CAJ | 학술논문

珠江三角洲第四纪底部含水层当中的天异常高然铵，来自于第四纪沉积当中的有机质在厌氧条件下的矿化。珠江三角洲第四纪晚期的沉积序列，主要包括两层海相沉积层(M1和 M2)，以及两层陆相沉积层(T1和 T2)。然而，截至目前，上述地层对天然铵的生成与存储作用，尚不明确。从三角洲的内陆到近岸，选取重点钻孔BJ8、SD1、SD14和MZ4，利用准确的定年数据，以及钻孔剖面各类铵以及总有机碳等数据，探讨与比较了珠江三角洲第四纪各地层生成与储存天然铵的能力。结果表明：全新世时期的海相沉积层(M1)，具有高达17.4 g·kg-1的沉积有机质质量分数。对 SD14钻孔剖面上高精度的有机碳分析表明，M1、M2层平均有机质质量分数分别为11.7和10.1 g·kg-1。因此，相对于晚更新世时期的海相沉积层(M2)来说，全新世海相沉积层M1具备生成更多铵的能力。对SD14钻孔剖面上各类铵的分析表明，M1和M2总铵质量分数的平均值分别为0.41和0.31 g·kg-1；M1、M2和T2各地层单位面积所储存铵的平均值分别为28.6、11.25和0.34 kg·m-2。而不同地层铵含量的差异，在该研究关注的其他钻孔 BJ8，SD1和 MZ4也非常明显。因此得出结论，全新世海相沉积层M1，是主要的储铵层，而M2则是次要的储铵层。两个陆相沉积层T1和T2，不论在生铵和储铵的功能上，远远小于两个海相沉积层。在 M1层中，铵的量呈现随深度增加而升高的趋势，原因在于铵不断生成累积，并通过扩散作用向下运移。而M2层中铵的含量呈现由上至下递减的趋势，说明M2层中的铵主要来自于上部M1层的扩散，其本身生成铵的量比M1少。M1层在珠江三角洲广泛发育，M2层经过长期的风化和剥蚀，在珠江三角洲许多地方已缺失。珠江三角洲底部含水层中天然高铵的浓度，主要由M1层生成与存储的铵的总量所决定。珠江三角洲第四紀底部含水層噹中的天異常高然銨，來自于第四紀沉積噹中的有機質在厭氧條件下的礦化。珠江三角洲第四紀晚期的沉積序列，主要包括兩層海相沉積層(M1和 M2)，以及兩層陸相沉積層(T1和 T2)。然而，截至目前，上述地層對天然銨的生成與存儲作用，尚不明確。從三角洲的內陸到近岸，選取重點鑽孔BJ8、SD1、SD14和MZ4，利用準確的定年數據，以及鑽孔剖麵各類銨以及總有機碳等數據，探討與比較瞭珠江三角洲第四紀各地層生成與儲存天然銨的能力。結果錶明：全新世時期的海相沉積層(M1)，具有高達17.4 g·kg-1的沉積有機質質量分數。對 SD14鑽孔剖麵上高精度的有機碳分析錶明，M1、M2層平均有機質質量分數分彆為11.7和10.1 g·kg-1。因此，相對于晚更新世時期的海相沉積層(M2)來說，全新世海相沉積層M1具備生成更多銨的能力。對SD14鑽孔剖麵上各類銨的分析錶明，M1和M2總銨質量分數的平均值分彆為0.41和0.31 g·kg-1；M1、M2和T2各地層單位麵積所儲存銨的平均值分彆為28.6、11.25和0.34 kg·m-2。而不同地層銨含量的差異，在該研究關註的其他鑽孔 BJ8，SD1和 MZ4也非常明顯。因此得齣結論，全新世海相沉積層M1，是主要的儲銨層，而M2則是次要的儲銨層。兩箇陸相沉積層T1和T2，不論在生銨和儲銨的功能上，遠遠小于兩箇海相沉積層。在 M1層中，銨的量呈現隨深度增加而升高的趨勢，原因在于銨不斷生成纍積，併通過擴散作用嚮下運移。而M2層中銨的含量呈現由上至下遞減的趨勢，說明M2層中的銨主要來自于上部M1層的擴散，其本身生成銨的量比M1少。M1層在珠江三角洲廣汎髮育，M2層經過長期的風化和剝蝕，在珠江三角洲許多地方已缺失。珠江三角洲底部含水層中天然高銨的濃度，主要由M1層生成與存儲的銨的總量所決定。
주강삼각주제사기저부함수층당중적천이상고연안，래자우제사기침적당중적유궤질재염양조건하적광화。주강삼각주제사기만기적침적서렬，주요포괄량층해상침적층(M1화 M2)，이급량층륙상침적층(T1화 T2)。연이，절지목전，상술지층대천연안적생성여존저작용，상불명학。종삼각주적내륙도근안，선취중점찬공BJ8、SD1、SD14화MZ4，이용준학적정년수거，이급찬공부면각류안이급총유궤탄등수거，탐토여비교료주강삼각주제사기각지층생성여저존천연안적능력。결과표명：전신세시기적해상침적층(M1)，구유고체17.4 g·kg-1적침적유궤질질량분수。대 SD14찬공부면상고정도적유궤탄분석표명，M1、M2층평균유궤질질량분수분별위11.7화10.1 g·kg-1。인차，상대우만경신세시기적해상침적층(M2)래설，전신세해상침적층M1구비생성경다안적능력。대SD14찬공부면상각류안적분석표명，M1화M2총안질량분수적평균치분별위0.41화0.31 g·kg-1；M1、M2화T2각지층단위면적소저존안적평균치분별위28.6、11.25화0.34 kg·m-2。이불동지층안함량적차이，재해연구관주적기타찬공 BJ8，SD1화 MZ4야비상명현。인차득출결론，전신세해상침적층M1，시주요적저안층，이M2칙시차요적저안층。량개륙상침적층T1화T2，불론재생안화저안적공능상，원원소우량개해상침적층。재 M1층중，안적량정현수심도증가이승고적추세，원인재우안불단생성루적，병통과확산작용향하운이。이M2층중안적함량정현유상지하체감적추세，설명M2층중적안주요래자우상부M1층적확산，기본신생성안적량비M1소。M1층재주강삼각주엄범발육，M2층경과장기적풍화화박식，재주강삼각주허다지방이결실。주강삼각주저부함수층중천연고안적농도，주요유M1층생성여존저적안적총량소결정。
