觀(guan)音(yin)山(Kuan-yin Mountain),舊稱新宜山,別名(ming)八里坌山(淡水(shui)廳志載(zai))。位于臺灣省新北市五股(gu)區(qu)(qu)(qu)、八里區(qu)(qu)(qu)交(jiao)界,海拔標高616米(mi),由淡水(shui)河(he)北岸向南(nan)遙(yao)望,全(quan)區(qu)(qu)(qu)有十(shi)八連(lian)峰,區(qu)(qu)(qu)內有多座古剎,更增(zeng)添觀(guan)音(yin)山的(de)靈性,其中有數(shu)間供(gong)奉觀(guan)世音(yin)菩薩的(de)觀(guan)音(yin)寺。
觀(guan)音(yin)山,亦有不少納骨塔及(ji)墓園錯落其間,該山西臨臺(tai)灣海(hai)峽,東(dong)北(bei)隔淡水河遠(yuan)望關(guan)渡,昔日(ri)的“坌嶺吐霧(wu)”為淡水八大景(jing)之一,山頂又(you)稱“硬漢(han)嶺”,全山屬北(bei)海(hai)岸及(ji)觀(guan)音(yin)山風景(jing)區。
觀(guan)(guan)音(yin)山(shan)(shan)自古(gu)便有登(deng)山(shan)(shan)活動,目前八里登(deng)觀(guan)(guan)音(yin)山(shan)(shan)的路(lu)(lu)線(xian)共有四條(tiao)主(zhu)要路(lu)(lu)線(xian),其中以乘車至(zhi)觀(guan)(guan)音(yin)山(shan)(shan)風景區(qu)管理(li)處,由凌云禪寺(si)旁鐵漢(han)(han)步道經(jing)硬漢(han)(han)嶺(ling)(ling)拾(shi)階而(er)上登(deng)頂(ding)(ding)為(wei)(wei)最熱門路(lu)(lu)線(xian)。硬漢(han)(han)嶺(ling)(ling)為(wei)(wei)1961年憲兵學(xue)(xue)校(xiao)300名學(xue)(xue)員開(kai)辟了一條(tiao)直達山(shan)(shan)頂(ding)(ding)的登(deng)山(shan)(shan)步道,為(wei)(wei)鼓(gu)勵學(xue)(xue)員學(xue)(xue)硬漢(han)(han)而(er)來作硬漢(han)(han)而(er)去,而(er)名硬漢(han)(han)嶺(ling)(ling)。
硬漢嶺為火山碎屑巖與凝灰角礫(li)巖所構成(cheng),1992,1993年來時有(you)豪雨山崩土石滑動,步道(dao)毀(hui)壞并危及凌云禪(chan)寺安(an)全(quan)。寄望能(neng)有(you)效妥(tuo)當的維護整修以保(bao)持靈(ling)山古(gu)剎之(zhi)原有(you)古(gu)樸韻味。
由于季風吹來臺(tai)灣海峽的(de)水汽,遇到觀音山嶺(ling)的(de)阻擋(dang),便降下(xia)化為云(yun)霧(wu),有如飄綿滾(gun)絮、變(bian)幻無常,蔚(yu)為奇觀.被文人雅士命名(ming)為“坌嶺(ling)吐霧(wu)”,名(ming)列(lie)清代淡北八(ba)(ba)景之一。同(tong)治年間(jian)大(da)龍(long)峒舉人陳維英曾(ceng)題(ti)詩贊曰:“坌嶺(ling)微茫八(ba)(ba)里(li)間(jian),連朝(chao)吐霧(wu)罩(zhao)鴉(ya)鬟,此中定有深藏貌,未許分明(ming)見一斑”。
觀(guan)音(yin)(yin)山(shan)(shan)在淡水(shui)河(he)河(he)口南畔,東(dong)與大屯(tun)山(shan)(shan)群峰隔河(he)相峙,西南毗接林口臺地。形似仰臥之(zhi)觀(guan)音(yin)(yin),山(shan)(shan)頂空(kong)曠怡人,立(li)足其上可(ke)俯瞰河(he)口及(ji)淡水(shui)鎮(zhen)、臺北市郊景(jing)色(se),為(wei)淡水(shui)八景(jing)之(zhi)一(yi)。凌(ling)云古(gu)剎坐落山(shan)(shan)腰,后另建(jian)新廟于古(gu)剎后方約數百公尺處(chu)(即(ji)觀(guan)音(yin)(yin)山(shan)(shan)腹),名(ming)曰(yue)凌(ling)云禪寺,是(shi)游人休憩處(chu)。
