CAJ | 학술논문

通过研究青海湖全新世硬水效应变化与大气14C浓度(Xatm)之间的关系,确定了湖水溶解无机碳(DIC)与大气14C浓度之比值(XDIC/Xatm)约为0.790.利用已知Xatm随时间变化曲线重建了青海湖全新世的硬水效应,并对沉积物年龄作了相应校正.结果表明,青海湖全新世沉积物(有机质)14C年龄偏老主要缘于湖泊硬水效应,从全新世早期的1000a左右升高到核爆近前的2300a左右,核爆效应之后2005AD又降至1500a左右,其变化至少在很大程度上受控于Xatm的波动(对应于以上3个时期,根据Xatm所恢复的硬水效应分别为1100a、2150a、13130).在此基础上,利用硬水效应校正表对青海湖全新世沉积物14C年龄进行了分阶段校正,基于此校正年龄的红度曲线较好地响应了9000-8000cal aBP、6000-5000cal aBP、4200-3800cal aBP、3500-2500cal aBP、1200-1000eal aBP和600-150cal aBP等全球性冷事件.
통과연구청해호전신세경수효응변화여대기14C농도(Xatm)지간적관계,학정료호수용해무궤탄(DIC)여대기14C농도지비치(XDIC/Xatm)약위0.790.이용이지Xatm수시간변화곡선중건료청해호전신세적경수효응,병대침적물년령작료상응교정.결과표명,청해호전신세침적물(유궤질)14C년령편로주요연우호박경수효응,종전신세조기적1000a좌우승고도핵폭근전적2300a좌우,핵폭효응지후2005AD우강지1500a좌우,기변화지소재흔대정도상수공우Xatm적파동(대응우이상3개시기,근거Xatm소회복적경수효응분별위1100a、2150a、13130).재차기출상,이용경수효응교정표대청해호전신세침적물14C년령진행료분계단교정,기우차교정년령적홍도곡선교호지향응료9000-8000cal aBP、6000-5000cal aBP、4200-3800cal aBP、3500-2500cal aBP、1200-1000eal aBP화600-150cal aBP등전구성랭사건.
The relationship between 14C levels in lake waters and in the atmosphere had been investigated by comparing the chan ges in hardwater effect ( HWE, expressed by XDIC; X: percent modem carbon; DIC: abbreviation of dissolved inorganic carbon) of lake waters with changes in atmospheric 14C levels ( Xatm). The XDIC/Xatm ratio of Lake Qinghai was found to be about 0.790. The reconstruction of HWE was established based on the XDIC/Xatm ratio and the well known changes of Xatm. The age model ( based on 5 14C dates) of QH-2000 sedimentary core was corrected by the temporal changes of HWE. It showed that the shifts toward old ages for 14 C dates of Lake Qinghai's sediment was mainly due to HWE and the reconstructed HWE was 1100a in the early Holocene, which slowly rose to 2150a in the latest Holocene ( pre-bomb era) and then shifted to 1313a in 2005 AD. It was also val idated by the measured HWE, which was determined to be ca. 1000a, 2300a and 1500a correspondingly. A "HWE correction table" was established for Lake Qinghai so as to transfer any given calendar age without HWE correction into a corrected calendar age. The published redness curve based on our corrected age model shows rapid climate changes (RCC) correlative to those indicated by many records all over the world. The RCCs include those occurred during 9000-8000 cal aBP, 6000-5000 cal aBP, 4200-3800 cal aBP, 3500-2500 cal aBP, 1200 -1000 cal aBP and 600 - 150 cal aBP.