“金釘子(zi)”全(quan)稱為全(quan)球(qiu)性界(jie)線層型剖(pou)(pou)面(mian)和點位，是(shi)年代地(di)層系(xi)與系(xi)之間的全(quan)球(qiu)標準。長(chang)興煤(mei)山D剖(pou)(pou)面(mian)是(shi)地(di)球(qiu)發展史較大的斷(duan)代界(jie)線層型。1985年，中國(guo)地(di)質(zhi)大學教授張克信在D剖(pou)(pou)面(mian)27C之底發現(xian)了(le)牙形石化石，從(cong)而確立了(le)該剖(pou)(pou)面(mian)的國(guo)際地(di)位。
這(zhe)枚(mei)“金釘子”既是二疊系與三疊系的界線，又是古生(sheng)代(dai)(dai)和中(zhong)生(sheng)代(dai)(dai)的分界標志(zhi)，是地質年代(dai)(dai)中(zhong)較(jiao)大的3個(ge)斷代(dai)(dai)“金釘子”之一。它的發現(xian)，代(dai)(dai)表著所(suo)在國地層研究(jiu)水平的較(jiao)高科學榮譽。
長(chang)興(xing)(xing)地質遺跡保護區位(wei)于長(chang)興(xing)(xing)媒山(shan)鎮與槐坎鄉的(de)交界處，為長(chang)興(xing)(xing)灰巖剖(pou)面。1931年，美籍科學家(jia)葛利普以(yi)(yi)長(chang)興(xing)(xing)地名將長(chang)興(xing)(xing)灰巖命名為"長(chang)興(xing)(xing)階"，代表二疊(die)系較晚期(qi)的(de)一(yi)個(ge)年代地層單位(wei)，是一(yi)個(ge)以(yi)(yi)中國地名命名的(de)地層年代單位(wei)。
2001年3月(yue)，國(guo)際地科聯(lian)(lian)通(tong)過投票，正式將浙江長興(xing)灰(hui)巖的D剖(pou)(pou)面(mian)(mian)確(que)定為全(quan)球二疊(die)(die)－－三疊(die)(die)系界線層(ceng)型及點（俗(su)稱"金(jin)(jin)釘子"）。2005年9月(yue)3日，國(guo)際地科聯(lian)(lian)又在長興(xing)灰(hui)巖的同一剖(pou)(pou)面(mian)(mian)上(shang)確(que)定了全(quan)球長興(xing)階(jie)底界和吳(wu)家坪階(jie)頂(ding)界的接觸接線層(ceng)型，這意味著浙江長興(xing)媒山在同一D剖(pou)(pou)面(mian)(mian)上(shang)擁有兩顆(ke)"金(jin)(jin)釘子"。
建(jian)筑面積約4000平方米(mi)的(de)(de)(de)(de)地(di)(di)質博物館分為(wei)地(di)(di)球奧秘(mi)廳(ting)(ting)(ting)(ting)(ting)、生(sheng)(sheng)(sheng)命演化(hua)廳(ting)(ting)(ting)(ting)(ting)、研礦(kuang)形成(cheng)廳(ting)(ting)(ting)(ting)(ting)、"金釘子"展(zhan)廳(ting)(ting)(ting)(ting)(ting)、長(chang)興(xing)古(gu)(gu)(gu)(gu)地(di)(di)理廳(ting)(ting)(ting)(ting)(ting)和科普演示廳(ting)(ting)(ting)(ting)(ting)6個展(zhan)廳(ting)(ting)(ting)(ting)(ting)。將成(cheng)為(wei)中(zhong)(zhong)(zhong)(zhong)外地(di)(di)學(xue)專家科考(kao)的(de)(de)(de)(de)神(shen)圣(sheng)殿堂，大(da)專院校真實(shi)直觀的(de)(de)(de)(de)實(shi)驗基地(di)(di)，更是(shi)(shi)青少年科普教育的(de)(de)(de)(de)大(da)講壇。這些展(zhan)廳(ting)(ting)(ting)(ting)(ting)以圖(tu)文(wen)和古(gu)(gu)(gu)(gu)生(sheng)(sheng)(sheng)物化(hua)石標本等介(jie)紹地(di)(di)球生(sheng)(sheng)(sheng)命的(de)(de)(de)(de)起源，展(zhan)示長(chang)興(xing)剖面中(zhong)(zhong)(zhong)(zhong)各(ge)類化(hua)石實(shi)物和照片(pian)，并以二疊(die)世晚期長(chang)興(xing)的(de)(de)(de)(de)古(gu)(gu)(gu)(gu)地(di)(di)理環境為(wei)背(bei)景，模擬古(gu)(gu)(gu)(gu)生(sheng)(sheng)(sheng)物生(sheng)(sheng)(sheng)活(huo)場景及二疊(die)－－三疊(die)紀時期古(gu)(gu)(gu)(gu)地(di)(di)理與(yu)古(gu)(gu)(gu)(gu)生(sheng)(sheng)(sheng)態景觀。在(zai)全館中(zhong)(zhong)(zhong)(zhong)，較有意(yi)義(yi)的(de)(de)(de)(de)藏品是(shi)(shi)一顆被(bei)放大(da)的(de)(de)(de)(de)牙(ya)形石模型，這是(shi)(shi)一枚(mei)劃地(di)(di)球時代(dai)(dai)意(yi)義(yi)的(de)(de)(de)(de)標志性化(hua)石，是(shi)(shi)2.5億年前古(gu)(gu)(gu)(gu)生(sheng)(sheng)(sheng)代(dai)(dai)與(yu)中(zhong)(zhong)(zhong)(zhong)生(sheng)(sheng)(sheng)代(dai)(dai)的(de)(de)(de)(de)界(jie)限標志，成(cheng)了各(ge)國(guo)科學(xue)家翻閱的(de)(de)(de)(de)天書，被(bei)國(guo)際地(di)(di)科聯確定為(wei)全球較高級別的(de)(de)(de)(de)金釘子。長(chang)興(xing)地(di)(di)質遺跡自然保護(hu)區所擁有的(de)(de)(de)(de)全球"金釘子"是(shi)(shi)地(di)(di)球史(shi)上(shang)3個較重要的(de)(de)(de)(de)斷代(dai)(dai)界(jie)線（前古(gu)(gu)(gu)(gu)生(sheng)(sheng)(sheng)代(dai)(dai)－－古(gu)(gu)(gu)(gu)生(sheng)(sheng)(sheng)代(dai)(dai)，古(gu)(gu)(gu)(gu)生(sheng)(sheng)(sheng)代(dai)(dai)－－中(zhong)(zhong)(zhong)(zhong)生(sheng)(sheng)(sheng)代(dai)(dai)，中(zhong)(zhong)(zhong)(zhong)生(sheng)(sheng)(sheng)代(dai)(dai)－－新生(sheng)(sheng)(sheng)代(dai)(dai)）之一，即古(gu)(gu)(gu)(gu)生(sheng)(sheng)(sheng)代(dai)(dai)與(yu)中(zhong)(zhong)(zhong)(zhong)生(sheng)(sheng)(sheng)代(dai)(dai)的(de)(de)(de)(de)斷代(dai)(dai)界(jie)線；同時它又是(shi)(shi)地(di)(di)球歷史(shi)上(shang)5次生(sheng)(sheng)(sheng)物大(da)絕滅中(zhong)(zhong)(zhong)(zhong)較大(da)一次絕滅事件和全球變化(hua)相聯系的(de)(de)(de)(de)點位，具(ju)有國(guo)際對比意(yi)義(yi)和極高的(de)(de)(de)(de)科學(xue)研究(jiu)價值。