觀音(yin)山(shan)為一錐(zhui)狀火(huo)(huo)(huo)(huo)山(shan),是大屯火(huo)(huo)(huo)(huo)山(shan)匯最西的(de)(de)一部分,其北(bei)側(ce)以(yi)火(huo)(huo)(huo)(huo)山(shan)熔巖(yan)(yan)(yan)為主(zhu)(zhu),南側(ce)以(yi)火(huo)(huo)(huo)(huo)山(shan)碎(sui)屑流(liu)為主(zhu)(zhu),火(huo)(huo)(huo)(huo)成(cheng)巖(yan)(yan)(yan)以(yi)安山(shan)巖(yan)(yan)(yan)為主(zhu)(zhu),另(ling)外含有一些早期(qi)噴發的(de)(de)玄(xuan)武(wu)巖(yan)(yan)(yan),越晚期(qi)的(de)(de)噴發則(ze)形(xing)成(cheng)含角閃石的(de)(de)安山(shan)巖(yan)(yan)(yan)。淡水(shui)河沿著觀音(yin)山(shan)麓流(liu)入(ru)臺灣海峽,因兩側(ce)的(de)(de)火(huo)(huo)(huo)(huo)山(shan)熔巖(yan)(yan)(yan)與(yu)碎(sui)屑物漫流(liu)入(ru)海,而形(xing)成(cheng)火(huo)(huo)(huo)(huo)山(shan)海岸。
山(shan)(shan)上(shang)(shang)(shang)坐(zuo)落(luo)著(zhu)不少名剎古寺,并可(ke)溯溪(xi)觀(guan)(guan)瀑、觀(guan)(guan)鷹賞鳥、眺望半個臺北和(he)壯麗的(de)(de)大屯(tun)山(shan)(shan)列,是(shi)一處豐富(fu)的(de)(de)自然觀(guan)(guan)賞去處。觀(guan)(guan)音山(shan)(shan)上(shang)(shang)(shang)的(de)(de)山(shan)(shan)徑(jing)溪(xi)谷(gu)四通八達,登(deng)(deng)山(shan)(shan)路線林(lin)林(lin)總(zong)總(zong)、難易不同,登(deng)(deng)山(shan)(shan)客可(ke)以(yi)揀挑適合自己體力的(de)(de)山(shan)(shan)徑(jing)上(shang)(shang)(shang)山(shan)(shan)。其中最大眾(zhong)化的(de)(de)路線是(shi)從五股的(de)(de)觀(guan)(guan)音山(shan)(shan)站牌(pai)出(chu)發(fa),沿山(shan)(shan)階上(shang)(shang)(shang)登(deng)(deng)凌云(yun)禪(chan)寺,再(zai)由寺后的(de)(de)牌(pai)樓往上(shang)(shang)(shang)走(zou),約1小(xiao)時可(ke)抵硬漢嶺。在此登(deng)(deng)高眺覽(lan),視(shi)野遼闊,整個臺北市自新光大樓以(yi)北的(de)(de)市景(jing)都在眼下,而對面(mian)的(de)(de)大屯(tun)山(shan)(shan)列及淡水河口山(shan)(shan)海相(xiang)映的(de)(de)景(jing)象更是(shi)壯觀(guan)(guan)。
白天上(shang)觀(guan)音山,可隔著(zhu)門墻(qiang)老樹感(gan)受楞嚴閣、開山院的(de)古樸莊嚴,遠眺淡水八景之一(yi)的(de)“坌領(ling)吐霧”;傍(bang)晚(wan)時分坐觀(guan)落日晚(wan)霞,淡水暮色最(zui)令人(ren)心動;或于夜幕(mu)低垂時看淡水河畔夜景,萬家燈火閃爍(shuo)明滅,另(ling)有(you)一(yi)番擾攘(rang)人(ren)間(jian)之美。
在荷蘭人(ren)(ren)統治時代(dai),觀(guan)音山叫淡水山(出現在1654年荷蘭人(ren)(ren)‘淡水與其附(fu)近村社暨雞籠(long)島(dao)略圖’中編號37的Tamswijse berch),但漢人(ren)(ren)習稱八(ba)里分(坌(ben))山,系因山邊的原住民部落八(ba)里坌(ben)社而得(de)名。
