- UID
- 211370
- 热情
- 295
- 人气
- 322
- 主题
- 16
- 帖子
- 822
- 精华
- 0
- 积分
- 736
- 分享
- 0
- 记录
- 0
- 相册
- 4
- 好友
- 0
- 日志
- 0
- 在线时间
- 800 小时
- 注册时间
- 2009-12-27
- 阅读权限
- 20
- 最后登录
- 2023-8-14
升级    47.2% - UID
- 211370
- 热情
- 295
- 人气
- 322
- 主题
- 16
- 帖子
- 822
- 精华
- 0
- 积分
- 736
- 阅读权限
- 20
- 注册时间
- 2009-12-27
|
Do earthquakes create fault lines?
It is now known that the powerful earthquake that smashed buildings, cracked roads and twisted rail lines in Christchurch also ripped a new 3.5m-wide fault line in the Earth’s surface. Canterbury University geology professor Mark Quigley said “a new fault” had ripped across the globe and pushed surface areas up. He said the quake was caused by the collision of the Pacific and Australian tectonic plates. “One side of the Earth has lurched to the right - up to 11 feet (3.5m) and in some places been thrust up,” Mr Quigley said. New Zealand sits above an area of the Earth’s crust where two tectonic plates collide. The country records more than 14,000 earthquakes a year, but only about 150 are powerful enough to be felt above land, about 3 'felt' jolts per week on average. New Zealand’s last major earthquake registered 7.8 on the Richter scale and hit the South Island’s Fiordland region on July 16, 2009 (just before new moon+closest perigee), moving the southern tip of the country 30cm closer to Australia.
The devastating earthquake that rocked Haiti in January was also supposedly unleashed by a previously undetected fault line - not the well-known one scientists initially blamed, according to an analysis of new data. Eric Calais, a professor of geophysics at Purdue University in West Lafayette, Ind. said the analysis shows that most, if not all, of the geologic movement that caused January's magnitude-7.0 earthquake occurred along this newly uncovered fault, not the well-documented Enriquillo fault. Stein noted that even in California, whose many faults have been closely studied, about half of all moderate or stronger quakes occur on previously unknown faults.
Sometimes it seems that some scientists cannot see what is within an inch from their noses. Perhaps these "newly discovered" faults were unknown because they weren't actually there before the earthquakes occurred! The islands of New Zealand sit across what are now called the Australian and Pacific Plates, which for most of their shared boundary interact. To the south, the Australian Plate slides beneath the Pacific Plate, while further north the opposite applies. This plate boundary is part of what is known as the 'Ring of Fire'. Between these sections for some 400km between Milford Sound and Hokitika, the edges of the two massive sections of the Earth’s crustal plates "collide" head on. But do they collide or were they once one piece that got broken into two by an event? If you drop a china plate and it breaks into two pieces, can you say that previous to the drop the two halves HAD secretly collided, but that we had no way of knowing that the potential for separation was actually there, and it took the drop to separate them again and to show us - what? Well, when it comes to earthquakes seismologists are saying to show us where the "fault" was all the time.
This argument is full of holes in logic. To say eruptions have nowhere to go except upwards, therefore the Southern Alps result, is to say you have a mysterious crack in the ocean floor, formed somehow in the distant past, that is waiting patiently for an event to unfold with enough energy and heat to build itself up into a mountain range. It is such a weak case that geologists introduce a bit of biffo. They say that in the process the tectonic plates grind, rotate and square off against each other, the immense forces building until every 250 to 300 years or so a sudden movement releases the pent-up pressures. This, they say is the Alpine Fault, which last moved significantly in 1717. So we do not have the notion of underground magna bubbling through from the molten mantle at all. According to these geologists it is the heat generated from rocks in the land crust on top of the molten mantle, rubbing together that causes the molten lava. So what of the actual molten core that lies beneath the earth. Is that another system? And how and when does that stuff get out? And why do some earthquakes occur at a depth of 300kms, when the land crust is less than 50kms deep?
