NOTE, this is an Earth cache and the questions at the end must be answered and sent to the Cache Owner, once sent, you may log as found and the CO will contact you if there are any problems.
Ballina coast is a diverse area containing the length of Angels Beach (1.5km), rock shelfs at Flat Rock and Black Head, Black Head headland, a large area of diversely vegetated regenerating bushland and a tall sand hill (‘The Knoll’) with panoramic views in all directions.
There are four main landscape types along the Ballina Coastline - beaches, headlands, alluvial & estuarine deposits, and the sand sheets or sandplains. Nearby Broken Head forms the oldest rocks of the area. These are Palaeozoic age rocks of the Neranleigh-Fernvale group. The Tertiary age Lamington volcanics, consisting predominantly of basalt, overlay these metasediments.
The headlands between Lennox Head and Ballina are basalt outcrops resulting from lava flows from the Mount Warning Shield Volcano. These volcanos mostly produce basalt lavas, although they can produced some other types of lava as well (e.g., rhyolite). The rocks at Flat Rock are basalt, which supports the idea that they're from the volcano. The Tweed Volcano erupted between 23 and 24 million years ago, and is now heavily eroded. The sand that separates Flat Rock from the mainland is superficial, covering the rocks below. The exposed rocks have been eroded by waves and cut into a platform; this style of erosion is common in coastal areas.
The Richmond Catchment is one of the wettest areas in NSW, and has some of the most intense and erosive rainfall in NSW. Average rainfall fluctuates between 1600 and 1700 millimetres per year, with the highest falls in summer (November to April). The prevailing wind is from the southeast, however there are strong northerly winds throughout the summer months.
This area is an integral part of to the local ecosystem valued for its diverse coastal native vegetation and habitat value. Significant landscape features include a complex matrix of native vegetation, the open beach and dune / swale complex, the prominent rock platform at Flat Rock and a prominent sandy knoll located in the north-west corner offering panoramic views. The area has important Aboriginal cultural and heritage values. Sand mining and clearing has caused disturbance to large parts of the area.
The beach, incipient fore dune and rock platform of Flat Rock provide resting and roosting habitat for sea turtles and resident and migratory seabirds. The rocky shoreline is an important marine intertidal zone providing habitat for marine invertebrates and fish.
Info – Ballina City Council, Reserve Plan of Management. Supplementary information courtesy of Queensland Museum.
Q1. The headlands and rocky outcrops resulted from what event? What age did this happen?
Q2. Describe what you see, looking out at Flat rock from the beach.
Q3. In your own words, describe how you think flat rock was created.