康(kang)熙年(nian)間,乃延用八里坌(ben)山(shan)(shan)的地名(ming)(康(kang)熙二十四(si)年(nian)蔣毓(yu)英“臺(tai)灣府志”)。清(qing)朝雍正年(nian)間(西元1710年(nian)代(dai))也(ye)曾改為“興(xing)直山(shan)(shan)”,但在(zai)各地方史籍中仍以(yi)“八里坌(ben)山(shan)(shan)”稱(cheng)之(zhi)。后來改為觀(guan)音(yin)山(shan)(shan)的說(shuo)(shuo)法(fa)有二:一說(shuo)(shuo)是乾隆17年(nian)(西元1752年(nian))客(ke)家籍貢生胡焯猷(福建汀州永定人)在(zai)山(shan)(shan)路西云(yun)(yun)巖籌建大(da)士觀(guan)(今五股區西云(yun)(yun)巖寺)而得名(ming),一說(shuo)(shuo)是由于山(shan)(shan)棱(leng)起(qi)伏(fu)變(bian)化,從(cong)關渡一帶眺望時,山(shan)(shan)型起(qi)伏(fu)貌似觀(guan)音(yin)菩薩(sa)的面容(rong)仰天的側面而得名(ming)。
據臺(tai)灣著(zhu)名的(de)地(di)(di)名學者-陳國章(zhang)教授所著(zhu)的(de)臺(tai)灣地(di)(di)名詞(ci)典,認為(wei)該地(di)(di)的(de)地(di)(di)名是因“形似觀音(yin)菩薩(sa)的(de)山”而得名。
1937年12月27日(ri)(ri),日(ri)(ri)本(ben)殖民當局以(yi)臺灣寶島(dao)山(shan)(shan)水風(feng)光(guang)秀麗籌劃成立大屯觀音山(shan)(shan)、次高山(shan)(shan)太魯閣和新高阿(a)里(li)山(shan)(shan)三座公園(yuan),并于(yu)1941年3月10日(ri)(ri)發行紀念郵票、小全張及臺灣公園(yuan)寫真集,可惜因戰爭而(er)延宕。
二次世界(jie)大戰結束后,臺灣(wan)回歸中國,觀(guan)音山優良的屏(ping)障(zhang)、視野(ye)的寬(kuan)闊好(hao)山好(hao)水,為(wei)(wei)國人所認為(wei)(wei)風水寶地,濫挖濫葬,一片零(ling)亂有礙視野(ye)觀(guan)瞻。相(xiang)較之(zhi)下,景觀(guan)資(zi)源大不如往昔,已(yi)失去了成為(wei)(wei)公園之(zhi)基(ji)本要件,十(shi)分可惜。
觀(guan)音(yin)山(shan)是臺灣北(bei)部(bu)火成(cheng)巖區中(zhong)最西北(bei)側(ce)(ce)之(zhi)火山(shan)單(dan)元,以淡水河(he)與大屯火山(shan)群遙遙相望,基本上為單(dan)一中(zhong)心(xin)噴發(fa)的火山(shan)碎(sui)屑、凝(ning)灰巖與熔巖交替組成(cheng)之(zhi)復式火山(shan)。觀(guan)音(yin)山(shan)火山(shan)之(zhi)主體可能是一中(zhong)央噴發(fa)之(zhi)錐(zhui)狀火山(shan),錐(zhui)體半(ban)(ban)徑約1~2公里,噴發(fa)中(zhong)心(xin)在觀(guan)音(yin)山(shan)主峰(feng)之(zhi)東南方。在凌云山(shan)一帶(dai)之(zhi)半(ban)(ban)環形之(zhi)連峰(feng)可能是火山(shan)口壁之(zhi)西側(ce)(ce)。
在(zai)此以(yi)(yi)東(dong)(dong),于(yu)石(shi)(shi)(shi)壁坑附(fu)近之(zhi)地(di)形,呈(cheng)馬(ma)蹄狀之(zhi)半(ban)圓形凹陷可能(neng)是火(huo)山(shan)(shan)(shan)(shan)口(kou)所在(zai),但火(huo)山(shan)(shan)(shan)(shan)口(kou)之(zhi)東(dong)(dong)壁已(yi)經爆(bao)破或熔巖(yan)(yan)溢流(liu)巖(yan)(yan)漿庫匱空塌陷而崩(beng)塌,其部(bu)分碎屑(xie)構成分布于(yu)凌云山(shan)(shan)(shan)(shan)以(yi)(yi)東(dong)(dong)地(di)區之(zhi)集(ji)塊巖(yan)(yan)或原先之(zhi)火(huo)山(shan)(shan)(shan)(shan)碎屑(xie)流(liu)與(yu)火(huo)山(shan)(shan)(shan)(shan)礫巖(yan)(yan)。