註:廖明山先生現為弘元石材股份有限公司董事長,對教育有份執著與熱誠。
文/大二生:蔡乙謙、包荷雅、李千謙、陳芷琳、許淑樺
這學期的岩石學課程有機會到田寮月世界進行野外實習。位於高雄的月世界是惡地地質公園,主要由泥岩、頁岩和砂岩等組成,表面佈滿許多溝蝕,部分地方甚至出現刀刃狀的山峰(如圖一),成因與頁岩、泥岩膠結疏鬆的特性有關。園區最大的特色包括泥火山、泥漿惡地和奇岩怪峰。泥火山和一般火山不同,形成原因是岩層中的氣體和水分以及地下流體的壓力釋放,沿著岩體裂縫噴出地表。泥岩惡地的成因則為,分佈在台灣南部上新世到更新世的古亭坑層泥岩,受地殼抬升作用與河川向下侵蝕作用而形成了丘陵地。奇岩怪峰的生成跟岩層的組成有關,岩層中有砂岩和礫岩,因此相對堅硬,在差異侵蝕下造成凸起。
惡地地形因地表極易受水流侵蝕,所以形成密密麻麻的侵蝕溝,加上土壤疏鬆,使得植被難以附著,造成了惡地大部分土壤表面都光禿禿的。至於為何惡地上依然看得見少量植被,除了某些植物適應力特別強,也有可能因為原先已有植被及適合植物生長的土壤,經過數萬年的土地抬升,便形成了這副景象。少數能見的植物皆生長在惡地海拔較高處,也就是小山丘的頂部,很是奇特(如圖二)。
資料顯示,月世界惡地由泥岩組成,泥岩是由密度大的細小顆粒組成(主成分為黏土礦物及泥漿),其滲透性是優是劣?老師拋出這個問題讓我們思考。理論上因密度大,分子間空間較小,滲透性應該較差,但要如何確定想法符合現實呢?難得有機會能直接觀察岩石,加上存在心中的實驗精神,我們決定直接拿水倒到岩石上實驗。一開始倒下,水並未直接滲入接觸的岩石,反倒有些流動,接著才慢慢滲透進岩石中,從圖三那一片濕掉的表面,可以看出水先流動才滲入岩石中,顯示結果與原思考的答案一致。野外實習重要的不只是能親眼觀察課本所學,更棒的是有機會實際實驗,應證所學!
最後,謝謝老師帶我們進行此次參訪,不管是地點或其他細節安排,都可以感受到老師的細心和熱忱!而月世界以芭蕉作為起頭,即便有微量元素,大家還是吃得很開心。接下來到月世界裡面參訪,謝謝老天爺賞臉,讓雨滴在快結束時才落下,一路陰天讓參訪的氣溫非常舒服,很適合踏青。之後就到教授介紹地質的環節,月世界的地質真的很特別,因為鹽分過高所以長不出植物,或因為有新的沈積物堆積,長出來的新植物都讓人驚嘆大自然的奧妙!此外,整個環境都讓人讚嘆大自然的鬼斧神工,白色的山脈在天際線展開,特殊的景觀讓大家流連忘返!此行不但學到課本內的知識,還能應用在實際生活上,收穫滿滿!!再次感謝教授安排這次的校外參訪,希望下次還有機會!
With the petrology class, we went on a field excursion to Tian Liao moon world (月世界) in Kaohsiung. The purpose of this tour was to study and learn more about the unique rock formations and the unique atmosphere of this place.
The plant life was truly remarkable, and there is a surprising amount of vegetation given the hot and dry conditions that are prevalen, although this area is unusual due to the numerous rock formations along the route. This was especially true of the badlands that span the plains.
As we were told, this area was once completely covered under water. As a result of climate change, the water levels have since dropped, but the groundwater is still present in some locations along the route. However, it was clarified that the water might not be apparent in its typical form and instead appear as warm mud springs.
The location was thoroughly explained by our teacher who also included interactive questioning sessions to gauge how well we understood it. Additionally, we got the chance to conduct a mini experiment, which to determine the density and permeability of the region and come to the supporting conclusions.
Unquestionably, Tian Liao moon world is a unique location for exploration, and this is a life-changing educational experience that reveals Taiwan’s natural beauties.