基于KronosFlow软件对逆冲推覆带构造-热演化的初探

盆地模拟是含油气盆地勘探评价的重要技术方法之一，然而传统的盆地建模2D模拟技术仅适用于拉张型盆地，使得挤压型盆地横向上的热史重建一直是个难题，从而制约了进一步的油气勘探。目前由法国Beicip-Franlab公司设计的KronosFlow软件突破了传统盆模软件对逆冲推覆带、盐构造和泥底辟等复杂构造的局限性，精确控制了横向和垂向上的构造位移，通过跟踪单个网格连续运动形态、恢复侧向变形量以及与TemisFlow软件无缝衔接，实现了对挤压型盆地埋藏史、热史、生排烃史以及油气运聚史的恢复。以塔里木盆地北缘柯坪逆冲推覆带和库车逆冲推覆带为例，利用KronosFlow软件定量反演了新生代以来的构造-热演化历史，并以实测数据约束并验证挤压环境下盆地模拟结果的有效性。柯坪逆冲推覆带的依木干他乌断层在40~30 Ma再次活动，断层附近志留系—泥盆系的温度大于85 ℃，柯坪塔格断层在15~10 Ma活动，断层附近志留系—泥盆系的温度小于70 ℃，寒武系（烃源岩成熟度为1.3%~1.7%）和奥陶系（烃源岩成熟度为0.7%~1.2%）烃源岩热演化程度高，生烃能力强。库车逆冲推覆带侏罗系北段温度介于50~70 ℃，南段温度介于210~230 ℃，盐构造造成地温异常，其中秋里塔格构造带膏盐岩最厚，降温效果最明显。

A KronosFlow software-based preliminary study on the tectono-thermal evolution of thrust-nappe belt

Basin modeling is an essential technical method for the exploration and assessment of petroleum basins. However, traditional 2D basin modeling technologies only apply to extensional basins. This makes the thermal history reconstruction in lateral direction of compressional basins an unsolved problem and thus restricts oil and gas exploration. The latest KronosFlow software developed by the French Beicip-Franlab company breaks through the above limitations of traditional softwares on complex structures such as thrust-nappe belts, salt structures, mud diapir structures, and precisely controls the lateral and vertical structural displacements. We restored the burial history, thermal history, hydrocarbon generation, expulsion history, and hydrocarbon migration and accumulation history of compressional basins, by tracking the continuous motion pattern of a single grid, restoring lateral deformation and seamlessly interacting with the TemisFlow software. We then used the KronosFlow software on the Kalpin and Kuqa thrust-nappe belts in the northern margin of the Tarim Basin for quantitatively inverting the tectonic-thermal evolution history of the thrust-nappe belts since the Cenozoic. The modeling results were consistent with the measured paleo-thermal indicator data, confirming the validity of the results of this software for the compressional basin. The Yimugantawu fault in the Kalpin thrust-nappe belt was reactivated during 40~30 Ma, and the temperature of the Silurian-Devonian near the fault was higher than 85℃. The Kepingtag fault was active during 15~10 Ma, and the formation temperature was lower than 70℃. The Cambrian (maturity of source rocks between 1.3%~1.7%) and Ordovician (maturity of source rocks between 0.7%~1.2%) source rocks have a high degree of thermal evolution and strong hydrocarbon generation ability. The temperature of the Jurassic strata in the Kuqa thrust-nappe belt ranges from 50 to 70℃ in the northern section and 210 to 230℃ in the southern section. The salt structure results in geothermal anomaly, among which the salt rock in the Qiulitage structural belt is the thickest and the cooling effect is the most obvious.