觀音(yin)山(shan)(shan)(shan)(shan)火(huo)山(shan)(shan)(shan)(shan)活動時可能(neng)不猛烈,因而出(chu)露(lu)之(zhi)主體并(bing)未含有可觀的(de)火(huo)山(shan)(shan)(shan)(shan)碎屑(xie)巖(yan)(yan),仍以(yi)(yi)厚層的(de)巖(yan)(yan)流(liu)為主。觀音(yin)山(shan)(shan)(shan)(shan)噴出(chu)熔巖(yan)(yan)流(liu)也和(he)(he)大屯(tun)火(huo)山(shan)(shan)(shan)(shan)群(qun)相似,均以(yi)(yi)安山(shan)(shan)(shan)(shan)巖(yan)(yan)為主。一般安山(shan)(shan)(shan)(shan)巖(yan)(yan)常呈(cheng)灰(hui)或灰(hui)黑色,且多呈(cheng)斑狀結(jie)構,由結(jie)晶(jing)較(jiao)粗大之(zhi)斑晶(jing)散布在(zai)石(shi)(shi)(shi)質細(xi)密(mi)之(zhi)石(shi)(shi)(shi)基中(zhong)。斑晶(jing)礦(kuang)物以(yi)(yi)鎂鐵礦(kuang)物為多,包括橄欖石(shi)(shi)(shi)、輝石(shi)(shi)(shi)、紫蘇輝石(shi)(shi)(shi)、角閃(shan)石(shi)(shi)(shi)、黑云母等(deng)礦(kuang)物,此外還有灰(hui)白(bai)色的(de)斜長(chang)石(shi)(shi)(shi)。石(shi)(shi)(shi)基以(yi)(yi)斜長(chang)石(shi)(shi)(shi)和(he)(he)一些鎂鐵礦(kuang)物的(de)微晶(jing)(肉(rou)眼不能(neng)分辨(bian)的(de))和(he)(he)無(wu)結(jie)晶(jing)的(de)火(huo)山(shan)(shan)(shan)(shan)玻璃所組成。
本區安山巖熔(rong)巖依噴發(fa)之先后,由下而上(shang)可分別為(wei)三層,各層巖石在組織上(shang)和成分上(shang)都(dou)有(you)多少(shao)不同(tong)。
底層(ceng)(或(huo)(huo)第一(yi)層(ceng))是粗粒普通(tong)輝(hui)(hui)(hui)石(shi)(shi)玄(xuan)武(wu)巖(yan)或(huo)(huo)玄(xuan)武(wu)巖(yan)質安(an)山(shan)(shan)巖(yan)熔(rong)巖(yan)。主(zhu)要(yao)露(lu)出(chu)于(yu)火(huo)山(shan)(shan)錐體(ti)之(zhi)(zhi)中心地帶,包括石(shi)(shi)壁坑及其東側(ce)之(zhi)(zhi)米(mi)倉村、烏(wu)山(shan)(shan)頭,至福隆山(shan)(shan)等地。安(an)山(shan)(shan)巖(yan)顏(yan)色(se)深灰(hui),呈斑(ban)狀結構有許多(duo)(duo)黑(hei)綠色(se)之(zhi)(zhi)普通(tong)輝(hui)(hui)(hui)石(shi)(shi)斑(ban)晶(jing)(jing),散布在灰(hui)色(se)細(xi)晶(jing)(jing)之(zhi)(zhi)石(shi)(shi)基(ji)中,斑(ban)晶(jing)(jing)大(da)者(zhe)可達5公里左(zuo)右。在顯微鏡下觀(guan)察(cha)巖(yan)石(shi)(shi)薄(bo)片(pian),這些斑(ban)晶(jing)(jing)多(duo)(duo)成雙晶(jing)(jing)或(huo)(huo)叢晶(jing)(jing)(由數(shu)個晶(jing)(jing)體(ti)結集而成),輝(hui)(hui)(hui)石(shi)(shi)之(zhi)(zhi)外還有多(duo)(duo)數(shu)斜(xie)長(chang)石(shi)(shi)和少(shao)數(shu)橄欖石(shi)(shi)。中層(ceng)(或(huo)(huo)第二層(ceng))的(de)熔(rong)巖(yan)是由兩(liang)輝(hui)(hui)(hui)安(an)山(shan)(shan)巖(yan)構成。