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作者系中山大学原地理系主任、教授，丹霞地貌旅游开发研究会终身名誉会长。

Huang Jin

Former head and professor Geography De-partment of Sun Yat-sen University and per-manent honorary president of Danxia Land-form Tourism and Exploitation Society

2013年4月20日，我在江西广丰县考察丹霞地貌时，高兴地与杨志同志认识。他赠送《龙源峡神韵》摄影作品集一册给我。该作品集十分精美，使我留下很深刻的印象。当时，杨志同志还告诉我，要出版一册江西丹霞地貌摄影作品集。这是一件重要的大好事。我当即给他复印了我编写的《中国丹霞地貌简表》（有关江西省丹霞地貌这一部分）给他参考。

江西丹霞地貌的形成可追溯到距今一亿年左右的下白垩世晚期与上白垩世早期之间的一次造山运动（燕山运动的第一幕）。该次运动，在中国东南部等地区造成不少北东——北北东向的断陷或拗陷山间盆地。江西的许多红盆地就是这些山间盆地的一部分。这些盆地四周由老岩层及不同时期的花岗岩、火山岩形成的山地、丘陵为盆地的堆积提供了物质来源。当时的气候较为干燥，氧化作用较强，使泥沙中的FeO2氧化成为红色的Fe2O3，使盆地中的泥、砂、砾石都成为红色。经压实、胶结成岩之后，便成为今日所见到的红色砾岩、红色砂砾岩、红色砂岩、红色砂泥岩、红色粉砂岩等红色岩层（简称为红层），构成江西丹霞地貌的物质基础。

在距今6700万年左右的晚白垩世晚期至古近纪早期之间，又发生一次造山运动（喜马拉雅运动的一幕），中国大陆南部受太平洋板块和印度板块的挤压发生大面积抬升，使上述的红色岩层发生倾斜并产生一系列不同方向的节理（裂隙破坏岩层的连续性，裂隙两边的岩层没有相对移动）、裂隙。并使江西不少山间内流沉积红盆地转变成为外流侵蚀地区。但在江西境内仍有相当一部分山间内流沉积红盆地继续沉积了古近纪的红色岩层。直至古近纪晚期至新近纪早期的一次造山运动（喜马拉雅运动的一幕）才使这些古近纪的山间红盆地转变成为外流侵蚀地区。这些外流侵蚀的红岩地区，在水流沿红岩的节理、裂隙进行侵蚀、剥蚀及崩塌、风化等外力作用下，开始形成有丹崖赤壁的丹霞地貌。经过古近纪及新近纪6000多万年漫长岁月的侵蚀、剥蚀、崩塌、风化及多次地壳间歇性上升，过去产生的丹霞地貌已消失，又继续产生新的丹霞地貌，目前所见到的江西丹霞地貌，仅是江西丹霞地貌漫长岁月发育过程中的一个片段。

我是一位长期研究中国丹霞地貌的学者，对杨志同志的《醉丹霞》中十七处丹霞地貌，都曾前往实地进行考察研究，有的还考察多次或作了较长时间的考察，对丹霞山、武夷山、崀山、石城、广丰等地丹霞地貌的研究还出版了专书，书中除对上诉丹霞地貌区的地貌作了较详的论述之外，还对该区的地壳上升速率、地貌年龄、岩壁后退速率及侵蚀速率等方面作了定量测算。今日，览赏了杨志同志《醉丹霞》中我以前考察过的丹霞地貌摄影作品，倍感亲切！

迄今为止，中国已发现丹霞地貌995处，其中江西省最多，有175处（占全国丹霞地貌的17.6%），是中国丹霞地貌最多的一个省。省内有不少丹霞地貌是革命老区，是老一辈无产阶级革命家战斗过、生活过的地方，也是杨志同志生长、工作的热土。我希望杨志同志能继续努力，多出版几册更丰富、质量更高的江西丹霞地貌摄影作品集。这是我殷切的希望。

2013年11月21日于广州中山大学

It was on April 20th, 2013 I got acquainted, to my pleasure, with Yang Zhi when I was on a field investigation of Danxia Landform in Guangfeng County, Jiangxi Province. He gave me his album Glamor of Longyuan Gorge, which is exquisitely printed and I was really impressed. He told me he would publish a photograph collection of Jiangxi's Danxia Landform. That's really something, so I gave him photocopy of chapters about Danxia Landform in Jiangxi from my book Briefing on China's Danxia Landform.

The formation of Danxia Landform in Jiangxi can be traced back to an orogenesis happened about 100 million years ago between late Upper Contaceous to early Lower Contaceous(the be-ginning of Yanshan Movement), which caused a number of northeast to north subsidence and basins in southeast China. Many red basin in Jiangxi are a part of these mountain basin. And the neighboring hills formed with ancient strata and granite and volcanic rock of different periods provided prerequisite for the accumulation of these basins. The draught and oxidization trans-formed the FeO2 in the sand into red Fe2O3 and thus making the sand and stones red. After being pushed tight, they become the red strata you're seeing nowadays.

Another orogenesis happened 67 million years ago between the late Contaceous and early Paleogene(a part of the Himalayas Movement), the south China mainland was raised to a great extent because of the extrusion of Pacific Plate and Indian Plate. The above mentioned red strata were tilted and texture and cracks of different directions have been made. A lot of inward sendi-mentary red basins in Jiangxi had, as a result, been transformed into outward eroded areas. Red strata can still be found in some of the inward sendimentary red basins in Jiangxi. They were not

transform into outward eroded areas until a orogenesis of late Paleogene. The outward eroded red strata began to be made into Danxia Landform with the joint action of erosion, corrosion, collapse and weathering. After these action for more than 60 million years, the old Danxia Landform dis-appeared and new ones came into being. The ones you're witnessing is but a short chapter in the long development.

I've been long engaged in the research of China's Danxia Landform and had field investiga-tion to the 17 sites of Danxia Landform taken in his Intoxicated by Danxia, long-term research for some of the sites and books for Danxia Landform in Danxia Mountain, Wuyi Mountain, Lang-shan Mountain, Shicheng and Guangfeng, which not only give thorough and detailed description of the above mentioned areas but also made calculations of the rising rate, landform history, re-treating rate and erosion rate. That's why I have a close feeling when I found pictures of sites I've been to in his album.

Up to now 995 sites of Danxia Landform have been found in China among which Jiangxi boasts the most, i.e. 175 sites and 17.6% of the total. Many sites of Danxia Landform in Jiangxi are located in old revolutionary base areas where many revolutionists including Yang Zhi once worked and battled. I sincerely hope Yang would work on and publish more and better such album in the future.

Huang Jin

In Guangzhou Sun Yat-sen University on Nov. 21th, 2013