period (26-5 million years ago). These andesite domes (Mt. Alexander, Mt. Rodney, Mt. William) have been estimated by radiometric dating to be 21 million years old. The middle Miocene Period is not well represented in Grenada, but the andesite domes of Levera Hill and Levera (Sugar Loaf) Island represent volcanic activity near the end of the Miocene time. Thought to be concurrent with the Levera events were the eruption of the southeast mountain and Mt. Lebanon centers, which recorded the first major shift of eruptive centers to the south.

Levera Lake or Pond is believed to have been through a series of interesting changes over the last few thousand years. It is estimated that approximately 2500 years ago, this area was part of the sea in the form of a lagoon. Over the ensuing years that followed, it was gradually enclosed by the mangroves, as they trapped the silt, thus forming a headland. However, what is quite interesting is the revelation by historical maps, of an island in the middle of the Lake. Over the years it too has been linked to the land formation . Hence, one is left to wonder, whether this formation has been part of* the volcanic activities which occurred during the later years.

The final stage of volcanic activity involved the formation of explosion craters throughout the Island, most notably at the Lake Antoine, St. George's Harbour, the Punch -Bowl at Mt. Rich and Grand Etang locations. Over the past years however, it is believed that the volcanic activities on the Island have been dying down as experienced by the dropping temperatures of the thermal springs at Tufton Hall from almost 50 degrees C. - around 35 degrees and at Peggy's Whim; from about 44 degrees - 38 degrees C.