巖(yan)石(shi)(shi)外觀(guan)灰(hui)色(se),普通(tong)輝(hui)(hui)(hui)石(shi)(shi)之(zhi)(zhi)斑(ban)晶(jing)(jing)雖粗大(da)易見但(dan)甚(shen)稀少(shao),細(xi)長(chang)之(zhi)(zhi)紫(zi)蘇(su)輝(hui)(hui)(hui)石(shi)(shi)晶(jing)(jing)體(ti)頗多(duo)(duo)但(dan)均細(xi)小。本(ben)巖(yan)石(shi)(shi)之(zhi)(zhi)石(shi)(shi)基(ji)占量較多(duo)(duo),由斜(xie)長(chang)石(shi)(shi)和紫(zi)蘇(su)輝(hui)(hui)(hui)石(shi)(shi)細(xi)晶(jing)(jing)以及火(huo)山(shan)(shan)玻璃所(suo)組成。本(ben)層(ceng)是觀(guan)音山(shan)(shan)中露(lu)出(chu)面積最廣(guang)的(de)熔(rong)巖(yan),主(zhu)要(yao)分(fen)布于(yu)觀(guan)音山(shan)(shan)主(zhu)峰北側(ce)之(zhi)(zhi)山(shan)(shan)坡。
第二層(ceng)(ceng)(ceng)斑晶(jing)(jing)(jing)(jing)稀疏(shu)之(zhi)(zhi)(zhi)兩(liang)輝(hui)(hui)(hui)安山(shan)(shan)(shan)(shan)(shan)(shan)巖(yan)(yan)(yan)(yan)(yan)(yan),常(chang)含第一(yi)(yi)層(ceng)(ceng)(ceng)輝(hui)(hui)(hui)石(shi)(shi)(shi)斑晶(jing)(jing)(jing)(jing)多(duo)而聚(ju)集(ji)成叢的(de)(de)(de)普通輝(hui)(hui)(hui)石(shi)(shi)(shi)安山(shan)(shan)(shan)(shan)(shan)(shan)巖(yan)(yan)(yan)(yan)(yan)(yan)之(zhi)(zhi)(zhi)捕獲(huo)巖(yan)(yan)(yan)(yan)(yan)(yan)塊(kuai),根據年代(dai)對比的(de)(de)(de)包裹定(ding)律(lv),即可(ke)知其(qi)(qi)發生之(zhi)(zhi)(zhi)先后順序,乃(nai)輝(hui)(hui)(hui)石(shi)(shi)(shi)安山(shan)(shan)(shan)(shan)(shan)(shan)巖(yan)(yan)(yan)(yan)(yan)(yan)(第一(yi)(yi)層(ceng)(ceng)(ceng))早于(yu)兩(liang)輝(hui)(hui)(hui)安山(shan)(shan)(shan)(shan)(shan)(shan)巖(yan)(yan)(yan)(yan)(yan)(yan)(第二層(ceng)(ceng)(ceng))。頂層(ceng)(ceng)(ceng)(第三層(ceng)(ceng)(ceng))紫(zi)蘇(su)輝(hui)(hui)(hui)石(shi)(shi)(shi)安山(shan)(shan)(shan)(shan)(shan)(shan)巖(yan)(yan)(yan)(yan)(yan)(yan)與一(yi)(yi)部(bu)分(fen)(fen)角閃石(shi)(shi)(shi)紫(zi)蘇(su)安山(shan)(shan)(shan)(shan)(shan)(shan)巖(yan)(yan)(yan)(yan)(yan)(yan)為其(qi)(qi)特征,顏(yan)色(se)淡(dan)灰(hui)色(se)或(huo)(huo)(huo)灰(hui)紫(zi),斑晶(jing)(jing)(jing)(jing)細小不顯(xian)著。有(you)時可(ke)見有(you)細長(chang)之(zhi)(zhi)(zhi)紫(zi)蘇(su)輝(hui)(hui)(hui)石(shi)(shi)(shi)或(huo)(huo)(huo)角閃石(shi)(shi)(shi)之(zhi)(zhi)(zhi)小晶(jing)(jing)(jing)(jing),石(shi)(shi)(shi)基較多(duo)包含微(wei)晶(jing)(jing)(jing)(jing)與玻璃(li)質。