I question that any fault line was ever there first, before any molten matter decided to bubble through it. It is more likely that the molten mantle bubbles through wherever it wants to, and this creates a weak section in the crust, through which later eruptions may follow if stresses occur in the immediate vicinity. There is no way the Alps caused the Alpine Fault line which then goes on to cause more earthquakes within 500kms of it. That is like saying footprints create feet and Walking Clubs, or wrinkles cause worry and family tragedies. Maybe in a world in reverse, but not this one. Otherwise a sunburnt arm would cause the sun to increase in heat. It does not mean earthquakes may not still occur around the same area of known fault lines. But forever frequenting the same dairy that sold you a winning lottery ticket won't guarantee you another win. You just got lucky once. Seeing a fault line host a new earthquake does not mean the fault line caused it. It may mean the earthquake is opening up a new old wound because of internal machinations deep in the molten core directly under that old wound. That is a long long way from being causal!
Let us ponder this. The 4 September earthquake happened 12kms underground. Current geology wants us to believe that a mighty loose cannon of a 650 kiloton ball of energy, from 12kms away, hurtling surfacewards, has some sort of steering mechanism that seeks out old fault lines to surface through. Imagine an H-bomb the size of that which destroyed Hiroshima, heading towards Christchurch from 12kms away. Now imagine 43 such bombs in one explosive package of energy and you have the size of the 4 September earthquake. Would the bomb that struck Hiroshima have had time to seek out the best skyward path to the city, or did it just drop anyway? After falling from the plane, did it wander around in the sky until it found a sky-hole corridor through the air down to the city that some previous (unknown) bomb had created? Would a 650 kiloton monster earthquake have bothered to set itself within the confines of a previously carved faultline? It is a little hard to imagine why it should be so respectful. It is not as if fault lines are territorial in the way the Mafia carved up Chicago for neighborhood racketeering. Earthquakes can and do go where they choose. If there is a fault line there already, then a shake may shake that too and an observer will say the fault line was active. If there is no fault line the earthquake will make one.
And scientists now do agree that the 7.1mag earthquake created a new fault line that either they didn't know was there or that actually wasn't there. This surely throws the old theories out the window. If a road planner is told of old roads that are not on modern maps then he does not know his district very well, especially if travellers inform him they have been using these old byways for years. It cannot both be that earthquakes get caused by old fault lines and at the same time earthquakes may choose to ignore them preferring to create new cracks in the countryside in totally different places to those previously used.
The reason some geologists will not change their views is political. Having carefully built their careers around the well-known scenario they must hold onto the plates-rubbing-together idea, or look for another cause for the emergence of heat. For plates to rub together means the plates would have to be already separated (you have to have two parts to rub together). What they don't want to face is the notion that there may be a tide within the earth that brings earthquakes, eruptions and volcanos at particular times, and that these times may coincide with what other known tides are doing. The answers are not looking down at the drums, the horses there have all bolted. The answers are upwards, at colossal movements in the heavens that cause tides deep within the earth. Why else would the Te Anau earthquake have been on new moon/closest perigee, the Christchurch 7.1mag.on new moon+second closest perigee, the Napier earthquake on full moon/fourth closest perigee etc etc?
My suggestion to all the geologists, seismologists and other earthquake specialists is to forget fault lines, they will lead to nothing useful. It is like examining tyre marks to see when the next vehicle will drive past. It is money totally wasted. In NZ we have recurring earthquakes and we are in a position to lead the world in predicting them. There is loss of property and a huge denting of the country's economy. A loss-control programme would save us millions. Ignoring faults and rebuilding Christchurch in ways that minimised earthquake damage would be a start. The old city would gradually be replaced. Systems that monitored lunar gravitation would be more useful than just installing new drums, taking core samples from the Alps. The earthquake risk period at the moment remains 18-25 February for a bigger shake. Another will probably happen in a month's time, as the moon edges closer to us this year. |
|
发表于 2011-2-23 17:14:18
分享
收藏
