Currently, the maple trees are producing massive quantities of seeds ( the Maple's are stressed). I'd love to germinate a few trees.
I already have a small batch of maple seeds collected, and I am waiting for them to dry out. I want to try the process of stratification.
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Last weekend, I read the book The Story of Earth: The First 4.5 Billion Years, from Stardust to Living Planet by Robert M. Hazen.
Reading books in not enough, I think spending a little time to try to process the information is helpful. Since this book is written in clear chapters, I'm just going to review what was in the chapters again.
1. Birth - The Formation of the Earth
The book starts out like any typical story of the big bang, and then from big bang, Hazen talks bout the formation of the stars. He talks about the formation of the sun and the elements. How gravity sucks hydrogen together to make a star, and how the compression of hydrogen leas to fusion.
This compression lends itself to a fusion inspired dance. Gravity compresses, fusion of hydrogen creates helium. Helium fuses to create carbon. carbon to make neon. neon to oxygen. Then magneium, silicion sulfur and etc.... The last stage of a huge star last only a day, it makes lead, then a star explodes
He talks about how our solar system started out as a gaseous nebula and how an exploding star nearby triggered the formation of our solar system. 4.6 billion years ago, the presolar gasses spun faster and faster, making a centralized core and a flattened pattern of gasses.
For clues of this time period, there are meteorites. The 4.566-billion chondrites
When the sun first formed, an intense radiant energy broiled the nebula, creating rocky droplets, called chondrules. (After the ancient greek word for grain)
A younger group of rock is called the anchondrites..They have been melted a reworked.
They represent a host of exotic meteorite types such as Howardites, eucrites, diogentites, ureilites, acapulcoites, lodranites ---most named for locality where they were found
Pallasite - snatch a core-mantle boundary --shiny metal mixed with cystals of olivine
2. The Big Thwack- The Formation of the Moon
About 4.5 billion years ago, a proto earth and a smaller planet were in competition for the same space in the solar system. The smaller planet is called Theia (Theia the titan goddess who gave birth to the moon) Theia was a 1/3 of the earth mass. Both of the planets collided and formed the earth and moon. At the Roche limit, the moon formed 15 miles up. Moon lacks volatiles because they were blasted away and it lacks an iron core becuase that core ended up with earth.
Currently, the moon is 239,000 miles away. It inches away 3.82 centimerers every year. In early eath, the moon was huge and volcanic. It would have been bright and would have blcoked out the stars in the sky. Total angular moment of the system hasn't changed that much. 4.5 million years ago, everything was spinning fast. It still took 8,766 hours to go around the sun, but days were only 5 hours long. the moon only took 84 hours to go around the earth. Monster volcanic tides were found on earth.
3. The Black Earth - The formation of the Basalt Crust
The earth cooled via conduction, Convection and radiation.
Olivine crystals started to form. Sinking into the magma depths.
Magmas became depleted in magneisium and were more concentrated with calcium and alumnimum.
On moon, a second cystal formed along olivinr, anorthite.
On earth, with greater pressures pyroxene appeared.
They formed in a hard rock called peridotite
Early peridotite crust sank.
Basalt comes about. Two varieties are plagioclase and pyroxene.
As masses of peridotite formed and sank, they were reheated and half-melted. The repeated half melting of peridotite changed to the composition of the rock.
Basalt does nt have many crystals. Diabase and gabbro. Earth had a basalt crust that floated above magma.
4. Blue Earth - The Formation of the Oceans
For some reason, earth volatiles did not evaporate. This is not the case with other planets. It lost some water when it collided with Theia, but on a whole earth has kept a large percentage of its water. Earth probably has a vast resevior deep underground. Maybe it stayed because of earth's magnetic field (???)
In Western Australia, in the Jack Hills, Some of the oldest rocks are found. Zirconium seeks its own kind and forms tiny crystals. Zirconium crystals are impressively stable, they can get heated and recycled in rock and not lose their structure. Some of them are known to be 3 billion years old. Zirconium crystals can tell time because they can incorporated uranium, and uranium's decay is a useful clock. Two of every 3 atoms are oxygen, which gives clues about temperature formation ( Recall technique of Oxy-16 and Oxy-18) and temperature can be an indicator of water content. Because of findings from theste crystals, some scientists argue that 4.4 billion years ago, the earth was already cooling down.
The early earth ocean was hot and salty. Most salt today is landlocked in salt domes and evaporate deposits. There were no continents for the salt to get tied up into, and thus the early oceans might have been twice as salty as it is today. The early oceans were also very acidic. The hadean air had lots of co2 and co2 combines with water to form carbonic acid. ..hydrogen ions, hydronium ions plus bicarbonate. This acidic ocean weathered rocks faster. --At that time the sun was faint
5. Gray Earth - The Formation of Granite Crust
The unique melting of silicom rich basalt lead to the formation of Granite. Granite has four basic components. Crystals of quarts (silicon oxide), two kinds of feldspar -rich in potassium and sodium-- mica/ pyroxene/ amphibole...sometimes zircon.
After this, we have to appreciate Buoyancy. Granite floats on Basalt. It accumulates mountains on top of basalt. Plate tectonics; Granite floats and basalt sinks. This is the key to the origin of the continents. Basalt get recycled and reheated. Granite floats and forms continents.
Question: Has granite stopped forming? If it has, what stops it? If not, are we going to become one giant granite ball?
6. Living Earth - The Origins of Life
amino acids made by Harold Urey
Carbon experiements
There are quasi-living sytem of molecules
Citric acide cycle -It starts with acetic acid, reacts with Co2 to form pyruvic acid, then reacts with more co2 to make oxaloacetic acid..eventually the molecules get so big, that they break up into acetic acid again.