本層(ceng)(ceng)(ceng)主(zhu)要(yao)分(fen)(fen)布在火(huo)(huo)山(shan)(shan)(shan)(shan)(shan)(shan)中(zhong)(zhong)(zhong)央之(zhi)(zhi)(zhi)頂部(bu),由觀音(yin)山(shan)(shan)(shan)(shan)(shan)(shan)主(zhu)峰至崩(beng)山(shan)(shan)(shan)(shan)(shan)(shan)一(yi)(yi)帶。在本地區內除上(shang)(shang)述之(zhi)(zhi)(zhi)三層(ceng)(ceng)(ceng)熔巖(yan)(yan)(yan)(yan)(yan)(yan)流之(zhi)(zhi)(zhi)外,還有(you)兩(liang)處獨(du)立之(zhi)(zhi)(zhi)小規模(mo)火(huo)(huo)山(shan)(shan)(shan)(shan)(shan)(shan)巖(yan)(yan)(yan)(yan)(yan)(yan)體(ti),一(yi)(yi)是(shi)(shi)(shi)在觀音(yin)山(shan)(shan)(shan)(shan)(shan)(shan)站北側(ce)公(gong)路旁(pang)出(chu)(chu)露(lu)之(zhi)(zhi)(zhi)黑(hei)云母(mu)角閃安山(shan)(shan)(shan)(shan)(shan)(shan)巖(yan)(yan)(yan)(yan)(yan)(yan)脈,為一(yi)(yi)厚約20~40公(gong)尺之(zhi)(zhi)(zhi)脈狀小侵入(ru)體(ti)(或(huo)(huo)(huo)稱觀音(yin)坑巖(yan)(yan)(yan)(yan)(yan)(yan)脈),穿入(ru)觀音(yin)山(shan)(shan)(shan)(shan)(shan)(shan)層(ceng)(ceng)(ceng)之(zhi)(zhi)(zhi)粉(fen)砂巖(yan)(yan)(yan)(yan)(yan)(yan)之(zhi)(zhi)(zhi)中(zhong)(zhong)(zhong)。另一(yi)(yi)處是(shi)(shi)(shi)突出(chu)(chu)于(yu)成子寮附(fu)近低地上(shang)(shang)之(zhi)(zhi)(zhi)萬年塔小山(shan)(shan)(shan)(shan)(shan)(shan),巖(yan)(yan)(yan)(yan)(yan)(yan)石(shi)(shi)(shi)是(shi)(shi)(shi)橄欖(lan)(lan)石(shi)(shi)(shi)玄武(wu)巖(yan)(yan)(yan)(yan)(yan)(yan),可(ke)能(neng)是(shi)(shi)(shi)一(yi)(yi)火(huo)(huo)山(shan)(shan)(shan)(shan)(shan)(shan)側(ce)噴發之(zhi)(zhi)(zhi)巖(yan)(yan)(yan)(yan)(yan)(yan)體(ti)。萬年塔所產出(chu)(chu)者(zhe),其(qi)(qi)橄欖(lan)(lan)石(shi)(shi)(shi)含量較普通輝(hui)(hui)(hui)石(shi)(shi)(shi)為多(duo),與福隆山(shan)(shan)(shan)(shan)(shan)(shan)玄武(wu)巖(yan)(yan)(yan)(yan)(yan)(yan)略有(you)不同。根據結(jie)晶(jing)(jing)(jing)(jing)分(fen)(fen)化的(de)(de)(de)效(xiao)應(ying),玄武(wu)質巖(yan)(yan)(yan)(yan)(yan)(yan)漿經由橄欖(lan)(lan)石(shi)(shi)(shi)、輝(hui)(hui)(hui)石(shi)(shi)(shi)與斜長(chang)石(shi)(shi)(shi)的(de)(de)(de)結(jie)晶(jing)(jing)(jing)(jing)分(fen)(fen)化可(ke)以產生安山(shan)(shan)(shan)(shan)(shan)(shan)巖(yan)(yan)(yan)(yan)(yan)(yan)。