The highest ammonium concentration in the confined basal aquifer in the Pearl River Delta (PRD), China, was found to be 390 mg·L-1. The ammonium is naturally originated from mineralization of sedimentary organic matter under strict anaerobic conditions. Sedimentary sequences of Quaternary age in the PRD are mainly composed of two marine units (M1 and M2) and two terrestrial units (T1 and T2). This study aimed to investigate the capacity of ammonium generation in the Quaternary formations. Core samples in four key boreholes (BJ8, SD1, SD14 and MZ4) from the inland area to the coast were used to study the hydrogeochemical parameters and the ages of the sediments using deferent dating methods. The results demonstrated that M1 had high contents of sedimentary organic carbon, up to 17.4 g·kg-1. Analysis of sedimentary organic matter on the vertical profile of SD14 showed that the average sedimentary organic matter contents for M1 and M2 were 11.7 and 10.1 g·kg-1, respectively. This indicated the Holocene marine sequence M1 was able to generate larger amount of ammonium than the older marine sequence M2. Various ammonium analyses on the vertical profile of SD14 demonstrated that the average total ammonium contents for M1 and M2 were 0.41 and 0.31 g·kg-1, respectively;the average ammonium contents per unit area for M1, M2 and T2 were 28.6, 11.25 and 0.34 kg·m-2, respectively. Obvious differences of ammonium contents in different sedimentary sequences were also found to exist in other boreholes studied in this research. The above results indicated that M1 was the main sedimentary sequence for ammonium generation and preservation;M2 was the secondary sequence for ammonium generation and preservation. Total available ammonium contents in M1 increased with the depth, and this was mainly caused by ammonium accumulation and diffusion within the marine sediments. On the contrary, Total available ammonium contents in M2 decreased with the depth, indicating that significant amounts of ammonium in M2 were derived from M1. M1 was more extensively developed than M2 in the PRD. Therefore, ammonium concentrations in the confined basal aquifer were controlled mainly by the amounts of ammonium generated and stored within the overlying M1.