Friday 27-05-22

2022DepotBeach
Friday 27 May, 2022 We visit the Mogo Zoo, about 10 kms south of Batemans Bay. Friday 27 May, 2022 We are interested in seeing if the 2020 fires had damaged the zoo or its animals. Friday 27 May, 2022 I am very lucky to get the fence into such sharp focus. Friday 27 May, 2022 A local tells us that during the fires the animals were shipped out to farms and other places to protect them.
Friday 27 May, 2022 Imagine transporting animals like giraffes to local farms. It seems that the fires brought out the best in people (excluding Prime Minister Morrison of course). Friday 27 May, 2022 The big cats would have been difficult to transport and feed. This visit showed us that there were nowhere near as many lions at the re-opened zoo as there were on our first visit Friday 27 May, 2022 Where did the gorillas go I wonder? Friday 27 May, 2022 All of the burnt trees seem to have recovered and it is difficult to see any damage right now.
Friday 27 May, 2022 A gibbon swings through the trees. Friday 27 May, 2022 Looks like no one uses an SLR camera any more. Friday 27 May, 2022 One thing we notice during this visit is that there aren't any tigers any more. I wonder where they are? Friday 27 May, 2022
Friday 27 May, 2022 There appears to be an electric fence in the background. Even if it isn't electric, I wonder why the Gibbons don't cross the moat and escape. Friday 27 May, 2022 These are ring-tailed lemurs kept in beautiful surroundings. No fire damage is evident here. Friday 27 May, 2022 This gorilla and the gorilla family next door are back in their enclosures. Friday 27 May, 2022 We now drive to Guerilla Bay, 13kms south of Batemans Bay.
Friday 27 May - 2022 Guerilla Bay From the pamphlet: Guerilla Bay is a hidden, sheltered and picturesque bay formed in some of the oldest rocks (dating back 510 million years) along Eurobodalla's coastline. These rock formations are layers of chert and slate and initially laid down in the ancient Pacific Ocean, before becoming part of the Gondwana continent, possibly during an interval of subduction. Friday 27 May, 2022 - Guerilla Bay From the pamphlet: A subduction zone is an area where tectonic plates converge with one plate overlapping and overriding the other; they can sink to great depths in the Earth's mantle at a 25° to 90° angle. Through the high temperatures and pressures associated with this process, seabed sediment converts to rock. Friday 27 May, 2022 - Guerilla Bay From the pamphlet: Although plate movement only occurs at a rate of centimetres per year, an active zone such as in Japan or New Zealand can cause tsunamis and earthquakes. Through plate movement, sediments and rocks can travel long distances to become part of landmasses. Friday 27 May, 2022 - Guerilla Bay From the pamphlet: Squeezed, bent and broken after they formed, these Guerilla Bay rocks consist of a mix of fragments called tectonic melange. Contained in these chert rocks are tooth-like microfossils (less than mm) from the gut of extinct eel-like animals but a microscope is required to see these minute fossils. Note about chert: "Chert is a hard, fine-grained sedimentary rock composed mostly of crystalline quartz. Chert is characteristically of biological origin, but may also occur inorganically chemically (stone axehead) or a diagenetic replacement (petrified wood)".   Over this weekend, I don't immediately recognise anything that is obviously chert.
Friday 27 May, 2022 - Guerilla Bay This rock in the cliff face is very beautiful. Is there chert in here? Dunno. Friday 27 May, 2022 - Guerilla Bay Jenni said that I can buy her this house. What a beautiful house and in such a beautiful setting. Would that I could make her dream come true. Friday 27 May, 2022 - Guerilla Bay Layers of material are visible in this exposed sedimentary rock. Is there some chert here? Dunno Friday 27 May, 2022 - Guerilla Bay There is a small beach just in front of us called Guerilla Small Beach. Walking over this uneven and lumpy rock is very difficult and painful (my left ankle is still bad).
Friday 27 May, 2022 - Guerilla Bay Up the coast a bit we can see Jimmies Island. This island is World Famous for absolutely nothing. Because this is a Marine Park, no one is allowed onto this island and the same marine park regulation prevails for the other 52 islands in the park. Friday 27 May, 2022 - Guerilla Bay The amazing thing about these rocks being from Cambrian period, is that animal life on earth was developing rapidly; it was called the "Cambrian Explosion". "The Cambrian lasted 53.4 million years from 538.8 million years ago to 485.4 mya. By the end of the Cambrian, nearly all the major groups of animals we know today (the phyla) had evolved."   Dinosaurs first appeared about 230 Mya - quite recently really. Friday 27 May, 2022 - Guerilla Bay Even more amazing is that, ~500 Mya, the Australian continent was part of a super-continent called Gondwana. When these rocks at Guerilla Bay were created, our continent was around about the equator. The rocks were first laid down in layers as sediments in an ancient ocean that surrounded Australia. By the time Australia broke away from Antarctica, ~80 Mya, we were down near the South Pole. Friday 27 May, 2022 - Guerilla Bay Jenni and I walk to the southern end of Guerilla Bay. The rocks here are the same as those on the northern side.