同樣的(de)(de)(de)由混染作(zuo)(zuo)用,也(ye)就是(shi)(shi)(shi)由基性(xing)的(de)(de)(de)巖(yan)(yan)(yan)(yan)(yan)(yan)漿與酸性(xing)的(de)(de)(de)巖(yan)(yan)(yan)(yan)(yan)(yan)漿混合,或(huo)(huo)(huo)是(shi)(shi)(shi)由玄武(wu)質巖(yan)(yan)(yan)(yan)(yan)(yan)漿,混雜(za)了沈(shen)積物或(huo)(huo)(huo)地殼(ke)物質都可(ke)能(neng)衍生成安山(shan)(shan)(shan)(shan)(shan)(shan)巖(yan)(yan)(yan)(yan)(yan)(yan)。在觀音(yin)山(shan)(shan)(shan)(shan)(shan)(shan)地區安山(shan)(shan)(shan)(shan)(shan)(shan)巖(yan)(yan)(yan)(yan)(yan)(yan)或(huo)(huo)(huo)玄武(wu)巖(yan)(yan)(yan)(yan)(yan)(yan)中(zhong)(zhong)(zhong),常(chang)含有(you)火(huo)(huo)山(shan)(shan)(shan)(shan)(shan)(shan)體(ti)基底的(de)(de)(de)砂巖(yan)(yan)(yan)(yan)(yan)(yan)或(huo)(huo)(huo)硅質片巖(yan)(yan)(yan)(yan)(yan)(yan),顯(xian)示地殼(ke)物質的(de)(de)(de)混染作(zuo)(zuo)用具(ju)有(you)舉足輕重的(de)(de)(de)角色(se)。
觀(guan)(guan)音山(shan)(shan)(shan)(shan)(shan)各火(huo)(huo)(huo)山(shan)(shan)(shan)(shan)(shan)體的噴(pen)發(fa)時代,根據鉀-氬(ya)法(fa)定年(nian)的結果來看,觀(guan)(guan)音山(shan)(shan)(shan)(shan)(shan)火(huo)(huo)(huo)山(shan)(shan)(shan)(shan)(shan)之活動盛行于(yu)第(di)四紀。由六十(shi)余(yu)萬(wan)年(nian)前(qian)開(kai)始;接著是五十(shi)余(yu)萬(wan)年(nian)前(qian)底層輝(hui)(hui)石玄武(wu)巖(yan)或玄武(wu)巖(yan)質(zhi)熔巖(yan)之噴(pen)發(fa);其次(ci)則為四十(shi)余(yu)萬(wan)年(nian)前(qian),第(di)二層兩輝(hui)(hui)安(an)山(shan)(shan)(shan)(shan)(shan)巖(yan);再依次(ci)為三十(shi)余(yu)萬(wan)年(nian)前(qian)第(di)三層紫蘇輝(hui)(hui)石與紫蘇輝(hui)(hui)石角閃(shan)安(an)山(shan)(shan)(shan)(shan)(shan)巖(yan)之噴(pen)發(fa);最后以二十(shi)余(yu)萬(wan)年(nian)前(qian)橄(gan)欖(lan)玄武(wu)巖(yan)落幕(mu)。由火(huo)(huo)(huo)山(shan)(shan)(shan)(shan)(shan)噴(pen)發(fa)年(nian)代與塌陷破火(huo)(huo)(huo)山(shan)(shan)(shan)(shan)(shan)口地貌看來,觀(guan)(guan)音山(shan)(shan)(shan)(shan)(shan)非為活火(huo)(huo)(huo)山(shan)(shan)(shan)(shan)(shan),有可能是座休眠(mian)火(huo)(huo)(huo)山(shan)(shan)(shan)(shan)(shan)或死火(huo)(huo)(huo)山(shan)(shan)(shan)(shan)(shan)。
1937年12月27日(ri)成立大屯(tun)公園,觀音(yin)(yin)山亦在其中。但戰后成立的(de)陽明山公園剔除觀音(yin)(yin)山(2002年方另成立北海岸(an)及觀音(yin)(yin)山風(feng)景區(qu)管理),以及民間認為(wei)(wei)此(ci)山為(wei)(wei)風(feng)水寶地,埋下日(ri)后濫墾濫葬及水土保持(chi)的(de)問(wen)題。據估計目前山上非法墓計4萬處,成為(wei)(wei)發(fa)展阻礙。