中四地理~關於plate tectonics!!!!!!!!!

Q1. 可能會... 但要視乎地球magma既流動方向會唔會改變...
因為pangaea係受到地球底層既magma改變流動而break into pieces.
Q2. 你呢題可以分開兩問...
我分開答你好了...
2.1
佢地兩個boundaries同樣係受到convection of magma影響的~
divergent currents => constructive plate boundaries
convergent currents => destructive plate boundaries
constructive plate boundaries係指兩塊plates越分越開(plates diverge from each other)
see also :
http://en.wikipedia.org/wiki/Divergent_boundary
destructive plate boundaries係指兩塊plates撞埋一齊(two plates collide)

see also :
http://en.wikipedia.org/wiki/Destructive_plate_boundary

2.2
正如我上面講左,
magma係有convection currents,
但唔同既boundaries,
係靠plates移動方向界定的~
2.3
covection currents係唔會有slide apart的,
只有convergent或者divergent...
between Nazca plate同Pacific plate,
係divergent currents.
***
唔識可以再問,
希望我仲可以答到你~

2008-11-11 16:19:57 補充：
Q1. 有少少補充...
上面我答既呢一句有少少問題...
「因為pangaea係受到地球底層既magma改變流動而break into pieces.」
其實應該為
「Starting about 200 million years ago, the Pangaea began to break up due to differential gravitational forces.」

2008-11-11 16:23:49 補充：
2.3 補充
你一定要分清楚,
magma同plates係唔同的~
magma係熔岩
plates係版塊

magma會有convection current,
但convection currents係唔會有slide apart的,
只有convergent或者divergent...

between Nazca plate同Pacific plate,
係divergent convection currents.
佢地兩塊plates係diverge, 唔係slide apart

1. 會, 只要force 夠大。唔知邊度話其實d continents係每唔知幾多年就 移近幾cm, 其實magma currents都係不斷推動plate的話, 遲早有日會再
break down, 但係可能會用幾百萬年既時間lor

2.constructive plate boundaries即係下面推動d plate movement既係
diverging既magma currents, 因為係divergent, 兩塊plates會分開, 中間既空位會有magma湧出黎, create左一d new land, 有建設性, so叫constructive
plate boundaries

destructive plate boundaries即係下面推動d plate movement既係
converging既magma currents, 兩塊plates會撞埋一齊(collide), denser plate就插左落去less dense下面令有d land消失左, so叫destructive plate
boundaries

如果係constructive, 會分開而唔係slide apart, slide sideways的係叫
conservative plate boundaries, 因沒有create land/令land disappear, 只令
plates擦身而過, so叫conservative plate boundaries