Friday 27 May, 2022 - Guerilla Bay Another small grove of littoral forest grows down to the beach. Our car is parked over near the houses in the middle of the beach. We're concerned about getting bogged because of recent heavy rains but we get the car out OK. Friday 27 May, 2022 - Guerilla Bay Guerilla Bay is right in the middle of a pink zone which means that everything is protected. You can't even pick up dead sea shells here. Friday 27 May, 2022 - Guerilla Bay We then walk to the Northern side which is even more beautiful. Friday 27 May, 2022 - Guerilla Bay Imagine the amount of force required to tip that rock on the other side of the water, and the rocks in front of us, to almost vertical. The actual tilting would have happened ~500-400 Mya when the ocean sands and mud subducted into the earth's surface and were converted to rock.
Friday 27 May, 2022 - Guerilla Bay You're allowed to take pictures of this seaweed but you can't remove it. Friday 27 May, 2022 - Guerilla Bay "The rocks at Guerilla Bay consist mainly of feldspathic greywacke, chert and shale of the Wagonga Group that has been squeezed, bent and broken after formation, possibly as a result of compressive movement within the ancient subduction zone." Friday 27 May, 2022 - Guerilla Bay "Greywacke is a variety of sandstone characterized by its poorly sorted angular grains of quartz, feldspar, and other small rock fragments. Greywacke is a texturally immature sedimentary rock generally found in Paleozoic strata." Of interest: quartz and feldspar are earth's most plentiful minerals. Paleozoic means Ancient Life when life flourished in the seas. It is the longest of the Phanerozoic eras, lasting from 538.8 to 251.902 million years ago, and is subdivided into six geologic periods (from oldest to youngest): Cambrian, Ordovician, Silurian, Devonian, Carboniferous, Permian. 0 Friday 27 May, 2022 - Guerilla Bay the Wagonga Group is the name geologists have given to a unique rock formation just North and South of both Batemans Bay and Narooma.
Friday 27 May, 2022 - Guerilla Bay This small section of rock is called a fold. Friday 27 May, 2022 - Guerilla Bay The folding is caused by the material being squeezed on both sides. Anticlines look like the letter A and synclines look like the letter V. Friday 27 May, 2022 - Guerilla Bay So, how did this stuff get here? Geologists tell us that this Wagonga Group was brought to the surface during seafloor spreading (that created the Tasman Sea) 80 to 60 million years ago. Australia had separated from Antarctica by then. Friday 27 May, 2022 - Guerilla Bay This kind of metamorphic rock has a distinctive beauty about it.
Friday 27 May, 2022 - Guerilla Bay In this picture you can see the layers of the original rock types that were cooked and pressured deep underground. So another question is: how many more years before that did it take to wear away the original rocks on the earth's crust into fine particles that could gather into slate and mudstone? Another billion? Who knows? Friday 27 May, 2022 - Guerilla Bay This is quartzite which is is quartz sandstone cooked for a few million years in the earth's mantle, i.e. it is a metamorphic rock. Quartzite is a hard, non-foliated metamorphic rock that was originally pure quartz sandstone (SiO4). Sandstone is converted into quartzite through heating and pressure usually related to tectonic compression within orogenic belts. Quartzite contains 89-98% quartz with iron hydroxides (2-3%), silicon and chalcedony (4-5%). The stone also contains impurities of mica, talc, feldspar, and other minerals. Friday 27 May, 2022 - Guerilla Bay What a glorious place for a house overlooking Guerilla Bay. Glorious except during bush fires. Friday 27 May, 2022 - Guerilla Bay We drive a little farther along the small road to Burrewarra Point and park the car. It is a short walk to the lookout.
Friday 27 May, 2022 - Guerilla Bay Fan fungus grows on a tree near the lookout. Friday 27 May, 2022 We came to this lookout last year, when we looked for Guerilla Bay but did not find it. Instead, we finished up here, a bit south of Guerilla Bay. We're looking up the coast to Jimmies Island near Rosedale Beach. Last year we saw sea lions frolicking in the small bays below us but no such luck this year. Friday 27 May, 2022 We're back at base camp where a trio of kangaroos graze in front of our cabin. Friday 27 May, 2022 I had to look up what the collective noun for kangaroos is: "mob, troop or court". Tonight for dinner, we buy a chicken and some salad and eat at the cabin.