Self-replicating auto-catalytic network- they are complicated reactions that speed up the development of themselves but then go on to destroy their neighbors.
RNA molecule that made copies of itself. Some how these RNA polymers adapted to out compete their RNA Neighbors. Perhaps they bonded onto minerals.
Also think about the lipid communities.
Early microbes learned to take normal reactions, that had energy. They they developed some type of enzyme to accelerate the process. Early microbes reduced iron to form red mineral hematite. The geo-sphere and the biosphere co-evolved.
Then photosynthesis comes about. Hopanes survive after a photosynthetic cell dies out.
7. Red Earth - Photosynthesis and the Great Oxidation Event
Microbes have figures out quite a few ways how to harvest light and energy sources. A few photosynthetic pathways produce no light at all. Biochemist Robert Blackenship and arizona state university study these microbes. Microbes shuffle and swap light producing genes. Plants get their photosynthesis from two more primitive pathways - Photo system 1 and Photo system 2.
Earth is always evaporating hydrogen. The heavier o3 just lumbers around with the pull of gravity.
NOX microbes and peroxide microbes.
The questionable field of Microbe fossils. They have been found in Black chert, black shale and stromatolites. Nora Noffke added a forth one Sandstone- she found evidence of microbial mats.
Along with life-forms came the mineralogical explosion. It may be that microbes add to the formation of minerals. An oxygen rich subsurface lead to the formation of minerals. Molybdenite -mineral of molybdenum. Oxygen from microbes transformed Riheium and Molydbdenum.
Life is linked with 45 hundred known chemical species. Some of the new minerals provided habitats for life. Life has continuously co-evolved with rocks and minerals.
8. The 'boring' Billion - The mineral Revolution
The boring billion may refer to our ignorance of this time period. The cratons have a complex history. The boring billion saw he formation of two super continents. Rodina and Pangea .....there was also an intermediate ocean. The climate was surprisingly stable.
During this time, there was a mineral explosion. Magazine American Mineralogist.
This time period was very smelly- a sulfide laden ocean.
9. White Earth - The Snowball-Hothouse Cycle
From a time period of 2.5 billion to 542 million years ago, the climate of the earth altered radically. There are mechanisms that keep the earth's climate in check, and there also mechanisms that send extreme positive or negative feedback loops.
The earth glaciated at least 3 times. Sturtian glaciation peaked 750 million years ago. The Marinoan glaciation follow 650 million years. Gaskiers glaciation occurred at 580 million years ago.
Tillites are one type of evidence for glaciation.
An interesting fact is that there is frozen methane in the bottom of the ocean.
During the end of these cycles, there is growing evidence that microbial communities started colonizing land. According to the article ' The Inception of the Clay Minerol Factory' by Martin Kennedy of the University of California, Riverside, indicated that the rise of oxygen to the degree we know now was due to feeedback between microbes and clay minerals. Clay led to the burial of carbon and the rise of oxygen.
Also there is ancient phosphorus strata- in some communities phosphorus was the missing element,
With this rise of oxygen, it led to the rise of animals. Margulis believes in endosymbiosis. She believes that traits are shared among different animals as a survival technique. Donald Williamson proposed that butterflies represent the merging of two very different organisms- the worm-like caterpillar and the winged butterfly. --This sharing of traits furthers evolution.
10. Green Earth. The rise of a Terrestrial Biosphere
You can break up green earth into three acts.
Act 1- The beginning of the Cambrian period, 542 million years ago. Rodinia was broken into many small pieces.
Act 2- 300 million years ago, Gondwana collided with Laurentia to produce Pangaea and the Appalachian mountains.
Act 3- The Opening up of the Atlantic Ocean 175 million years ago, when Pangaea fragmented.
530 million years ago, many types of animals learned to build their shells out of hard minerals- usually using calcium carbonate or silica.
Lifeforms began colonizing the land. 400 million years ago, lifeforms were strange. Prototaxites specimens--fossils--their biological markers--fossilized tube like structures-turned out to be fungal. Meaning that their was fungus the size of a tree.
The invention of leaves, took million of years more. 360 million years ago, forests emerged and the land became emerald green. Plants and fugal filaments co-evolved.
Then the first fist started walking on land 395 million years ago and turned into amphibians.
300 million years ago, earth forests did well and another oxidation event happened. This benefited animals, and some organisms grew larger. Giant insects happened. There were monster dragonflies with 2 foot wingspans.
Then there are times of mass death.
251 million years ago was the great dying. 96% of all marine species died and 70 percent of land species. --not sure what caused it--maybe several factors such as decreased oxygen, large scale volcanoes, collapse of ozone layer.
Then the age of Dinosaurs, the mesozoic era! It saw the development of flowering plants. Then 65 million years ago, a giant asteroid that was 6 miles wide, caused another great dying event.
The rise of humans started with that asteroid 65 million years ago. Little mammals became big. 2.5 million years ago, homo habilis came around.
11. The Future - Scenarios of a Changing Planet.
I'm going to keep my notes on this chapter short. The future for earth is certain. It will get swallowed or baked by the sun. A very very very very long time from now, life will not exist on earth. Our short term future, that is in our hands.
General Notes:
To study petrochemistry, it is important to understand what are the common elements an earth. Oxygen, Silicon, Iron, Calcium (donar 2 e), Magnesium (donor 2 e) and aluminium (donor 3e)..then sodium and potassium.
Oxygen is an electron acceptor, (of two e)
Silicon is a electron donor. (4 e)
Quartz- Sio2
Iron is versatile. (sometimes donor of 2e, produces greenish color, will donote 3e- red rust formed)
Iron is a donar of par excellence) --also metal
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